Publications by authors named "Bianca B Perren"
Unicellular free-living microbial eukaryotes of the order Arcellinida (Tubulinea; Amoebozoa) and Euglyphida (Cercozoa; SAR), commonly termed testate amoebae, colonise almost every freshwater ecosystem on Earth. Patterns in the distribution and productivity of these organisms are strongly linked to abiotic conditions-particularly moisture availability and temperature-however, the ecological impacts of changes in salinity remain poorly documented. Here, we examine how variable salt concentrations affect a natural community of Arcellinida and Euglyphida on a freshwater sub-Antarctic peatland.
View Article and Find Full Text PDFDiatoms, combined with a multiproxy study of lake sediments (organic matter, N, δ15N, δ13C, biogenic silica, grain size, Cladocera and chironomids, Alnus pollen) from Lone Spruce Pond, Alaska detail the late-glacial to Holocene history of the lake and its response to regional climate and landscape change over the last 14.5 cal ka BP. We show that the immigration of alder (Alnus viridis) in the early Holocene marks the rise of available reactive nitrogen (Nr) in the lake as well as the establishment of a primarily planktonic diatom community.
View Article and Find Full Text PDFArticle Synopsis
- Arctic lakes have shown significant ecological changes due to 20th-century climate change, and this study compares these changes with alpine and boreal lakes while considering factors like reactive nitrogen deposition.
- The research synthesized 52 diatom sediment records from various ecosystems in North America and Greenland, revealing that diatom diversity in arctic and alpine lakes significantly increased in the 20th century compared to previous centuries.
- Findings indicate that changes in diatom diversity aren’t strongly linked to specific environmental parameters, leading the authors to use Principal Components Analysis to understand the broader impacts of factors like nitrogen deposition and temperature trends.