Earthworms provide key soil functions that favour many positive ecosystem services. These services are important for agroecosystem sustainability but can be degraded by intensive cultural practices such as use of pesticides. Many literature reports have investigated the effect of pesticides on earthworms. Here, we review those reports to assess the relevance of the indicators of earthworm response to pesticides, to assess their sensitivity to pesticides, and to highlight the remaining knowledge gaps. We focus on European earthworm species and products authorised in Europe, excluding natural compounds and metals. We consider different organisation levels: the infra-individual level (gene expression and physiology), the individual and population levels (life-history traits, population density and behaviour) and the community level: community biomass and density. Our analysis shows that earthworms are impacted by pesticides at all organisation levels. For example, pesticides disrupt enzymatic activities, increase individual mortality, decrease fecundity and growth, change individual behaviour such as feeding rate and decrease the overall community biomass and density.Insecticides and fungicides are the most toxic pesticides impacting survival and reproduction, respectively.

Soil organisms provide crucial ecosystem services that support human life. However, little is known about their diversity, distribution, and the threats affecting them. Here, we compiled a global dataset of 60 sampled earthworm communities from over 7000 sites in 56 countries to predict patterns in earthworm diversity, abundance, and biomass. We identify the environmental drivers shaping these patterns. Local species richness and abundance typically peaked at higher latitudes, while biomass peaked in the tropics, patterns opposite to those observed in aboveground organisms. Similar to many aboveground taxa, climate variables were more important in shaping earthworm communities than soil properties or habitat 65 cover. These findings highlight that, while the environmental drivers are similar, conservation strategies to conserve aboveground biodiversity might not be appropriate for earthworm diversity, especially in a changing climate.

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International audienceSoil invertebrates are assumed to play a major role in ecosystem dynamics, since they are involved in soil functioning. Functional traits represent one of the main opportunities to bring new insights into the understanding of soil invertebrate responses to environmental changes. They are properties of individuals which govern their responses to their environment. As no clear conceptual overview of soil invertebrate trait definitions is available, we first stress that previously-described concepts of trait are applicable to soil invertebrate ecology after minor modification, as for instance the inclusion of behavioural traits. A decade of literature on the use of traits for assessing the effects of the environment on soil invertebrates is then reviewed. Trait-based approaches may improve the understanding of soil invertebrate responses to environmental changes as they help to establish relationships between environmental changes and soil invertebrates. Very many of the articles are dedicated to the effect of one kind of stress at limited spatial scales. Underlying mechanisms of assembly rules were sometimes assessed. The patterns described seemed to be similar to those described for other research fields (e.g. plants). The literature suggests that trait-based approaches have not been reliable over eco-regions. Nevertheless, current work gives some insights into which traits might be more useful than others to respond to a particular kind of environmental change. This review also highlights methodological advantages and drawbacks. First, trait-based approaches provide complementary information to taxonomic ones. However the literature does not allow us to differentiate between trait-based approaches and the use of a priori functional groups. It also reveals methodological shortcomings. For instance, the ambiguity of the trait names can impede data gathering, or the use of traits at a species level, which can hinder scientific interpretation as intra-specific variability is not taken into account and may lead to some biases. To overcome these shortcomings, the last part aims at proposing some solutions and prospects. It concerns notably the development of a trait database and a thesaurus to improve data management

Soil ecosystems support a plethora of intertwined biophysical and biochemical processes. Soil structure plays a central role in the formation and maintenance of soil biological activity by providing a diversified habitat for soil organisms and determining the movement and transport of the resources on which they rely. At the same time, the formation and preservation of soil structure and fertility is also strongly linked to soil biological activity through feedback loops. In most soil ecosystems, soil biological activity and associated processes are concentrated in the soil located around living plant roots and influenced by root activity, an environment known as the rhizosphere. Consequently, among the wide array of soil life forms, plants play a dominant role in the regulation of many soil processes. In this paper, we illustrate the functional complexity of soil ecosystems using specific examples of root–soil interactions and associated processes. Through examples taken from the literature, we examine the origins and variations in soil physical, chemical, and biological properties and their impact on root growth. Next, we consider how the response of root systems to their environment affects resource acquisition by plants. Finally, we describe how the concept of root functional architecture can improve the integration of research advances from fields operating as independent disciplines and improve our understanding of soil ecosystems.