Aquatic community structure in Mediterranean edge-of-field waterbodies as explained by environmental factors and the presence of pesticide mixtures

Abstract

Studies addressing the predicted effects of pesticides in combination with abiotic and biotic factors on aquatic biota in ditches associated with typical Mediterranean agroecosystems are scarce. The current study aimed to evaluate the predicted effects of pesticides along with environmental factors and biota interactions on macroinvertebrate, zooplankton and phytoplankton community compositions in ditches adjacent to Portuguese maize and tomato crop areas. Data was analysed with the variance partitioning procedure based on redundancy analysis (RDA). The total variance in biological community composition was divided into the variance explained by the multi-substance potentially affected fraction [(msPAF) arthropods and primary producers], environmental factors (water chemistry parameters), biotic interactions, shared variance, and unexplained variance. The total explained variance reached 39.4% and the largest proportion of this explained variance was attributed to msPAF (23.7%). When each group (phytoplankton, zooplankton and macroinvertebrates) was analysed separately, biota interactions and environmental factors explained the largest proportion of variance. Results of this study indicate that besides the presence of pesticide mixtures, environmental factors and biotic interactions also considerably influence field freshwater communities. Subsequently, to increase our understanding of the risk of pesticide mixtures on ecosystem communities in edge-of-field water bodies, variations in environmental and biological factors should also be considered.

Environmental DNA metabarcoding reveals comparable responses to agricultural stressors on different trophic levels of a freshwater community

“…It is likely that some of these effects on phytoplankton and bacteria communities have been caused by food web cascades. Indeed, previous research showed that even under stress from pesticide mixtures, biotic interactions played a major role in the structuring of plankton communities (Pereira et al, 2018 ). Similarly, responses to nutrient pressure by fertilizer in macroinvertebrates may also partly be caused by cascade reactions, such as the aforementioned changes in food availability.…”

Neonicotinoid Insecticides in Surface Water, Groundwater, and Wastewater Across Land‐Use Gradients and Potential Effects

“…To evaluate the combined environmental and biological factors that influence plankton abundance, a multivariate statistical analysis described by Pereira et al (2018) was used to more accurately determine the potential responses of planktonic taxa to neonicotinoids beyond simple linear relationships. Any meaningful interpretations of these data, however, could not be made because of the limited spatiotemporal resolution of the samples containing synchronous measurements of plankton population sizes and neonicotinoid concentrations (i.e., 3 discrete sampling events for 10 lakes in Ramsey County during 1 yr).…”

Ecological health evaluation of rivers based on phytoplankton biological integrity index and water quality index on the impact of anthropogenic pollution: A case of Ashi River Basin

“…Current research on IBIs mainly focuses on fish (Cooper et al, 2018), macroinvertebrates (Wahl et al, 2019), plankton (Zhang et al, 2019), and bacteria (Li et al, 2017(Li et al, , 2018. These aquatic biological community structures are important markers of water pollution and eutrophication; therefore, they are often used to evaluate the damage to and health of aquatic ecosystems (Pereira et al, 2018). Phytoplankton rapidly respond to environmental changes, and their community structure accurately reflects the short-term effects of anthropogenic and natural disturbances on aquatic ecosystems (Busseni et al, 2019).…”