Agriculture must face a number of very pressing environmental issues. We used the prototyping method to design three innovative cropping systems, each satisfying three ambitious goals simultaneously: (1) overcoming a major environmental constraint, which represents a major break regarding objectives to be reached in current cropping systems (differing between systems: a ban on all pesticides but with chemical nitrogen (N) fertilizer permitted; reducing fossil energy consumption by 50%; or decreasing greenhouse gas (GHG) emissions by 50%), (2) meeting a wide range of environmental criteria and (3) maximizing yields, given the major constraint and environmental targets. A fourth cropping system was designed, in which the environmental and yield targets were achieved with no major constraint (the productive high environmental performance cropping system (PHEP) system). The performances of these innovative cropping systems were compared to a conventional system in the Ile-de-France region. We used a three-step prototyping method: (1) new cropping systems were designed on the basis of scientific and expert knowledge, (2) these system prototypes were assessed with tools and a model (ex ante assessment) adjusted to the set of constraints and targets, with optimization by an iterative process until the criteria were satisfied and (3) evaluation in a long-term field experiment (ex post assessment), which is currently underway. We describe only the first two steps here, together with the results of the prototypes assessment with tools and a model. The pesticide, energy and GHG constraints were fulfilled. All these innovative systems satisfied environmental criteria in terms of nitrogen and phosphorus management, pesticide use, energy consumption and crop diversity. For the pesticide-free system, the soil organic matter indicator was lower than expected due to frequent plowing (every 2 years) and yields were 20–50% lower than for the PHEP system, depending on the crop considered. We focus our discussions on the design methodology and the availability of scientific knowledge and tools for projects of this type.

There is a need to design intensive cropping systems that can reap multiple benefits from annual forages including animal feed, soil fertility and weed control. Considering pea/oat (Pisum sativum cv. 40–10/Avena sativa cv. Legget) as a standard green manure, this study investigated the productivity, weed competitiveness, utilization and nitrogen (N) benefit from grazed and ungrazed green manures to spring wheat (Triticum aestivum cv. Waskada) and fall rye (Secale cereale cv. Hazlet). A set of 3-year experiments was carried out in Carman, Manitoba, Canada in 2009, and was repeated in 2010 and 2011. Green manures were grazed by 2–3 ewes and 2–5 lambs for 24 h (1111–1667 sheep days per ha). Averaged over experiments pea/oat mix, hairy vetch (Vicia villosa L.) and sweetclover (Melilotus officinalis cv. Norgold) above-ground dry matter (DM) production were 5036, 5032 and 4064 kg ha−1, respectively. Lentil (Lens culinaris cv. Indianhead), a mixture of seven species and soybean (Glycine max cv. Prudence) produced the least amount of DM over 3 years; 3589, 3551, 3174 kg ha−1, respectively. Pea/oat and hairy vetch were the most weed-competitive species and, averaged over 3 years, contained less than 15% weed DM. Utilization of green manures by grazing animals varied little among species across years and ranged from 28 to 86% for individual species and years. When combined across experiments grazing increased N availability to the wheat crop. The grazing effect was significant for wheat DM production, N uptake and grain N, but not significant for yield across experiments. Averaged over 3 years, wheat took up 107 kg N ha−1 from grazed plots versus 98 kg N ha−1 from ungrazed plots. A significant species×management interaction for total (wheat+fall rye) N uptake in 2009 indicated that increasing the proportion of legumes in the green manure increased N benefit from grazing. Fall rye productivity was not affected by grazing. We recommend pea/oat and hairy vetch as two green manure species to enhance the overall system performance to achieve high level of DM production, good weed competition, utilization by sheep and provision of N benefit to the following wheat and fall rye crops.

Changes in methanogenic archaea were investigated in pilot-scale experiments during one- and two-stage mesophilic anaerobic digestion (AD) of food waste. Methane yields were 379.7±75.3 liters of methane per kg of volatile solids [L-CH4 (kg-VS)−1] added to the system, during one-stage operation, and 446±922 L-CH4 (kg-VS)−1 added during two-stage operation. Populations of methanogenic archaea were monitored quantitatively by targeting the functional gene for methyl-coenzyme-M reductase (mcrA) using real-time quantitative polymerase chain reaction techniques. During one-stage operation, mean mcrA gene concentrations were 2.48×109±2.7×109 copies ml−1. Two-stage operation yielded mean mcrA gene concentrations of 9.85×108±8.2×108 copies ml−1 in the fermentation and 1.76×1010±8.5×109 copies ml−1 in the methanogenesis reactors, respectively. Diversity of archaea in the methanogenic reactors was investigated by denaturing gradient gel electrophoresis targeting the V3 region of 16S rRNA of archaea. The Shannon index (H) was 2.98 for one-stage operation and 7.29 for two-stage operation, suggesting greater archaeal diversity in the two-stage AD. The fivefold increase in methanogenic archaea populations during the two-stage operation, as indicated by mcrA gene concentration, corresponded to an increase in methane production rates. While the diversity may also be related to the stability of the microbial bioprocesses and improved methane production rates, the correlation between diversity and production rates should be studied further.

Rotational grazing (RG) is a livestock management practice that rotates grazing cattle on a scale of hours to days among small pastures termed paddocks. It may beneficially affect stream channels, relative to other livestock management practices. Such effects and other beneficial effects on hydrology are important to RG's potential to provide a highly multifunctional mode of livestock farming. Previous comparisons of effects of RG and confinement dairy (CD) on adjoining streams have been restricted in scale and scope. We examined 11 stream-channel characteristics on a representative sample of 37 small dairy farms that used either RG or CD production methods. Our objectives were: (1) to compare channel characteristics on RG and CD farms, as these production methods are implemented in practice, in New York, Pennsylvania and Wisconsin, USA; and (2) to examine land use on these farms that may affect stream-channel characteristics. To help interpret channel characteristic findings, we examined on-farm land use in riparian areas 50 m in width along both sides of stream reaches and whole-farm land use. In all states, stream-channel characteristics on RG and CD farms did not differ. Whole-farm land use differed significantly between farm types; CD farms allocated more land to annual row crops, whereas RG farms allocated more land to pasture and grassland. However, land cover in 50 m riparian areas was not different between farm types within states; in particular, many RG and CD farms had continuously grazed pastures in riparian areas, typically occupied by juvenile and non-lactating cows, which may have contributed sediment and nutrients to streams. This similarity in riparian management practices may explain the observed similarity of farm types with respect to stream-channel characteristics. To realize the potential benefits of RG on streams, best management practices that affect stream-channel characteristics, such as protection of riparian areas, may improve aggregate effects of RG on stream quality and also enhance other environment, economic and social benefits of RG.

Farmers are innovators and experimenters and not just adopters of introduced technologies. The innovations developed by farmers could complement the highly promoted externally driven technologies in addressing the numerous challenges facing agriculture. The aim of this paper was to identify outstanding innovations developed by smallholder farmers in northern Ghana, and prioritize the high potential ones for further scientific validation or dissemination. Using an innovation contest that rewards farmers' creativity, we identified 29 promising innovations. Additionally, 19 innovations were scouted through a household survey. The innovations are largely extensive modifications of existing practices or combinations of different known practices in unique ways to save costs or to address crop and livestock production constraints. While some of the identified innovations can be recommended or disseminated to other farmers, most of them may require further validation or research. However, validating all of these innovations will be very expensive and time-consuming. We propose the multi-criteria decision-making analysis (MCDM) as a simple method to prioritize farmers' innovations. Using this method, we find that among the most promising innovations are those involving the control of weeds, pests and diseases using plant residues and extracts, and the treatment of livestock diseases using ethnoveterinary medicines. We briefly explain the six most highly ranked innovations. This case study from northern Ghana provides further proof that smallholder farmers develop diverse and spectacular innovations to address the myriad challenges they face, and these need to be recognized and promoted. We also conclude that contest and MCDM are useful methods that can be applied in unearthing and prioritizing farmer innovations, respectively.

The environmental benefits of cover cropping are widely recognized but there is a general consensus that adoption levels are still quite low among US farmers. A survey was developed and distributed to more than 200 farmers engaged in two sustainable farming organizations in NC and the surrounding region to determine their level of utilization, current practices and perceptions related to cover cropping. The majority of farms surveyed had diverse crop production, production areas <8 ha, and total gross farm incomes <US$50,000. Approximately one-third of the survey population had an organic production component. Eighty-nine percent of participants had a crop rotation plan and 79% of the total survey population utilized cover cropping. More than 25 different cool- and warm-season cover crops were reported. The statements that generated the strongest agreement about cover crop benefits were that cover crops: increase soil organic matter, decrease soil erosion, increase soil moisture, contribute nitrogen to subsequent cash crops, suppress weeds, provide beneficial insect habitat and break hard pans with their roots. Economic costs associated with cover cropping were not viewed as an obstacle to implementation. A factor analysis was conducted to identify underlying themes from a series of positive and negative statements about cover crops. Pre- and post-management challenges were able to explain the most variability (30%) among participant responses. Overall, participants indicated that the incorporation of residues was their greatest challenge and that a lack of equipment, especially for no-till systems, influenced their decisions about cover cropping. Farmers did not always appear to implement practices that would maximize potential benefits from cover crops.

Localization is one process/outcome that is proffered as key to the ‘grand challenges’ that currently face the food system. Consumers are attributed much agency in this potential transformation, being encouraged from all levels of society to exert their consumer muscle by buying local food. However, due to the social construction of scale it cannot be said that ‘local food’ is a definite entity and consumers understand the term ‘local food’ differently depending on their geographic and social context. As such, the research upon which this paper is based aimed to provide a nuanced understanding of how consumers in the particular spatial and social contexts of urban and rural Ireland understood the concept of ‘local food’. A specific objective was to test the theory that these consumers may have fallen into the ‘local trap’ by unquestioningly associating food from a spatially proximate place with positive characteristics. A three-phase mixed methodology was undertaken with a sample of consumers dwelling in urban and rural areas in both Dublin and Galway, Ireland: 1000 householders were surveyed; 6 focus group discussions took place; and 28 semi-structured interviews were carried out. The results presented in this paper indicate that for most participants in this study, spatial proximity is the main parameter against which the ‘localness’ of food is measured. Also, it was found that participants held multiple meanings of local food and there was a degree of fluidity in their understandings of the term. The results from the case study regions highlight how participants’ understandings of local food changed depending on the food in question and its availability. However, the paper also indicates that as consumers move from one place to another, the meaning of local food becomes highly elastic. The meaning is stretched or contracted according to the perceived availability of food, greater or lesser connections to the local producer community and the relative geographic size of participants’ locations. Our analysis of findings from all three phases of this research revealed a difference in understandings of local food among participants resident in urban and rural areas: participants dwelling in rural areas were more likely than those in urban areas to define local food according to narrower spatial limits. The paper concludes with an overview of the practical and theoretical significance of these results in addressing the current dearth of research exploring the meaning of local food for consumers and suggests avenues for future research.