Macroinvertebrate community responses to land use: a trait-based approach for freshwater biomonitoring in Mongolia

Abstract

Land-use practices in Mongolia can lead to environmental degradation and consequently affect the structure and function of biological communities. The main aim of this study was to determine land-use effects on freshwater macroinvertebrate communities based on their response to grazing and mining, using a trait-based approach (TBA). The functional structure of macroinvertebrate communities was examined using 86 categories of 16 traits. A total of 13 physical and chemical variables were significantly different among the levels of land-use intensity. Significant declines in functional diversity were observed with increased land-use intensity. The community weighted mean of 19 trait categories for 11 traits varied significantly among different levels of land-use intensity. Traits were significantly explained by environmental variables across a land-use intensity gradient. Water temperature, gravel, nitrate, silt, and cobble were the main predictor variables and explained 28% of the total variance of the trait variation. The functional structure of the macroinvertebrate community was strongly related to environmental conditions. The TBA is an important method in assessing disturbance responses in freshwater communities of steppe and taiga regions, such as in Mongolia and other countries in Central Asia and will be useful in finding best management practices for conserving aquatic ecosystems. Handling editor: Checo Colón-GaudElectronic supplementary material The online version of this article (https://doi.

Human Impact Induces Shifts in Trophic Composition and Diversity of Consumer Communities in Small Freshwater Ecosystems

“…18.3-18.4) may also be associated with the higher habitat structural and functional complexity provided by macrophytes. Habitat heterogeneity promotes a greater variety of food sources for these groups and serves as a refuge from predation [18].…”

“…18.7b). Gravel and send mining increase water turbidity, sediment deposition, metal contamination, and habitat fragmentation [18,102], which may have negative consequences for predatory fish [8,14,21,103]. For instance, changes in visibility due to increased sediment deposition may decrease feeding success of predatory fish [8,21].…”

“…These variations may depend on the nature of disturbances. Increased sediment loading and dissolved organic carbon from agricultural practices or gravel mining [19] could favour decomposers [18,19]. Water contamination with toxic pollutants arising from waste input, agriculture, gravel exploitation, may instead have negative effects on decomposers.…”

“…Particularly vulnerable to anthropogenic pressures are small water bodies (SWB) because of their low water volume and close connection to adjacent agricultural fields and urban areas [10][11][12]. The most evident examples of anthropogenic stressors in SWB and their surroundings include agricultural land use, urbanization, gravel and sand mining, waste inputs, and associated changes to nutrient cycling, sedimentation, altered water temperature and acidity, which affect resource quantity and quality for consumers, as well as their interactions with predators [7,8,[13][14][15][16][17][18][19][20][21].…”

Functional trait variability supports the use of mean trait values and identifies resistance trade‐offs for marine macroalgae

“…Beukhof et al, 2019; Henseler et al, 2019), microbes (for review, see Krause et al, 2014) and insects (e.g. Yadamsuren et al, 2020). These significant gains in understanding propelled by the use of TBE across taxon, questions and ecosystems provide strong motivation for propagating its use across even more broadly.…”