Annual ecosystem respiration is resistant to changes in freeze-thaw periods in semi-arid permafrost

NWIPB OpenIR

	Annual ecosystem respiration is resistant to changes in freeze-thaw periods in semi-arid permafrost
	Wang, Qi; Lv, Wangwang; Li, Bowen; Zhou, Yang; Jiang, Lili; Piao, Shilong; Wang, Yanfen; Zhang, Lirong; Meng, Fandong; Liu, Peipei; Hong, Huan; Li, Yaoming; Dorji, Tsechoe; Luo, Caiyun; Zhang, Zhenhua; Ciais, Philippe; Penuelas, Josep; Kardol, Paul; Zhou, Huakun; Wang, Shiping
	2020
发表期刊	GLOBAL CHANGE BIOLOGY
卷号	26 期号:4
摘要	Warming in cold regions alters freezing and thawing (F-T) of soil in winter, exposing soil organic carbon to decomposition. Carbon-rich permafrost is expected to release more CO2 to the atmosphere through ecosystem respiration (Re) under future climate scenarios. However, the mechanisms of the responses of freeze-thaw periods to climate change and their coupling with Re in situ are poorly understood. Here, using 2 years of continuous data, we test how changes in F-T events relate to annual Re under four warming levels and precipitation addition in a semi-arid grassland with discontinuous alpine permafrost. Warming shortened the entire F-T period because the frozen period shortened more than the extended freezing period. It decreased total Re during the F-T period mainly due to decrease in mean Re rate. However, warming did not alter annual Re because of reduced soil water content and the small contribution of total Re during the F-T period to annual Re. Although there were no effects of precipitation addition alone or interactions with warming on F-T events, precipitation addition increased total Re during the F-T period and the whole year. This decoupling between changes in soil freeze-thaw events and annual Re could result from their different driving factors. Our results suggest that annual Re could be mainly determined by soil water content rather than by change in freeze-thaw periods induced by warming in semi-arid alpine permafrost.
关键词	ecosystem respiration freeze-thaw events number and frequency of freeze-thaw cycles precipitation addition semi-arid with ice-poor permafrost Tibetan Plateau warming gradient
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/60408
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Wang, Qi,Lv, Wangwang,Li, Bowen,et al. Annual ecosystem respiration is resistant to changes in freeze-thaw periods in semi-arid permafrost[J]. GLOBAL CHANGE BIOLOGY,2020,26(4).
APA	Wang, Qi.,Lv, Wangwang.,Li, Bowen.,Zhou, Yang.,Jiang, Lili.,...&Wang, Shiping.(2020).Annual ecosystem respiration is resistant to changes in freeze-thaw periods in semi-arid permafrost.GLOBAL CHANGE BIOLOGY,26(4).
MLA	Wang, Qi,et al."Annual ecosystem respiration is resistant to changes in freeze-thaw periods in semi-arid permafrost".GLOBAL CHANGE BIOLOGY 26.4(2020).