Shallow-water benthic macroinvertebrate community of the limnic part of a lowland Polish dam reservoir

Abstract

Biodiversity, abundance and taxonomic composition of shallow-water zoobenthos were studied in the Włocławek Dam Reservoir (the lower Vistula River, central Poland). The following habitats located near the shore were studied:(1) sandy bottom in the flooded part of the reservoir; (2) sandy bottom close to the main riverine flow in the reservoir and (3) organic-rich bottom covered by a thick layer of plant remnants in a shallow, isolated cove. In each habitat we investigated two sites (ca. 0.5 and 1 m depth). Also examined was the bottom of a phytolittoral site (sandy bottom, with elodeids and nympheids, 1 m depth), located in the flooded zone. In general, the bottom fauna was highly diverse and abundant in these habitats. The highest biodiversity (38 taxa, Shannon-Wiener index ¼ 4.3) was found on the bottom rich in organic matter. However, the zoobenthos abundance in this habitat was comparatively low, probably due to periodical oxygen deficiencies. The highest density of bottom fauna (430,000 individuals per m 2 ), accompanied by its high biodiversity, occurred at the phytolittoral site. The benthic community of the organic-rich sediments was the most distinct, with many taxa occurring exclusively in this area. The composition of the bottom fauna, from the two sandy habitats and phytolittoral, also differed from one another. The differences in taxonomic composition between the shallower and deeper sites were less pronounced. Lower densities at the shallower sandy sites and a very high variability of taxonomic composition among particular samples from these sites indicated lower stability of their environmental conditions. These were certainly due to water level fluctuations and/or destructive wave action. On the other hand, no such differences were found between the sites of various depths from the organic-rich sediments, showing that this substratum provided better protection against adverse hydrodynamical factors.

Settlement preferences of leeches (Clitellata: Hirudinida) for different artificial substrates

“…Much has been written about their use as a tool in the assessment of aquatic environment quality (De Pauw et al, 1994;Czerniawska-Kusza, 2004;MacDonald et al, 2012;Loke et al, 2014) or biomass production of phyto and zoobenthos (Moura et al, 2007;Plá & Alveal, 2012). In relation to inland waters, research has mainly focused on their habitat-creation role and concerns entire groups of benthic fauna (De Pauw et al, 1986, De Pauw et al, 1994Czerniawska-Kusza, 2004;Poznańska et al, 2009;Czarnecka et al, 2009). Studies about the preferences of particular species are still rare and tend to focus on sessile organisms (Czarnołęski et al, 2004;Kobak, 2004;Kobak & Januszewska, 2006;Porter & Marsden, 2008;Richards & Beger, 2011;Braccia et al, 2014;Spagnolo et al, 2014).…”

Hydrological and anthropogenic influence in the Gilgel Gibe I reservoir (Ethiopia) on macroinvertebrate assemblages

“…When the reservoir water level reaches its maximum, the surrounding vegetation is submerged. As a result, the substratum of the littoral zone is covered with plants, which provides protection to macroinvertebrates from predators and also serves as a food source (Poznanska et al 2009). During high water levels, cattle did not often enter the littoral zone to drink because they could easily access water near the grazing fields.…”

“…Macroinvertebrate communities in the littoral zone also vary due to water level fluctuations (Hynes 1961). The vegetation in the littoral zone of reservoirs plays an important role for macroinvertebrate communities by providing protection from predators and excessive water current and serving as a food source (Poznanska et al 2009); however, young reservoirs can have poor macroinvertebrate communities (Meiling et al 2007, Jorcin andNogueira 2008).…”

Effect of substratum drying on the survival and migrations of a freshwater pulmonate snail Planorbarius corneus (Linnaeus, 1758)

“…Lodge, 1985;Underwood et al, 1992;Costil & Clement, 1996), which is strongly affected by water level fluctuations (e.g. Coops et al, 2003;Furey et al, 2004;Poznańska et al, 2009). The effect of water level changes on fauna and flora depends on their range, duration, regularity and frequency, as well as on season, basin morphometry, bottom type and climate (e.g.…”