Agroecological Infrastructures Research Articles

How the Green Architecture of the 2023–2027 Common Agricultural Policy could have been greener

A new 5-year Common Agricultural Policy has been in place since January 2023. Like its predecessors, this new policy will fail to deliver significant climatic and environmental benefits. We show how the Green Architecture of the policy relying on the three instruments of conditionality, eco-schemes, and agri-environment and climate measures could have been used more consistently and effectively. Our proposals are based on core principles of public economics and fiscal federalism as well as on research results in agronomy and ecology. Conditionality criteria are the minimal requirements that every agricultural producer must meet. Farmers should be rewarded for efforts that go beyond these basic requirements through eco-schemes for global public goods complemented by agri-environment and climate measures centred on local public goods. Eco-schemes should cover the whole agricultural area by targeting permanent grasslands, crop diversification, and green cover and non-productive agro-ecological infrastructures. We discuss trade-offs that our proposals could generate.

Wild plants in hedgerows and weeds in crop fields are important floral resources for wild flower-visiting insects, independently of the presence of intercrops

The availability of diverse floral resources is crucial for the maintenance of pollinating insects and the pollination service they provide in agricultural landscapes. Ensuring plant diversity is thus essential for the maintenance and even restoration of pollinator communities. Many studies have highlighted the beneficial effects for pollinating insects of the floral resources provided either by uncultivated plants in agroecological infrastructures such as hedgerows and in crop fields, or by the addition of cultivated flowers through intercropping. However, the role of these different co-occurring vegetation types in providing floral resources to wild flower-visiting insects remains unexplored simultaneously, especially regarding their potential interacting effects. Using a paired design sampling approach, we investigated the contribution of floral resources provided by hedgerows, weeds in crop fields, and legumes intercropped with winter cereals, and their interacting effects, to the abundance of different groups of wild flower-visiting insects, plant-insect interactions and insect preferences. Our results show that the abundance of most groups of floral visitors were enhanced by the cover or species richness of floral resources provided by hedgerows or by weeds in crop fields. Interactions between uncultivated plants and insects were driven by the presence of some particular ‘preferred’ plant species offering either abundant, accessible or high-quality floral resources. By contrast, abundance of floral visitors was not enhanced by the addition of legume flowers through intercropping. The positive effects of flowering wild plants in hedgerows and crop fields remained mostly unchanged in the presence of intercrops, because of the limited contribution of legumes in providing attractive floral resources to floral visitors. Our results highlight the critical role of floral resources provided by weeds in crop fields for diverse flower-visiting insects, in addition to the floral resources provided by hedgerows. We recommend that agri-environment schemes should promote a wide diversity of floral resources at field margins through the retention of existing semi-natural elements or the sowing of wildflower mixtures. More importantly, our study encourages the seeking of alternative forms of weed management, which support a trade-off between the maintenance of pollinating insects and pollination service provision on the one hand, and crop yields and incomes for farmers on the other.

Individual flowering phenology shapes plant–pollinator interactions across ecological scales affecting plant reproduction

The balance of pollination competition and facilitation among co-flowering plants and abiotic resource availability can modify plant species and individual reproduction. Floral resource succession and spatial heterogeneity modulate plant-pollinator interactions across ecological scales (individual plant, local assemblage, and interaction network of agroecological infrastructure across the farm). Intraspecific variation in flowering phenology can modulate the precise level of spatio-temporal heterogeneity in floral resources, pollen donor density, and pollinator interactions that a plant individual is exposed to, thereby affecting reproduction. We tested how abiotic resources and multi-scale plant-pollinator interactions affected individual plant seed set modulated by intraspecific variation in flowering phenology and spatio-temporal floral heterogeneity arising from agroecological infrastructure. We transplanted two focal insect-pollinated plant species (Cyanus segetum and Centaurea jacea, n=288) into agroecological infrastructure (10 sown wildflower and six legume-grass strips) across a farm-scale experiment (125 ha). We applied an individual-based phenologically explicit approach to match precisely the flowering period of plant individuals to the concomitant level of spatio-temporal heterogeneity in plant-pollinator interactions, potential pollen donors, floral resources, and abiotic conditions (temperature, water, and nitrogen). Individual plant attractiveness, assemblage floral density, and conspecific pollen donor density (C. jacea) improved seed set. Network linkage density increased focal species seed set and modified the effect of local assemblage richness and abundance on C. segetum. Mutual dependence on pollinators in networks increased C. segetum seed set, while C. jacea seed set was greatest where both specialization on pollinators and mutual dependence was high. Abiotic conditions were of little or no importance to seed set. Intra- and interspecific plant-pollinator interactions respond to spatio-temporal heterogeneity arising from agroecological management affecting wild plant species reproduction. The interplay of pollinator interactions within and between ecological scales affecting seed set implies a co-occurrence of pollinator-mediated facilitative and competitive interactions among plant species and individuals.

Population Dynamics of Arthropods in New Caledonian Citrus Orchards

Aims: Agroecological infrastructures are central to the preservation of arthropod populations and ecosystem services associated. There is little data on the population dynamics of New Caledonian citrus orchards. Thus, this study focuses on the response of arthropods to four management methods in the orchard: conventional management, inter-row vegetated, row mulching and edge windbreaks.
 Place and Duration of Study: This study was conducted in the village of La Foa in New Caledonia. It took place over three months, from the end of February to the end of May 2022.
 Methodology: To collect the greatest possible diversity of insects, four complementary trapping methods were used: pitfall traps, yellow plates, Malaise traps and sweeping nets. Once collected, the trapped insects are then sorted and identified. The sorting is done with a binocular magnifying glass. Insects are identified using specific determination keys, documentation, or with the help of the Reference Collection of Terrestrial Invertebrates of New Caledonia - Xavier Montrouzier (CXMNC). When identification is not immediately possible, a morphotype number is assigned. For each species and morphospecies, a photograph is taken. Alpha and beta diversity was studied using rarefactions, Shannon index and Generalized Linear Models.
 Results: A positive effect of agroecological infrastructures on insects’ abundance and diversity was recorded. In contrast, low arthropod abundances and diversities were presented in the orchard under conventional management (P < 0.001). Mulching management was the parameter showing the much higher insects’ abundance. Moreover, populations dynamics were generally correlated with the related infrastructures. Thus, windbreaks acted as ecological corridors and the inter-row vegetation as refuge habitats for beneficial insects. 
 Conclusion: These results demonstrate the damage of conventional agriculture on arthropod diversity in New Caledonian orchards. They also show that agroecological infrastructures can bring back insect biodiversity, especially with the mulching management.

In‐field cover crop strips support carabid communities and shape the ecological trait repartition in maize fields

Abstract The 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.

Ecopolitana: A Plan of Cities, Territory, Landscape, and Ecology

A national green planning strategy has recently been introduced in the Italian urban planning sector, aimed at making all local initiatives undertaken nationwide consistent with each other. At a regional level, Friuli Venezia-Giulia has recently implemented a Landscaping Plan, which is of an urban planning and ecological nature at an intermediate level between national and local. This article describes the local green plan of Latisana, which has been titled Ecopolitana, given that it represents the experimental phase, at a regional level, of the possibilities offered by landscape planning and design. Specifically, it outlines the multi-disciplinary approach used, demonstrating how landscape planning can be compared to the sustainable development of cities, with specific regard to the agricultural sector. In this regard, a low-intensity cropping model is also suggested, based on the principles of agroecology and landscape ecology, which has already been implemented in the historical rural landscape of Plasencis (UD) and investigated through GIS analysis and remote sensing processes. Its aim is to be the starting point for the achievement of the goals set in the 2030 Agenda, especially Goals 13 (climate action) and 15 (life on land), given the current scarcity of agroecological infrastructures in the area of Latisana (UD) and the high percentage of soil used for intensive cropping.

Promoting generalist predators of crop pests in alley cropping agroforestry fields: Farming system matters

Developing agroecological practices that enhance biological control of crop pests is a major issue for the transition of agriculture towards sustainable and biodiversity-friendly systems. Agroecological infrastructures (AEI) are devoted to the support of ecosystem service providers, although they have mixed effects on natural enemies of crop pests. In temperate regions, alley cropping agroforestry involves within-field AEI, in the form of tree rows and associated understory vegetation strips. The objective of this study was to assess the potential of generalist predators (carabid beetles and cursorial spiders) to control weed seeds and invertebrate pests in alley cropping vs pure crop systems, under two contrasting farming systems (conventional vs organic). Predator surveys were carried out in May and June 2017 in South-Western France over 12 winter cereal fields. Our study revealed that the effect of alley cropping was modulated by the farming system. Under conventional farming, alley cropping had a negative effect on the activity-density and species richness of generalist predators, especially regarding carnivorous carabids whose activity-density was reduced by nearly 50%. Under organic farming, alley cropping enhanced both the activity-density and complementarity of generalist predators, with a two-fold increase in the activity-density of seed-feeding carabids (predominantly granivorous and omnivorous), potentially promoting weed seed and invertebrate pest control. Our results suggest that the effectiveness of AEI in promoting natural enemies depends on the farming system at the field scale, which affects resource availability and determines spillover intensity between habitats. AEI are often perceived as sources of natural enemies. However, sink and retention effects (i.e. reduced or delayed spillover into crop fields due to higher attractiveness of AEI) should not be overlooked as they can explain the mixed impacts of AEI on natural enemy communities.

Public goods in rural areas as endogenous drivers of income: Developing a framework for country landscape valuation

Rural areas are where many environmental and cultural public goods occur, creating a country landscape. Their agro-ecological infrastructure delivers things people directly value, such as food, fibre and energy, but the market fails when it comes to the valuation of public goods. For this purpose, indirect valuation methods are used, but these encounter many methodological problems. The aim of this study is to create a conceptual framework for the economic rent valuation (ERV) method, which estimates the economic rent resulting from the random endogenous influences of public goods on production factors in rural areas. The ERV method attempts to reduce the biases of the market-based and contingent valuation methods that result from the model misspecification and unrevealed preferences, and advocates for adoption of the variance component model. The article also presents an illustrative application of ERV based on the case of the West Pomeranian region of Poland, which reveals the potential advantages of ERV.

Development of sustainable plant protection programs through multi-actor Co-innovation: An 8-year case study in Swedish apple production

This article assesses the multi-actor co-innovation research that was carried out between 2010 and 2018 by researchers and apple production actors. The aim was to develop sustainable integrated pest management methods that, with the help of an agroecological whole system approach, would be both desirable and feasible to implement in practice. Whilst a novel pest management strategy based on semiochemicals arrived at and was rapidly adopted by growers, the enhancement of biological control through functional diversity required long-term learning. This is explained by substantial differences in the perception of the economic risk and the necessary knowledge behind the adoption of each method. The knowledge gap due to the reduced number of extension advisors and the conflict between the cost incurred when implementing low-impact pest control methods and reduced profitability of apple crops were pointed out as major contradictions by the actors. We suggest that strengthened regional agroecological infrastructure support along with the expansion of public advisory service personnel would reduce the farmer economic risk and share the responsibility for a safer environment and healthier food. Similarly, relevant authorities should be provided with resources to allow for safety assessments of candidate low-risk plant protection products at the regional scale. As a conclusion, we recognised that in our region sustainable agroecosystem management through feasible and desirable plant protection strategies could not be developed solely by focussing on the efficiency of the tools because the cost-effectiveness and thus the implementation of such tools depended greatly on the simultaneous co-innovation of the socio-technical system. Local stakeholders need to harmonise their vision and standpoints to engender long term socially and environmentally sound objectives providing a base to promote, finance and extensively adopt innovative plant protection strategies within the Skåne region.

Remote Sensing and Cropping Practices: A Review

For agronomic, environmental, and economic reasons, the need for spatialized information about agricultural practices is expected to rapidly increase. In this context, we reviewed the literature on remote sensing for mapping cropping practices. The reviewed studies were grouped into three categories of practices: crop succession (crop rotation and fallowing), cropping pattern (single tree crop planting pattern, sequential cropping, and intercropping/agroforestry), and cropping techniques (irrigation, soil tillage, harvest and post-harvest practices, crop varieties, and agro-ecological infrastructures). We observed that the majority of the studies were exploratory investigations, tested on a local scale with a high dependence on ground data, and used only one type of remote sensing sensor. Furthermore, to be correctly implemented, most of the methods relied heavily on local knowledge on the management practices, the environment, and the biological material. These limitations point to future research directions, such as the use of land stratification, multi-sensor data combination, and expert knowledge-driven methods. Finally, the new spatial technologies, and particularly the Sentinel constellation, are expected to improve the monitoring of cropping practices in the challenging context of food security and better management of agro-environmental issues.

Enhancing planned and associated biodiversity in French farming systems

AbstractIn a context of global change involving uncertainty in agricultural production, agroecological systems need to reduce their dependency on inputs and increase their resilience. Biodiversity-based techniques are promising, as they provide production services based on biological processes. Tracking farmer practices is an original approach aiming at identifying and analysing alternative systems and supporting the development of these techniques. We studied, for the first time, the on-farm implementation of six biodiversity-based techniques: (i) agroecological infrastructures, (ii) cropped varietal mixtures, (iii) agroforestry, (iv) intercropping, (v) cover cropping and (vi) crop rotation diversification. We first analysed the combinations of these techniques in a large sample of 194 French farmers. A multiple correspondence analysis followed by a hierarchical cluster analysis on principal components resulted in groups of farms with different combinations of these techniques. Then, deeper interviews were conducted with 29 farmers across three regions to analyse the various methods of applying the techniques in the context of their farm and to identify the conditions for their successful implementation. Taking advantage of this large and rare sample of almost 200 interviewed farmers, we identified six different groups of farms. From farms applying mainly cover cropping to comply with European regulations to much diversified farms implying the redesign of the farming system, we support the idea that different strategies of implementation of such biodiversity-based techniques co-exist. The in-depth interviews demonstrated that the level of diversification is related to farm characteristics and four factors mainly favoured the development of such techniques on farms: (1) available labour force and (2) specialised machinery (internal factors) as well as (3) access to market opportunities and (4) the exchange of knowledge through networking (external factors). Surprisingly, the conservation agriculture farmers of our sample did not apply significantly more biodiversity-based techniques. However, our results indicated that organic farmers applied significantly more of these techniques. Our results suggest that enhancing knowledge exchange through networks would favour the broader application of such techniques. It could also be relevant to gather farmers, industries and public authorities to favour the emergence of market opportunities.

Bayesian inferences of arthropod movements between hedgerows and orchards

Hedgerows are agro-ecological infrastructures that are assumed to enhance biodiversity in an agro-ecosystem and the control of crop pests. However, local movements of arthropod predators from hedgerows to crops remain poorly understood. In this research, these movements were analysed in eleven commercial apple orchards over two weeks in the spring of 2014. Predators were indirectly marked by spraying ovalbumin on the hedgerows. Canopy and ground predators were captured using beating and pitfall traps, respectively, in both the orchards and the hedgerows, and individuals marked by ovalbumin were detected using ELISAs. Approximately 20% of the 1272 captured predators were identified as marked. Movements between the orchards and the hedgerows of the most abundant predator taxa (Forficula auricularia, Chrysoperla sp., Philodromus spp., Cheiracanthium mildei, and Nebria brevicollis) and of four guilds (ground spiders, ground beetles, canopy spiders and canopy insects) captured across the eleven locations were estimated using a Bayesian model. On one hand, canopy insects and ground spiders were less likely to stay in the hedgerows than were the canopy spiders and ground beetles. On the other hand, the canopy spiders and ground beetles were less likely to stay in the orchard than were the canopy insects and ground spiders. However, there were exceptions within these groups: F. auricularia and N. brevicollis exhibited a high probability of staying in the hedgerow and in the orchard, respectively. Overall, these results demonstrate the frequent movements that occurred between the orchard and the adjacent hedgerow in a diverse range of predator taxa. The probabilities of movement were further affected by the characteristics of the orchard for most taxa. Therefore, agro-environmental measures that focus on hedgerow management require consideration of the local arthropod predator communities and their characteristics to enhance pest control in apple orchards.

Agroecological infrastructures to enhance the presence of natural enemies against aphids

Agroecological infrastructures to enhance the presence of natural enemies against aphids

Impact of Agroecological Infrastructures on the Dynamics of Dysaphis plantaginea (Hemiptera: Aphididae) and Its Natural Enemies in Apple Orchards in Northwestern France.

Apple orchard production is facing new environmental and societal challenges, resulting, in particular, in strong pressure to reduce pesticide use. Cider-apple production, for which the perfect visual aspect of fruits is not a marketability imperative, offers good opportunities to study production systems that are developing new agronomic strategies, which could be subsequently extended to all apple-production types. Agroecological infrastructures play an important role in providing shelter, food resources, or reproduction habitats to many arthropods. Consequently, setting-up agroecological infrastructures in the vicinity of or within orchards could increase natural enemy presence and thus improve the biological control of pests. In this study, we focused on Dysaphis plantaginea (Passerini), one of the major pests in apple orchards in Europe, which causes important economic production losses. During two years (2014 and 2015), we monitored the population dynamics of D. plantaginea, its natural enemies, and mutualistic ants in commercial production cider-apple orchards. The influences of the cider-apple cultivar, insecticide use, and distance to agroecological infrastructures (hedgerows and flower strips) were assessed. Our results suggest that flower strips favor an increase in natural enemy abundance in the vicinity of the orchards and could thus play an important role in the production system by improving the biological control of D. plantaginea.

Studies on Biodiversity Diagnosis of Vineyard Farms at the Agro-Ecological Infrastructure Level

In Romania, the vine farms are currently spread on approximately 180.000 ha, therefore an important part of biodiversity, functional or planned is present. To avoid a biodiversity decline it is necessary for the vineyards to have a clear evidence of the state of their biodiversity.Based on the results obtained from the studied vineyards, during 2015, the agro-ecological infrastructure or AEI percent based on the actual area occupied varies between 7% and 35%. Evaluation of the implementation AEI during 2015 in wine-growing farms in Romania showed that the amount of semi-natural elements is not sufficient to stop the loss of biodiversity and their quality needs to be favored also.

Farming systems and insect predators

Predatory carabids, staphylinids and spiders were monitored from 1981 to 1987 in a Dutch project concerning the development of arable farming systems. During this period epigeic predators in the conventional, integrated and organic systems were sampled using pitfall traps. The effects of crop type and farming system on species diversity, abundance and guild structure was analysed using trap data from wheat, pea, sugar beet, potato, onion and carrot fields. Predator abundance and species composition were found to be clearly affected by the farming system. However, in most cases the type of crop appeared to be of greater importance. Crops with a greater cover early in the season, like winter wheat and peas appeared to be more favourable than late and open crops like onions or carrots. Both system and crop effects were more apparent in carabids than in spiders or staphylinids. Only minor effects of farm management were found on species richness. Again, the crop itself seemed to be the main structuring factor. It is concluded that the presence and quality of predator populations is mainly determined by crop structure and crop-related factors. The role of favourable crops and field size in predator enhancement is discussed in relation to the agroecological infrastructure of the landscape.