Organic cropping systems that utilize winter grown cereal–legume cover crop mixtures can increase plant available nitrogen (N) to a subsequent cash crop, but the rate of N release is uncertain due to variations in residue composition and environmental conditions. A study was conducted to evaluate N availability from rye (Secale cereale L.)–hairy vetch (Vicia villosa Roth) cover crop mixtures and to measure the response of organically grown sweet corn (Zea mays L.) to N provided by cover crop mixtures. Nitrogen availability from pure rye, pure hairy vetch, and rye–vetch mixtures was estimated using laboratory incubation with controlled temperature and soil moisture. Sweet corn N response was determined in a 2-year field experiment in western Washington with three cover crop treatments as main plots (50:50 rye–vetch seed mixture planted mid September, planted early October, and none) and four feather meal N rates as subplots (0, 56, 112 and 168 kg available N ha−1). Pure hairy vetch and a 75% rye–25% hairy vetch biomass mixture (R75V25) released similar amounts of N over 70 days in the laboratory incubation. But, the initial release of N from the (R75V25) treatment was nearly 70% lower, which may result in N release that is better timed with crop uptake. Cover crops in the field were dominated by rye and contained 34–76 kg ha−1 total N with C:N ranging from 18 to 27. Although time of planting and management of cover crop quality improved N uptake in sweet corn, cover crops provided only supplemental plant available N in this system.

Over the past decade, organic food sales and farmland have grown rapidly worldwide. As the US market for organic food has expanded, anecdotal evidence indicates that imports of organic food have increased. US organic handlers may be importing to meet consumer demand for out-of-season products, as well as products not grown domestically. Handlers may also be importing organic products that are in short supply or to reduce input costs. This paper provides the first examination of imports of organic products into the USA. Data from a national survey of certified organic handlers in 2007 are used to examine the extent, types and origins of imported organic commodities. A Heckman model is employed to investigate the factors that influence an organic handler's decision to import organic products, and the level at which organic handlers import a product. Summary results show that while many of the products being imported into the USA are those that cannot be produced domestically, such as coffee and tropical fruits, some oft-imported commodities are those that can be produced in the USA, such as soybeans, wheat, barley and berries. The summary results also show that organic handlers are procuring almost a half of their imported products from a few countries, including Canada, China, Mexico, Brazil and Indonesia. In the econometric analysis, we found those handlers prioritizing local suppliers negatively affected the facility's decision to import products. The use of a social label, such as Fair Trade, positively affected a handler's decision to import. The size of organic sales was important to both the decision to import and the share imported, with larger firms more likely to import and smaller firms less likely to import. However, once a smaller firm had decided to import, they imported a larger share. Finally, our analysis found that experiencing limited supplies or prioritizing price with suppliers did not influence a handler's decision to import products. Based on the findings, we suggest future research avenues, including studies that address consumer preferences and the impact of increased imports on domestic organic farms.

Stocker performance and production from mixed cool- and warm-season perennial pastures are important determinants of agricultural sustainability that can be influenced by management. We evaluated the factorial combination of three sources of nutrient application (inorganic only, organic+inorganic combination, and organic only) and two forage utilization regimes [low grazing pressure (LGP) and high grazing pressure (HGP)] on steer stocking density and rate, performance and production during 7 years of pasture management {tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] overseeded into existing Coastal bermudagrass [Cynodon dactylon (L.) Pers.] sod} on a Typic Kanhapludult in Georgia, USA. Nutrient source had few major impacts on responses, except for lower animal performance with organic fertilization (broiler litter) than with organic+inorganic and inorganic only fertilization, especially with LGP. Seasonal changes in stocking weight and rate occurred, not only as expected due to environmental conditions and dominant forage species present, but that also counteracted expected differences imposed by grazing pressure; signaling negative feedback of HGP on forage productivity. Steer performance was greatest in spring and summer under both grazing pressures, but was significantly reduced with increasing grazing pressure in the autumn and winter due to low forage availability. Across years, steer gainha−1 (863kgha−1) was not different between grazing pressures, but gainha−1 declined with time under HGP and was stable with time under LGP. Reducing grazing pressure to a moderate level can lead to equivalent steer production as HGP, and would likely contribute to a more sustainable balance among production, socio-economic and environmental goals. These multi-year results will help cattle producers in warm, moist climates design and implement more sustainable grazing systems.

Japan's rice terrace landscapes are not only used for food production but also appreciated as a place of high biocultural value. This paper pursues the question as to how far esthetic and spiritual values influence the motivation to participate in collective agricultural actions aiming at the conservation of traditional land use systems, the respective cultural (= traditional rural) landscapes and their biocultural diversity. Our results show that in the Ownership System of Ōyamasenmaida (Chiba Prefecture, Japan) landscape beauty is the main motivator for the mainly urban volunteers (the ‘tenants’) to participate in activities of the local Preservation Association, as well as for visitors who merely come to enjoy the scenery of the rice terraces. The active tenants, however, differ from the ‘passive’ visitors in their ecological interest and emotional attachment to the area. Interestingly, there is also a difference regarding the belief in nature spirits. A higher percentage of people who can imagine that such spirits are always present have been found among the tenants than among the visitors. Even more significant in this respect was the difference between female tenants and female visitors. To what extent spirituality is the cause for or an effect of involvement in nature conservation activities cannot be concluded from this survey. Future studies should therefore take a closer look at the connection between spirituality/religiosity and engagement in nature conservation activities. In Western countries (mainly in Central Europe or North America), nature conservation works on a more ‘scientific’ level, mobilizing engagement through scientific evidence on, for example, losses of species or biodiversity. Addressing the motivations of the volunteers on an emotional, esthetic or social level could be a promising way forward.

Agri-environmental schemes involving organic farming or set-aside management aim at promoting biodiversity and restoring ecosystem functioning in agrarian landscapes. Application of pesticides in these crop fields is strongly regulated facilitating the spread of weeds but also allowing for the establishment of endangered herbs and a variety of animals. Recent studies found gastropods and earthworms to be legitimate dispersers of seeds of wild plants. We assumed that both groups also play a significant role in the spread and establishment of wild plants within crop fields. Therefore, we are conducting a series of experiments in three different study systems on (1) the role of earthworms and gastropods as dispersers of rare herbs and weeds in an organic rye field in Germany, (2) the seed feeding behavior of gastropods of plants sown in fallow ground in Switzerland, and (3) weed dispersal in irrigated rice fields by golden apple snails in the Philippines.

This paper uses a hypothetical choice experiment to investigate Italian consumer preferences and willingness-to-pay (WTP) for organic, conventional and genetically modified (GM)-fed beef, utilizing intrinsic, search cues (price, color and visible fat) and extrinsic, credence cues. Data are gathered from three different locations in northern, central and southern Italy using a sequential Bayesian approach. Results showed that consumers attach higher value to organic meat. WTP for GM-fed beef, which is not yet sold in Italy, is well below current conventional beef prices. Organic beef is attractive to consumers because it is associated with higher animal welfare standards and environment-related issues (food miles and biodiversity preservation). No differences are found in marginal WTP estimates by gender, age, education, being a parent or having a higher level of knowledge about organic production. Ethical/environmental issues (credence cues) appear to be more relevant in explaining variation in WTP for organic beef than ordinary product characteristics (search cues).

Innovative sources of soil fertility are of utmost importance to growers in light of rising fertilizer costs and environmental concerns. Integrating livestock and crop production is one channel by which agricultural practitioners can enhance soil fertility. For this research, soil fertility was analyzed in pastured poultry/crop agroecosystems to determine whether free-ranging birds and pasture could be used to replace or supplement non-manure-based fertilizers. Soils from adjacent cropped areas were compared to plots with a recent history of pastured poultry use on two farms, and crop plants were grown in each type of soil in a replicated greenhouse experiment. Spatial variation in soil fertility was also assessed relative to location of poultry coops. Pastured poultry plots had elevated soil total C, total N, NH4+–N, NO3−–N, Olsen P, exchangeable K, organic matter, cation exchange capacity and electrical conductivity relative to the control of typically managed organic farm soils without pastured animal inputs. These soil fertility changes conferred greater biomass and height to sunflowers and beans grown in these soils relative to control soils for most treatments. Results suggest that pastured poultry can effectively fertilize soil for certain crops but that a need exists for more research into (1) phosphorus management and (2) ensuring a spatially uniform distribution of manure.

Over the past 10 years, the organic sector has expanded continuously in Europe due to policy support and a growing market demand for organic products. In line with this development, many farmers converted to organic farming each year. Nevertheless, the total number of organic farms has not increased constantly in Europe. In several countries, the absolute number of organic farms actually decreased in some years of the past decade. Some of the deregistered farmers gave up completely; others reverted to conventional agriculture. Against this background, this article aims (i) to give an overview of the extent of reversion to conventional agriculture in Europe based on statistics, (ii) to conceptualize the decision to revert in the form of a theoretical model, (iii) to compare farmers’ reasons to revert to conventional farming based on existing studies, and (iv) to identify further research needs. The importance of reversions to conventional agriculture is difficult to determine with the existing data, especially as in most cases it is not recorded as to what happened to the farms after deregistering from organic certification. The data nevertheless show that there are large fluctuations in the organic sector with many farmers entering and exiting each year. In order to reveal the farmers’ reasons for deregistering, various qualitative as well as quantitative surveys have been carried out already. For most farmers, the decision to revert is a result of different factors. Reasons for the reversion of their farms can be classified into economic motives, difficulties regarding certification and control, problems with organic production techniques as well as the farms’ macro environment. In most cases, however, economic reasons played a main role. Suggestions for organic legislation bodies, advisory services and policy makers are derived out of the findings. A deeper understanding of the influencing aspects regarding reversions and the necessary changes in the organic sector to avoid them should be an important objective of forthcoming research.

In recent decades, there has been growing interest among farming and scientific communities toward integrated crop–range–livestock farming because of evidence of increased crop production, soil health, environmental services and resilience to increased climatic variability. This paper reviews studies on existing cropping systems and integrated crop–range–livestock systems across the USA which are relevant in the context of summarizing opportunities and challenges associated with implementing long-term crop–range–livestock systems research in the highly variable environment of the central High Plains. With precipitation ranging from 305 to 484mm and uncertain irrigation water supply, this region is especially vulnerable to changing moisture and temperature patterns. The results of our review indicate that diverse crop rotations, reduced soil disturbance and integrated crop–livestock systems could increase economic returns and agroecosystem resilience. Integrating agricultural system components to acquire unique benefits from small- to medium-sized operations, however, is a challenging task. This is because assessment and identification of suitable farming systems, selection of the most efficient integration scheme, and pinpointing the best management practices are crucial for successful integration of components. Effective integration requires development of evaluation criteria that incorporate the efficiency of approaches under consideration and their interactions. Therefore, establishing the basis for more sustainable farming systems in the central High Plains relies on both long-term agricultural systems research and evaluation of short-term dynamics of individual components.

Efficient nutrient use is critical to ensure economical crop production while minimizing the impact of excessive nutrient applications on the environment. Nitrogen (N) is a key component of agricultural production, both as an input to support crop production and as a waste product of livestock production. Increasing concern for future sustainability of agricultural production and preservation of the natural resource base has led to the development of nutrient budgets as indicators and policy instruments for nutrient management. Nutrient budgets for N have been developed by the Organization for Economic Co-operation and Development (OECD) as agri-environmental indicators to compare the evolving conditions in member states, and are also used by the US Department of Agriculture Natural Resource Conservation Service (USDA-NRCS) to develop nutrient management plans. Here, we examine the crop and animal production systems, drivers impacting management choices, and the outcome of those choices to assess the utility of gross annual N balances in tracking the progress of management decisions in minimizing the environmental impact of agricultural production systems. We use as case studies two very different agronomic production systems: Mississippi, USA and Poland. State and country level data from the US Department of Agriculture and OECD databases are used to develop data for the years 1998–2008, and gross annual N balances are computed. Examination of agricultural production practices reveals that the gross annual N balance is a useful tool in identifying differences in the magnitude and trends in N within agricultural systems over large areas. Significant differences in the magnitude of the N budget were observed between the highly diversified, small-scale agriculture common to Poland, and the large-scale, intensive agriculture of Mississippi. It is noted that use of N balance indices can be problematic if the primary intent is to reveal the impact of economic drivers, such as crop prices, or management choices, such as tillage or crop rotation. Changes in cropping systems in response to commodity prices that improve N balance can be masked by detrimental growing conditions, including edaphic, biotic and weather conditions, that are outside of the producers’ control. Moreover, use of large area-scale indices such as country or state-wide balances may mask the severity of localized nutrient imbalances that result from regionalized production systems that overwhelm the nutrient balance, such as confinement livestock production. Development of a policy to address environmental impact and establish sustainable production systems must consider the year-to-year variability of drivers impacting agricultural production, and the spatial heterogeneity of nutrient imbalance.

Meeting the needs for a growing world population calls for multifunctional land use, which can meet the multiple demands of food and fuel production, environmental and biodiversity protection, and has the capacity for adaptation or resilience to climate change. Agroforestry, a land-use system that integrates trees and shrubs with crops and/or livestock production, has been identified by the International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD) as a ‘win–win’ approach that balances the production of commodities (food, feed, fuel, fiber, etc.) with non-commodity outputs such as environmental protection and cultural and landscape amenities. Evidence is now coming to light that supports the promotion of agroforestry in temperate developed countries as a sustainable alternative to the highly industrialized agricultural model with its associated negative environmental externalities. This paper reviews this evidence within the ‘ecosystem services’ framework to evaluate agroforestry as part of a multifunctional working landscape in temperate regions. Establishing trees on agricultural land can help to mitigate many of the negative impacts of agriculture, for example by regulating soil, water and air quality, supporting biodiversity, reducing inputs by natural regulation of pests and more efficient nutrient cycling, and by modifying local and global climates. The challenge now lies in promoting the adoption of agroforestry as a mainstream land use through research, dissemination of information and policy changes.

Conservation biology and agriculture share a common landscape and a future that demands novel research and practice. Inevitably, limited resources create conflict in the absence of a shared vision forward. Therefore, given the similarities in proximate and even ultimate goals, we must envision a joint path toward renewable and resilient agroecosystems. In this commentary, I highlight the root of past conflicts and share a vision of progress forward that encompasses mutually beneficial outcomes. I include six areas of anticipatory research and inquiry at the intersection of conservation biology and agriculture to better identify shared goals and facilitate more frequent communication among disciplines.