Where other buyers exist, producers may try to increase property rights and bargaining power by retaining ownership of any surplus yield. For example, the contract could explicitly reserve any production surplus over the maximum to the producer or preserve the right of the end-user to request surplus biomass priced under the contract’s default compensation provision. On the other hand, contracts also must consider allocation of catastrophic risk. Over time, it is likely that weather, pests, drought, flooding, wind, or hail will impact biomass production on a given farm. No such product exists for biomass as of this writing. End-users require a consistent supply to accommodate conversion facilities, but a biomass farmer that fails to harvest a crop 243 has no revenue to perform the contract via spot market purchases—especially when there is no spot market for biomass. Accordingly, contracts should specify conditions for performance excuse and contingency provisions. Moreover, in the absence of a government safety net along the lines of crop insurance, biomass contracts should consider minimum revenue provisions to provide the farmer with some compensation. One way to soften this effect on the end-user is through the use of an amortized payment schedule. Producers would receive a guaranteed cash flow during all years of production to cover costs, but later payments could be diminished to allow the end-user to recover the costs throughout the life of the contract. Contracts could also require crop insurance, once available, botanicare trays and use insurance proceeds to offset initial contingency provisions.Once the crop is established, producers face a number of issues during the growing phase.

Some production contracts may require very specific production practices in order to decrease end-user supply risk and require monitoring of crop quality. These requirements decrease producer autonomy, and diminish potential gains from producers’ individual management skills and experience. Heavy requirements may also restrict the producers’ flexibility to adjust management practices to various production environment scenarios. On the other hand, considerable production risk arises from inexperience and lack of knowledge with producing energy crops. Inexperience or ignorance may cause a producer to adopt a production practice harmful to the crop or environment. In addition, the producer may be unsure how to address new production hazards, such as a new pest, drought conditions, or invasiveness. Thus, inexperience and lack of knowledge creates risks and costs for producers. End-users may desire to increase producer control through the biomass production agreements. As a general rule, however, contracts should allow producers as much freedom as possible to choose production practices. A principle of the Sociological Compatibility perspective is that producers value autonomy and demand compensation in some form for the loss of autonomy to satisfy participation constraints. Moreover, adjusting cultural practices is a traditional risk management tool for producers. For example, producers may choose to apply fertilizer in the fall to avoid higher prices in the spring, decide to plant later to avoid risk of a late frost and insect pests, and producers may choose to plant herbicide resistant crops and apply herbicides rather than mechanically cultivate crops to reduce weed competition. Because incentive contracts enhance producer risk, and rigid production practices foreclose other risk management strategies, other methods of dealing with end-user production risk are preferable. In other words, production practices have very poor separability, and thus respond poorly to incentives.

A better strategy may be for biomass production agreements to employ the use of generalized legal standards rather than specific practices to control production, which would shift contracting costs from the front to back end, while providing greater producer autonomy. A singular focus on incentives to maximize yield, however, is fraught with potential downside risks to long-term sustainability and suitability with end-user needs. For example, there is a tradeoff between corn stover removal, soil erosion, and fertilizer inputs. Removing high percentages of crop residues increases the risk of soil erosion from water and wind. Excess stover removal to increase per acre yield in one year will require additional fertilizer for the following crop year. Excess fertilizer can then impact the composition of the resulting biomass, especially its mineral content, which can then impact the ethanol conversion process. Additional fertilizer application also shifts the carbon footprint of the biomass feedstock or precipitates other environmental externalizes . Research also has suggested that the loss of soil organic carbon serves as an additional constraint for corn stover harvest. Similarly, harvest timing and cutting depth of both corn stover and perennial biomass crops must balance yield, moisture content, nutrient storage in the rootstock, soil compaction, and wildlife habitat over the winter. At the establishment stage, producer discretion in initial crop variety selection could impact potential invasiveness or migration of genetically engineered plants.  Accordingly, incentives in biomass supply contracts should provide producers sufficient flexibility to manage production and harvest decisions within the context of their other farming operations and long-term environmental values. As discussed in more detail in Section IV, infra, sustainability standards address many of the environmental tradeoffs identified above and embed balancing criteria to allow for producer autonomy within the context of environmental, social, and economic sustainability. Incentive contracts could look to or even incorporate third-party sustainability certification programs for guidance in allocating risks and responsibilities among producer and end-users with respect to balancing yield with environmental impacts.

In addition to, or complementary with, third-party sustainability certification, monitoring through the use of fieldmen may provide the most favorable strategy to address moral hazard during establishment and maintenance. Although developing the fieldmen model may take time, the benefits discussed in the framework likely outweigh the costs. Contracts can incorporate this model by elaborating on the “cooperation provision” outlined in the information sharing section. In addition to requiring notification of any material change in circumstances that may affect performance of either party’s obligations, the contract could create a right of the end-user to inspect the producer’s premises. In order to be of value to producers, end-users should employ the services of agronomists or individuals with knowledge and experience in biomass crop production, a requirement likely worth adding into the contract. Qualified fieldmen also can provide an excellent avenue for information sharing and education—an important risk management tool. In addition to inspections, the contract should authorize producers to request fieldmen services. Moreover, fieldmen could be enabled to authorize contract modifications or excuse performance. This strategy enhances producers’ social interaction factors, and could be coupled with assistance for sustainability standard certification.End-users deploy biomass production agreements to secure a stable supply of biomass, as well as other important characteristics, such as moisture level, foreign matter, mineral profile, BTU content, size and shape, and its environmental footprint. Risk arises when the producer is required or incentivized through penalties or bonuses for these crop attributes. While the producer may have control over some attributes, others evade manipulation. Strict consequences, such as rejection or price docking, create large risks for producers. Moreover, when minimum requirements are defined loosely, end-users may be able to engage in opportunistic behavior. To minimize holdup, biomass contracts should incorporate reasonable margins of error to account for normal environmental characteristics, as well as procedures for third-party verification and re-measurement.Storage and transportation of the low-density, high-volume biomass from the producer to the end-user presents unique challenges and should be considered carefully in the biomass supply contract. Assigning responsibility for storing and transporting implicates both risk- and cost-minimization strategies of contract design. For example, a set delivery date in the contract provides certainty, but indirectly assigns the storage burden—perhaps to both parties—and requires careful planning. On the other hand, an “on end-user demand” clearly shifts responsibility for storage to the producer and may dictate harvest timing despite other agronomic or environmental considerations. In contrast, an on-harvest delivery term places storage responsibility—and attendant risk of loss—on the enduser. Transportation responsibilities tie directly into product specifications and storage. If the contract requires certain harvesting methods or preprocessing requirements, flood table such as pelletizing or densification, the farmer may incur significant upfront equipment costs to produce the required result. However, some producers seek flexibility to minimize processing and transportation costs, such as forage chopping, directly into road transportable wagons, or pelletizing biomass in the field to decrease volume. In sum, up-front consideration should be given in the contract to linking product specifications with optimal storage methods to minimize post-harvest loss and maximize transportation efficiencies. The very high level of asset specificity, along with specialized equipment, places significant post-harvest risk in the farmer who has little bargaining power in a single-buyer market.

Accordingly, a more complete contract to minimize hold-up risk may be necessary to induce contract acceptance by the farming community.From a producer perspective, several factors influence the choice of land for biomass production. Perhaps most important is opportunity cost. In the Midwest, where much of the land is highly productive and can support currently higher value crops , energy crops, such as Miscanthus and switch grass, are unlikely to compete for scarce land resources. Biomass may be relegated to more marginal lands with lower opportunity cost, such as pasture or hay ground. Perennial biomass crops do provide, however, a number of environmental benefits, such as erosion control, improved soil and water quality, increased wildlife habitat, and increased soil organic carbon. Producers, therefore, may want to take advantage of these benefits and grow energy crops on at least marginal land to provide these long-term and environmental benefits. In addition, studies have shown that soil types can affect the composition of biomass plants, such as the percentage of lignin, cellulose, ash, and mineral content. In this way, land choice can significantly influence the quality and value of the resulting biomass crops. End-users have two strong preferences concerning the choice of land. First, in order to secure a stable biomass supply, endusers would prefer to tie biomass production to land title, rather than tying production requirements to individual producers. This strategy permits end-users to be less concerned with producer default, as land resources remain dedicated for biomass production. Other than outright purchase of land by the enduser, more creative avenues exist, such as equitable servitudes, covenants, or easements, to produce biomass that would attach to land title and provide more supply security than long-term lease agreements. Second, end-users prefer that biomass production be located near the end-user’s facility to decrease transportation costs. Where the end-user assumes the responsibility of transporting the biomass, local production is especially important. Longer transportation routes also increase greenhouse gas emissions, thereby decreasing the energy balance of the crop. Local production creates cost and risk for producers in two main ways, however. First, producers lose the traditional agriculture risk management strategy of geographical diversification; they cannot spread out production over larger areas to decrease weather and pest risk. Second, requiring local production limits the producer’s ability to produce energy crops on marginal ground or land exiting the Conservation Reserve Program. These production dynamics create a number of concerns for producers. First, as discussed in the Sociological-Compatibility Perspective, a producer may be unwilling to relinquish that level of control over his land; producers’ land is usually their most critical asset. Second, the greater the degree the land title is locked into biomass production, the greater the level of asset specificity, increasing the risk of holdup or renegotiation. Moreover, most producers grow crops on a combination of owned and leased land, with farmers depending on rental land resources to achieve economies of scale. Tying biomass production to land title, therefore, tightens the producers’ participation and incentive compatibility constraints and necessitates higher compensation.On the other hand, the multi-year production cycle for perennial biomass crops injects unique risk concerns into the farmland rental market. Producers may have difficulty securing leases for the duration of the production contract or even the life cycle of crops, such as switch grass and Miscanthus. Moreover, landowners may be concerned with the short- and long-term effects of biomass production on the land itself, or how to remediate the land back to its prior use if the end-user defaults on the biomass supply contract—a particular concern due to asset specificity. To provide safeguards and regulate producer practices, traditional leases have often relied on legal standards and duties . 

Offered the choice of these two contracts, the high-cost producer will choose Contract 1, as he will profit $1, and cannot profit from Contract 2, as his costs outweigh the compensation for 100 tons. The lowcost producer will always choose Contract 2. Although he could profit $2,301 under Contract 1, Contract 2 is designed to allow the low-cost producer to profit $2,302 and produce the maximum of 100 tons. This menu of contracts thus satisfies both producers’ participation and compatibility constraints, and incentivizes both parties to reveal their types by their contract choice. Note that offering this menu of contracts results in higher production at lower costs than rationing . Note also that the end-user still must pay the low-cost producers’ information rents in order to incentivize acceptance of the contract designed for the low-cost producer. Screening thus decreases, but does not eliminate, the rents low-cost producers can extract from private information. The amount of biomass that the high-cost producers can contract is also limited in order to make the high cost contract less desirable for the low-cost producer. Additionally, screening may limit producer participation. Screening presents another significant challenge for Principals. In order to design a menu of contracts to satisfy both the participation constraints and incentive compatibility constraints of producers, the Principal must have detailed knowledge of the characteristics and distribution of each type of producer. To the extent that an end-user’s understanding of producers is lacking, especially in a fledgling industry such as energy biomass, trimming cannabis the value and feasibility of screening may be limited severely. A third method to address adverse selection is through the use of auctions, specifically procurement auctions. In a procurement auction the buyer invites bids from suppliers for a specific contract. 

In auctioning, the lower-cost producers can still extract information rents from the end-user, as they must only offer a price just below the next lowest bidder, a strategy called bid shading. Therefore, they always offer a bid higher than their minimum bid, extracting the difference as information rent. The lower-cost the producer, the higher the information rent they can extract, while the highest-cost producer again cannot extract any information rent. While auctions again only minimize and do not eliminate information rents, auctions provide several advantages over other methods, such as screening or rationing. In theory, auctions can reduce the information rents without limiting production . For example, while rationing uses fixed prices and screening limits to decrease the attractiveness to low-cost producers, auctioning uses competitive bidding to achieve the same purpose. Finally, auctions dispense with the need of the end-user to know the cost distribution of different types of producers, and reveal changes in this cost distribution over time. On the other hand, auctions present some unique challenges. They require a critical mass of bidders to ensure competitive bidding, and create more uncertainty for the buyer , as they offer fewer predictions of producer responses. In addition, auctions can be costly and complicated to design and administer. A final strategy to address adverse selection is signaling, where the informed party acts first to reveal their private information to gain an advantage. This strategy has direct implications for both Principals and Agents. In a simple form of signaling, the Principal gathers information on observable characteristics of producers that are correlated with opportunity cost or other hidden information variables. Based on this information, the Principal can create minimum eligibility requirements for contracting. However, to prevent low-cost producers from masquerading as high-cost producers, the observable characteristics must be costly to fake. Also, information collection can be costly, and “the ability of this information to reduce information rents without distorting [production supply] will only be as good as the strength of the correlation between the characteristics and [producer types.]” 

Some producers, may also find it in their best interest to take the initiative to use signals to reveal their private information . End-users can increase supply while limiting the potential for information rents by contracting with high-cost producers that effectively signal their type. By requiring signals that are impossible or costly to mask , the end-user can obtain the added production from high-cost producers without the risk of paying increased information rents from low-cost producers masquerading as high-cost producers.While adverse selection problems arise during contract negotiation, moral hazard emerges after the contract is signed. Moral hazard exists where the Agent makes a decision that affects the utility of both the Agent and the Principal, the Principal can only observe the outcome of the decision, which is an imperfect indication of the action, and the action that the Agent would take to maximize his utility does not simultaneously maximize the utility of the Principal . Information asymmetry in this case again gives rise to opportunistic behavior on behalf of the informed party, as they may shirk their effort. Literature from sociology and economic contract theory has developed several tools to address moral hazard problems. To model this problem, we offer a second simple example in which an end-user has contracted with a producer to produce and deliver biomass. Assume that a producer’s yield depends on two variables: his effort , which is costly to the farmer; and the weather. The end-user and producer have signed an acreage-based supply contract, where the farmer is to deliver the entire crop from 50 acres of land to the end-user for a fixed price per acre. This scenario gives rise to moral hazard, as the farmer has an incentive to slough off, a decision that conflicts with the interest of the end-user seeking to maximize yield from the land under production. Perhaps the most powerful tool available to address moral hazard is incentive contracting, developed in complete contracts literature. However, incentive contracting also creates the trade-off between risk and cost discussed earlier in the Risk Minimizing Perspective. 

The economic contract literature assumes that only the outcome of the Agent’s decision is observable, and thus the Principal can only influence the choice the Agent makes by conditioning the Agent’s utility on the outcome. However, because the outcome is imperfectly correlated to the Agent’s actions due to the variability of weather, basing the Agent’s utility on outcome imposes risk for the Agent. Once again using mechanism design, the Principal must maximize his utility subject to the producer participation constraints and incentive compatibility constraints. The incentive compatibility constraints imply that the contract must provide enough incentive that the producer prefers to put forth effort. For example, the producer must profit more from applying fertilizer than from failing to apply it. In our example above, where the end-user can only observe yield, the end-user can only base incentives on yield. Because application of fertilizer positively correlates with yield , the end-user could modify the contract to award a bonus for achieving a certain threshold of yield. If the end-user can renegotiate the current contract, he might desire a price-per-ton contract over an acreage contract, to tie the Agent’s utility to outcome . The proposition is quite a simple one: the end user will give the Agent a higher payment when the end-user can infer from the outcome that the Agent made a favorable decision, and vice versa. While both these solutions may satisfy incentive compatibility constraints by incentivizing the farmer to put forth effort, they also increase risk, which serves to tighten a producer’s participation constraints. In order to incentivize the producer to accept the incentive contract, the end-user must also satisfy the producer’s participation constraints. Participation constraints may include a host of factors, economic and non-economic, and the producer’s aversion to risk. Therefore, cannabis drying rack as risk is passed to the producer to satisfy incentive compatibility constraints, end-users must provide larger payments to satisfy the producer’s participation constraints. The extra compensation that the Principal must pay is an information rent that arises from the asymmetric information between the parties. Within this general theory, several important principles emerge. First, the smaller the expected difference between outcome of a favorable Agent action and an unfavorable one, the larger the incentive must be to motivate the Agent to act. The reason is because it becomes more difficult to distinguish between the Agent’s action and inaction. Also, the optimal strength of incentives is dependent on several factors. Second, the greater the value of any additional producer effort and the greater effect the incentive will have on the producer’s behavior, the stronger the incentive should be. Finally, the tradeoff between risk and incentive implies that weaker incentives should be given to more risk-averse producers. A more difficult problem arises, however, when a Principal has multiple objectives to maximize, and a producer’s single action affects both objectives. When a producer’s action supports one goal and opposes the other, incentive conflicts arise. The optimal balance will occur where the marginal benefit gained from incentivizing the producer to act to support one objective is equal to the marginal cost of the detriment to the conflicting objective. The value of incentive contracting is limited by more than the risk-cost tradeoff. Incentive contracts assume that outcome, and only outcome, is observable, and the Principal cannot gather additional information. Incentive contracts also assume that the Principal has no way to force the Agent to act.

While in some scenarios these two assumptions hold true, the agricultural context provides unique opportunities to employ additional tools to manage incentives.Incentive contracts rely on “quality measurement,” an observation limited by numerous factors, including the above mentioned inability to distinguish between quality arising from producer effort and quality arising from fortuitous circumstances . While yield is fairly easy to measure, other crop/production characteristics are more difficult to assess at delivery, such as moisture and ash content; carbon footprint; and other sustainability attributes . Large crop volumes, high costs of measurement technology, limited time, and logistical complexities further limit measurement ability. Also, when measurements are controlled by a single party, the risk of opportunistic behavior arises from measurement errors or fraud. Parties can address this risk, although at a cost, by employing third-party verification or allowing the other party to re-test. These terms refer to measurement characteristics of a transaction that reflect both the asymmetry of information and the costs of monitoring or verifying individual performance. Separability refers to the “ability to evaluate an Agent’s effort just by observing output,” or “how much of the quality/quantity of the product is measurably attributable to the producer’s management efforts[.]” Programmability refers to “how closely output is tied to specific input decisions and observable management practices.” Production processes that are highly separable are appropriately addressed by incentive contracts, as the “allocation of value and risk will be efficient.” Utilizing incentive contracts for production processes that are not separable creates weak incentives, increases producer risk, and also creates risk of opportunistic behavior by the producer. If production is not separable but highly programmable, contracts can better address moral hazard by controlling the production process, depending on the cost of monitoring. Increasing control through more complete contracting has several drawbacks, however. First, end-users must incur the cost of writing and enforcing additional contract provisions, which may require additional monitoring and enforcement effort. Decreased producer autonomy also requires compensation to overcome participation constraints and disallows potential gains from the producer’s specialized knowledge and skills. Two common examples of this type of control in the agricultural context are production contracts for poultry and hogs—both of which have engendered substantial farmer criticism due to perceptions of feeling trapped or intimidated by the contracts offered by the end-users of their products. An alternative method for the Principal to manage moral hazard is via monitoring. One policing model that end-users could employ is the use of field men, who periodically visit producers. Creating a network of field men yields a number of benefits. First, monitoring in this way increases the number of observable variables, by not only observing directly the production capabilities and practices of individual farmers, but also observing the production environment beyond the producer’s control, such as weather and pest problems. If the field man perceives opportunistic or suboptimal behavior on behalf of the producer, the field man can address the problem before damage occurs to the crop. Although field men may be perceived as “supervisors, spies, or adversaries,” they can provide multiple benefits for producers, and farmers rarely have negative perceptions of these observers.

UK farmers indicated to me that such practices might give them an edge in meeting food safety concerns, but would be simply impossible due to how they would change the farm’s outward face. Part and parcel of this issue, UK “right to roam” laws grant the public the right to walk freely across privately owned parcels of land, along with their domestic animals. This comparatively open and unsecured way of managing farms would make many of the secure fencing and private property-based exclusion measures common in CA incongruous with the English rural landscape, and, in some cases, potentially illegal or flat out impossible to implement. When I surveyed on-farm practices for food safety and conservation, UK farmers were especially unlikely to remove vegetation from around ditches, ponds, and field margins. When I asked them why, farmers indicated to me that the idea of doing so seemed to conflict not only with the right to roam, but also with a popularly held idea of the proper role of a farm as a wild environment. During our interviews UK farmers often noted that local community-level rules governing the cosmetic appearance of agricultural fields and associated facilities would prohibit the removal of vegetation around field margins, ponds and watercourses which otherwise serve a scenic purpose. Even without that constraint, treating the farm as something other than a wild place did not seem right to the majority of farmers I spoke with. Those who did not espouse this view operated the largest farms in my sample, and were those most likely to protect their crops under the cover of large scale glasshouses. California’s longstanding legacy as a highly capitalized agricultural economy dominated since its founding by large farms, commodity crops, drying weed and production-oriented agricultural methods has created a long-standing capitalist framing and sense of separation between agricultural and residential or recreational lands .

Farming in California is clustered into areas of historical agricultural intensification, far from the population centers of urban and suburban living. On these dedicated agricultural expanses, land management decisions are somewhat insulated from conflicting suburban views of what agriculture should be or should look like. The sheer amount of land available for agricultural use in the United States generally and California specifically has allowed agriculture to make its own rules, less concerned with sharing space with nearby towns. California farmers I interviewed indicated that they were consumed entirely by the challenge of maintaining the land they have while producing the crop their buyers wanted to see, in the ways required by law, standards, and buyer requests. They primarily focused on economics and capacity when deciding how to do so, and what it looked like to anyone outside of the farming lifestyle was essentially immaterial. Illustrating this difference, the California farmers I interviewed agreed with their UK counterparts that agricultural lands can serve a valuable purpose as wildlife habitat if practices such as clearing buffer strips and erecting wildlife exclusion fences are not undertaken, but this fact was most often mentioned by them as a serious liability rather than a competing desired outcome. At best, it was noted as a fraught conflict between different sets of values; on the one hand, there were what they saw as the ideals of environmental health, or romanticized notions of productive wilderness and movements ‘back to the land’, and on the other side came the discordant reality of what is feasible on tight economic margins and large commercial contracts, and what is simply too risky to—quite literally—bet the farm on. Their explanations highlighted values echoed by my UK sample: commitment to safe food, respect for nature, and the desire to protect both the long-term financial and ecological viability of their farms. However, California farmers in my sample did not mention being motivated at all by values associated with the scenic appearance of their fields, or the accessibility of their land for recreational value.

These values did not appear to be strong motivators for their practices in comparison with the clearly articulated expectations of food safety audits and buyer requirements.Lastly, as my field work progressed, I found growing evidence that farm ownership patterns may be having a specific impact on certain kinds of food safety efforts. Specifically, farmers with a deep personal connection to the land they farmed described their on-farm food safety practices in language that made explicit reference to environmental health as a component of safe food. Since the late 19 century with the advent of modern farming technologies and increasing th concentration of populations in urban centers, many the industrialized nations of the Global North have experienced a sharp decline in the percentage of their populations working in agriculture . Falling numbers for population working in agriculture come on the heels of rising farm productivity and the development and proliferation of non-agricultural employment opportunities, all of which combine to endanger family farm ownership and the transgenerational transfer of farming knowledge. However, UK regulators and trade associations stressed for me that the majority of the farmland in the UK is nevertheless still family-owned and operated, often by families that have run their farms for generations. “It’s a long game,” I was told by one trade association representative who worked closely with farms. “This land has been theirs for a long time.” My archival research echoed this finding, and my interviews bore this out as well. Most of my UK farms still under direct family ownership. In 7 several cases, I interviewed the farm’s owner, who was also the on-site harvest manager, and who shared a surname with the commercial name of the farm. Several more of my UK interviewees represented associations of several small family farms that had banded together to achieve economies of scale in a competitive agricultural market, but in a way that preserved individual family management of original family-held lands. Once this history was spelled out, I could see that the names of these companies often reflected their conglomerate nature through acronyms or group nouns composed of the sum of their parts. Importantly though, each family remained in control of the land it had brought to the association. Management decisions were still made at the local level, by the manager of each individual farm.

Several times my questions about farm management could only be answered by my initial interviewee for their section of the farm’s land, and I had to be routed to another family within the association to hear about management on their portion of the farmland . My work in CA suggested a subtle difference here, which was outside the scope of my research and would need to be verified and explored further. Family farm ownership is certainly not unknown in CA, nor is it especially uncommon. Several of my CA interviewees represented family-owned farms, even if the farm had never carried the surname of the individuals running it. Even one of the CA farms I spoke at length with, that was among the largest and the most factory-run and thus potentially the farthest from a pastoral family farming ideal, had started at one point as family farm and grown through land acquisitions. What I found important here was that the land had been acquired, not simply joined together in name. What had been a large number of independent holdings, some of which may have originally been family operated, was now a large conglomerate run by managers who do not and have never had a personal family association with the land they now manage. One of the farm managers I spoke with who worked for a CA grower that splits its production between California and Arizona depending on time of year, vertical growing systems told me that he moves to Arizona when the season there begins. Neither place is home, he reported; his family is in Georgia. This is a job.8 Scholars examining the sociology of rural agriculture have noted instances of this difference in other places and at other times. Comparing environmental regulation in the UK and US in the mid 1980s, David Vogel notes that greater population density and less available arable land in the UK has been a factor in making conservation and land use issues take center stage more easily than in the US . In the US, Julie Guthman has explored the history of California farming and its lack of a true family-farm agrarian past at any point. Instead, farming in CA has been pushed toward larger-scale and more production-oriented models that focus on large farms and high valuable crops, in part because of the high property values of CA land . From the descriptions offered by my interviewees, it appeared that persistent differences in how farmland is held and operated in CA and in the UK could be partly responsible for influencing farmers’ decisions about the importance of maintaining environmental sustainability practices alongside food safety requirements. If some degree of continued family ownership and personal connection to both the past and future of the land increases family farmers’ ability to think about food safety requirements with a long-term sustainability framing, this difference in land ownership patterns could be creating an environment where US farms’ environmental future is more likely to be discounted in favor of present food safety and economic concerns. However, UK farmers have already experienced and responded in their own ways to market pressures that have incentivized larger landholdings and more intensive production, finding ways to adapt that still preserve family ownership. As the UK grapples with the coming challenge of competing on a global marketplace as a single nation apart from EU common market, it is unlikely that these pressures will lessen. Thus, UK agriculture may be in a transitional period, and headed for a new period of changes in historical patterns of family farm ownership.In the years since my research first began, the state and non-state food safety controls examined in my study have undergone several important changes with the goal of reducing the duplicative and redundant landscape of safety controls active in the fresh produce market. One of the first such efforts was the Global Food Safety Initiative bench marking effort. Since its launch in May of 2000, GFSI bench marking has attempted to certify for equivalence many disparate food safety standards operating in multiple food supply chains around the world. GFSI gained recognition in 2007 after seven major global retailers announced they would accept any GFSI-bench marked safety standard. Nevertheless, wider acceptance difficulties remained, and 9 events such as the 2006 outbreak of E. coli in California spinach caused a further proliferation of standards rather than an easy convergence around fewer standards or robust bench marking. After a lengthy and remarkably inclusive multi-stakeholder process with the goal of identifying a single safety standard that could serve as a commonly accepted guaranteed of good practices in any national or international market, the United Fresh Harmonized GAP Standardwas created in 2016. In partnership with GlobalG.A.P., the Harmonized Produce Safety Standard was born , and later became the USDA Harmonized GAP standard. However, the multi-stakeholder harmonized safety standard created in the aforementioned process was not unified for long; in the course of obtaining GFSI bench marking, GlobalG.A.P. was forced to update its harmonized standard to a version different from that adopted by the rest of its partners in the original harmonization process, creating a proprietary GlobalG.A.P. 10 harmonized standard alongside the USDA Harmonized GAP standard. The differences between those two standards were small, but in essence, there were still multiple standards even after the harmonization efforts and the attempts to use bench marking to level playing fields between different standards. In the context of my research, the private standard for which I gathered the most evidence of positive outcomes in farmer experience and environmental sustainability, the Tesco NURTURE program, has also now been subsumed under the umbrella of the most recent Global G.A.P. HPSS. The Tesco NURTURE program provided much of the basis for my conclusions favoring the results from private standards that use a balance of regulatory styles and a wide view of food safety that includes environmental considerations. Both Global G.A.P. and NURTURE were among my category 4, representing standards that were the most balanced in both style and focus. As a module within the newest version of the Global G.A.P. standard, NURTURE’s transformation is an early example of one possible outcome of ongoing efforts to achieve harmonization between the many overlapping food safety standards current active in fresh produce markets.

Additionally, two of the standalone standards were excluded from the analysis: Marks & Spencer’s ‘Field to Fork’ was excluded entirely because an audit checklist could not be obtained for review, and GlobalG.A.P. was excluded from analyses of farmer opinions and practices because only four farmers in my survey results for either nation claimed to carry this certification. The results presented here represent a combination of personal interviews and archival research, conducted during field research between 2014 and 2017 in multiple locations across California, and the United Kingdom. I report here the results of two different survey efforts. The first survey, piloted and released in 2014 to members of the California Farm Bureau Federation, yielded data for forty-nine California lettuce growers as part of a larger survey effort covering 965 California growers of a range of crops . This survey was designed to update prior 3 scholarship examining food safety measures among California farms since 2007. For the purposes of my research, I conducted five additional in-depth interviews with California farmers, two with regulators, and three with academic researchers to contextualize the results of that broader survey and inform my analyses of the responses of lettuce farmers who took part. The second survey reported here includes data from twenty-one in-depth interviews I conducted with UK farmers of leafy greens, designed to mirror the structure and topics of the survey delivered to California farmers. Further information is provided by nine additional in-depth interviews with representatives of major UK grocery retailers, academic researchers, indoor grow methods farmers’ trade associations, and food safety regulatory personnel, conducted in the United Kingdom between Summer 2014 and Spring 2016.

In-depth interviews during both research efforts followed a semi-structured format tailored to each interviewee’s unique position of knowledge within the food system, focused on elucidating the mechanisms behind how decisions are made at both the regulator and food retail industry level, what food safety and environmental pressures farmers experience, and in what ways differential value is placed upon food safety goals and environmental outcomes. Both farmer surveys contained approximately 30 questions, ranging from farm area and crops grown, to perceptions of the food safety regulatory framework, to field level management practices in place for food safety or for the promotion of environmental protection. Full interview questionnaires for my California and UK survey efforts can be found in Appendices I and II, respectively. To understand the social impact of overlapping state and non-state food safety controls, respondents were asked to specify what, if any, food safety certifications they currently held, and how they felt about the certification process and the public regulatory landscape around food safety. Farmers were additionally asked to assess which actors in the lettuce supply chain held the most power in setting field-level farmer practices, and in shaping the overall food safety regulatory landscape. Field level production practices were analyzed quantitatively, by assigning each farmer scores for food safety and environmental conservation. Interviews conducted in person followed the general structure and questions of the survey questionnaires, while also incorporating additional questions and further exploration of survey topics led organically by interviewees’ interests and expertise. To supplement data from interviews and survey results, I also present insights from an analysis of regulatory styles found in state and non-state food safety controls. To compare methods of state regulation of food safety across the United States and United Kingdom, I evaluate the most relevant food safety laws in each nation for their regulatory style and topics of primary focus.

To illuminate the landscape of non-state food safety standards, I present a comparative analysis of the structure and written requirements of eleven produce safety standards operating across the UK and California. Each standard was evaluated through its certification audit checklists, by assessing each audit clause or certification criterion within the standard for its topic focus and its regulatory style , enabling a quantitative comparison between standards. To compare the regulatory landscape emerging from the overlap of these state and non-state controls, I compare the approaches of both private and public food safety controls by organizing them into four categories based on focus and style. Because the two farmer surveys summarized in this dissertation were conducted during separate field seasons and survey efforts, the total number of respondents for each survey is not equivalent. Twenty-one UK leafy greens farmers were surveyed, compared to 49 US farmers. These differences reflect differences in response rate, as well as limitations due to amount of time in each location and different recruitment methods. In addition, because participation in data collection was entirely voluntary on the part of farmers, not all survey respondents chose to answer all questions on the survey, with the end result that the number of responses analyzed from each respondent group varies slightly from question to question on both surveys. Survey questions themselves also differed in some respects between my US and UK surveys. The survey instrument used for UK farms used slightly different language from that used in California, an intentional step designed to adjust for local differences in terminology related to various practices, as well as different local concerns, local policy bodies, and local supply chain structures. As a result, some information is reported for only one study population, and any comparisons of non-parallel data types will be clearly noted. Additionally, all reasonable efforts were made to ask questions in locally appropriate language and terminology for each study population, resulting in slight variations in wording between the two surveys.

Rather than increasing differences between the surveys, these adjustments were intended to reduce variation resulting from differences in language, and to ensure that variation observed was a faithful representation of actual practice and actual perceptions of governance institutions.This study focused on evaluating public and private standards and their impacts on farmer practice and farmer decision-making as a result of produce standards and regulations. Because my focus was on farmer experience, and farmer decisions in the realm of environmental conservation—the ultimate outcome of multiple overlapping governance forces as seen by farmers rather than by regulators—I did not specifically investigate details of how the preregulatory risk assessment scheme Red Tractor Assured Produce and the industry-led harmonization effort by the British Retail Consortium may influence the form that public regulation takes in the UK, or the articulation of public and private regulatory processes. Rather, I have evaluated those two standards at face value as component standards within the regulatory landscape, because that is how farmers experience them. For similar reasons, I have compared the explicitly pro-environmental Linking Environment And Farming standard alongside other non-state food safety controls with fewer explicit references to environmental conservation because farmers indicated that they regard LEAF as a safety standard comparable to any other I examined. My analysis acknowledges and aims to engage these differences as a meaningful indication of how environmental conservation is valued by a range of food safety controls active simultaneously in the lettuce production market.As a starting point for my comparison, I examined the state regulatory frameworks in place for produce food safety in the United Kingdom and United States. At the time of this research, the UK was a member of the European Union, meaning that national food safety regulation in the UK is shaped by EU requirements, and vice versa, in a shared governance arrangement that incorporates a multi-level strategic bargaining process and two-way transfer of priorities . The top levels of EU food safety regulation take two different forms: regulations and directives. Regulations apply to member states directly, cannabis dryer without any need for member states to create local interpretations. Directives, conversely, are general guidelines which member states must adapt to local contexts and implementation systems. Food safety goals are articulated here as broad principles which are meant to guide member states’ actions as they construct action plans specific to their industries and local administrative authority structures. Action plans must fit within the broad principles set forth by European Food Safety Authority , but must put them into practice by providing enforceable local regulatory specifics. Beginning at the highest levels of state regulation applicable for leafy greens production in the United Kingdom at the time of this research, European food safety rules are presented in Reg EC No 178/2002. This regulation standardizes food safety goals and definitions for EU member states and forms the backbone of the European food safety system. The regulation does not specifically address food safety concerns in individual foodstuffs or their respective supply chains, but rather focuses on establishing basic terminology and expectations, along with the procedure to be followed in cases where problems are known or suspected.

The regulation’s stated goals of “a high level of protection of human life and health and the protection of consumers’ interests, including fair practices in food trade, taking account of, where appropriate, the protection of animal health and welfare, plant health and the environment” makes explicit mention of a range of parallel goals that must be considered as part of food safety, including environmental health. Use of the precautionary principle is explicitly defined as a guideline for maintaining the safety of the food supply, along with risk analysis. Food businesses such as producers, processors, and manufacturers and retailers of food items are stated as the ideal controllers of food safety because of their proximate knowledge of any risks and appropriate solutions. Traceability is also elaborated as an important prerequisite of ensuring safe food. Article 18 of the regulation reads “The traceability of food, feed, food-producing animals, and any other substance intended to be, or expected to be, incorporated into a food or feed shall be established at all stages of production, processing and distribution.” UK food safety regulation within this European framework is layered beneath EU controls and is predicated on the UK’s 1990 Food Safety Act. The law makes no mention of produce or specific pathogens, following instead the general style of EC regulation in setting goals, definitions and procedures to be followed in the event of a problem. Section 7 of the act names as an offense “rendering food injurious to health” . In cases 4 where food has been sold that is injurious to health, the state can prosecute the provider of that food item under the law. Several defenses are listed which can absolve a food business of criminal responsibility, most notably the defense of due diligence, defined as “a defence for the person charged to prove that he took all reasonable precautions and exercised all due diligence to avoid the commission of the offence by himself or by a person under his control” . A subsequent law, the Food Standards Act 1999, established the UK Food Standards Agency and outlined its role as the controller of food safety within the United Kingdom. Pursuant to these two acts, the FSA has released numerous fact sheets and guidance documents interpreting the 1990 Food Safety Act for owners of food businesses. In a 2009 guide for food businesses, FSA presents examples of situations and actions that the 1990 Food Safety Act would apply to, and explains that the concept of due diligence is designed to protect both consumers and businesses. In their words, the due diligence defense is “designed to balance the protection of the consumer against defective food with the right of traders not to be convicted of an offence they have taken all reasonable care to avoid committing” . The FSA fact sheet Monitoring microbial food safety of fresh produce released in 2010 contains basic information on the names and risk factors for certain food pathogens with guidance for produce farmers in avoiding or reducing the potential for pathogen transmission through food products. The document emphasizes that there are “no statutory criteria for indicator bacteria on unprocessed fresh produce” and thus no specific microbiological targets that are required by law for fresh produce. Key practices recommended for maintaining microbial safety in produce include the use of potable water for irrigation, regular testing of water sources, avoiding the application of raw uncomposted manure on crops that are typically eaten uncooked, and minimizing the degree of contact between irrigation water and the edible portion of crops.In comparison, in the United States, government food safety is managed through a similarly multi-level array of federal, state and local bodies, with requirements that become more specific and enforcement-oriented at local levels.

To adapt direct regulation to new policy arenas and make regulation less costly and time consuming to administer, regulatory variations have appeared that seek to ensure the same outcomes with more efficient use of resources. Modified direct regulation strategies such as Risk-based Regulation and Responsive Regulation retain the basic administrative structures of direct regulation under command-and-control frameworks, while modifying interactions with non-state actors in order to create a less burdensome, more effective and more cooperative regulatory process . In Risk-based Regulation, risk assessments direct inspections and enforcement toward those firms most likely to fail, while low-risk firms enjoy lighter regulation, motivating firms to build a record of compliance . Similarly, Responsive Regulation seeks to understand and resolve barriers to compliance, avoiding the use of enforcement resources to clear up cases of ignorance and misunderstanding, so that they may be used instead only for more serious cases of noncompliance .Process-oriented approaches such as Enforced self-regulation, Management-Based Regulation, Systems-based regulation, Meta-regulation and Principles-Based Regulation aim to control how firms act, rather than directly mandating end results. These styles seek to improve on traditional direct regulation by allowing those closest to the problem to design the solutions , requiring only that solutions be developed internally and put into place. One possible drawback of this approach is that the outcome itself is left uncertain even when regulations function optimally; the possibility remains that firms may be in total compliance with the procedural requirements of this type of regulation, without actually achieving the desired policy outcomes.

Since the 1990s, rolling greenhouse tables many governments have also undertaken efforts to broaden regulatory participation to include a wider array of views and interests . These efforts have been made with the goals of heightening public awareness of regulatory issues and improving the quality of regulation for normative , epistemic , and instrumental reasons. It is unclear however, whether the goals of broadened participation have been, or can be, achieved in practice . However, it can be hard to strike a balance between democratic goals and policy goals, and broadening participation is often expensive. Scholars have also have argued that the success or failure of participative policy projects can hinge on “institutional fit” between the policy process and the beliefs and norms embodied within participation . Nevertheless, co-management may offer the best chance of managing complex social and environmental problems within multi-level governance systems . Although these variations of direct regulation offer improved solutions and more efficient use of regulatory resources, new challenges emerge. Research suggests that risk-based approaches may still suffer from many of the problems of direct regulation because the top-down regulatory style is still not necessarily fully responsive to the needs of industry . Some scholars also question whether these modified approaches truly deliver on the initial promise of regulation by ensuring desired outcomes, or whether they actually result in diluted, less effective regulation .Regulation achieved by non-state entities can take a wide variety of forms, including Information-based Regulation, Private Regulation and Self-Regulation. These forms differ from command-and-control in that rule-making power and enforcement authority are held not by state regulators, but by non-state actors . Self-regulation describes a process where public regulators grant firms the power to define their own regulatory targets and the authority to police their own activities, either individually or through industry associations.

In the food system, these approaches borrow from recent developments in environmental governance that seek to address perceived failures and inefficiencies of state-led regulation by shifting regulatory power to markets and market actors . Enforcement authority in non-state regulation derives from supply chain relationships and from economic concerns, rather than from government. Information-based Regulation seeks to increase the public availability of information about firms’ performance to encourage compliance. In Private Regulation, private actors assume the roles traditionally played by public regulators, by defining targets and directing inspections and enforcement. Private standards typically function alongside and in addition to public regulation but may also act to supplant public regulation where public enforcement is lacking, public standards are insufficient, or where no public response yet exists. One of the most notable benefits of non-state approaches is that they can move more quickly than traditional public regulatory processes, producing timely technical decisions which might have taken longer to emerge from a more accountable, representative public regulatory process involving chambers of government and bureaucratic agencies. This nimbleness can be beneficial when responding to new and emerging threats such as the environmental hazards of new and as-yet-unregulated technologies, or newly recognized public health threats which do not yet have established regulatory benchmarks but for which human suffering might be averted by swift action before such regulation is produced. Although self-regulation and private regulation may seem like the fox guarding the hen house, competition among rival firms can encourage stronger self-regulation as firms watchdog each other independent of public regulatory enforcement, avoiding a race to the bottom. In some cases, private regulation that is viewed as successful or politically expedient may even become hardened into law, generating new public regulation where none previously existed . However, private regulation’s nimbleness and relative lack of bureaucracy can also be an Achilles heel. Whereas governments are accountable to their citizens if their regulatory standards are found to be faulty, no such accountability is necessarily built into privately controlled regulation. The market primarily exerts influence over such standards, and the market can become a vehicle with no driver at the wheel. Private strategies thus reflect the character of their creators; they are as lax or as rigorous, as representative or as mysterious, as complete or as cursory, as the firms and public regulatory efforts that pursue them . If industry associations successfully create ineffective mandatory standards or if firms choose to sign on to those voluntary standards which ask the least of them, the market may experience a downward convergence onto the least effective standards . Self-regulation and private regulation may also be pursued by firms that specifically wish to avoid or to weaken public regulation. Poorly designed or bad faith private regulatory efforts can provide equally poor outcomes.The United States and the United Kingdom have very different agricultural histories, as might be expected due to dissimilar geographies and historical settlement patterns. The history of UK agriculture precedes modern civilization, evolving from a background of early subsistence activities and feudal peasant agriculture. Enclosures of public lands in the early stages of the industrial revolution disenfranchised Britain’s rural agricultural populace, while the role of capitalist production-oriented agriculture expanded to feed growing urban work forces . The current UK agricultural system combines elements of the social and landscape heritage of Britain’s long history of rural family farming with the modern style of capitalist production, within the trade relationships and political linkages of the European Union . Landholdings still often follow historical patterns of family ownership and traditions of land management, even while growing commodity crops meant for international markets . As a consequence of agricultural intensification driven in part by the supply chain activities of powerful food retailers, UK farming has recently seen an increasing reliance on migrant labor beginning since the 1990s . In the US, agricultural histories differ sharply along regional lines, based on timing and character of early post-colonial settlement. California’s agricultural history shares little with that of the UK. California’s relatively recent and highly capitalist agricultural industry did not develop from a history of small-scale, independent family farms, nor from feudal landholdings. California’s native inhabitants did not farm the land, and at no point in subsequent settler history was California host to a small-scale agrarian populace .

Instead, from its establishment around 3 the time of the Gold Rush in the mid 1800s, California agriculture has always been intensive, large scale, market-oriented, ebb and flow rolling benches and dependent on hired labor primarily supplied by migrant and ethnic minority communities, often under extremely exploitative circumstances . Despite the divergent starting points of their agricultural histories, the UK and US both experienced an increase in the public visibility of environmental and public health problems in the late 1800s and early 1900s. A new era of progressive policies followed, aimed at reforming core industrial activities and solving collective action problems in the large-scale production of public goods such as clean water and clean air . In response to a wide array of factors including political regime changes, shifting public opinion, and the rising power of global agribusiness, the approach of the two states has shifted considerably over time. Early in the period of heightened environmental regulation that began among most developed nations in the 1960s and 1970s, the United States was recognized as a progressive leader. The earliest US risk regulation in the realms of environment and food during this time took a precautionary stance that prioritized the public interest and sought to place limits on the activities of industry through ambitious and comprehensive formal regulation on topics including water quality, air quality, product safety, vehicle emissions, and chemical safety. In contrast, although UK regulation had established regulatory bodies dedicated to environmental problems in the mid 1800s, UK environmental regulation during this period was, during this early period, less ambitious than environmental regulation in the US. UK regulatory efforts moved slowly and incrementally, developing multi-sectoral scientific consensus before the drafting of legislation, and relying on trust between industry and regulators rather than enforcement and sanctions.4 Beginning in the 1980s, a wave of neoliberal reforms and deregulation during the Reagan administration changed the tenor of US environmental and public health policy. US risk regulation became more conservative and less precautionary in its approach and more protective of industry, as environmental and public health regulation came to be seen as a tax on industrial economic growth, and US regulators eschewed precautionary policy in food safety partly out of concern that a precautionary stance might present a non-tariff barrier to trade . US environmental law originally referenced precautionary reasoning in decisions around early environmental reforms but Congress and the White House later declared it improper to create policy based on uncertain risks, favoring scientific risk assessment in place of precaution . On this basis, the US adopted ambitious scientific standards developed without formal industry input, requiring mandatory use of the most effective technologies. While some degree of collaboration and flexibility entered the system through the implementation efforts of local regulatory authorities, the basic architecture of the system was built to rein in the activities of industry through the use of stringent direct regulation. Around the same time, the character of UK regulatory efforts in the environmental and public health arena, following the approach taken by the European Commission , retained their focus on trust and consensus, and became increasingly motivated by the precautionary principle. The British style emphasized the evolution of smaller, incremental targets, developed with the cooperation of industry through collaborative site visits and inspections, in a legislative process out of view of the public eye. These targets typically included deep collaborative participation by industry groups and less focus on adherence to rigid standards, allowing a greater emphasis on informal and voluntary participation . By the late 1980s, progress made by the two states on a host of environmental and public health issues showed similar levels of improvement, despite the fact that the two states had approached these regulatory challenges through very different means. The key difference in transatlantic environmental and public health regulation that emerged by the turn of the century was in the attitude of industry toward environmental regulation. In the US, environmental regulation became a highly politically polarizing issue seen by industry as a hindrance to economic growth, while in the UK environmental regulation never became as contentious a political topic, and the relationship of business to government remained focused on compromise and conciliation.In both the US and UK prior to the 1980s, risk management in food and agriculture centered primarily on economic concerns such as commodity production and price supports. Food safety surveillance had existed in both nations since the late 1800s for products such as milk and meat, but food safety was not a leading regulatory focus . Growing awareness of the risk of pathogens in the food supply began to put food safety at the top of the regulatory agenda following the emergence of a new range of public health concerns which focused attention on food production practices and revealed the inadequacy of existing regulatory controls to deal with pathogen threats .

The main advantages of PV include: simplicity of the direct photoelectric conversion technology ; ability to generate partial power under cloudy conditions; and the modular and scalable nature of plant design. Another potential benefit of widespread CSP deployment is a much greater GHG emission offset due to the very high albedo of heliostat fields. However, this resulting change in the albedo of the surface as well as the temperature and evapotranspiration of water at a CSP deployment may have implications for local cloud cover. The extent to which such changes would reduce or increase surface warming requires a regional simulation of the cloud properties, cloud fraction, and cloud duration. While both PV and CSP technologies affect the local environment, the extent in which they do so has not been studied in detail. Nemet estimated that the low albedo of PV panels is responsible for lowering the GHG emission offset by 3% when compared with current carbon-intensive energy scenarios. As the penetration of renewable sources increases, that percentage will also increase, and perhaps to a point of being a significant hindrance to continued GHG emission offsets. Even more important, the local thermal balance effects may cause local environmental disruption in desert areas that rely strongly on the very low soil water content. Midday temperature increases of more than 3 K have been observed in desert PV plants. Conversely, heliostat fields in CSP tower plants are characterized by albedos that are 40-50% higher than the original ground albedo, commercial drying racks thus the GHG emission offset for CSP is much higher in comparison to PV technologies. Locally, a temperature reduction of 2 K and reduced rates of evapotranspiration have been observed as a direct result of the increased albedo of heliostat fields.

This Chapter aims at quantifying the albedo replacement effects of large scale solar farms mainly concerns the temperature anomaly calculated from local radiative balance of the PV and CSP surfaces.Large scale solar farms interact with the atmosphere though land surface albedo replacement. Solar PV farms are highly absorbing while CSP farms are highly reflective when compared to the ground. The spectral albedo of regular surfaces, PV panels and CSP heliostats are plotted in Fig. 6.1, where PV panels have spectral albedo smaller than 0.1 while CSP heliostats have albedo greater than 0.9 in infrared and visible bands. Among the six CIRC cases, surfaces of case 1-3, 6 and 7 have nearly the same albedo while the surface of case 4 has much higher albedo in visible and UV bands, indicating the presence of ice or snow. For the analysis of this section, the regular ground is chosen to be the surface of CIRC case 2. PV panels are assumed to be Si pillar solar cells with spectral reflectance data given by Ref.. The reflection of PV panels is assumed to be diffused. CSP heliostats are assumed to be AgGlass 4 mm Flat glass mirrors, with spectral specular reflectance data given by Ref.. All surfaces are assumed to be oriented horizontally facing the open sky. The vertical profiles of temperature, gases, aerosols and optical properties of gases, aerosols, clouds follow the methodologies presented in Ref.. Note that the effects of PV and CSP farms presented in the following sections are the ‘maximum’ effects, because in the one dimensional radiative model, the entire ground is covered by PV or CSP, but in reality, only a portion of the ground is covered.Atmospheric long wave radiation and solar shortwave radiation are essential components of thermal balances in the atmosphere, playing also a substantial role in the design and operation of engineered systems that exposed to open sky, for examples, cooling towers, radiative cooling devices and solar power plants.

To quantify the spectral thermal balances of the atmosphere and engineered systems, especially optically selective devices, comprehensive line-by-line radiative models are developed to simulate atmospheric long wave and solar shortwave radiative transfer in the Earth – atmosphere system, as well as the interactions between engineered systems and the atmosphere. Firstly, simple parametric models are developed to calculate broadband downwelling long wave irradiance at the surface. Under clear skies, fifteen parametric broadband models for calculating long wave irradiance are compared and recalibrated. All models achieve higher accuracy after grid search recalibration, and we show that many of the previously proposed LW models collapse into only a few different families of models. To account for the difference in nighttime and daytime clear-sky emissivities, nighttime and daytime Brunt-type models are proposed. Under all sky conditions, the information of clouds is represented by cloud cover fraction or cloud modification factor . Three parametric models proposed in the literature are compared and calibrated, and a new model is proposed to account for the alternation of vertical atmosphere profile by clouds. The proposed all-sky model has 3.8% ∼ 31.8% lower RMSEs than the other three recalibrated models. If GHI irradiance measurements are available, using CMF as a parameter yields 7.5% lower RMSEs than using CF. For different applications that require LW information during daytime and/or nighttime, coefficients of the proposed models are corrected for diurnal and nocturnal use. Then, an efficient spectrally resolved radiative model is developed to capture spectral characteristics of long wave radiation in the atmosphere, under clear and cloudy skies. For the non-scattering clear atmosphere , the surface DLW agrees within 2.91% with mean values from the InterComparison of Radiation Codes in Climate Models program, with spectral deviations below 0.035 W cm m−2 . For a scattering clear atmosphere with typical aerosol loading, the DLW calculated by the spectral model agrees within 3.08% relative error when compared to measured values at seven climatologically diverse SURFRAD stations.

This relative error is smaller than the aforementioned calibrated parametric model regressed from data for those same seven stations, and within the uncertainty of pyrgeometers commonly used for meteorological and climatological applications. The broadband and spectral forcing of water vapor, carbon dioxide and aerosols are quantified using the model. When aerosol optical depth equals 0.1 are considered, long wave aerosol forcing falls between 1.86 W m−2 to 6.57 W m−2 . The forcing increases with decreasing values of surface water vapor content because the aerosol bands contribute mostly when the water vapor bands are not saturated. When examining the spatial and spectral contributions of water vapor to the surface DLW, we find, as expected, that water vapor in the nearest surface layer contributes the most, especially in the spectral ranges 0 ∼ 400 cm−1 and 580 ∼ 750 cm−1 . Within the atmospheric spectral windows 400 ∼ 580 cm−1 , 750 ∼ 1400 cm−1 and 2400 ∼ 2500 cm−1 , water vapor above 3.46 km has negligible effect on the monochromatic surface DLW. In some spectral regions, there is a decrease in water vapor forcing because water vapor content in the layers below prevents the long wave radiation from reaching the surface. The warming caused by aerosols mostly comes from the layers below 3.46 km. In a narrow spectral band between 1050 to 1150 cm−1 above 3.46 km, there is a decrease in monochromatic surface DLW forcing, since the lower layer aerosols prevent the radiation from reaching the surface by absorption. Spectral and spatial distribution of irradiation is presented for an atmosphere with surface relative humidity of 65% and aerosol optical depth at 479.5 nm equals to 0.1. First order broadband contributions of increased atmospheric CO2 to surface downwelling flux is found to be 0.3 ∼ 1.2 W m−2 per 100 ppm CO2 increment for different water vapor contents. The broadband reduction of TOA upwelling flux is found to be0.5 ∼ 0.7 W m−2 per 100 ppm CO2 increment. Contributions to the irradiation on the top atmosphere layer and outer space layer come from the surface in the atmospheric window bands, cannabis grow systems from the middle of atmosphere in the water vapor absorbing bands and from the top of atmosphere in the CO2 absorbing bands. For broadband flux contributions, the outer space layer dominates the transfer factors to upper layers but the flux contribution is negligible due to low densities and effective temperatures at that level. For the ground layer, 64.4%, 15.3% and 7.5% of its long wave irradiation comes from the nearest atmospheric layer, the 2nd nearest layer and the 3rd nearest layer, respectively. And the contributions mostly from the four absorbing bands. For all layers below the tropopause, the layer itself contributes the most to its irradiation. For layers above the tropopause layer, the largest contributor to its irradiation is the ground layer. Finally, upper layers above the tropopause contribute to less than 4.8% to the irradiance flux to other layers. Then accurate correlations for the effective sky emissivity as functions of the normalized ambient partial pressure of water vapor for both broadband and seven distinct bands of the infrared spectrum are proposed. The band emissivities are correlated by simple expressions to ambient meteorological conditions at the ground level, and allow for the expedient calculation of cooling power efficiencies of optically selective materials designed for passive cooling or heating. Comparisons between band calculations and line-by-line calculations yield errors that are generally within the measurement uncertainty of atmospheric instrumentation , thus validating the combined approach of high fidelity spectral models with ground experiments taken at diverse micro-climates, altitudes and meteorological conditions.

When clouds are added to the spectral model, the representative cloud characteristics are also proposed as empirical functions for different surface meteorological conditions to guide future modeling efforts. These results enable direct calculation of the equilibrium temperature and cooling efficiency of passive cooling devices in terms of meteorological conditions observed at the surface level. The cooling potential of passive cooling materials is found to be as high as 140 W m−2 for dry and hot conditions without the presence of clouds. But the potential diminishes with increased water vapor content and the presence of clouds, because both water vapor and clouds ‘block’ the atmospheric window for cooling. A Monte Carlo line-by-line radiative model is developed for solar shortwave radiative transfer in the atmosphere, with different surfaces . The local thermal effects of albedo replacements of PV and CSP farms are quantified. Under clear skies, the downwelling GHI is being suppressed by the presence of PV farms while being enhanced by the presence of CSP farms , because of the back-scattering of reflected irradiance from heliostats. The TOA upwelling flux enhancement of CSP plant could be as high as 187%, so that CSP fields are able to cool the surface. Under cloudy skies, the GHI enhancement by CSP is amplified by the presence of clouds because multiple reflections occur between highly reflective CSP farms and clouds. By performing a surface thermal balance, the surface temperature of CSP is 3 K lower than the ambient while the surface temperature of PV or regular surface is more than 40 K above the ambient while under direct sunlight. Under cloudy skies, the irradiance and temperature modification of PV and CSP farms are reduced because the effects of clouds, especially optically thick clouds, dominant. The results presented here strongly suggest the possibility of hybrid solar plant designs that employ an outer ring of PV solar field surrounding an inner heliostat field around the central tower. This hybrid design accomplishes two important objectives: minimization of local changes in temperature and humidity by balancing out the heating caused by the PV field with the cooling caused by the CSP heliostats, and the minimization of DNI variability effects on plant operation through the coupling with the less-variable GHI component absorbed by PV panels. In addition, the thermal balance discussed in this work also allows for the consideration of dual land use, especially under the heliostat field. A raised heliostat field with partial shading may be used for agricultural purposes in desert areas where very few plants could survice without partial shade and lower temperatures and higher humidities. Note that PV panels not only increase downwelling infrared radiation to the soil, but also prevent radiative exchange with the desert sky at night, which in many regions is the mechanism that allows for the formation of dew at night. By considering these different heat and mass transfer mechanisms carefully, novel solar power plant designs may reduce their environmental impact on desertic areas.In 2006, Bagged fresh spinach from the central coast region of California contaminated by Shiga toxin-producing Escherichia coli bacteria with the serotype O157:H7 caused 199 illnesses across 26 US states, and at least 3 deaths .

The mean incidence and prevalence values were extremely low due to the fact that the model simulations assumed that only one super-shedder adult cow and another infected adult cow were introduced into the herd in pen 10 and pen 8, respectively and followed for 10 years. Similar results were obtained when small numbers of infected cows and supershedders were introduced into a herd of 10,000 cows. This indicates that the illustrated results are consistent for small numbers of infectious cows and supper shedders initially introduced to the herd. In the population of adult cows, controls 2 & 4a, 2 & 4b, 3 & 4b, 5 & 4b, 4a & 4b , and all controls combined result in a MAP prevalence of 0.52%. Measures 4a or 4b are common to all the adult cattle effective control measures. Hence an effective way to reduce MAP prevalence in the adult cow population is test and cull of test-positive cattle. However, control 4a was more effective than 4b resulting in a MAP prevalence of 0.61% and 0.98%, respectively. Table 10 shows the number of weekly incidence and the mean MAP prevalence for the most effective triple combination control measures and all of the control measures by the end of year 10 for calves and heifers were 5 & 4a & 4b ; and for adult cows is seen with 3 & 4a & 4b . Simulating all the control measures results in the mean MAP prevalence by year 10 in calves and heifers of 0.009% and in adult cows 1.04%.The simulation results indicate that no single control measure was sufficient to prevent increase in incidence of JD; however, Control 4b resulted in the best single control measure. The most effective combination of binary control measures was produced by controls 4a annual test and cull of adult cows and 4b . The overall risk of MAP occurrence was substantially reduced when test and cull was combined with intensive enclosure cleaning to reduce MAP concentration in the environment.

Particularly, the best triple control measures resulted when combining Controls 3, 4a and 4b, dry racks for weed which combined increased scraping of fecal slurry on solid surfaces in the dairy and /or power washing by 10-fold to reduce the environmental pathogen load, while also testing and culling dry-off cows on weekly basis and adult cattle annually. A farm that employs all control measures or a combination of these three control measures has the minimum risk of JD occurrence. It also has extremely prevalence and incidence provided that the number of infectious cow and supper shedder added to the herd is very small . Finally, it should be noted that these results can be expected if the dairy manager adheres to a cattle movement pattern between pens which maintains a degree of isolation between calves and cows and within the cow population as illustrated in the Cattle Movement diagram. Purposefully moving cattle between pens in a prescribed sequence changes the contact patterns between susceptible and infected cows beyond the assumption of random mixing inherent in infectious disease models. Cattle movement management is integral to the effectiveness of MAP control measures and changes to this system can modify the anticipated success of the control measures.Modeling JD with effects of vaccination has been addressed in previous works . In the present study, we did not investigate the effects of vaccination in our modeling and numerical simulations. Previous research has shown that exposure to MAP vaccines or M. aviumantigens can result in false positive tuberculosis tests, which is a concern for herds in TB free states and specifically those that commonly transport cattle across state lines. Furthermore, no vaccine has been developed to fully protect calves. There is currently no available approved treatment in food animals once an animal has contracted the MAP infection. For such reasons vaccinating against MAP is not widely practiced and hence was not considered in the current model.

In the present work we assumed that the amount of shedding in the calf population does not sustainably influence the transmission dynamics of JD, i.e., γC = 0 for pen 1 . Nevertheless, this could be oversimplifying assumption in cases that the shedding rate is greater than a critical value. Although the simulation result indicate that test and cull can be an effective control measure, there are two major concerns regarding test and cull. First, test and cull result is an immediate economic loss, which may not be recovered for a long period. Second, diagnostic tests to identify infected cows often have low sensitivities and are often costly to apply routinely. Therefore, the efficacy of test and cull substantially varies based on the frequency and sensitivity of the test. There are simulating models and field studies that aim to determine the optimal culling rate in different herds based on the long term profitability of the control measure. However, more data and model simulations are needed to develop reliable, effective and profitable JD control programs. It should be noted that the data related to this study is from California dairies. Hence, the outcomes of current study may not necessarily apply to non-intensive dairy systems elsewhere in the US and the world. However, for dairies that manage cows in housing units and groups similar to the study dairies our findings may apply in terms of effectiveness of control measures and what may be expected in reduction of MAP transmission. Another limitation of the current study as with other mathematical modeling studies and specifically those modeling MAP transmission is the lack of precise transmission rates and other inputs needed by the model. Such model inputs require specifically designed studies that can limit variability and target the specific rate of interest. However, MAP’s chronicity increases the duration of such studies which may translate to increase in cost in addition to prolonged duration of studies and potential for loss of follow up of study animals given other competing risks. To address these limitations, the current study identified several key assumptions that can be justified to utilize ranges of transmission rates from previous works .Investigating the optimal use of the cattle movement model with additional controls can benefit from these findings as the data shows that test and cull strategies seem to give the best outcome for R0. When test and cull is applied in pens 7 through 14 we see the most desirable outcome. While the primary goal of this work was to determine the efficacy of control measures using a NC model applied to JD on dairy farms, such models could also be employed to explore impacts on other animals and potentially applied to other diseases.Antimicrobial resistance is a growing concern for food safety and public health globally. Both humans and animals share similar antimicrobial drugs; hence, the judicious use of antimicrobials by both veterinary and human medicine is important to reduce the risk of AMR in enteric bacteria. The administration of therapeutic and prophylactic antimicrobial drugs in animals can be at the individual animal or at the group level. Improper or excessive use of antimicrobials can lead to the development of AMR and multidrug resistance in dairy cows and calves, which could potentially result in the accumulation of bacterial AMR genes within livestock and throughout the farm environment. Modern dairy production systems can be composed of multiple inter-connected cattle production stages, with each stage characterized by unique management practices. Production status, disease conditions, and health status within the cattle groups, and patterns of and governing regulations for antimicrobial usage vary with these stages of production. The distribution of AMR genes in dairy farm settings has not been fully characterized due to the complexity of resistome in dairy production systems and different bacterial communities for different stages of production throughout the farm environment.

According to USDA’s Animal and Plant Health Inspection Service, antimicrobial use in dairy cattle production is classified as three stages of dairy production consisting of preweaned heifers, weaned heifers, and cows and treatment of digestive problems, respiratory infections, mastitis, lameness, and reproductive problems. In general, commercial racks the most frequent antimicrobials used in dairy cattle are tetracyclines, beta-lactams, cephalosporins, and florfenicols. Excessive selective pressures with high antimicrobial concentrations of relevant enteric bacteria can result in a high probability for selection, survival, and dissemination of AMR genes in the environment . Although AMR genes are frequently detected in bacteria from dairy cattle feces, far less is known about the relative abundance of resistance in cattle at different production stages. These knowledge gaps of the ecological connectivity of AMR reservoirs in relation to their microbial communities, and AMR gene transmission pathways within and between dairy cattle at different production stages hamper our efforts to minimize the emergence and persistence of AMR. Whole-genome sequencing and bio-informatics approaches are increasingly used to systemically characterize AMR genes in bacteria from livestock including dairy cattle. The State of California has been the primary dairy producer in the US since 1993, contributing to 18.5% of US milk production. In 2017, dairy cows in California accounted for greater than 20% of the entire dairy population in the US. The overarching goal of this study was to characterize AMR genes in commensal bacteria from cattle at different production stages to generate data that can support future efforts to target AMR control efforts on the farms. Our objectives were to identify AMR genes in Escherichia coli and Enterococcus spp. from cattle at different production stages, contrast AMR phenotypes with the presence or absence of these bacterial AMR genes and identify production stages that have higher risks of spreading AMR genes within the farm environment.The purpose of our study was in part to characterize the overall resistance profile of fecal E. coli and Enterococcus from cattle at different production stages. Based on the resistance genes detected from the ResFinder database , genes conferring resistance to tetracycline, sulphonamide, and aminoglycoside were the main resistance genes in E. coli. This finding was similar to a previous study of AMR in E. coli isolated from dairy cattle, which found E. coli was mostly resistant to tetracycline followed by florfenicol , ampicillin , and chloramphenicol. For Enterococcus spp., resistance to macrolide was the main resistance gene identified in the ResFinder database . In terms of resistance genes identified from the CARD database, 100% of E. coli isolates had genes resistant to over 15 classes of antimicrobials, and 77.6% of Enterococcus isolates had genes resistant to three classes of antimicrobials. Due to the differences in availability and settings of genes between the ResFinder and CARD databases, it was not surprising that resistance genes in E. coli and Enterococcus identified from the two databases were not identical. Interesting, the two databases were consistent in the detection of tetracycline, aminoglycoside, and phenicol as major resistant genes in E. coli and macrolide and aminoglycoside as major resistant genes in Enterococcus. With respect to the major resistance in E. coli and Enterococcus , tetracycline is one of the commonly used antimicrobials in food animal production in the US and Europe, frequently for digestive conditions. Tetracycline is normally used for the treatment of respiratory diseases in food-producing animals in the US. Tetracycline-resistant bacteria, especially non-pathogenic or commensal bacteria, may play a major role as bacterial reservoirs for AMR and MDR, both within cattle populations and for the general dairy farm environment given the ubiquity of manure in these production systems. In general, macrolides and lincosamides are used for the treatment of bacterial infection, especially in mastitis cows, and for growth promotion in food-producing animals. Macrolides are also used in combination with aminoglycosides to treat mastitis in dairy cattle in some European countries, while lincosamides are mainly used in the US in dairy cattle production. We did not collect information on antimicrobial use for this study;hence, we were unable to assess the relationships between the occurrence of AMR genes and antimicrobial use on the farm. However, many studies have indicated that the use of antimicrobials in food-producing animals including dairy cows can lead to increases in AMR and MDR bacteria on livestock farms. In future studies, it would be interesting to further investigate the relationships between AMR and patterns of antimicrobial use at different production stages.Enterococcus spp. are known to cause mastitis in dairy cattle. A previous study revealed that Enterococcus spp. isolates from fecal samples from 122 dairy cattle operations were resistant to lincomycin , followed by flavomycin , and tetracycline.

Starting in school gardens, students today can be educated and prepared to lead the radical and climate-beneficial food system transition of tomorrow.Stepping back and looking at on-the-ground realities across the contexts of study presented in this dissertation, there are numerous examples of individuals and organizations who are theoretically on the same “team” when it comes to goals of mitigating climate change and advancing social equity, and yet engage in intense debate in their activities, rhetoric, and interactions around how to achieve these goals. Vegetarians calling out those who eat grass fed beef on Lopez for contributing to negative climate impacts; urban farmers with different visions and theories of social change choosing not to work together to advocate for policy change; educators who promote a more factual teaching of climate science arguing with those who aspire to a more holistic, socially grounded form of climate education. This antagonism among those working towards shared goals can be seen playing out on a global scale as well: environmental movements that do not adequately incorporate environmental justice, indigenous land ethics, and communities of color; climate activists who disagree about how best to reduce emissions, who bears primary responsibility for action, or whether to directly confront entrenched institutions and power structures; new farmers who glorify small-scale agriculture without acknowledging that pathways to farm ownership are not equitably available to all groups; food systems researchers who demand immediate revolution pitting themselves against those who argue for a more gradual approach to change from within the system. Recognizing these rifts as well as the reality that the global food and climate system is currently at a critical juncture, Anderson articulates a vision for a “healthy, vertical grow systems sustainable food system” that joins with other visions, key to any successful social movement.

Confronting the dominant food system and greenhouse gas emitting global economy can only happen through a broad-based social movement where the majority of people across race and class lines can see themselves held in a common vision. Social movements, according to Saru Jayaraman , by definition contend directly with the centers of power; they do not avoid direct confrontation in seeking to change the status quo. Remembering as Obama repeatedly told Americans that “there is more that unites us than divides us,” there is work to be done reconciling disagreement among food and climate researchers, practitioners, and activists in order to confront the forces of the status quo: corporations, bureaucracy, and fossil fuel interests that prevent progress on issues where there is wide public support, in effect subverting democracy. For example, there is an opportunity for alignment among those who choose not to eat meat for environmental reasons and those who choose to eat grass fed meat in opposition to a common enemy: concentrated animal feeding operations . CAFOs contribute dramatic negative impacts to the environment and human health, beyond the footprint of their feedlots and extending to the vast acreages used to grow synthetically fertilized, monocropped grains for animal consumption. Imagine if much of this acreage was converted to growing diverse requirements of a plant-based diet for humans, and some was allocated to grass fed meat operations . Cows contribute to pasture restoration and can lead to net carbon sequestration through aerating and adding manure to grassland soils. Furthermore, the manure from some grass fed beef operations contributes to creating high quality compost that enables organic vegetable production. There is a possible convergence between disparate food systems activism that requires further research and participatory collaborations among food scholars, consumer groups, farmers, and ranchers.

Education systems can contribute to reconciling some food systems debates as well: well-crafted food and climate curricula can enable collective action by uncovering shared motivation among different actors, organizations, and individuals.The chapters of this dissertation articulate the role of small farms and farm-based education in providing social-ecological and educational benefits to communities. Small farms are involved in educating youth, beginning farmers, and the general public about the food system as a whole, and its potential to transform into a climate-beneficial system that promotes rather than destroys human health. Many small farmers are on the front lines of pioneering climate friendly growing practices, gathering data on these practices, and educating their communities about why they are doing what they’re doing. These small farmers are leading farmer-to-farmer workshops, hosting tours of their farm for the public, partnering with researchers and applying for soil health grants, and engaging with schools in their communities to provide both farm-based education and nutritious local food for school lunches. How can the work of small farmers be supported and scaled up? They are undoubtedly positive community influences and providers of essential services . But when so much is stacked against them in terms of marketing channels, research and technical support, land access, and political influence, how does small scale farming come to be an occupation that more people are drawn to, and one that is economically viable? According to a recent publication , less than 1% of the USDA Research, Education and Extension budget is allocated to support agroecological and organic farming operations . In the policy realm, change is needed in budget allocations, incentive structures, and subsidies in order to truly scale the food system transition work that small farmers are leading .

Looking to the technology and infrastructure arena, farmers in the cases presented clearly state that additional tools, equipment and facilities appropriate for processing and transporting smaller quantities of food items over shorter distances are also integral to allowing food systems to relocalize.Small farmers in developing countries are producing 70% of the world’s food supply on 30% of the available agricultural land , but some regions of the world are inherently more difficult places to produce food than others, and some degree of large scale farming and global distribution will be necessary to support a growing global population and buffer against adverse conditions in particular locations. Distribution channels must shift in order to allow food to more easily reach the people and places most in need, and export-oriented economies must refocus on feeding their own people—these are areas for future research and civic engagement. This dissertation is not arguing that all farms must be small farms, nor is it a prescription for how or what food should be grown in each region of the world. It is also not arguing that small agroecological farms are “the future of food;” many competing visions exist for how food should be produced in the future, from controlled-environment agriculture to lab-grown meat to renewed attention to soil health. My cases do not speak to every part of the world, but rather are nested within and illustrative of larger theoretical frameworks. I am not arguing for the complete abandonment of a global food system to be replaced with entirely small organic farms serving local communities all over the world. Rather, I am arguing for the valuable social, ecological, vertical grow rack and educational role small farmers are playing in addition to producing food—a role that current industrial production farms are not able to play—and arguing for political-economic system shifts that allow small farms to co-exist with larger farms and “scale across” as a vital form of human connection to the food system. This role would potentially be lost with the disappearance of small farmers. This dissertation adds to the available data on the benefits and strengths of allowing food systems to relocalize in certain contexts where this is desirable or under way. Some see an inherent benefit in local choice and sovereignty over resource production and consumption, whether that resource is energy , food , or forest . A bio-regionally appropriate approach to food production is analogous to bio-regionally appropriate energy generation in that both recognize the value of doing what makes sense in a particular place. Where it is warm, grow heat-loving plants: where it is windy, install wind turbines. Drawing on Amory Lovins’ “soft path” approach for the American energy sector,a soft path for food systems would entail regionally tailored production systems matched with appropriate technology for processing and distributing food products from areas where there is plenty to areas where food is scarce, starting from within the region. This bears similarities to distributed energy resource planning that incorporates batteries alongside generation technologies to store energy when it is plentiful and provide energy in times when demand is high. In arguing for relocalization of the food system and for reconnecting people to their food sources, this dissertation offers an indirect critique of the “feed the world” narrative prevalent in much food systems research.

Many food related research articles, including materials promulgated by the U.N. Food and Agriculture Organization , begin with a statement such as, “in order to feed a population of 9 billion by 2050, the world must double its current rate of food production, even as climate change threatens our ability to produce food at current rates.” Statements such as this overtly ignore the reality that the world is currently producing more than enough calories to support the global population, yet some people have too much and others do not have enough to eat, and up to 40% of food that is produced in developed countries such as the United States is ultimately wasted . The global food system is producing a glut of grain and commodity crops often used for animal feed or for bio-fuels in some cases, focusing on profits rather than feeding the hungry. In the United States, almost 90% of total cropland acreage is planted with just three crops: corn, soybeans, and wheat , much of which is used for non-human consumption . There is a food distribution problem in the U.S. and globally, in addition to a food production problem , rooted in systems of inequality and legacies of racial and economic discrimination. However, this dissertation does not directly engage with this debate, as it does not conduct the national or global modeling of land use requirements for agroecological production systems and does not attempt to average or quantify amounts of food produced per acre from such systems. Reconnecting people to the simple yet powerful act of growing food, the production element of the food system, has the potential to unlock advocacy for change in other system elements . Those who produce food or have knowledge about farming/food production are more likely to seek out shorter food supply chains and local distribution points, as well as less likely to waste food, knowing the time and energy that went into growing it in the first place. Reconnecting people with food production and thus, the food system as a whole, is part of the essential social-ecological and educational value that small farms provide to community. Recalling the work of Ostrom and SES scholars, it is clear that the policy work required to govern a return to a food production “commons” in some local arenas will be contentious, and will need to overcome controversies and tensions among different food system stakeholders. Some changes to local food systems may create winners and losers, favoring farmers over low income consumers, or farm owners over land lessees. It is the role of food systems-informed policymakers as well as ordinary citizens to consider trade-offs and synergies, and seek to make the best possible decisions for their local, regional, or state contexts, while continuing to pay attention to and advocate for appropriate national shifts in funding, subsidies, etc. . The work will not be easy and will benefit from further research exploring effective as well as ineffective policies geared towards facilitating sustainable local food system governance.While my dissertation does not address explicit strategies for greening and improving the sustainability of the industrial food system, research in this direction is urgently needed. It is not realistic to expect the dominant food system paradigm to disappear overnight, replaced by small scale agroecological farms. Therefore, efforts to increase water use efficiency, reduce runoff laden with nitrogen fertilizers and chemicals, reduce fertilizer, pesticide, and herbicide application rates, reduce nitrous oxide and methane emissions, and increase biodiversity on large industrial farms are important areas for research and extension. Examples abound in the work of Don Cameron at Terra Nova Ranch, pioneering the practice of on-farm water recharge by flooding his fields in winter to recharge depleted groundwater aquifers; David Doll working in the capacity of Farm Advisor in Merced County to promote practices such as Whole Orchard recycling to convert orchard biomass into a valuable soil building resource; and Gabe Brown of Brown’s Ranch in North Dakota, reducing the use of herbicides and pesticides as he converts hundreds of acres to no-till farming and allows a healthy community of diverse soil microorganisms to control weeds and pests.

Produce from each farm site reaches approximately 250 people per week on average during the peak growing season, or approximately 7,000 people from all surveyed farms. Customers reached is moderately correlated with total revenue suggesting a growing impact on CFS as farms access additional income. Farmers reported diversified distribution methods including volunteers harvesting and taking food home , on-site consumption , on-site farm stand distribution, CSA boxes at pick up sites, and volunteers delivering produce directly to distribution sites . Some gleaning and second harvesting occur at urban farms and gardens with potential for growth given reported “unharvested” and “wasted” food percentages. Backyard produce is also exchanged through crop swaps and neighborhood food boxes . Eight operations reported having access to a refrigerated truck for food deliveries, and two are willing to share their truck with other farmers. There is no universally used or city-organized process for distributing produce off of urban farms and into the community, yet there exists great interest in aggregating produce or distribution channels , an unrealized goal of urban farmers in the East Bay. All of the food system stakeholders involved in our study are working towards transformative food system change, focused on increasing equity, food security, and access to healthy, locally sourced food. See Box 1 for a description of one of the non-farmer stakeholders engaged in the food recovery and distribution system, vertical growing systems who has recently established an aggregation hub to serve as a network for reducing food waste and channeling excess food in the urban community to those who are food insecure.

Farmers in our study stressed the importance of producing non-food related values on their farms, including education and community building. One farmer in particular emphasized their organization’s mission of “growing urban farmers growing food,” or teaching other people how to grow a portion of their food basket, thus unlocking food sovereignty and food literacy while increasing healthy food access. Another respondent reported that their farm is “highly desirable for adults with special needs that need a safe place to be outside,” echoing respondents who point out the intimate connection between food and health . Farms frequently reported hosting educational and community-building workshops, cooking and food processing demonstrations, harvest festivals, and other open-to-the-public community events enhancing the resilience and connectivity of people, communities and ecosystems. Social networks emerged as an important theme for enabling the establishment of urban farms and sustaining operations through social connections between urban farmers and other food justice and health advocates. One farmer described food production and access from a human rights perspective, stating: “We live in a society that is based on profit not human needs. We believe access to healthy organic local food should be a basic right for all of the people.”Farmers identified three primary challenges: revenue, land, and labor inputs. Half of all respondents reported farm earnings of $1,500 annually or less , and all four operations receiving over $250,000 in annual revenue are well-funded non-profit operations. Regardless of for-profit or non-profit status, most farms reported multiple sources of revenue as important to their continued operation , with an average of 3 revenue streams per farm. All non-profit farms reported multiple revenue streams except for three, who were sustained entirely by either board donations, membership fees , and grants. The most important revenue sources for non-profits include grants, grassroots fundraising, and unsolicited donations rather than sales.

In addition to these monetary sources, all farms reported receiving substantial non-monetary support , which adds to the precarity of operations when these informal support channels disappear.Land tenure arrangements range from land accessed without payment through contracts with City or School District officials, to arrangements where a token fee is paid , to more formal leasing arrangements at the utility-owned Sunol Ag Park, where land tenants pay $1000/acre/year for their plots, ranging from 1-3 acres. Only five of the respondents owned their land , representing a mix of for-profit and nonprofit operations . Challenges around land access, security, and tenure were the most frequently occurring theme in the survey long response and interview analysis process, including consensus that land access is the largest barrier to scaling UA in the East Bay. The cost of labor, and relatedly, access to capital and grant funding to pay living wage salaries, were also extremely significant challenges identified by survey respondents. The majority of respondents stated that most of their labor is volunteer rather than paid, with nonprofit respondents reporting this more frequently than for profit enterprises . The maximum number of paid staff at any operation is 20 , while the average is 4. Many farms reported the desire to be able to hire and pay workers more, but not having sufficient revenue to accomplish that goal. Annual volunteer labor participants on farms ranged from 0 to 1542 with an average of 97 volunteers,representing a significant public interest in participating in local food production. Not surprisingly, amount of paid labor and total farm income are positively correlated . However, volunteer labor is also positively but more moderately correlated with total farm income . Farmers also expressed a desire to enhance race and ethnic diversity in terms of labor participation, with 16 farms indicating interest in learning how their farm can better address racial justice and equity through operations and participation.

The farmers in our study acknowledged many challenges facing urban agriculture, stemming both from the high economic costs of production and land rents, and insufficient monetary returns from produce sales. They also framed these challenges through a food justice lens, arguing that the current political economy does not fully compensate farmers for the social-ecological services provided from their farms. Farmers articulated many solutions that could improve the viability of their farm operations including: conversion of city parks into food producing gardens with paid staff, government and institutional procurement goals for urban produced foods, municipal investment in cooperatives or other community based food production , and establishment of aggregation hubs and distribution infrastructure.Our survey results describe a highly diversified East Bay Agroecosystem comprising urban farmers and other food system stakeholders that are growing food as well as food literacy, civic engagement, connectivity, and community. Applying an agroecological lens to interpret our findings of East Bay urban agriculture operations reveals the many agoecological practices farms have long been engaged in, as well as the important distinctions of UAE that still need to be explored, and specific threats to agroecology in urban areas. Pimbert suggests that “agroecology’s focus on whole food systems invites urban producers to think beyond their garden plots and consider broader issues such as citizens’ access to food within urban municipalities and the governance of food systems.” We argue that applying an agroecological lens to the urban context also invites researchers and urban planners and policymakers to think beyond garden plots and singular benefits of food production, to consider these sites as part of a larger agro-ecosystem with synergistic social, cultural and ecological dimensions. We reference the 10 elements of agroecology to illustrate the dynamics of how these elements manifest in practice in this urban context.All of the farms in our survey follow agroecological production practices which include a focus on building soil health through, most commonly, cover cropping, compost application, and no-till practices. These practices produce synergistic effects of adding fertility to the soil through organic matter amendments and boosting water holding capacity. Soil building practices are a response to the impetus to remediate toxins present in urban soils , a prerequisite to intensive cultivation and unique consideration of the urban farm environment. Overall, production practices on our urban farms seek to conserve, protect and enhance natural resources. Our survey respondents described numerous strategies for enabling diversified, intensive production of fruits, vegetables, and other agricultural products. These strategies span both short and long-term, from planting in raised beds with imported soil, to building soil health in situ via heavy applications of compost, manure, plant growing rack and cover crops for several years leading up to vegetable crop production. There is a growing interest in using no-till practices, which are among the suite of practices associated with “carbon farming” for enhancing soil carbon sequestration .

This illustrates a synergistic opportunity for urban food policy and urban climate policy, showing where urban food production and city Climate Action Plans 18 can converge and generate mutual support . Farmers are also engaged in innovative resource recycling and resource use efficiency and other strategies to enhance resilience such as installing rainwater catchment systems in concert with swales and soil health practices to optimize use of this scarce resource. Farms are planting native flowers and shrubs to attract beneficial insects, rather than purchasing chemical inputs for pest management. From a city planning perspective, the impetus to remediate stormwater overflows and maintain corridors for essential pollinators are two priorities that can be met through incentivizing and planning spaces for UAE.East Bay urban farms reflect multiple scales and forms of diversity including agrobiodiversity, organizational and participant diversity, diversified sources of capital, labor and land arrangements, as well as diversified modes of exchange. Diversity among operations technically doing the same thing- growing food in cities- signals the fluid, flexible, peripheral, and at times revolutionary nature of urban food production spaces, which may conflict with or resist the institutional, political-economic status quo . Urban farms rely on diverse revenue streams from their diversity of activities beyond sale of produce. These activities, including educational services and community events, are important to elevate in policy conversations. Valuing and therefore protecting urban food production spaces requires thinking differently about them in a context like the San Francisco Bay Area.One stakeholder suggested considering urban farms as museums, providing essential cultural and educational offerings to city residents . The quality of the food and the value of the education, health, and community building, are strong arguments for including urban farms in an urban-agroecological framework for city planning and efforts to improve CFS. The diversity of land access agreements and labor sources used by urban farmers in the East Bay underscores equity considerations in urban agroecological transitions. Even 50% of the for-profit enterprises reported relying on volunteer labor, speaking to both the precarious economics of running an economically viable for-profit food production business in the city, and the interest among young people and aspiring farmers in gaining agroecological cultivation skills through arrangements where they donate their labor free of charge. Volunteer labor substitutes for revenue to a certain degree, allowing farms to exist and distribute food informally without needing to generate much revenue or provide many jobs. In the UA literature, reliance on volunteer labor comes under criticism for being a product of the “neoliberal city,” where responsibility for action falls to the individual rather than the state, and the equity concerns around who is able to volunteer their time are problematized . By reporting the common use of volunteers on East Bay urban farms, we do not seek to promote or valorize this practice, but rather recognize it as a necessary interim step occurring in our study context in the absence of dramatic local government intervention or radical reforms to address community food insecurity: those who are willing and able are participating through civic engagement in urban farms to produce, harvest and distribute healthy food to those in need. Many volunteers are retired or recent graduates, seeking opportunities to contribute meaningfully to their communities. The volunteers we have communicated with generally report positive experiences and enjoyment from their time digging in the soil. Despite this, it is vital to acknowledge that the goals of food sovereignty underlying agroecology, especially the Nyéléni declaration, imply that food producers need to be able to earn a living to secure other basic needs, farm revenue is needed to sustain operations, and community members need to be able to pay. However, in cities where wages are stagnating relative to the cost of living and the right to remain is under threat to rising property values and rents , affordability of food impacts growers and consumers alike. The critique in the literature against charity in the food system is that the dependence on charitable donations in the food space are a patch for the destructive neoliberal state, which has shifted the burden of social well-being onto the nonprofit sector. Heynen, critiquing the depoliticization of hunger and poverty through charity, asserts that “[c]harity, however well intentioned, has become the means by which the welfare state was successfully rolled back” .

In Taylor and Lovell’s analysis, they attempt to quantify production and spatial area of urban agriculture using both manual interpretation of high-resolution images and ground-truthing data from walking the city. They find production from residential gardens to be a threefold increase in food production over community gardens, and find both home and community gardens to be highly unevenly distributed: most home gardens are in Chinese and single-family-home neighborhoods, and most community gardens are in the south and west side due to higher land availability, meaning many urban core, low-income census tracts lack access to community or residential gardens. They advocate for better networking of community garden sites to increase access, strategic location of future community gardens among neighborhoods in need, and an emphasis on creating and encouraging home gardens as a key food production strategy available to many city residents. Mack et al. find that 68 urban gardens in Phoenix, AZ are currently serving just 8.4% of “food desert” residents, and through spatial analysis, 53 gardens sited strategically could serve 96.4% of such residents. From these studies, it is clear that UA projects are not necessarily occurring where they are most needed to increase food security. When it comes to spatial analyses, “while a macro-level quantitative study of the potential in terms of land availability shows that it would be feasible to grow the basic daily vegetable needs for the urban poor in the United States, mobile vertical grow racks current evidence from urban farms located within lower-income communities shows that such farms are not necessarily feeding the communities in which they are located,” due to a variety of factors including cost of produce and cultural desirability .

Barriers to access are not just due to geographic distance, but rather an array of intersecting factors including the high costs of some urban produced foods, especially from commercial or for-profit operations. Fresh, local produce from vertical or rooftop farms such as Gotham Greens , Plenty Higher Ground Farm , Freight Farms or AeroFarms are often sold at a premium to restaurants and grocery stores, and thus unaffordable to low income households . Despite claims that vertical farms can “feed the world in the 21st century” , it remains to be seen if vertical farms can address food access and food justice. Such farms are often following a corporate food system model of profit maximization and resource use efficiency, subscribing to capitalist logics rather than alternative, social-justice-oriented practices. Among for-profit farms, “the few profitable operations tend to be those selling to high-end restaurants and consumers, not to lower-income residents” . The cost of food, especially healthy fresh produce, is often in tension with other high costs of living in urban areas , causing low-income residents to become dependent on emergency food services and food pantries. This intersects with poor nutrition and diet-related diseases- according to the Alameda County Community Food Bank Hunger Study report, “food is often the most critical factor in our clients’ health”, and 40% of clients are in fair or poor health . Food banks and food pantries fill important “access gaps” that urban farms could better supplement or address if cost of urban produced food was made more affordable, or through donations to food banks . Low-income households can circumvent the high costs of urban produced food from commercial farms by establishing their own backyard gardens , or adopting plots in community gardens. Through direct participation in UA, in particular food insecure individuals can offset significant percentages of fresh vegetable expenditures , and enhance food security through improved healthy food access .

Access via UA participation is certainly enabled when urban farms and gardens are physically proximate to low income neighborhoods, demonstrating the intersection of cost and geography in expanding access. There are abundant examples of non-profit farms that give food away for free or at reduced rates , yet there is little scholarship on the consumption or impact of donations/discounted offerings specifically.High costs of land and development pressures also play a significant role in limiting access to both farming and locally-produced foods, as seen in studies of Chicago, New York City, and the San Francisco Bay Area . High cost of land prevents community gardens from being established in the urban core in Chicago, leads to hundreds of community gardens in NYC slated for redevelopment annually, and drives gentrification and displacement in neighborhoods around urban farms. Land tenure insecurity directly contributes to lack of access as many urban farms formerly serving minority and immigrant populations have been forcibly closed due to development priorities for privately owned lots . A recent article on land security indicators among California urban farmers showed that farms with higher land security also had “more financial and institutional support, and are located in census tracts with higher economic opportunity” . This highlights the necessity of devoting publicly owned lands to urban agriculture in low income and minority neighborhoods, as private lands are highly vulnerable to development pressures, thus jeopardizing any gains realized by social justice oriented urban farms. In contexts where urban farms strive to provide living wage jobs and career or educational opportunities for low-income communities, youth, or formerly incarcerated individuals, it is often challenging to also provide food access to these same communities. Unless significant grant funding or donations exist, the goals of boosting food security are in tension with capitalist economic realities to pay living wages and sell the product at below-market costs . This speaks to the “unattainable trifecta of urban agriculture,” that is the idea that UA can simultaneously achieve community food security, provide on-the job training and fair living wages, and generate revenue through sales to cover these costs without substantial outside investment , as well as the tension between farm security and food security .

In examples such as City Growers and Higher Ground Farms in Boston, organizational efforts to provide jobs and job training lead to marketing of produce to high-end restaurants, retail establishments, farmers markets, and CSAs at prices unaffordable to food insecure households .A fourth important food access barrier cited in the literature relates to cultural acceptability and nutrition education, widely accepted as part of food security definitions . Access to culturally appropriate foods is known to be an important factor , yet little is understood about the effects of urban farms growing culturally relevant foods and its relation to food access. More qualitative research is needed on the cultural acceptability of urban produced foods and how that might correlate with improvements in access. There is increasing evidence of the importance of culturally relevant educational materials around nutrition, food literacy, and culinary skills for improving access and actual consumption of healthy, fresh, urban-produced foods among low income, minority, or immigrant households . Culinary skills and food literacy are becoming focal points of school garden programs , and innovative organizations such as the Green Bronx Machine show how urban agriculture embedded into high-needs schools can directly improve food education, which translates into increased access and consumption . Additional research is needed to quantify the impact of educational school gardens on community food security. Recent urban foraging literature is exploring stewardship practices and culturally relevant products gathered by foragers in cities around the world, as well as the sociocultural benefits that result . From Mien immigrants gathering dandelion bud-shoots in urban parks , to informal urban foragers helping maintain trees and parks in Seattle, WA ranging in age from 23 to 83 , to the value of edible weeds urban foraging is an activity that recognizes certain agroecosystems as “commons” for public access and management. Urban forest justice scholars “recognize the rights of local people to have control over their own culturally appropriate wild food and health systems, including access to natural resources and to the decision-making processes affecting them” . The potential to address food insecurity with foraging and gleaning activities is being explored by organizations such as Ample Harvest and The Urban Farmers in Northern California; Ample Harvest’s online platform supports over 42 million backyard and community gardeners in ending food waste by channeling excess produce to 1 out of every 4 food banks across the country . While some food justice scholars conclude that current shifts toward local, organic, weed growing systems sustainably produced foods are only accessible and affordable to those with higher economic means “or at least the cultural cachet necessary to obtain such foods through barter, trade, or other means of exchange” , the examples above illustrate successful alliances of food justice advocates and local government working to enable sustainable, healthy food access for all urban residents. Through strategic planning and policy design, it may be possible to move beyond ad-hoc successes in linking urban agriculture with food access. The articles reviewed in this section provide a mix of academic studies, theoretical arguments, and policy literature. Additional empirical evidence and longitudinal studies are needed to demonstrate the ability of UA to significantly improve nutrition and food insecurity among urban low-income households over time. Furthermore, consumer preference surveys of urban produced foods are a conspicuous absence in the reviewed access literature. We turn next to food distribution, and the question of how urban produced foods get from the farm to the consumer through various distribution mechanisms.What does the literature tell us about the distribution of urban produced foods?

While many articles reviewed mechanisms for channeling rural or peri-urban produced foods into urban areas to increase fresh produce access , very little scholarly data exists on the distribution and accessibility of urban produced foods, and what does exist is largely under-theorized. In fact, very few sources reviewed explicitly name “food distribution” as a key term. Urban agriculture remains a relatively small, yet important percentage of the larger food distribution system in cities: “few, if any, urban agriculture projects, are intended to replace traditional food retail or would claim to lead to food self sufficiency for individuals or for cities” . As such, very little is understood about where and how urban farmers distribute their food including modes of transportation delivery, either individually or in aggregate, and to whom . It is important to focus on the means through which food produced by different types of farm operations travels from farm to consumer, and the processes through which that food is exchanged , as this directly impacts access and consumption. The scholarly literature as well as media stories describe various modes by which fresh produce is distributed in the city to address fresh food access including both formal and informal distribution channels . Applying a distribution lens to the existing literature yields similar results to the food access analysis in that several articles theorize idealized distribution systems, showing the capacity of hypothetical urban and peri-urban farms to supply distribution networks that meet most urban food demands . Others highlight barriers and challenges farmers face in practice around distributing their produce to those in need while maintaining their operations . None, in our search, focus analysis on distribution flows of urban produced foods across a city. Rather, a more common focus is on which distribution channels are best for getting produce, not necessarily urban produced, into the hands of food insecure households or residents of “food deserts” . Is it a corner store, a large supermarket, or small local farm stand within a mile radius that households need to access fresh produce?In the case of corner stores, several studies have built on analyses of the prevalence of corner stores and liquor stores in low-income census tracts and endeavored to study the effects of providing fresh local produce in these stores otherwise carrying largely processed foods and sugary beverages. Results have been mixed, with some cases of pairing urban farms with corner store retailers yielding increases in sales of fresh produce , but others showing no increase and even resistance from corner store operators who feel that this produce will not sell and therefore become a waste disposal issue . Small neighborhood groceries and mobile markets were found to be promising distribution outlets for expanding access to fresh produce in some Oakland, San Francisco, Erie County NY, and New Orleans communities . However, they are unevenly distributed and conflicting in terms of providing culturally appropriate foods to all minority groups . In most cases, additional trust and consumer education as well as lower costs and better infrastructure are needed in order to make small groceries and corner stores reliable, accessible, affordable, and sustainable in their operations over the long term.