Litter decomposition can be reduced by pesticide effects on detritivores and decomposers: Implications for tropical stream functioning

Understanding which factors affect the process of leaf litter decomposition is crucial if we are to predict changes in functioning stream ecosystems as a result human activities. One major activity with known consequences on streams agriculture, particular concern tropical regions, where forests being rapidly replaced by crops. While pesticides potential drivers reduced rates observed agricultural streams, their specific effects performance decomposers and detritivores mostly unknown. We used microcosm experiment examine individual joint an insecticide (chlorpyrifos) fungicide (chlorothalonil) survival growth (Anchytarsus, Hyalella Lepidostoma), aquatic hyphomycetes (AH) sporulation rate, taxon richness, assemblage structure, rates. Our results revealed detrimental detritivore (which were due strongest for Hyalella), AH richness microbial (mostly response fungicide). Total was especially when combined, suggesting that they operated differently additive. Importantly, greater single-species treatments than 3-species mixture, indicating species loss may exacerbate ecosystem functioning.