Catchment land cover as a proxy for macroinvertebrate assemblage structure in Carpathian Mountain streams

Abstract

We compared land cover, riparian vegetation, and instream habitat characteristics with stream macroinvertebrate assemblages in 25 catchments in the Carpathian Mountains in Central Europe. This study area was particularly selected because of its diverse history of forest and agricultural ecosystems linked to geopolitical dynamic, which provide a suite of unique landscape scale, land cover settings in one ecoregion. Canonical Correspondence Analysis (CCA) showed that variation in composition and structure of macroinvertebrate assemblages was primarily related to four land cover types, and not to riparian or instream habitat. These were the portions in the catchment areas of (1) broadleaved forest, (2) fine-grained agricultural landscape mosaic with scattered trees (e.g., pre-industrial cultural landscape), (3) mixed forest, and (4) natural grassland without trees. Principal Component Analysis (PCA) suggested that land cover types and stream channel substrates co-varied. The PCA also showed that chemical variables, including organic carbon, had higher values in the agricultural landscape compared to natural forests. The major source of variation among taxa in streams was higher abundance of Diptera in agricultural landscapes and of Plecoptera, Coleoptera, Trichoptera, and Amphipoda in forests. Gastropoda and Oligochaeta were more abundant in open, fine-grained agricultural landscape mosaics with scattered trees. Ephemeroptera taxa were quite indifferent to these gradients in catchment land cover, but showed a tendency of being more abundant in the pre-industrial cultural landscape. Our findings suggest that land cover can be used as a proxy of the composition and structure of macroinvertebrate assemblages. This means that land use management at the catchment scale is needed for efficient conservation and recovery of stream invertebrate communities.

Multiple factors and thresholds explaining fish species distributions in lowland streams

“…Categorical (S, slow; F, fast) catchment) (Degerman et al, 2007;Schinegger et al, 2012;Törnblom et al, 2011), and because they respond individually to environmental change (Olden et al, 2006;Parmesan and Yohe, 2003). To achieve a good conservation status and identify appropriate restoration and conservation measures, it is therefore necessary to first identify the factors limiting the distribution of individual species and to evaluate the effects of interactions among environmental drivers on species distribution (Guisan et al, 2013).…”

Influence of selected environmental factors on macroinvertebrates in mountain streams

“…Our survey confirmed the results of [45] because both the nature of the river bed, which was reflected by the values of the HQA and HMS indices, as well as the physical parameter determined the structure of macroinvertebrate communities. According to [46], human land use and land cover within the Carpathian catchments are reflected in the instream macroinvertebrate distribution. Ephemeroptera, Plecoptera, Trichoptera and Amphipoda are numerous in less human-affected forested catchments in the Carpathian mountain streams.…”

Assemblages of stonefly larvae (Plecoptera) in the area of small hydrological structures, in the streams of the Kamienica Nawojowska river basin (The Beskid Sądecki)

“…The taxonomic wealth of stoneflies and larval abundance are influenced by the trophic qualities of water, which are shaped, among other things, by the management of the river basin and coastal area (Kopacz, Twardy, 2006). According to Törnblom et al (2011) stoneflies prefer watercourses of wooded river basins. Hence, the highest densities of larvae were recorded in the sections located in the wooded river basin and in midstream of the watercourses, especially in Nowa Wieś (facility N) and Łabowiec (facility L).…”

“…Hence, the highest densities of larvae were recorded in the sections located in the wooded river basin and in midstream of the watercourses, especially in Nowa Wieś (facility N) and Łabowiec (facility L). The type of river basin cover and the position of the site in the longitutinal profile of the watercourse also influence the trophic structure of macroinvertebrate groupings (Törnblom et al, 2011). Medhurst et al (2010) report that shredders and gatherers prevail in watercourses of wooded basins.…”