Birch Bog on Anthropogenically Transformed Raised Bogs. A Case Study from Pomerania (Poland)

Birch bog is formed on the margins of or within raised bogs, on secondary habitats. The study aim was to understand the vegetation and mycological diversity of birch bog on the background of habitat conditions on raised bogs subject to anthropogenic changes, including 15 areas located on seven bogs. Two of the analyzed areas were located on a peat bog not subject to human impact. Phytosociological and mycosociological relevés were taken and substrate analyses were carried out (pH, humidity, N-NH4, N-NO2, N-NO3 and P-PO4). Based on habitat predictors, two area groups were distinguished, differing primarily in humidity. More humid habitats were present on the margins of bogs, and were characterized by lower acidity and higher N-NH4 and P-PO4 abundance. Despite the fact they were enriched by runoffs from the neighboring arable fields, this was not always reflected in the plant and fungi species richness. Quercus robur appeared on less humid habitats, which may be a symptom of unfavorable changes toward habitat drying. In the majority of cases, changes in the habitat independent of the birch patches located and the human impact type are not yet reflected in the vegetation. However, they may be indicated by the fungal diversity, highest in former peat extraction pits, and lowest in pristine peat.

Response of shallow subterranean freshwater amphipods to habitat drying

The ability of three amphipods that occupy shallow subterranean habitats in the lower Potomac Basin of the US (hypotelminorheic), which often dry out seasonally, to withstand desiccation by burrowing in clay was investigated. Both Crangonyxshoemakeri, a wetland species, and Stygobromustenuis, a subterranean species, burrowed in clay in the laboratory after surface water was removed. Gammarusminus, a spring species, did not. All three species exhibited behavioral changes as the habitat dried out.