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Fostering the Implementation of Nature Conservation Measures in Agricultural Landscapes: The NatApp
No full textInternational audienceLarge-scale, high-input, and intensified agriculture poses threats to sustainable agroecosystems and their inherent biodiversity. The EU Common Agricultural Policy (CAP) covers a great number of nature conservation programs (Agri-Environment and Climate Measures, AECM) aiming to encourage sustainable agriculture. Currently, farmers are not encouraged to broadly implement these measures due to the lack of structured information, overly complicated and unclear application procedures, and a high risk of sanctions. In addition, the current structures are associated with time-consuming monitoring and control procedures for the paying agencies. Digital technologies can offer valuable assistance to circumvent relevant barriers and limitations and support a broader uptake of AECM. NatApp is a digital tool that supports and guides farmers through the complete process of choosing, applying, implementing, and documenting AECM on their fields in accordance with legal requirements in Germany. We introduce the concept of NatApp and analyze how it can simplify and encourage the uptake and implementation of AECM. This study identifies its unique features for the provision of information and documentation opportunities compared with other digital farming tools focused on sustainable agriculture and outline how it can support farmers to actively contribute to more sustainable agriculture
In‐field cover crop strips support carabid communities and shape the ecological trait repartition in maize fields
No full textInternational audienceThe enhancement of pest regulation service in crops depends for a large part on the capacity of agroecological practices to increase the presence of key species or functional traits in arthropod communities within fields.We investigated the effects of undestroyed strips of winter cover crops in maize fields on carabid community composition, and on the distribution of three ecological traits: diet, wing status and body size.We found that the community composition and the distribution of ecological traits in the in-field cover crop strips had commonalities with both adjacent cropped areas and field margins. Some species were recorded mostly or only in the strips indicating that strips could support carabid species and help increase local diversity from the first year of establishment.The activity-density of Poecilus cupreus and Pterostichus melanarius was higher in the cropped proximity of the strip, and the body size was influenced by the distance from the strip.Our results suggest that carabid communities are shaped by the habitat type, but the influence of such agroecological infrastructures on communities of adjacent crops is minor beyond a distance of 10 m. However, overall species abundance was increased and thus potentially provided enhanced pest regulation
Undestroyed winter cover crop strips support wild bee abundance and diversity in intensive cropping systems
No full textInternational audienceAgricultural intensification is known to be one of the main drivers of pollinator decline, in particular because flower resources are often scarce in intensively cultivated landscapes. Agroecological practices such as wildflower strips implementation are seen as effective to mitigate this food scarcity by increasing the abundance, diversity and temporal continuity of the flower resources. However, in intensive cropping systems, these practices are often poorly adopted by farmers because of technical and economic barriers. We designed a practice based on the conservation of winter cover crop strips in the middle of spring crops and assessed the value of such undestroyed cover crop strips for the enhancement of pollinator populations, and the conservation of wild bee species. Cover crop strips on farmers’ fields were surveyed and compared to existing herbaceous field margins. Our results showed that within-field cover crop strips are effective in increasing the availability and continuity of flower resources for pollinators. We recorded a higher abundance, richness, taxonomic and functional diversity of bees in the covered crop strips than in the field margins, but no significant effect on hoverflies. Wild bees were supported by the sown flowers of the strips during spring, before the main blooming period of the spontaneous flowers of the field margins, and the combination of sown species of three different botanical families in the strips supported wild bees with different ecological traits, including oligolectic bees. Our findings indicate that this practice can support complementary flower resources, but also highlight the importance of protecting and extending spontaneous plant patches such as field margins for the conservation of rare and specialist bees
Microencapsulation of Antimicrobial trans-Cinnamaldehyde: Effect of Emulsifier Type, pH, and Drying Technique
No full textInternational audienceTwo plant-based emulsifiers, soybean lecithin and pea protein isolate, were studied for their emulsifying and encapsulating capacities of an antimicrobial molecule, trans-cinnamaldehyde (TC), at two different pH values, three and seven, and after drying with two different techniques, spray-drying and freeze-drying. To characterize the obtained capsules, various physicochemical tests were conducted to examine particle size, encapsulation efficiency, thermal and moisture stability, and powder morphology. The spray-dried (SD) and freeze-dried (FD) powders had an average particle size of 8.35 µm and 144.49 µm, respectively. The SD powders showed similar encapsulation efficiency (EE) for soybean lecithin and pea protein isolate with an average value of 95.69%. On the other hand, the FD powders had lower EE compared to SD powders, with an average of 58.01% for lecithin-containing powders and 83.93% for pea-protein-containing powders. However, the water content of FD powders (2.83%) was lower than that of SD powders (4.72%). The powders prepared at pH 3 showed better thermal stability. Morphological analysis showed spherical particles for SD powders and irregular shapes for FD powders. Nanoemulsions as well as dried powders showed interesting antimicrobial activities against Escherichia coli and Listeria innocua, confirming their potential use as natural preservatives in foods
Agronomic assessment of two populations of intermediate wheatgrass—Kernza® ( Thinopyrum intermedium ) in temperate South America
No full textInternational audienceBackground: Kernza® intermediate wheatgrass is a perennial grain and forage crop that can provide several ecosystem services. Major research efforts focused on Kernza have taken place in high latitudes. The goal of this studywas to evaluate, for the first time, the agronomic performance of Kernza in a low‐latitude region with mild winters.Methods: A KS‐cycle 4 Kernza population (A) was planted in spring in Wisconsin, USA, and selected in one cycle for lower vernalization requirements, obtaining a new population (B). These two populations, at three nitrogen (N) fertilization rates, were evaluated in a full factorial, completely randomized field experiment in Uruguay over 2 years. Results: The populations were similar in grain yields and flowering time in the 1st year, but population B had 63% lower grain yield in the 2nd year and20% lower forage yield throughout the experiment. Increasing the N rate to 160 kg ha−1 led to a 63% increase in grain yield and 28% increase in forage yield across populations. Forage yields and nutritive values were similar tothose reported in the northern hemisphere. However, grain yields for both the 1st (316 kg ha−1) and 2nd year (41 kg ha−1) were lower due to reduced flowering and weed competition. Conclusions: Expansion of Kernza to lower‐latitude regions will require further breeding to improve reproductive performance
From practice-based evidence to evidence-based practice: how to close the loop?
No full textInternational audienceAgroecology not only requires changes in practice but also for the redesign of agricultural extension and innovation pathways. Farmer’s experience and innovative farming groups are placed at the foreground to produce inspiring evidence. Identifying or developing innovative practices experienced by farmers, capitalizing on this experience, and promoting the deployment of these innovations by relying on farmer groups is a strategy currently being implemented in France to develop agroecology. For extension and advisory services, basing advice to farmers on situated evidence entail challenging tasks in examining and evaluating evidence. In this paper, we examine how EAS implement this new approach through an analysis of the changes in the professional activities, postures, and skills of advisors/facilitators. To address these questions, a generative experiment started officially in October 2022 in a dialogical way between a pragmatic inquiry and NG’s professional activity. An action-research project was designed based on what was asked to NG by its employer, i.e. to capitalize practice-based evidence to support evidence-based practices. We argue that capitalizing on-farm innovations is a new encompassing narrative leading to professional uncertainty. It seems to be a way for advisors/facilitators and their institutions to be accountable. Finally, the implementationof horizontal learning challenges advisors/facilitators professionalism through the need to better combine technical expertise with facilitation skills
Les sols des microfermes urbaines au sein de l’économie circulaire : utilisation de produits résiduaires organiques et stocks de carbone des sols
No full textNational audienceLes micro-fermes urbaines connaissent aujourd'hui un développement croissant porté par des mouvements associatifs et un soutien politique territorial. En milieu urbain, les micro-fermes sont des exploitations de petite taille (moins de 1,5ETP par ha), associent souvent des bénévoles à leur modèle économique et génèrent une diversité d'activités. Les différentes fonctions attendues d'elles (approvisionnement alimentaire, activité pédagogique, sociale et culturelle, rétention d'eau, valorisation des déchets, paysage…) sont directement liées à la diversité des services écosystémiques qu'elles peuvent rendre. En particulier, les micro-fermes urbaines pourraient jouer un rôle important dans l'économie circulaire urbaine, car une pratique courante consiste à utiliser les déchets organiques de la ville pour amender voire construire les sols, qui peuvent être situés en pleine terre ou sur les toits. Nous avons évalué les services écosystémiques rendus par sept micro-fermes urbaines situées en région parisienne et nous sommes ici concentrés sur l'utilisation des déchets urbains et les stocks de carbone, à partir d’enquêtes et de mesures. Nous avons constaté que des sources très diverses de déchets organiques étaient utilisées, souvent avec la création de circuits locaux. Les stocks de carbone organique des sols étaient de 15 à 40,6 kgC.m-2 pour les sols en toiture et/ou construits et entre 8 et 15 kgC.m-2 pour les sites au niveau du sol, sur une profondeur de 0-30 cm. Ces valeurs très élevées, bien que développées sur de petites surfaces, montrent que la mise en place de micro-fermes urbaines contribue des services écosystémiques régulateurs en ville, au sein d'une économie circulaire
Earthworm populations and diversity under annual and perennial wheat in a North to South gradient in Western Europe
No full textInternational audienceThe challenge to sustain food security while halting the loss of biodiversity and soil quality might be achieved by a transformation in agriculture from high-input management of annual crops to a more nature-based solution introducing perennial cropping systems. This study analysed earthworm communities (numbers, biomass, ecological categories) and diversity over two years, from annual wheat and perennial intermediate wheatgrass (IWG, Thinopyrum intermedium, Kernza®) within the EU-Biodiversa project NAPERDIV from Southern to Northern Europe. Study sites in France, Belgium and Sweden represented diverse soil, climatic and plant growth conditions. In total, 16 species were identified with IWG in France having the highest (13) and annual wheat in Belgium and Sweden the lowest (7) species numbers. Improved biodiversity under perennial wheat was indicated by alpha-diversity indices (Simpson index, Shannon-Weaver index, Evenness). Earthworm abundance and biomass were generally significantly higher in IWG across the three sites (GLMM model). The overall mean earthworm number under IWG was 424.7 No. m−2 compared to 164.7 No. m−2 for annual wheat. Mean earthworm biomass under IWG was 83.7 g m−2 relative to 45.9 g m−2 under annual wheat, respectively. Remarkably, mean number of juvenile earthworms was several times higher on IWG sites relative to the annual comparatives. Moreover, endogeic and epigeic earthworms were supported on the IWG plots. Beta diversity (Sorensen coefficient) emphasised highest similarity between Belgium and Sweden and lowest between France and Sweden, indicating a possible South to North distribution within Western Europe. The Canonical Correspondence Analysis showed discrete clusters for study sites and species distribution (including the subtypes of Allolobophora chlorotica) in relation to soil parameters (pH, soil texture, TOC, TN, WHC, C–N ratio). The CCA additionally discriminated between annual and perennial plots in France. In summary, earthworm communities were more diverse under IWG and seemed to follow a South to North gradient
Conservation tillage influences soil structure, earthworm communities and wheat root traits in a long-term organic cropping experiment
No full textWe thank M. Claude Barber, a French organic farmer, who allowed us to use a field and participated in this study over 16 years.International audienceBackground and Aims: Organic farmers are showing increasing interest in using conservation tillage to improve the biological activities of soils. Here, we assessed whether conservation tillage in organic farming improves earthworm populations, root growth and soil physical quality in a sandy loam after 16 years of experiment. Methods: We compared the effect of a tillage gradient, with of two non-ploughed treatments (superficial tillage [ST] at 15 cm; very superficial tillage [VST] at 5–7 cm) and two ploughed treatments (moldboard ploughing [MP] at 30 cm; shallow moldboard ploughing [SMP] at 20 cm). Soil clod types, penetration resistance, abundance and activity of earthworms, root traits and biomass were assessed. Results: VST decreased soil compaction in topsoil (0 to 10 cm) compared to ploughed treatments (MP and SMP), but led to more compacted soil at 15 to 30 cm. Earthworm biomass (especially anecic) was higher under VST compared to MP and SMP and their galleries were better connected to the soil surface. However, there was no significant difference in the total volume of pores or diameter of galleries between 0 and 30 cm. Soil compaction in the non-ploughed treatments affected root traits, especially under VST, with lower specific root length, higher root diameter, and lower root tip elongation compared to MP and SMP. Conclusion: Biological activity did not compensate for the compaction of a sandy soil after 16 years without ploughing in organic farming. A more integrated approach (i.e. considering all 5 soil health principles) is needed to sustain soil health and functions, and meet current expectations about “ecological intensification”