Effect of mesohabitats on responses of invertebrate community structure in streams under different land uses

Abstract

Riparian vegetation is one of the most important abiotic components determining the water flow pattern in lotic ecosystems, influencing the composition, richness, and diversity of invertebrates. We have identified whether differences in the structure of the assemblages of invertebrates between riffles and pools may influence the responses of fauna to the effects of land use. In addition, we investigated which fauna metrics are responsible for the differentiation between riffles and pools in streams subject to different land uses. During the dry season of 2012, the main substrates of riffles and pools were sampled (Surber collector) from nine streams within forest, pasture, and urban areas. Principal component analysis (PCA) and Permanova showed differences in the set of environmental variables between streams and mesohabitats. The first PCA axis distinguished the forest and pasture streams from the urban area streams and was related to variables indicative of nutrient enrichment and land use, while the second axis was formed by velocity flow and by the quantities of ultrafine and coarse sand, which distinguished the riffles and pools of the streams. The faunal composition distinguished the streams in pasture and forest areas from the urban streams. Riffles and pools were not concordant in the representation of the invertebrate fauna, indicating the importance of sampling both mesohabitats in the types of streams investigated. The richness, taxonomic composition, and relative abundance of families of Ephemeroptera, Plecoptera, and Trichoptera showed robust responses in riffles to the effects of environmental changes, while in pools, only the richness showed a significant response. It was possibly concluded that riffles were more sensitive in detecting the effects of land use. The information from this study help to understand how the community of invertebrates and the types of habitats in streams may be affected by anthropogenic impacts.

Variables de hábitat que regulan la estructura de las comunidades de macroinvertebrados en corrientes de montaña del Oriente antioqueño (Colombia)

“…De acuerdo con Roldán-Pérez y Ramírez-Restrepo (2022), el oxígeno es fundamental para varios procesos vitales como la respiración, oxidación de la materia orgánica y nitrificación. Tal como lo describen Dias da Silva et al (2015), su concentración en los mesohábitats ocurre en función de las condiciones hidráulicas creadas por la combinación de la velocidad, características de los sustratos y la profundidad. Es así como el ingreso de oxígeno por subsidio atmosférico, que sería mayor en un mesohábitat como los rápidos, afectaría procesos funcionales clave en este tipo de ecosistemas.…”

Diversidade de presas e predadores (Insecta) em mesohabitats de córregos de Cerrado

“…A natureza do substrato está entre os maiores determinantes da biota aquática (Gaines et al, 1989). Modificações das características naturais dos córregos, como a retirada da vegetação ciliar pode influenciar diretamente a composição dos substratos do leito, ocorrendo, por exemplo, aumento da presença de sedimento arenoso e pouca liteira (Silva et al, 2015). Assim, essas alterações podem causar a diminuição da diversidade de presa e predadores, modificando a estrutura da composição desses organismos.…”

Impact of urbanization on the water quality of the Uberaba River and tributaries

“…CONAMA Resolution nº 357/2005 addresses the limits of such parameters and classifies in quality water bodies, besides setting guidelines for their classification (BRASIL, 2005). However, this monitoring type analyzes momentary conditions in the environment without showing the effect of contaminants on the ecosystem over time ROSA;.…”