Standard methods for the assessment of structural and functional diversity of soil organisms: A review

Abstract

The 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. Integr Environ Assess Manag 2018;14:463-479. © 2018 SETAC.

Oppia nitensC.L. Koch, 1836 (Acari: Oribatida): Current Status of Its Bionomics and Relevance as a Model Invertebrate in Soil Ecotoxicology

“…Standardization efforts ensure comparisons between toxicity tests, providing specific requirements or guidance associated with different aspects of the tests (e.g., species, materials, test parameters, and endpoints). A significant advantage of standardization is that it validates the test method (including the requirements or guidance therein prompts an in-depth approach involving discussion among scientists within the field, the consideration of practical aspects ensuring broader applicability of the method, and ring-testing to ensure conformity and comparability of the proposed method (Römbke et al 2018). This in-depth approach ensures applicability of the test method across numerous chemical substances (e.g., new and existing), and within various field exposure scenarios, to either characterize risk or assist with developing remediation requirements.…”

State of the Art of Triad-Based Ecological Risk Assessment: Current Limitations and Needed Implementations in the Case of Soil Diffuse Contamination

“…Another well-represented approach in ecology LoE consisted in measuring the impact of contamination on soil functioning. The preservation of key soil functions was identified as a primary protection goal and their evaluation has a recognized place in risk assessment of contaminated soils (van Gestel et al, 2009;Römbke et al, 2018). Functional assays such as basal respiration, organic matter decomposition or bait lamina feeding activity were used to estimate the deterioration of key soil processes, like nutrient turnover, to due chemical contamination.…”

Editorial: Microbial Ecotoxicology

“…Given how rapidly research in microbial ecotoxicology and related methods are developing, it is a challenge to identify, standardize, and normalize the most relevant protocols for operational and regulatory applications. Indeed, standards are required (Philippot et al, 2012 ; Römbke et al, 2018 ) and large-scale studies are needed to perform meta-analyses and inform models to establish reference baselines, such as “normal operating ranges” of microbial functions (EFSA Scientific Committee, 2016 ). Moreover, one may not exclude the fact that the microbial world, which is most often invisible to the human eye, remains largely unknown to the general public and, even more worryingly, to a wide range of stakeholders and deciders.…”