其他摘要：As a potent fertilizer, reactive nitrogen plays an important role in Arctic ecosystems. Since the Arctic is a nutrient limited environment, changes in nitrogen deposition can have severe impacts on local ecosystems. To quantify the amount of nitrogen deposition through snow- and rain events, precipitation sampling was performed at Zeppelin station, Svalbard, from November 2009 until May 2011. The samples were analysed for NO3-, nss-SO42- and NH4+ concentrations, and the deposition of single precipitation events was calculated using precipitation observations from Ny-Ålesund. The majority of observed events showed concentrations ranging from 0.01 to 0.1 mg L-1 N for NO3- and NH4+ and 0.02 to 0.3 mg L-2 S for nss-SO42-. The majority of calculated deposition was in the range between 0.01 to 0.1 mg m-2 N for NO3- and NH4+ and 0.02 – 0.3 mg m-2 S for nss-SO42-. The budget was controlled by strong deposition events, caused by long lasting precipitation episodes that lasted for several days and which had raised concentrations of nitrogen and sulphur. Three future scenarios of increasing precipitation in the Arctic were considered. The results showed that deposition is mainly controlled by the amount of precipitation, which leads to the conclusion that increased precipitation might cause increases in deposition of the same magnitude.
Loading...
