Journalartikel

Jahr der Veröffentlichung: 2017

Seiten: 423-431

Zeitschrift: Journal of Soils and Sediments

Bandnummer: 17

Heftnummer: 2

ISSN: 1439-0108

eISSN: 1614-7480

DOI Link: https://doi.org/10.1007/s11368-016-1530-2

Verlag: Springer

Abstract: 
Alpine ecosystems on the Qinghai-Tibetan Plateau are sensitive to global climatic changes. However, the effects of temperature change resulting from global warming or seasonal variation on soil N availability in those ecosystems are largely unknown.We therefore conducted a N-15 tracing study to investigate the effects of various temperatures (5-35 A degrees C) on soil gross N transformation rates in an alpine meadow (AM) soil on the Qinghai-Tibetan Plateau. A natural secondary coniferous forest (CF) soil from the subtropical region was chosen as a reference to compare the temperature sensitivity of soil gross N transformation rates between alpine meadow and coniferous forest.Our results showed that increasing temperature increased gross N mineralization and NH4 (+) immobilization rates and overall enhanced N availability for plants in both soils. However, both rates in the CF soil were less sensitive to a temperature change from 5 to 15 A degrees C compared to the AM soil. In both soils, different N retention mechanisms could have been operating with respect to changing temperatures in the different climatic regions. In the CF soil, the absence of NO3 (-) production at all incubation temperatures suggests that in the subtropical soil which is characterized by high rainfall, an increase in N availability due to increasing temperature could be completely retained in soils. In contrast, the AM soil may be vulnerable to N losses with respect to temperature changes, in particular at 35 A degrees C, in which higher nitrification rates were coupled with lower NH4 (+) and NO3 (-) immobilization rates.Our results suggest that increased soil temperature arising from global warming and seasonal variations will most likely enhance soil N availability for plants and probably increase the risk of N losses in the alpine meadow on the Qinghai-Tibetan Plateau.

Harvard-Zitierstil: Wang, J., Zhang, J., Müller, C. and Cai, Z. (2017) Temperature sensitivity of gross N transformation rates in an alpine meadow on the Qinghai-Tibetan Plateau, Journal of Soils and Sediments, 17(2), pp. 423-431. https://doi.org/10.1007/s11368-016-1530-2

APA-Zitierstil: Wang, J., Zhang, J., Müller, C., & Cai, Z. (2017). Temperature sensitivity of gross N transformation rates in an alpine meadow on the Qinghai-Tibetan Plateau. Journal of Soils and Sediments. 17(2), 423-431. https://doi.org/10.1007/s11368-016-1530-2