Aquaponics technology has recently been offered as a good option for sustainable food systems among small-scale farmers, particularly those seeking an organic production or dealing with land quality constraints, such as urban farmers. However, there is a lack of empirical evidence for the capacity of small farmers to adopt the technology. The unique requirements of aquaponics may create technical, economic and even cultural constraints and opportunities. This paper uses empirical evidence gathered with small-scale farmers in São Carlos, State of São Paulo, Brazil, to present the capacity of adoption for the technology, including possible limiting factors and incentives for farmers. The study conducted interviews with owners of ‘agriculturas familiares’ (Portuguese for small family owned farms) within 30 km of São Carlos. The interviews revealed that there is widespread interest in the potential profitability of aquaponics systems, significant interest in environmentally friendly practices, familiarity with organic production and hydroponics and a large base of agricultural knowledge in the community that can drive adoption. However, lack of initial financing, limited human power and concerns about product placement were significant barriers to adoption. For settlement farmers (those working on land formerly abandoned) poor soil quality and water scarcity are key issues that could be alleviated by the technology. The city of Sao Carlos present program for purchasing specific types of products from these farms could be used as a model for increasing aquaponics adoption and relieving success concerns.

Faced with a society that demands the reduction of negative environmental impacts of agriculture while producing high-value, healthy food for local and export markets, Argentina is currently in a debate on the alternative paths toward sustainability in agricultural production. Argentina is ranked second in the world in terms of land under organic certification. Extensive sheep production in Patagonia natural grasslands accounts for most of this area and harvested organic area remains a very small fraction of total harvested land (0.6%). This paper aims to contribute to the discussion of opportunities and limitations in organic farming as an ecological intensification alternative for Argentina's Pampas. A case study was conducted on Pampa Orgánica Norte. This is a group of nine organic farmers that manages field crops and livestock-certified organic production. Farmers interviewed in this study considered different criteria including economic and environmental attributes when choosing to produce organically. However, the main drivers for conversion to organic production are related to environmental factors, in particular ecosystem protection. The main limitations in organic production are related to crop management practices, primarily weed control. To achieve the goal of increasing organic production a more active role of the public sector in technology generation and transfer was demanded by farmers.

Proper sulfur management in winegrapes may potentially reduce both insecticide/miticide use and the human/social problems associated with sulfur's impacts on air quality and odors, particularly in wine tourism regions. Data from California's unique Pesticide Use Report (PUR) database, which records agricultural pesticide applications on all crops throughout the state, are used to determine if either winegrape grower's choice of sulfur formulation (dust only, wettable only, or a combination) or overall sulfur use rates (pounds per acre planted) correlate with annual miticide and insecticide use in Fresno and Madera (hotter–drier) and Napa and Sonoma counties (cooler–damper). Annual sulfur use has declined by 36–55% in these counties from 1993 to 2009. In 2000, the greatest number of growers in each county were combination users; wettable users were higher in Napa (38%) and Sonoma (34%) than in Fresno (24%) and Madera (10%); and dust-only users varied little (15–19%) across the four counties. Data for 2005 and 2009 showed similar trends. The use of high-toxicity insecticides in Fresno was 387% higher than in Napa–Sonoma in 2000, but was 25 and 8% lower in 2005 and 2009, respectively. In Fresno, wettable sulfur users used less high-toxicity insecticides; while in Fresno and Madera dust users used less lower-risk insecticides than combination or wettable sulfur users. No significant differences in insecticide use were evident between the three sulfur use categories in Napa–Sonoma (P = 0.97). On average, dust users in Fresno–Madera used more high-toxicity miticides than combination or wettable sulfur users in 2000. That trend decreased in the data for 2005 and 2009. Average miticide use in Fresno–Madera was higher than in Napa–Sonoma by 1349% in 2000, 1103% in 2005 and 146% in 2009. Higher sulfur use intensities among individual growers in Fresno–Madera were positively correlated with greater use of high-toxicity miticides in 2000 and 2005, but not 2009. The comparable results for Napa–Sonoma were less clear. Since PUR data represent statewide information on pesticide use decisions in real-world farming scenarios, it can complement data from field and laboratory studies. Expanding these analyses to compare pesticide use by individual growers across years, or to correlate pesticide usage with any published mite field surveys may shed more light on the enigmatic relationship between sulfur fungicide use and mite outbreaks in winegrapes.

This study is aimed to evaluate the efficiency of biochar and crude glycerin as additives in N retention throughout the composting of cattle slaughterhouse waste in static piles receiving forced aeration. There were five treatments (control, biochar accounting for 5 and 10%, and glycerin accounting for 5 and 10%, both at total solids) and four times (20, 50, 70 and 90 days of composting). The slaughterhouse waste was composted with a bulking agent at a ratio of 3:1, and the mixtures of waste and the tested additives were placed in nylon bags. The piles reached thermophilic temperatures soon after the process started and following turnings. The reductions of volatile solids, carbon, hemicellulose, cellulose and lignin were not influenced by the additives, resulting in averages of 69.1, 67.1, 62.1, 51.6 and 35.3%, respectively. The control showed greater N losses (58.38%), compared to the treatments with additives. The inclusions of biochar yielded an average loss of 48.47% N, while 10% of glycerin resulted in the lowest N losses (44.83%). The use of biochar and glycerin as additives in the composting of slaughterhouse waste is recommended in order to decrease N losses and improve the concentration of nutrients, without compromising the biodegradation of organic components.

Due to correlations between purchasing patterns and diet disparities, differences in food shopping patterns and strategies across income levels and other socio-economic characteristics is a widely-studied research area. Most extant literature uses either primary or secondary data, which are often characterized by, respectively, limited geographical scope and considerable level of detail, or wide geographical reach but low detail. That literature also reveals contrasting results based on methods, data sources and geographic location. In this paper, we use three different datasets to characterize the differences in purchasing patterns across income levels, rural–urban status and other variables of food shoppers in the Northeastern USA and compare these trends with existing research. While many of the findings corroborate previous studies, new findings include less reliance on superstores overall, except for rural respondents, and a greater reliance on limited assortment supermarkets for SNAP and low-income households. Food purchasing differences are described by race and ethnicity, income and education, and children in the household. The analysis presented here includes a portion of the work performed by an interdisciplinary team of researchers engaged in the USDA National Institute of Food and Agriculture's Agriculture and Food Research Initiative project Enhancing Food Security in the Northeast (EFSNE). By using primary data from shoppers' intercept surveys, and secondary data from two large datasets, one of household food purchases and the other of food expenditures, we identify purchasing decisions holding at both the case-study (limited geography) and broader geographic (entire Northeast) levels, which both support previous findings and reveal the need for additional research in this area.

Decision making in organic farming is related to risk and uncertainty, and options must be evaluated in the decision-making process. This paper presents the methodology of an integrated deterministic simulation system (KARSIM 1.0) application for decision-making support on organic farms in northeastern Slovenia. An emphasis to modify the net present value (NPVt) criterion by incorporating the real options approach was made. Its application is shown in organic spelt (Triticum aestivum ssp. spelta McKey) production and processing using two real options approaches, the Black–Scholes and binomial models. The NPVt indicates that the decision to process spelt for animal fodder is financially unfeasible, while the real options approach differentiates the results by organic spelt grain and flour production for human nutrition. It may be concluded that the real options approach can be useful when assessing projects with uncertainty, sunk costs and irreversibility, and it can provide for examining agricultural investment decisions.

Renewable Agriculture and Food Systems is a multi-disciplinary journal which focuses on the science that underpins economically environmentally and socially sustainable approaches to agriculture and food production. The journal publishes original research and review articles on the economic, ecological and environmental impacts of agriculture; the effective use of renewable resources and biodiversity in agro-ecosystems; and the technological and sociological implications of sustainable food systems. It also contains an open discussion Forum, which presents lively discussions on new and provocative topics. However, the opinions of the Forum and responses are solely those of the authors and do not necessarily reflect the opinions of Renewable Agriculture and Food Systems or Cambridge University Press.

With the extensive focus on lean conformation in the finished hog over the past 25 years, there is some indication that pork quality has suffered and taste has been bred out of today's pork. Similar to the Certified Angus Beef program (a breed noted for intramuscular fat), small-scale farmers can promote a different ‘upscale’ pork by using breeds that will focus on pork taste exclusively, and feeding diets (possibly apart from corn and soybeans) to enhance flavor. Two experiments were devised to examine the influence of breed, rearing environment and diet on fresh pork quality and flavor. In Trial 1, three sow breed groups (Tamworth, Tamworth×Landrace, or Hampshire×Landrace) were mated to Duroc boars. Littermates (91 pigs total) were assigned randomly at weaning to one of three treatments: (1) confinement, (2) dry-lot and (3) pasture. All pigs were full fed a 16% crude protein (CP) grow-finish ration. Pasture pigs were allowed access to plots consisting of predominately white and crimson clovers with warm-season grasses (Bermuda grass and crab grass). Hampshire crosses had higher Minolta L* scores, indicating a paler, less desirable loin. Pork quality was similar across rearing environments except for lower initial pH levels observed in the pasture system and higher drip-loss percentage recorded in both outdoor systems. In Trial 2, 42 Tamworth×Duroc littermates were randomly assigned to one of two rearing environments (confinement or pasture) at 55 kg and full fed a 14% CP diet. Pigs finishing on pasture had access to standing, mature barley. Pork from the pasture system was darker than that from pigs reared in confinement. No differences were observed in sensory evaluation of the pork for the rearing environments examined. For both trials, intramuscular fat levels (<2%) and visual color scores were too low to be considered for ‘upscale’ markets. Alternative diets to produce niche-market pork are unlikely to influence flavor without adequate levels of marbling.

Manufactured biobased mulch (biomulch) films and fabrics are useful non-chemical weed management tools, but are not typically used for high-density plantings of vegetables such as lettuce (Lactuca sativa L.) and carrot (Daucus carota L. subsp. sativus). However, it may be possible for crop roots to grow through a permeable biomulch membrane. Our objective was to demonstrate the potential for lettuce and carrot to germinate on and grow through biomulch, and assess changes in crop growth and yield. Biomulches included a 100% polylactic acid (PLA) biofabric and a PLA (37%) + soybean meal (63%) biofabric (PLA + SOY). Seeds were placed directly on biomulch and top-dressed with a soil mix or compost. Crop roots grew through the biomulch (despite visible constriction in carrot), and total yields were either the same or greater than those in the no-mulch control. PLA + SOY increased lettuce yield by 72% and also degraded faster than the PLA mulch. Results hold promise for improving weed control and reducing labor in high-density vegetable plantings.

Reducing adverse environmental consequences of modern industrial agriculture requires an ecological transition of agricultural practices. An important determinant of adoption of new agricultural practices by producers is the perceived profitability of these practices. The profitability of ecological agricultural practices tends to rely on improved crop prices and reduced input use. Transition to such practices often entails increased profit volatility (risk) and long-term returns (temporal profile). Ideal candidates for transition would therefore be aware of the output price and input costs dimensions of their profitability, as well as willing to assume some risks and show patience to value long-term returns. We assessed the potential for such a transition along these three dimensions (profitability, risk aversion and time preferences) in a group of soybean producers in the agricultural frontier of the Brazilian Amazon. Primary data were collected using a questionnaire and economic tests in the region of Santarém (State of Pará, Brazil). We found that, while these producers have a low-risk aversion that could favor the adoption of new ecological practices, their focus on increasing yields to enhance profits and their high discount rates considerably reduces their propensity to adopt these practices.

Alongside associated forms of socially and politically conscious food production, community food growing is routinely connected to a wide range of social and environmental benefits. However, robust evidence in support of these associations remains scant, and while the conversation has shifted in recent years to take account of the sometimes unintended or negative aspects of these activities, no consensus has been reached about how such forms of food growing should adapt to new conditions, or be scaled up to maximize their positive impacts. A July 2016 conference was organized to address this strategic shortfall. This themed issue presents the papers resulting from the conference.

Intermediated markets account for two-thirds of local sales and are slowly gaining more attention. These marketing channels generally include all opportunities in the local supply chain that are not direct-to-consumer transactions, including sales to grocery stores, restaurants, regional aggregators such as food hubs, as well as schools, universities, hospitals and other institutions. The marketing chains are often regionally based and are shorter than the typical conventional food supply chain. These markets, like all other marketing opportunities, have their advantages and challenges for farmers. A set of nine papers in this themed issue explores a range of aspects of intermediated market channels, with some papers taking a broad view and others examining how farmers navigate specific markets. Together, the papers point to the potential that intermediated markets offer farmers interested in marketing their products locally and regionally, as well as reveal the entrepreneurial spirit that some of these market channels embody. While growth has been substantial and some successes evident, the papers also point to the challenges facing farmers who are trying to improve the economic situation of their farms.

Organic farming seems to be a solution in environmentally sensitive zones such as the protection zone of Tahtalı Dam, which supplies fresh water to Izmir, the third largest city in Turkey. Greenhouse vegetable production is the major agricultural activity in this area (Menderes Township). However, due to the pollution risk from agriculture, governmental authorities have issued a regulation discouraging the use of chemicals within the collection basin of the dam. An on-farm project was conducted in 2001 to introduce organic greenhouse vegetable production in the Tahtalı Dam preservation area and to serve as a model for other areas in Turkey facing similar ecological problems. Two irrigation levels and four organic fertilizers were tested on the growth of cucumbers (Cucumis sativus cv. Sardes). The four fertilizers were two rates of farmyard and poultry manure (30 and 50 tons ha−1) with and without two organic fertilizers based on either bacteria or algae. During the growing period, pests and diseases were monitored weekly and preparations allowed in organic agriculture were used when necessary. Plant diseases did not create any significant problem, but the pest population, in particular spidermites, increased. No significant differences in cucumber yield were found between the fertilizer and irrigation treatments tested. However, it should be noted that yields from the addition of 30 tons ha−1 of farmyard or poultry manure and organic fertilizers were the same as those for 50 tons ha−1 of manure alone. The average total yield was 13 kg m−2, within an acceptable range for short-term crop production in this region, but 55% lower than a conventional substrate culture trial nearby. However, due to reduced production costs and a price premium for organic products, the organic produce yielded a net return of US$1.12–1.79 per m2 whereas that for conventional bag culture produce was US$0.55 per m2. Our results indicate that, under present conditions, organic greenhouse cucumber production has less environmental impact and is more economic than conventional bag culture, due to reduced chemical input and reduced operating and initial investment costs.

This study examined the response of forage crops to composted dairy waste (compost) applied at low rates and investigated effects on soil health. The evenness of spreading compost by commercial machinery was also assessed. An experiment was established on a commercial dairy farm with target rates of compost up to 5 t ha−1 applied to a field containing millet [Echinochloa esculenta (A. Braun) H. Scholz] and Pasja leafy turnip (Brassica hybrid). A pot experiment was also conducted to monitor the response of a legume forage crop (vetch; Vicia sativa L.) on three soils with equivalent rates of compost up to 20 t ha−1 with and without ‘additive blends’ comprising gypsum, lime or other soil treatments. Few significant increases in forage biomass were observed with the application of low rates of compost in either the field or pot experiment. In the field experiment, compost had little impact on crop herbage mineral composition, soil chemical attributes or soil fungal and bacterial biomass. However, small but significant increases were observed in gravimetric water content resulting in up to 22.4 mm of additional plant available water calculated in the surface 0.45 m of soil, 2 years after compost was applied in the field at 6 t ha−1 dried (7.2 t ha−1 undried), compared with the nil control. In the pot experiment, where the soil was homogenized and compost incorporated into the soil prior to sowing, there were significant differences in mineral composition in herbage and in soil. A response in biomass yield to compost was only observed on the sandier and lower fertility soil type, and yields only exceeded that of the conventional fertilizer treatment where rates equivalent to 20 t ha−1 were applied. With few yield responses observed, the justification for applying low rates of compost to forage crops and pastures seems uncertain. Our collective experience from the field and the glasshouse suggests that farmers might increase the response to compost by: (i) increasing compost application rates; (ii) applying it prior to sowing a crop; (iii) incorporating the compost into the soil; (iv) applying only to responsive soil types; (v) growing only responsive crops; and (vi) reducing weed burdens in crops following application. Commercial machinery incorporating a centrifugal twin disc mechanism was shown to deliver double the quantity of compost in the area immediately behind the spreader compared with the edges of the spreading swathe. Spatial variability in the delivery of compost could be reduced but not eliminated by increased overlapping, but this might represent a potential 20% increase in spreading costs.

The Canary Islands are a Spanish archipelago, where the greatest water demand comes from agriculture. Being an outermost European region that receives a large number of tourists per year, the need for greater food sovereignty becomes more important. It is vital to undertake studies on the water footprint (WF) of the main crops, in order to identify the irrigation practices of local farmers and establish recommendations for water saving through improvement of these practices. The results of this study show that the average WF for bananas in the Canary Islands is 340.80 m3 t−1 ± 34.07 and for avocadoes is 1741.94 m3 t−1 ± 286.16. The WF models proposed can explain 92 and 86% of the total variance of the WF for banana and avocado crops, respectively. The WF of both crops can be reduced, and this work can be a starting point for improvement. Farmers will face a change in temperature and water availability due to climate change; useful water saving strategies for local farmers can now be made based on estimation of the WF with yield and net needs data.

In agricultural regions, like Whatcom County, Washington, crop and dairy production co-exist, but increased agricultural specialization and intensification have divorced what was, historically, an integrated approach to production. This agricultural segregation contributes to farm, regional and watershed-scale nutrient imbalances, and several different management approaches have been devised to improve, correct and close these nutrient cycling disparities. In high-density production regions, utilizing locally produced bio-based fertilizers may provide one avenue toward closing regional nutrient loops. Technologies such as dairy-operated nutrient recovery systems may help improve the flow of nutrients between dairy and cropping systems by extracting nutrients from raw manure and producing materials that are more easily used on farms than raw manure. To evaluate the potential impact of a nutrient recovery system and its related product, we estimated nitrogen balances between cropland use and manure production within Whatcom County, Washington and examined a theoretical scenario in which a specific nutrient recovery product was utilized across the region. We considered one economic barrier, transportation cost, and calculated a hypothetical comparison for transporting nitrogen in two forms, a downstream nutrient recovery product and raw manure. The scenarios presented here demonstrate a potential gap between regional nutrient supply and demand, illustrate the tradeoffs with a technological approach, and make clear that both technological tools and practical management strategies are needed to address the challenges of redistributing nutrients in high-density production areas.

Across the Midwest, substantial funding and personnel time have been allocated to encourage farmers to adopt a wide range of conservation practices but adoption rates for many of these practices remain low. Prior research focuses largely on the influence of individual-level factors (e.g., beliefs, attitudes) on conservation practice adoption rather than on contextual factors (e.g., seasons) that might also play a role. In the present study, we considered seasonal variation and its potential influence on farmer cover crop decision-making. We first established how farmer temporal and financial resources fluctuate across the year and then compared the annual agricultural decision and cover crop decision calendars. We also considered farmer cover crop perceptions and likely behaviors. To study this, we surveyed the same Midwestern farmers in the spring, summer and winter within a 12-month period. Results indicated that farmers were generally the least busy and the most financially comfortable in the winter months. Moreover, farmers perceived the benefits of cover crops differently throughout the year. These results indicate that seasonality can be a confounding factor which should be considered when designing and conducting research and farmer engagement. As researchers, it is our responsibility to understand the specific calendar experienced by our sample and how that may influence responses so we can examine theory-supported factors of interest rather than seasonality as a driver of farmer responses. As practitioners, it is important to use research findings to engage with farmers about conservation in a way that prioritizes communicating about the most salient aspects of the practice at the time of year when farmers will be most receptive.

Although research has demonstrated the positive nutritional value and environmental benefits associated with edible insect consumption, several factors challenge the growth and development of the edible insect industry for human consumption in the US and Canada. Cultural and psychological factors account for much of the aversion US and Canadian consumers display. The absence of specific regulation also constitutes a structural barrier to more widespread production and sale of edible insects. Compared to the US, the European Union has a more developed edible insect industry and has enacted legislation that removes some of the barriers. As consumer awareness of the putative health benefits of edible insects increases, more comprehensive regulations may emerge to keep pace with the growth of this industry. Overall, a multi-disciplinary approach that addresses both benefits and barriers to consumption is needed to facilitate a robust market for edible insects in the US and Canada.

Systems advocating alternative agriculture would appear to be handicapped by the amount and the minutiae of human labor required. Is this really a threat to the continuity of farms associated with these systems? We do not believe that this directly hampers the survival of a farm. We advance the theory that continuity is not just down to chance; the farmer at the time chooses to prolong the life of the farm and more especially to look for a successor. We have shown through a study conducted in central France (Auvergne) that the main guarantee of organizational sustainability, that which sustains the business as a viable entity when another person takes over, is when a farmer thinks of his farm as an entity-cum-project supporting a meaningful life plan. A farmer might also see his farm solely as capital or as heritage, but neither of these last two attitudes is sufficient for him to ensure the spirit of his enterprise is passed on. There is a particularly large number of farmers in the first category (entity-cum-project) who adopt alternative farming practices, which are meaningful. It also seems to be the case that the manner of working is closely linked to the moral principles of farmers who use alternative systems. Moreover, the same objective amount of work that might be thought excessive in a system that puts strong emphasis on high productivity, is regarded as normal in an alternative system. Farmers often approach extension advisors to help reorganize their working conditions. We maintain that alternative systems have peculiarities with regard to work that make this type of advice difficult. Our aim is to help advisors clearly construct the input they give to the various types of farmers. We put forward a typology of possible practices as regards advice on work, according to assessments farmers have made about the amount of work they do and their way of working. The large number of hours devoted to an alternative farming activity and the nature of that activity, whether demanding or linked to practices thought archaic, are not always a handicap to the continuity of an alternative system. On the contrary, these features can be its hallmark.