13 research outputs found
Mechanistic effect modeling of earthworms in the context of pesticide risk assessment: Synthesis of the FORESEE Workshop.
Earthworms are important ecosystem engineers, and assessment of the risk of plant protection products towards them is part of the European environmental risk assessment (ERA). In the current ERA scheme, exposure and effects are represented simplistically and are not well integrated, resulting in uncertainty when applying the results to ecosystems. Modeling offers a powerful tool to integrate the effects observed in lower tier laboratory studies with the environmental conditions under which exposure is expected in the field. This paper provides a summary of the FORESEE Workshop ((In)Field Organism Risk modEling by coupling Soil Exposure and Effect) held January 28‐30, 2020 in Düsseldorf, Germany. This workshop focussed on toxicokinetic‐toxicodynamic (TKTD) and population modeling of earthworms in the context of environmental risk assessment. The goal was to bring together scientists from different stakeholder groups to discuss the current state of soil invertebrate modeling, explore how earthworm modeling could be applied to risk assessments, and in particular how the different model outputs can be used in the tiered ERA approach. In support of these goals, the workshop aimed at addressing the requirements and concerns of the different stakeholder groups to support further model development. The modeling approach included four submodules to cover the most relevant processes for earthworm risk assessment: Environment, Behavior (feeding, vertical movement), TKTD, and Population. Four workgroups examined different aspects of the model with relevance for: Risk assessment, earthworm ecology, uptake routes, and cross‐species extrapolation and model testing. Here, we present the perspectives of each workgroup and highlight how the collaborative effort of participants from multidisciplinary backgrounds helped to establish common ground. In addition, we provide a list of recommendations for how earthworm TKTD modeling could address some of the uncertainties in current risk assessments for plant protection products
Standard methods for the assessment of structural and functional diversity of soil organisms: a review
International audienceThe lack of standardized methods to study soil organisms prevents comparisons across data sets and the development of new global and regional experiments and assessments. Moreover, standardized methods are needed to evaluate the impact of anthropogenic stressors, such as chemicals, on soil organism communities in the regulatory context. The goal of this contribution is to summarize current methodological approaches to measure structural and functional diversity of soil organisms, and to identify gaps and methodological improvements so as to cross data sets generated worldwide. This is urgently needed because several currently ongoing regional and global soil biodiversity studies are not coordinated with one another in terms of methodology, including database development. Therefore, we evaluated the standard methods to sample, identify, determine, and assess soil organisms currently applied or proposed, using well-accepted criteria such as ecological relevance; practicability of usage in terms of resources, time, and costs; and the level of standardization. Methods addressing both the structure and the functions of soil organisms (populations or communities) are included, with a special focus on new molecular methods based on nucleic acid extraction and further analyses by polymerase chain reaction (PCR)-based approaches for microorganisms and invertebrates. We particularly highlight the activities of the Technical Committee (TC) 190 of the International Organization for Standardization (ISO) because ISO guidelines are legally accredited by many national or international authorities when they put conservation laws and regulations into practice. Finally, we propose detailed recommendations regarding gaps in the available set of standards, in order to identify a list of new methods to be standardized. We propose to organize this whole process under the Global Soil Biodiversity Initiative (GSBI) in order to ensure a truly global approach for the assessment of soil biodiversity
A fauna de minhocas em florestas em regeneração e habitats antropogênicos na região costeira do Paraná
The aim of this study was to evaluate abundance, biomass and diversity of earthworms in the southern coast region of the Mata AtlÔntica biodiversity hotspot. Aátotal of 51ástudy sites in pastures, banana monocultures, mixed agroforestry systems, secondary forests in succession and old-growth forests near the coast of Paranß, Brazil, were evaluated. Each site was sampled once. Species richness of the earthworms was generally low and varied little between sites. At all sites except for one, the peregrine species Pontoscolex corethrurus (Glossoscolecidae) strongly dominated. Three other peregrine species, Amynthas corticis, Amynthas gracilis (Megascolecidae) and Ocnerodrilus occidentalis (Ocnerodrilidae), were frequent in moist sites. No autochthonous species were found. Abundance and biomass of earthworms varied strongly within and between sites (0–338 individuals m-2, 0–96 g m-² fresh weight). Pastures had significantly lower abundance than all other sites. The forest sites had similar earthworm abundance and biomass, with a tendency to be higher in younger succession stages. The coastal plain region has been strongly altered by human activities. Reasons for the lack of any autochthonous species and the dominance of one peregrine species require further investigation.As part of the German-Brazilian research project SOLOBIOMA earthworms were sampled at 51 sites in the southern Atlantic forest of Brazil. Aims of the study were to enhance knowledge of the earthworm fauna in the “biodiversity hotspot” Mata Atlântica and to evaluate abundance, biomass and diversity of earthworms with regard to the biological quality of sites. Study sites were pastures, banana monocultures, agroforestry systems, secondary forests in succession and old-growth forests near the coast of Paraná. Each site was sampled once. Species richness of the earthworms was generally low. At all except one sites Pontoscolex corethrurus (Glossoscolecidae), a peregrine species, strongly dominated. Two other peregrine species Amynthas sp. (Megascolecidae) and Ocnerodrilus occidentalis (Ocnerodrilidae) were frequent in moist sites. No autochthonous species was sampled. Abundance and biomass of earthworms varied strongly within and between sites (0 - 338 ind m-2, 0 - 70 g fresh weight (FW) m-²). Pastures did differ significantly from all other sites. All forest sites showed a surprisingly similar earthworm fauna in terms of abundance and also biomass. Abundance and biomass were higher in the younger succession stages than in the older ones. The results indicate that the whole region has since a long time been strongly altered by man. For unknown reasons all autochthonous species had disappeared and been replaced by the peregrine species Pontoscolex corethrurus. By its high abundance and biomass this species determines the decomposition and nutrient cycles, but nothing is known about the long-term effect of such a biodiversity reduction on ecosystem services.
Index terms: Atlantic Rain Forest, earthworms, peregrine species, secondary forestsO objetivo deste estudo foi avaliar a abundância, a biomassa e a diversidade de minhocas, na região costeira sul do "hotspot" de biodiversidade Mata Atlântica. Um total de 51 locais foram avaliados em pastagens, monoculturas de banana e sistemas agroflorestais de banana com palmito e florestas secundárias próximos à costa do Estado do Paraná. Cada local foi amostrado apenas uma vez. A riqueza de espécies de minhocas, de modo geral, foi baixa e variou pouco entre os locais. Em todos os locais, exceto um, predominou a espécie peregrina Pontoscolex corethrurus (Glossoscolecidae). Não foram encontradas espécies nativas em nenhum local. Três outras espécies peregrinas, Amynthas corticis, Amynthas gracilis (Megascolecidae) e Ocnerodrilus occidentalis (Ocnerodrilidae), foram frequentes em locais úmidos. A abundância e a biomassa das minhocas variaram muito, dentro e entre os sítios amostrais (0-338 indivíduos m-2, 0–96 g m-2 de massa fresca). Nas pastagens, observou-se menor abundância do que nos demais ecossistemas. As florestas apresentaram abundância e biomassa similares, sendo que estágios mais jovens da regeneração apresentaram abundância e biomassa mais alta. A planície litorânea já foi fortemente alterada por atividades antrópicas. As razões da falta de espécies nativas e da predominância de uma espécie peregrina, na região, necessitam ser mais pesquisadas
Soil water availability strongly alters the community composition of soil protists
Drought and heavy rainfall are contrasting conditions expected to result from increasingly extreme weather during climate change; and both scenarios will strongly affect the functioning of soil systems. However, little is known about the specific responses of soil microorganisms, whose functioning is intimately tied to the magnitude of the water-filled pore space in soil. Soil heterotrophic protists, being important aquatic soil organisms are considered as key-regulators of microbial nutrient turnover. We investigated the responses of distinct protist taxa to changes in soil water availability (SWA) using a modified enumeration technique that enabled quantification of protist taxa up to genus level. Our study revealed a non-linear shift of protist abundance with decreasing SWA and this became apparent at a maximum water-filled pore size of <= 40 mu m. Generally, taxa containing large specimen were more severely affected by drought, but responses to either drought or rewetting of soils were not uniform among taxa. Changes in water availability may thus affect the functioning of key taxa and soil ecosystems long before aboveground drought effects become apparent. (C) 2014 Elsevier GmbH. All rights reserved
Statistical Results and Implications of the Enchytraeid Reproduction Ringtest.
Abstract not availableJRC.I-Institute for Health and Consumer Protection (Ispra
Cryptic Species in Ecotoxicology
The advent of genetic methods has led to the discovery of an increasing number of species that previously could not be distinguished from each other on the basis of morphological characteristics. Even though there has been an exponential growth of publications on cryptic species, such species are rarely considered in ecotoxicology. Thus, the particular question of ecological differentiation and the sensitivity of closely related cryptic species is rarely addressed. Tackling this question, however, is of key importance for evolutionary ecology, conservation biology, and, in particular, regulatory ecotoxicology. At the same time, the use of species with (known or unknown) cryptic diversity might be a reason for the lack of reproducibility of ecotoxicological experiments and implies a false extrapolation of the findings. Our critical review includes a database and literature search through which we investigated how many of the species most frequently used in ecotoxicological assessments show evidence of cryptic diversity. We found a high proportion of reports indicating overlooked species diversity, especially in invertebrates. In terrestrial and aquatic realms, at least 67% and 54% of commonly used species, respectively, were identified as cryptic species complexes. The issue is less prominent in vertebrates, in which we found evidence for cryptic species complexes in 27% of aquatic and 6.7% of terrestrial vertebrates. We further exemplified why different evolutionary histories may significantly determine cryptic species' ecology and sensitivity to pollutants. This in turn may have a major impact on the results of ecotoxicological tests and, consequently, the outcome of environmental risk assessments. Finally, we provide a brief guideline on how to deal practically with cryptic diversity in ecotoxicological studies in general and its implementation in risk assessment procedures in particular. Environ Toxicol Chem 2023;00:1-26. & COPY; 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC