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Agroecology territories : places for sustainable agricultural and food systems and biodiversity conservation
No full textInternational audienceThe development of sustainable agricultural and food systems is of significant importance considering the still-growing world population. For this, it is imperative to consider not only quantitative production issues, but also environmental issues such as water pollution, biodiversity loss, and land degradation as well as social and economic issues such as organization of supply chains and communication and coordination among stakeholders. However, the development of sustainable agricultural and food systems is so far almost exclusively proposed either at the scale of specific agricultural systems or for selected supply chains. Still strongly neglected is the development of sustainable systems at a territorial scale. We, therefore, present here the concept of agroecology territories. We define agroecology territories as places where a transition process toward sustainable agriculture and food systems is engaged. Three major domains must to be considered for the transition to take place: adaptation of agricultural practices; conservation of biodiversity and natural resources; and development of embedded food systems. Stakeholder group strategies, developed by those who actively engage in these three domains and are themselves actors in the transition, are integral to agroecology territories
A participative network of organic and conventional crop farms in the Seine Basin (France) for evaluating nitrate leaching and yield performance
No full textInternational audienceIn the Seine Basin, characterized by intensive arable crops, most surface and groundwater is contaminated by nitrate (NO3-). A collaborative study was set up, involving a network of volunteer farmers, to investigate NO3- leaching with ceramic cups (90 cm deep) on whole crop rotations of organic (OF) and conventional (CF) commercial farms in the Seine Basin. A total of eight CF and six OF systems were studied (63 fields) in five different soil and climate conditions, taking into account a wide diversity of practices (including low or no exogenous N inputs, systematic catch-crop implementation, and no tillage) and use of different exogenous organic matter (EOM) such as biogas residue; slurry; poultry manure; and cow and horse manure. Over the 2 years, OF cropping systems (including alfalfa) led to a lower average sub-root concentration (37 +/- 9 mg NO3- l(-1)) than CF systems (48 +/- 19 mg NO3- l(-1), +/- standard deviation between farms). The water inflows calculated ranged from 86 to 190 mm depending on the year for the 4-month drainage period. The amounts of N leached were on average 23%lower in OF (12.5 +/- 2.9 kg N ha(-1) yr(-1)) than in CF systems (16.2 +/- 6.3 kg N ha(-1)yr(-1)). Concerning farming practices, the main impacting factors were the use of EOM in fall, the lack of catch crops before spring, and the proportion of legumes in the rotation. Overall, this wide collaborative network highlights good and innovative practices by CF and OF farmers attempting to decrease NO3- in groundwater
Evaluer la robustesse des vaches laitières: l’approche biologique
No full textEvaluer la robustesse des vaches laitières: l’approche biologique. Séminaire Ensembl
Assessing the diversity of trade-offs between life functions in early lactation dairy cows
No full textThis study objective was to develop a method to characterize the diversity of trade-offs between life functions expressed by dairy cows. Trade-offs between life functions involve adaptive responses of dairy cows to suboptimal nutritional environments. Until now, they have been explored mainly by examining unfavorable correlations between two traits. These two-trait approaches are limiting for exploring the diversity of trade-offs among cows. A multi-trait and dynamic method was developed to phenotype trade-offs between life functions involved in cow fitness (lactation, reproduction, and ability to survive) and explore their diversity. Records from 334 lactating cows reared in two experimental INRA (France) units were used to study the dynamics of cow milk yield, body condition changes and reproduction performance. The analysis focused on the first 13 weeks postpartum, when cows are supposed to experience a negative energy balance. Ten variables accounting for the dynamics of responses were calculated and included in a clustering analysis. Four main clusters of trade-offs were obtained. Profile 1 of trade-off (N=53) included cows giving priority to lactation and mobilizing much of their body fat reserves, with poor reproductive performance. Trade-off profile 2 (N=111) identified cows mobilizing much of their body fat reserves, giving priority to reproduction at the expense of high milk yield. Trade-off profile 3 (N=67) consisted of thin cows presenting difficulties in all functions: a large body-reserve mobilization after calving that does not benefit to milk yield and long delays before reproducing and low success rates. Profile 4 of trade-off (N=103) was composed of cows with no trade-off between functions, since they recorded average milk yield, maintained their body condition and had good reproductive performances. Our approach highlighted the relevance of considering the three life functions simultaneously when phenotyping dairy cows for their ability to manage prioritization between life functions and this multi-trait clustering approach represents an operational tool to do so, using readily available farm data. Since classification of cows into clusters is not fully determined by the breed or parity, our study underlined also the utility of better understanding the mechanisms that drive nutrient allocation between life functions. We also believe in the benefit of considering this individual diversity, as a herd management tool for farmers
Agriculture biologique et développement local
No full textInternational audienceL’agriculture biologique (AB) est de plus en plus envisagée comme une réponse à des enjeux collectifs, environnementaux, économiques et sociaux. Dans cet article, nous montrerons comment dans l’histoire du développement de l’AB, les questions du territoire et des dynamiques locales prennent de plus en plus d’importance. Ensuite, en nous appuyant sur l’analyse approfondie de six initiatives territoriales, nous analyserons la diversité et la complexité de ces dynamiques locales, tant du point de vue desobjectifs de ces projets que de celui des acteurs impliqués, de leurs formes de gouvernance et de leurs trajectoires. Enfin, la discussion sera consacrée, dans une perspective opérationnelle, aux difficultés, aux facteurs de réussite comme aux compétences professionnelles nécessaires pour les animateurs en charge de l’accompagnement de tels projets
Rural agricultural regions and sustainable development: a case study of the Allgäu region in Germany
No full textInternational audienceSince the United Nations Conference on Environment and Development in 1992 in Rio de Janeiro, sustainable development became an important issue. Sustainable development often focuses on a single sector or parameter such as tourism, energy supply, water management, different aspects of nature conservation, or economy. In this paper, we provide a comprehensive picture of the development of a region since the Middle Ages and discuss whether this development can be evaluated as socially, economically and ecologically sustainable. We carried out a combined qualitative–quantitative assessment where we use quantitative data and indicators when available, as well as literature sources and expert knowledge from the region for a qualitative assessment. We judge that generally a sustainable development in the Allgäu region can be found, although also some critical points and contentious issues exist. An overall good economic and income situation for most people, the good ecological conditions and rich biodiversity, the relatively well-established social structure, as well as the identity of the people with the region and comparatively low social discrepancy, can be positively stated. In contrast, different actual and future threats exist such as new or planned infrastructure, increasing traffic or tourism activities in certain areas that degrade habitats and reduce species richness, intensification of agriculture in certain areas, but also abandonment of agriculture in other areas, loss of traditions and customs, and declining numbers of smallholders. The objective for the region would be to minimise these negative impacts and reinforce positive trends to assure the sustainable development of the Allgäu
Le Département comme référence pour des formes d'organisation collective territorialisées
No full textDirect and correlated responses to selection in two lines of rabbits selected for feed efficiency under ad libitum and restricted feeding: I. Production traits and gut microbiota characteristics
No full textInternational audienceTo get insights into selection criteria for feed efficiency, 2 rabbit lines have been created: the ConsoResidual line was selected for residual feed intake (RFI) with ad libitum feeding and the ADGrestrict line was selected for ADG under restricted feeding (–20% of voluntary intake). The first objective of this study was to evaluate, after 9 generations of selection, the direct and correlated responses to selection on production traits in the 2 lines for traits recorded during growth. Second, applying the 2 feeding conditions used for selection to both selected lines plus the control unselected line (generation 0, G0) in a 2 × 3 factorial trial, the line performances were compared and the gut microbiota of the lines was characterized. The correlated responses in feed conversion ratio (FCR) were remarkably equivalent in both selected lines (–2.74 genetic σ2a) but correlated responses in other traits were notably different. In the ConsoResidual line, selection for decreased RFI resulted in a small negative correlated response in BW at 63 d old (BW63) and in a null response in ADG. In the ADGrestrict line, on the contrary, the correlated response in BW63 was substantial (+1.59 σ2a). The 2 selected lines had a FCR reduced by 0.2 point compared with the G0 line, and the same difference was found in both feeding regimens (P < 0.001). Indeed, selection on ADG would lead to heavier animals with no significant reduction of feed costs, whereas selection on RFI leads to lower feed costs and no increase of animal BW under ad libitum feeding. Altogether, our results do not suggest any genotype × environment interaction in the response to feeding regimens. The intestinal microbial communities from efficient rabbits differed from their unselected counterparts in terms of fermentation end products and microbial phylotypes, suggesting a central role of these microbes in the better feed efficiency of the rabbits
Utilisation de données de réseaux de mesures du niveau d'eau et de l'humidité du sol pour l'évaluation du modèle hydrologique distribué PUMMA: application au bassin du Mercier, France
No full text[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAUInternational audienceContext: Use of distributed hydrological models in a hypothesis testing framework (Clark et al., 2011) Evaluation of models using distributed data Objectives: Assessment of the value of distributed networks of surface soil moisture and water level sensors to identify problems with models parameters and representations Application to the PUMMA (Peri-Urban Model for landscape Management, Jankowfsky et al., 2014) distributed model in the Mercier catchment (6.6 km2, France)
A manifesto for the valorization of wild edible plants
No full textInternational audienceEthnopharmacological relevanceWild foods constitute an essential component of people's diets around the world, but despite their widespread use and their cultural importance, wild edible plants (WEPs) lack recognition as significant contributors to the human diet in developed countries.Materials and methodsWe stimulate national and international bodies dealing with food and agriculture, to increase their attention and investments on WEPs, leveraging the results of scientific investigation, enhancing the link between in situ conservation strategies and sustainable use of plant genetic diversity.Results and conclusionsWEPs should be reconsidered throughout their value chain, capturing their important socio-cultural, health, and economic benefits to indigenous and local communities and family farmers who are engaged in their production and wild-harvesting