PuSH - Publication Server of Helmholtz Zentrum München

Wang, C.* ; Chen, Z.* ; Unteregelsbacher, S.* ; Lu, H.* ; Gschwendtner, S. ; Gasche, R.* ; Kolar, A.* ; Schloter, M. ; Kiese, R.* ; Butterbach-Bahl, K.* ; Dannenmann, M.*

Climate change amplifies gross nitrogen turnover in montane grasslands of Central Europe both in summer and winter seasons.

Glob. Change Biol. 22, 2963-2978 (2016)
Postprint DOI PMC
Open Access Green
The carbon and nitrogen rich soils of montane grasslands are exposed to above average warming and to altered precipitation patterns as a result of global change. In order to investigate the consequences of climatic change for soil nitrogen turnover, we translocated intact plant-soil mesocosms along an elevational gradient, resulting in an increase of the mean annual temperature by approx. 2°C while decreasing precipitation from approx. 1500 to 1000 mm. Following three years of equilibration, we monitored the dynamics of gross nitrogen turnover and ammonia oxidizing bacteria (AOB) and archaea (AOA) in soils over an entire year. Gross nitrogen turnover and gene levels of AOB and AOA showed pronounced seasonal dynamics. Both summer and winter periods equally contributed to cumulative annual N turnover. However, highest gross N turnover and abundance of ammonia oxidizers were observed in frozen soil of the climate change site, likely due to physical liberation of organic substrates and their rapid turnover in the unfrozen soil water film. This effect was not observed at the control site, where as soil freezing did not occur due to a significant insulating snowpack. Climate change conditions accelerated gross nitrogen mineralization by 250% on average. Increased N mineralization significantly stimulated gross nitrification by AOB rather than by AOA. However, climate change impacts were restricted to the 2-6 cm topsoil and rarely occurred at 12-16 cm depth, where generally much lower N turnover was observed. Our study shows that significant mineralization pulses occur under changing climate, which is likely to result in soil organic matter losses with their associated negative impacts on key soil functions. We also show that N cycling processes in frozen soil can be hot moments for N turnover and thus are of paramount importance for understanding seasonal patterns, annual sum of N turnover and possible climate change feedbacks.
Altmetric
Additional Metrics?
Edit extra informations Login
Publication type Article: Journal article
Document type Scientific Article
Corresponding Author
Keywords Aoa ; Aob ; Freeze-thaw ; Frozen Soil ; Gross N Mineralization ; Gross Nitrification ; Montane Grassland; Ammonia-oxidizing Archaea; Rain-forest Soils; Nitrification Rates; N Mineralization; N2o Emissions; Gas Fluxes; Temperature Sensitivity; Microbial Communities; Species Composition; Semiarid Grassland
ISSN (print) / ISBN 1354-1013
e-ISSN 1365-2486
Quellenangaben Volume: 22, Issue: 9, Pages: 2963-2978 Article Number: , Supplement: ,
Publisher Wiley
Publishing Place Hoboken
Non-patent literature Publications
Reviewing status Peer reviewed