Christian Mougin

Differences in sensitivity between earthworms and enchytraeids exposed to two commercial fungicides

The use of pesticides in crop fields may have negative effects on soil Oligochaeta Annelida, i.e., earthworms and enchytraeids, and thus affect soil quality. The aim of this study was to assess the effects of two commercial fungicide formulations on the earthworm Aporrectodea caliginosa and the enchytraeid Enchytraeus albidus in a natural soil. The fungicides were Cuprafor micro® (copper oxychloride), commonly used in organic farming, and Swing Gold® (epoxiconazole and dimoxystrobin), a synthetic fungicide widely used in conventional farming to protect cereal crops. Laboratory experiments were used to assess the survival, biomass loss and avoidance behaviour. No lethal effect was observed following exposure to the copper fungicide for 14 days, even at 5000mgkg-1 of copper, i.e. 650 times the recommended dose (RD). However, a significant decrease in biomass was observed from 50mgkg-1 of copper (6.5 times the RD) for A. caliginosa and at 5000mgkg-1 of copper (650 times the RD) for E. albidus. These sublethal effects suggest that a longer period of exposure would probably have led to lethal effects. The EC50 avoidance for the copper fungicide was estimated to be 51.2mgkg-1 of copper (6.7 times the RD) for A. caliginosa, and 393mgkg-1 of copper (51 times the RD) for E. albidus. For the Swing Gold® fungicide, the estimated LC50 was 7.0 10-3mLkg-1 (6.3 times the RD) for A. caliginosa and 12.7 10-3mLkg-1 (11.0 times the RD) for E. albidus. No effect on biomass or avoidance was observed at sublethal concentrations of this synthetic fungicide. It was concluded that enchytraeids were less sensitive than earthworms to the two commercial fungicides in terms of mortality, biomass loss and avoidance behaviour. Therefore we discuss the different strategies possibly used by the two Oligochaeta species to cope with the presence of the pesticides were discussed, along with the potential consequences on the soil functions.

How to Integrate Experimental Research Approaches in Ecological and Environmental Studies: AnaEE France as an Example

Human activities have altered continental ecosystems worldwide and generated a major environmental crisis, prompting urgent societal questions on how to best produce goods while at the same time securing sustainable ecological services and raising needs to better understand and predict biodiversity and ecosystems dynamics under global changes. To tackle these questions, experimentation on ecosystems is necessary to improve our knowledge of processes and to propose scientifically sound management strategies. Experimental platforms able to manipulate key factors of global change and including state of the art observation methodologies are available worldwide but how to best integrate them has been rarely addressed. Here, we present and discuss the case of the national research infrastructure AnaEE France dedicated to the study of continental ecosystems and designed to congregate complementary experimental approaches in order to facilitate their access and use through a range of distributed and shared services. The conceptual design of AnaEE France includes five modules. Three modules gather experimental facilities along a gradient of experimental control ranging from highly controlled Ecotron facilities, semi-natural field mesocosms to in natura experimental sites covering major continental ecosystems (forests, croplands, grasslands and lakes). In addition, AnaEE France also includes shared instruments that can be implemented in experiments and analytical platforms specifically dedicated to environmental biology. To promote reuse of data, generalize results and improve predictive models, AnaEE France further gathers modelling and information systems. The implementation of AnaEE France allowed for mutual synergies, improved the technical skills, stimulated new experiments and helped our scientific community to enter into the big data sharing era.

Biochem-Env: a platform of biochemistry for research in environmental and agricultural sciences

Biochemical indicators are potent tools to assess ecosystem functioning under anthropic and global pressures. Nevertheless, additional work is needed to improve the methods used for the measurement of these indicators, and for a more relevant interpretation of the obtained results. To face these challenges, the platform Biochem-Env aims at providing innovative and standardized measurement protocols, as well as database and information system favoring result interpretation and opening. Its skills and tools are also offered for expertise, consulting, training, and standardization. In addition, the platform is a service of a French Research Infrastructure for Analysis and Experimentation on Ecosystems, for research in environmental and agricultural sciences.

Fate and impact of pesticides: new directions to explore

The consequences of the environmental contamination by pesticides on human and ecosystem health are of major concern. A strong research effort is needed to better understand the deleterious effects of pesticides, to reduce uncertainties concerning these potential effects, and to inform public policies and citizens. This effort has to focus on different scientific fields of research such as toxicology, ecotoxicology, epidemiology, and human and social sciences. The finality is to propose solutions to reduce the risks related to the dispersion of pesticides in the environment and to decrease their harmful impacts on biodiversity, ecosystem functions, and human health. Improving the human and ecosystem exposure measurements remains a challenge for pesticide risk assessment strategies. Standardized and integrated protocols are needed for in situ monitoring of pesticides in various ecosystems. This can allow for more realistic ecotoxicological studies as well as epidemiological surveys on the impacts of pesticides on the environment and human health. Integrating new results at different levels of organization including human activities is critical to address the difficult question of long-term effects of pesticides at low concentrations and for compound mixtures. It is therefore necessary to rely on new tools andmethods, e.g., sensors, biomarkers, bio-omics, analytical platforms, dedicated to ecotoxicological approaches, predictive toxicology, and epidemiological studies. Designing cropping systems to reduce pesticide use and/or impacts at different spatial scales and levels of organization has become a clear research orientation in Europe. In France, the Ecophyto plan called for a decrease in pesticide use. Although this objective is far to be reached, this recent policy has launched many research programs in the last 10 years. Significant progresses have been made regarding the conception and assessment of low input cropping system performances. Alternative agricultural practices such as conservation tillage, selected crop varieties, biological regulations of bioagressors at the plot, farm, and landscape scales may significantly contribute to decrease the pesticide pressure. Improving our knowledge of pesticide transfers outside from the treated plots remains necessary before promoting measures to reduce pesticide dispersion at the watershed scale. Local processes regulating the interactions between the soil, air, vegetation, and water have to be thoroughly understood. Field observations, experimental studies, and modeling approaches addressing the dispersion of pesticides should consider both the plot and catchment scales in a variety of landscapes—from rural to peri-urban areas—and under a variety of pedoclimatic conditions. Ecological infrastructures such as buffer zones can be used in these different landscapes to reduce the dispersion. However, a quantitative assessment of their efficiency and the integration of their functioning in the pesticide transfer models are required. Modeling pesticide fate and transport as well as their biological effects on living organisms requires a detailed knowledge of physicochemical and biological processes at microscales. These processes occur in soil porosity colonized by soil microorganisms, within plant organs and tissues, at the interface between soil, plant, air, or water. Innovative approaches for the study of these processes coupled to the Responsible editor: Philippe Garrigues

How to assess the feeding activity in ecotoxicological laboratory tests using enchytraeids

The risk assessment of pesticides on soil fauna is an issue to protect agroecosystem sustainability. Enchytraeids are recognized as relevant soil bioindicators of chemical stress in agroecosystems. In laboratory, the reproduction test was found to be sensitive to reveal chemical impacts on enchytraeids. However, it does not allow to assess the impacts on ecological functions in which enchytraeids are involved. The objectives of this study were (i) to explore the feasibility of the bait-lamina test with enchytraeids under laboratory conditions and (ii) to compare its sensitivity with the Enchytraeid Reproduction Test. We exposed individuals of Enchytraeus albidus to two commercial formulations of fungicides widely used in Europe. The EC50 reproduction for the Swing® Gold (50xa0gxa0L−1 epoxiconazole and 133xa0gxa0L−1 dimoxystrobin) and the Cuprafor micro® (50% copper oxychloride) were respectively estimated at 1.66u2009±u20090.93 times the recommended dose and >u2009496xa0mgxa0kg−1 of copper. However, no impact was found on the feeding activity of enchytraeids. The bait-lamina test thus appeared less sensitive than the Enchytraeid Reproduction Test to the tested fungicides. Despite that, this test which is achievable under laboratory conditions and allows assessing indirect effects of pesticides is quick, cheap, and easy to perform. It would deserve to be used to explore longer-exposure effects through the repeated addition of bait-lamina sticks.

BRC4Env, a network of Biological Resource Centres for research in environmental and agricultural sciences

The Biological Resource Centre for the Environment BRC4Env is a network of Biological Resource Centres (BRCs) and collections whose leading objectives are to improve the visibility of genetic and biological resources maintained by its BRCs and collections and to facilitate their use by a large research community, from agriculture research to life sciences and environmental sciences. Its added value relies on sharing skills, harmonizing practices, triggering projects in comparative biology, and ultimately proposing a single-entry portal to facilitate access to documented samples, taking into account the partnership policies of research institutions as well as the legal frame which varies with the biological nature of resources. BRC4Env currently includes three BRCs: the Centre for Soil Genetic Resources of the platform GenoSol, in partnership with the European Conservatory of Soil Samples; the Egg Parasitoids Collection (EP-Coll); and the collection of ichthyological samples, Colisa. BRC4Env is also associated to several biological collections: microbial consortia (entomopathogenic bacteria, freshwater microalgae…), terrestrial arthropods, nematodes (plant parasitic, entomopathogenic, animal parasitic...), and small mammals. The BRCs and collections of BRC4Env are involved in partnership with academic scientists, as well as private companies, in the fields of medicinal mining, biocontrol, sustainable agriculture, and additional sectors. Moreover, the staff of the BRCs is involved in many training courses for students from French licence degree to Ph.D, engineers, as well as ongoing training.

RECOTOX, a French initiative in ecotoxicology-toxicology to monitor, understand and mitigate the ecotoxicological impacts of pollutants in socioagroecosystems

RECOTOX is a cross-cutting initiative promoting an integrated research to respond to the challenges of monitoring, understanding, and mitigating environmental and health impacts of pesticides in agroecosystems. The added value of RECOTOX is to develop a common culture around spatial ecotoxicology including the whole chain of pressure-exposure-impact, while strengthening an integrated network of in natura specifically equipped sites. In particular, it promotes transversal approaches at relevant socioecological system scales, to capitalize knowledge, expertise, and ongoing research in ecotoxicology and, to a lesser extent, environmental toxicology. Thus, it will open existing research infrastructures in environmental sciences to research programs in ecotoxicology of pesticides.

Aporrectodea caliginosa , a relevant earthworm species for a posteriori pesticide risk assessment: current knowledge and recommendations for culture and experimental design

Ecotoxicological tests with earthworms are widely used and are mandatory for the risk assessment of pesticides prior to registration and commercial use. The current model species for standardized tests is Eisenia fetida or Eisenia andrei. However, these species are absent from agricultural soils and often less sensitive to pesticides than other earthworm species found in mineral soils. To move towards a better assessment of pesticide effects on non-target organisms, there is a need to perform a posteriori tests using relevant species. The endogeic species Aporrectodea caliginosa (Savigny, 1826) is representative of cultivated fields in temperate regions and is suggested as a relevant model test species. After providing information on its taxonomy, biology, and ecology, we reviewed current knowledge concerning its sensitivity towards pesticides. Moreover, we highlighted research gaps and promising perspectives. Finally, advice and recommendations are given for the establishment of laboratory cultures and experiments using this soil-dwelling earthworm species.