13 research outputs found
Impact of Evapotranspiration Formulations at Various Elevations on the Reconnaissance Drought Index
Evaluation of future climate using SDSM and secondary data (TRMM and NCEP) for poorly gauged catchments of Uganda: the case of Aswa catchment
Evaluation of Gridded Precipitation Data for Driving SWAT Model in Area Upstream of Three Gorges Reservoir
Temporal Hydrologic Alterations Coupled with Climate Variability and Drought for Transboundary River Basins
Quantifying effects of conservation practices on non-point source pollution in the Miyun Reservoir Watershed, China
Abundances and potential activities of nitrogen cycling microbial communities along a chronosequence of a glacier forefield
Glacier forefields are ideal ecosystems to study the development of nutrient cycles as well as single turnover processes during soil development. In this study, we examined the ecology of the microbial nitrogen (N) cycle in bulk soil samples from a chronosequence of the Damma glacier, Switzerland. Major processes of the N cycle were reconstructed on the genetic as well as the potential enzyme activity level at sites of the chronosequence that have been ice-free for 10, 50, 70, 120 and 2000 years. In our study, we focused on N fixation, mineralization (chitinolysis and proteolysis), nitrification and denitrification. Our results suggest that mineralization, mainly the decomposition of deposited organic material, was the main driver for N turnover in initial soils, that is, ice-free for 10 years. Transient soils being ice-free for 50 and 70 years were characterized by a high abundance of N fixing microorganisms. In developed soils, ice-free for 120 and 2000 years, significant rates of nitrification and denitrification were measured. Surprisingly, copy numbers of the respective functional genes encoding the corresponding enzymes were already high in the initial phase of soil development. This clearly indicates that the genetic potential is not the driver for certain functional traits in the initial phase of soil formation but rather a well-balanced expression of the respective genes coding for selected functions