Pesticides and earthworms. A review

Abstract

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.

Harmful or useful? A case study of the exotic peregrine earthworm morphospecies Pontoscolex corethrurus

“…At this concentration, P. corethrurus individuals were not found to avoid the contaminated soil. As with other contaminants and earthworm species (Pelosi et al, 2014), the bioavailability of chemicals in soils is highly dependent on soil properties (Van Gestel and Weeks, 2004). Therefore, the effects of trace elements on P. corethrurus are likely to depend on soil type, moisture, temperature and many other soil characteristics.…”

Effects of the herbicides benfluralin, metribuzin and propyzamide on the survival and weight of earthworms (Octodrilus complanatus)

“…According to Mosleh et al (2003), even if the importance of earthworms in ecotoxicological studies is well recognized, there is still a need for further data on the toxicity of specific pesticides to such non-target organisms. Most published ecotoxicological studies on earthworms have focused on metals, while the effects of pesticides have been less studied (Pelosi et al 2014). Results from previous studies indicate that pesticides uptake by earthworms cannot be generalized between species and that the influence of species traits can vary depending on the nature of the studied chemicals (Carter et al 2016) and exposure temperatures (Velki and Ecimovic 2015).…”

Distribution et structure des communautés de vers de terre et leur corrélation avec des éléments traces métalliques (ETM) le long des bordures de l’autoroute du Nord en Côte-d’Ivoire

“…L'abondance élevée et la bonne répartition de ces espèces endogées dans ce milieu pourraient se justifier par une excellente capacité d'adaptation. Selon Rossi (200 3) et Pelosi et al (2014), cette adaptation pourrait être un changement de comportement en réponse aux contraintes du milieu, telles la pollution et la recherche de la nourriture. Ainsi, certains vers de terre filiformes appartenant à la famille des Eudrilidae sont inféodés aux racines, puis d'autres suivent le gradient d'infiltration de l'eau dans les couches profondes du sol en filtrant les particules organiques (Blouin et al, 2013).…”