EFSA identified the monitoring of soil microorganisms as relevant for pesticides environmental risk assessment and stressed the need for novel tests to assess the toxicity of pesticides to soil microorganisms. This issue is addressed by the ARISTO project, the European industry-academia network for revising and advancing the assessment of the soil microbial toxicity of pesticides. ARISTO is an International Training Network (ITN) funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement. Within the ARISTO project, a PhD scholarship in soil microbial ecology is available for a period of 36 months.
In soil, microorganisms are abundant and diverse. They accomplish key functions supporting ecosystem services and interact with other organisms living in soils. The exposure to pesticides can impact the abundance, diversity and activity of soil microorganisms as well as their interactions with macro-organisms. Although soil organisms are exposed to complex mixtures of pesticide residues, most of the studies to assess the ecotoxicity of pesticide towards soil microorganisms are still performed as single substance tests, not considering complex mixtures or interactions with macro-organisms.
Within this context, the two main objectives of the PhD student are (1) to identify and to develop methods, procedures and tools to assess the toxicity of pesticide mixtures on soil microorganisms and (2) to assess the toxicity of pesticides on soil microorganisms and potential interactions with terrestrial macro-organisms. This work will be carried out using a lab-to-field experimental design with a two-tier scenario of exposure. Two microbial guilds (AOM and AMF) and their possible interactions with soil macro-organisms (arthropods or earthworms) will be studied in detail. Specifically, the PhD student will perform lab experiments using planted soil microcosms and field experiments for assessing the impact of pesticide mixtures on the abundance (qPCR), diversity (amplicon sequencing) and activity of these two microbial guilds, and use advanced biostatistics and bioinformatics analytical methods. The experimental process will involve collaboration with other PhD fellows within the project to provide a comprehensive scheme for assessing the ecotoxicity of complex mixtures of active substances of chemical and/or natural origin.
For further information on the PhD scholarship see here.