Simone Wengrat

Universität Konstanz | Uni-Konstanz · Department of Biology

The type material of Cymbella schubartii was studied in order to clarify the differences and similarities within the complex of Encyonopsis species observed in southeastern Brazilian water bodies. Detailed examination using light and scanning electron microscopy of modern populations led us to propose two new Encyonopsis species, which are here des...

Biodiversity changes in response to eutrophication, climate variability and species invasions. These pressures have been shown to reduce community heterogeneity at various scales; however, how productivity drives homogenization patterns in a community of primary producers, such as diatoms, has not been studied. Using a dataset with good temporal re...

Tropical reservoirs are sensitive to eutrophication but long-term impacts of impoundment on their productivity and biota are poorly understood. Here, we employ a palaeolimnological approach to assess whether ecological baselines can be defined for reservoirs, and examine the challenges and management implications. We studied the environmental histo...

High Arctic ecosystems and Indigenous livelihoods are tightly linked and exposed to climate change, yet assessing their sensitivity requires a long-term perspective. Here, we assess the vulnerability of the North Water polynya, a unique sea ice ecosystem that sustains the world’s northernmost Inuit communities and several keystone Arctic species. W...

Many lake ecosystems that have been severely disturbed by eutrophication, have also experienced large human efforts to restore "natural" conditions. However, the trajectories and the extent of recovery of these lake ecosystems are still poorly understood. In many shallow lakes, recovery was often delayed and counter-clockwise hysteretic. Here, we s...

Local communities and individual species jointly contribute to the overall beta diversity in metacommunities. However, it is mostly unknown whether the local contribution (LCBD) and the species contribution (SCBD) to beta diversity can be predicted by local and regional environmental characteristics and by species traits and taxonomic relatedness,...

A diatom survey was carried out in the largest reservoir of the city of São Paulo. Twenty-four phytoplankton, 15 periphyton, and 12 surface sediment samples covering a gradient of trophic states were collected in 2009 and 2010. Overall, 67 taxa were sampled (60 species and varieties and seven identified at the genus level). Four species are new rec...

Type material of Encyonema angustecapitatum Krammer was investigated to establish the identity of several Brazilian Encyonema populations. In order to elucidate the differences and similarities of that species complex, morphological features under light and scanning electron microscopy were detailed. Notes on their distribution were also discussed....

Ecological preferences and distribution of Aulacoseira species in southeastern Brazilian reservoirs with varying trophic states were studied. One hundred and fourteen plankton samples (winter and summer) from 57 sites located in 16 reservoirs were analysed. Ten water quality parameters were measured. Ten Aulacoseira species were identified using li...

Synedra rumpens var. fusa was originally described by Patrick, but there are only a few subsequent records of this variety in the literature. Analysis of samples from Brazilian reservoirs containing a morphologically similar taxon led us to the analysis of the type material of S. rumpens var. fusa, performed using light (LM) and scanning electron m...

Synedra rumpens var. fusa was originally described by Patrick, but there are only a few subsequent records of this variety in the literature. Analysis of samples from Brazilian reservoirs containing a morphologically similar taxon led us to the analysis of the type material of S. rumpens var. fusa, performed using light (LM) and scanning electron m...

Ecological preferences and distribution of Aulacoseira species in southeastern Brazilian reservoirs with varying trophic states were studied. One hundred and fourteen plankton samples (winter and summer) from 57 sites located in 16 reservoirs were analysed. Ten water quality parameters were measured. Ten Aulacoseira species were identified using li...

Aim: The study aimed at (a) contributing to a spatial evaluation of the Billings Complex water quality; (b) associating information on the geochemistry of the surface sediments; and (c) providing, based on previous studies, a temporal evaluation of the Complex’s water quality since the Pinheiros River pumping restriction; Methods: sampling was perf...