Experiments were carried out in soil microcosms with the treatment of pesticide formulations—imidacloprid, benomyl, and metribuzin in single and tenfold application rates. For additional stimulation of microorganisms, a starch–mineral mixture was added to some variants. For all samples, high-throughput sequencing on the Illumina MiSeq platform of the V4 (16S rRNA) and ITS1 (18S rRNA) fragments was carried out. As a result, it was possible to establish the characteristic changes in the structure of the soil fungal and bacterial communities under pesticides application. The application of pesticides was accompanied by dramatic shifts in alfa-diversity of the fungal community. The phylum Basidiomycota was likely to be involved in the degradation of pesticides. The changes in the relative abundance of the genera Terrabacter, Kitasatospora, Streptomyces, Sphingomonas, Apiotrichum, Solicoccozyma, Gamsia, and Humicola can be proposed as an indicator of pesticide contamination. It is suggested to use these markers for large-scale assessment of the effect of pesticides on soil microbial communities instead of classical integral methods, including within the framework of state registration of pesticides. It is also recommended to research the effect of pesticides on the soil microbiome during artificially initiated successions using the additional source of carbon.
The predisposition of the region to groundwater pollution by pesticides depends on climatic and soil factors, characteristics of the aquifer system, the type of the territory management, physicochemical properties of used pesticides and timing of their application. The applying of computer models for vulnerability assessment allows to consider the influence of factors affecting the migration of substances through the soil profile. Agricultural districts of Russia were grouped by basic climatic parameters -average annual temperatures and rainfall. 9 large regions with uniform climatic characteristics were obtained. The combination of climatic and soil parameters of each region made up a standard scenario, which was implemented as input files to the pesticide fate model PEARL. As an indicator of the vulnerability of groundwater to pesticide contamination, we used the predicted weighted average annual pesticide concentrations in leachate at a depth of 1 m. Calculations showed the highest vulnerability was in Nizhny Novgorod, Moscow, Pskov, Vladivostok, intermediate one - in Novosibirsk, and the lowest ones - in Kurgan, Saratov, Kursk and Krasnodar.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.