Aude Vialatte

French National Institute for Agriculture, Food, and Environment (INRAE) | INRAE · Dynamiques et Écologie des Paysages Agriforestiers (DYNAFOR)

Agriculture and forestry cover more than 75% of Europe, and invertebrate pests are a costly challenge for these two economic sectors. Landscape management is increasingly promoted as a solution to enhance biological pest control, but little is known on its effects on adjacent crop fields and woodlands. This study aims to explore the effect of the p...

The use of pesticides and the lack of resources caused by the simplification of landscapes are often cited as the main drivers of the loss of wild bees. Landscape complexity has been shown to interact with local pesticide use in studies of the effect of these factors on the abundance and diversity of insects. But, to date, few studies have simultan...

Le présent document constitue le rapport scientifique de l’Expertise scientifique collective (ESCo) sollicitée conjointement par les ministères de l’agriculture, de l’environnement et de la recherche. L’ESCo a été conduite par la Direction de l’Expertise scientifique collective, de la prospective et des études (DEPE) d’INRAE avec le soutien financi...

Agroecosystems are facing new challenges in the context of a growing and increasingly interconnected human population, and a paradigm shift is needed to successfully address the many complex questions that these challenges will generate. The transition to providing multiple services within an agroecosystem is a starting point for heightened multifu...

Diverse landscapes consisting of mixed crops are expected to support higher biological control, while also contributing to maintain farmland biodiversity. Although bats are known as predators of many farming pests, few studies to date have investigated how their foraging activity may enhance natural pest control. Here, we tested the hypothesis that...

Crop losses from pests threaten global food security and safety. In the last six decades, pest control using chemical pesticides has resulted in important yield gains per unit area, worldwide. However, the long-term sustainability of chemical pest control has been increasingly thrown into doubt due to the negative impact on human health, biodiversi...

Agroecosystems are facing new challenges in the context of a growing and increasingly interconnected human population, and a paradigm shift is needed to successfully address the many complex questions that these challenges will generate. The transition to providing multiple services within an agroecosystem is a starting point for heightened multifu...

The evidence that most agricultural landscapes are failing to deliver on biodiversity conservation and ecosystem services provision suggests that future landscapes will need to be more explicitly designed. Although recent research has produced a number of ecological and social principles that should form the basis of agricultural landscape design p...

Understanding the effects of the huge diversity of cropping systems on local biodiversity is challenging but necessary to implement agroecological systems. Through a functional approach, the translation of cropping systems into resource and disturbance gradients is a promising way to decipher the relationship between cropping systems and biodiversi...

Crop losses from pests threaten global food security and safety. In the last six decades, pest control using chemical pesticides has resulted in important yield gains per unit area, worldwide. However, the long-term sustainability of chemical pest control has been increasingly thrown into doubt due to the negative impact on human health, biodiversi...

Conservation and organic agriculture are two alternative crop management strategies associated with environmental impact reduction, leading theoretically to more biodiversity and higher ecological functioning, underpinning better ecosystem service delivery. The combination of these two farming strategies is increasingly seen as an opportunity to mi...

The sanitary situation of sugar beet crops is currently critical in France and in Europe, due to outbreaks of green peach aphids Myzus persicae, vectors of beet yellows, while the imidacloprid-based solution (neonicotinoid) is no longer authorized. In addition to alternative management methods to insecticides use at the plot level, a potentially ef...

Farming intensity and landscape heterogeneity influence agrobiodiversity and associated ecological functions. The relative contributions of these agroecosystem components to agricultural production remain unclear because of inter-relations and weather-dependant variations. Using a structural equation modelling approach, we estimated direct and indi...

Understanding effects on the huge diversity of cropping systems on local biodiversity is challenging but necessary to implement agroecological systems. Through a functional approach, the translation of cropping systems into resource and disturbance gradients is promising to decipher the relationship between cropping systems and biodiversity but has...

Biological pest control is known to depend on landscape heterogeneity. However, such relationship shows irregular pattern and seems influenced by local farming practices and natural enemies that overwinter within crop fields. The objective of this study was to assess the contribution of emerging natural enemies in spring to biological control, and...

- Context Wild pollinators depend on floral resources available in the landscape, partly provided by mass flowering crops (MFCs), such as rapeseed or sunflower. MFCs are however often grown conventionally, implying insecticide use, with potential negative effects on pollinators. - Objectives To understand whether and to what extent these crops cou...

Given the negative environmental effects of conventional agricultural techniques, the need for biodiversity-friendly agriculture systems that rely more on ecosystem services and less on chemical inputs is becoming increasingly urgent. In this paper, we focus on crop protection strategies that are alternatives to the use of pesticides. Diversificati...

Societal demand for multifunctional agricultural landscapes keeps increasing. To promote such landscapes, it is necessary to identify which components of landscape heterogeneity support multiple ecosystem services, as well as levers of action to promote these landscape properties. The social-ecological theoretical framework for multifunctional land...

Conservation biological control (CBC) has been an active research topic for the last two decades and is now one of the key ways being explored to develop agroecological production systems. Using broad concepts and indicators, recent reviews and meta‐analyses have highlighted major inconsistencies in the responses of CBC to landscape structure, reve...

Societal demand for multifunctional agricultural landscapes keeps increasing. To promote such landscapes, it is necessary to identify which components of landscape heterogeneity support multiple ecosystem services, as well as levers of action to promote these landscape properties. The social-ecological theoretical framework for multifunctional land...

With the regulation of pesticides in European agricultural landscapes, it is important to understand how pest populations respond to climate and landscape variables in the absence of pesticides at different spatial–temporal scales. While models have described individual biological processes, few have simulated complete life cycles at such scales. W...

Loss of semi-natural habitats (SNH) in agricultural landscapes affects wild bees, often negatively. However, how bee communities respond varies and is still unclear. To date, few studies have used precise descriptors to understand these effects. Our aim was to understand the respective and complementary influences of different wooded and herbaceous...

Un nombre croissant d’études scientifiques défendent que la transition agroécologique nécessite une gouvernance concertée des services et disservices écosystémiques à l’échelle du paysage ou du territoire. L’objectif du projet de recherche-action COTERRA est d’identifier les freins et leviers à l’émergence d’une telle gouvernance, au travers d'un d...

La notion de service écosystémique peut-elle aider à repenser l'action collective et la gestion concertée des territoires? La gouvernance des services écosystémiques est souvent pensée en termes de paiements fondés sur des approches marchandes ou des interventions de l'état. Des modes de gouvernance alternatifs fondés sur l'action collective à l'éc...

Increasing landscape heterogeneity by restoring semi‐natural elements to reverse farmland biodiversity declines is not always economically feasible or acceptable to farmers due to competition for land. We hypothesized that increasing the heterogeneity of the crop mosaic itself, hereafter referred to as crop heterogeneity, can have beneficial effect...

Significance Agricultural landscape homogenization is a major ongoing threat to biodiversity and the delivery of key ecosystem services for human well-being. It is well known that increasing the amount of seminatural cover in agricultural landscapes has a positive effect on biodiversity. However, little is known about the role of the crop mosaic it...

Abstract Tree diversity is increasingly acknowledged as an important driver of insect herbivory. However, there is still a debate about the direction of associational effects that can range from associational resistance (i.e., less damage in mixed stands than in monocultures) to the opposite, associational susceptibility. Discrepancies among publis...

Context While the concept of ecosystem services (ES) is well established in the scientific and policy arenas, its operationalization faces many challenges. Indeed, ES supply, demand and flow are related to ecological and social processes at multiple space and time scales, leading to complex interactions in the provision of multiple ES. Objectives...

Complex landscapes including semi-natural habitats are expected to favour natural enemies thereby enhancing natural pest biocontrol in crops. However, when considering a large number of situations, the response of natural biocontrol to landscape properties is globally inconsistent, a possible explanation being that local agricultural practices coun...

Bats and birds are key providers of ecosystem services in forests. How climate and habitat jointly shape their communities is well studied, but whether biotic predictors from other trophic levels may improve bird and bat diversity models is less known, especially across large bioclimatic gradients. Here, we achieved multi-taxa surveys in 209 mature...

Habitat management is increasingly considered as a promising approach to favor the ecosystem service of biological control by enhancing natural enemies. However, habitat management, whether at local or landscape scale, remains very uncertain for farmers. Interactions between ecological processes and agricultural practices are indeed uncertain and s...

Ce chapitre expose les différentes approches adoptées par les écologues pour étudier et comprendre les interactions entre les caractéristiques des paysages agricoles, la biodiversité et les processus écologiques qui lui sont associés. Il présente dans un premier temps l’approche classiquement centrée sur la fragmentation et l’hétérogénéité paysagèr...

GASCON est un module d’enseignement à distance composé de 4 grains pédagogiques. Les 3 derniers grains ne sont accessibles qu’après validation des acquis pédagogiques du premier grain portant sur les bases conceptuelles et méthodologiques de la PAEC. Le second grain présente les bases des approches expérimentales permettant de produire des connaiss...

The governance of ecosystem services (ES) has been predominantly thought of in terms of market or state-based instruments. Comparatively, collective action mechanisms have rarely been considered. This paper addresses this gap by proposing a conceptual framework that brings together ES, social interdependencies, and collective action thinking. We us...

Context Agroecosystems are dynamic, with yearly changing proportions of crops. Explicit consideration of this temporal heterogeneity is required to decipher population and community patterns but remains poorly studied. Objectives We evaluated the impact on the activity-density of two dominant carabid species (Poecilus cupreus and Anchomenus dorsal...

Biodiversity and ecosystem services have become major sociological, ecological and economic issues worldwide. However, understanding the complex relationships between landscape structure, biodiversity, management, ecological functions, and ecosystem services remains a challenging research question. An important example of such complexity is the sma...

Ecosystem services has become a major sociological, ecological and economic issue worldwide. Woodlands of agricultural landscapes provide valuable services although there are often underestimated and poorly used. Identifying and mapping these services at large scale is an important step to locate the available resources and to plan future managemen...

Small forest patches, smaller than 10 ha, are very common in many European landscapes and may represent a significant amount of wood available for logging, but also a support of important parts of biodiversity and of many ecosystem services. Few is known about the status of these quantities, because of the difficulty to sample such small habitats....

Biodiversity and ecosystem services have become major sociological, ecological and economic issues worldwide. However, understanding the complex relationships between landscape structure, biodiversity, management, ecological functions, and ecosystem services remains a challenging research question. An important example of such complexity is the sma...

Ecosystem services has become a major sociological, ecological and economic issue worldwide. Woodlands of agricultural landscapes provide valuable services although there are often underestimated and poorly used. Identifying and mapping these services at large scale is an important step to locate the available resources and to plan future managemen...

Participatory modelling must often deal with the challenge of ambiguity when diverse stakeholders do not share a common understanding of the problem and measures for its solution. In this paper, we propose a framework and a methodology to elicit ambiguities among different stakeholders by using a participatory Bayesian Belief Network (BBN) modellin...

The spatially-explicit AgriculTural LandscApe Simulator (ATLAS) simulates realistic spatial-temporal crop availability at the landscape scale through crop rotations and crop phenology. Intended to be linked to organism population dynamics, the simulator is developed in a multi-agent platform. The model relies on initial GIS inputs for landscape com...

ContextThe importance of landscape complexity for biological control is well-known, but its functional roles are poorly understood. Objectives We evaluated the landscape capacity to provide floral resources for beneficial insects and its consequences for biological control in fields. Methods The gut contents of adult hoverflies sampled in 41 cereal...

Scientific findings in landscape ecology suggest that a patchy landscape with a high proportion of semi-natural elements favors insect pest biological control by conservation of natural enemies’ habitats. However, little is known about how farmers perceive landscape effect on natural enemies and pests and if they might be interested in integrating...

Forest pest damage is expected to increase with global change. Tree diversity could mitigate this impact, but unambiguous demonstration of the diversity resistance relationship is lacking in semi-natural mature forests. We used a network of 208 forest plots sampled along two orthogonal gradients of increasing tree species richness and latitudes to...

In a recent opinion article, Mitchell et al. [1] propose to reframe fragmentation's effects on ecosystem services (ESs) by explicitly considering the effect of fragmentation not only on ES supply but also on ES flow. This new conceptual framework obviously represents a valuable first step towards a more robust theory linking landscape structure wit...

The impact of invasive herbivore species may be lower in more diverse plant communities due to mechanisms of associational resistance. According to the "resource concentration hypothesis" the amount and accessibility of host plants is reduced in diverse plant communities, thus limiting the exploitation of resources by consumers. In addition, the "n...

Understanding the stability of communities is fundamental in theoretical and applied ecology. Organisms atop trophic chains are particularly sensitive to disturbance, especially when they are dependent on a specific trophic resource subject to strong fluctuations in density and quality, which is the case of parasitoids. We investigated the (1) vari...

Les arbres des paysages ruraux apportent de nombreux services, dont celui de contrôler les populations de ravageurs des cultures en favorisant leurs ennemis naturels. En leur fournissant des habitats et des ressources qui leur sont nécessaires tout au long de l’année, les milieux semi-naturels arborés (haies, arbres isolés, bosquets et bois) partic...

Ouvrage suite à la journée régionale - INRA - Chambre régionale d'agriculture - 15 Octobre 2015.

Carabid beetles (Coleoptera: Carabidae) play an important role in agriculture as natural enemies of pests. The development and application of practical techniques for managing their populations is a central challenge for sustainable agriculture and depends on detailed knowledge of the ecology of individual species. However, this information is rela...

Une voie prometteuse en agroécologie est la prise en compte de l’influence des mosaïques paysagères dans les processus de régulation des ravageurs. Ce potentiel, situé à un niveau d’organisation qui dépasse celui de l’exploitation, nécessite une coordination entre différents acteurs du territoire. En effet, particulièrement lorsqu’il s’agit de bioa...

Atteindre l’objectif affiché de réduction du niveau d’usage de produits phytosanitaires tout en maintenant les niveaux de production des cultures implique la mise en place de stratégies de protection des cultures alternatives à la lutte chimique. L’adoption de pratiques plus favorables à la biodiversité dans les agroécosystèmes pourrait contribuer...

Migration and population dynamics are important in organisms that provide ecosystem services as they determine the occurrence of individuals in a given place at a given time, which, in turn, determines the efficiency of the service provided. To design appropriate landscape management strategies to improve the efficiency of biological control, it is...

Population structure of pests and beneficial species is an important issue when designing management strategies to optimize ecosystem services. In this study, we investigated for the first time the population structure at a continental scale of two migratory species of hoverflies providing both pest regulation and pollination services [Episyrphus b...

Bayesian assignment probabilities for k = 2, K = 3 and K = 4. Each vertical line represents an individual, and colours indicate the proportion of an individual’s genotype assigned to a particular lineage, individuals are sorted by overwintering strategy and sampling site. (DOCX)

Expected (He) and observed (Ho) heterozygosity at each locus in the six groups. Significance differences between these values (determined with an α of 0.05 and using a sequential Bonferroni correction (Rice 1989)) are indicated by asterisks. Loci for which at least two groups showed significant departure from Hardy–Weinberg equilibrium were discard...

Winter ecology of natural enemies has a great influence on the level and efficiency of biological control at spring. The hoverfly Episyrphus balteatus (DeGeer) (Diptera: Syrphidae) is one of the most important natural predators of crop aphids in Europe. Three different overwintering strategies coexist in this species which makes it a good model in...