Response of Seasonally Frozen Ground to Climate Changes in the Northeastern Qinghai-Tibet Plateau

	Response of Seasonally Frozen Ground to Climate Changes in the Northeastern Qinghai-Tibet Plateau
	Zhao, ZH; Fu, RY; Liu, JJ; Dai, LC; Guo, XW; Du, YG; Hu, ZM; Cao, GM
刊名	FRONTIERS IN ENVIRONMENTAL SCIENCE
	2022
卷号	10
英文摘要	The effects of climate change on permafrost have been well documented in many studies, whereas the effect of climate change on seasonally frozen ground (SFG) is still poorly understood. We used the observed daily freeze depth of SFG and environmental factors data from the period 2007-2016 to examine the seasonal and inter-annual variation of SFG. We quantitatively evaluated the effects of environmental factors on SFG using a boosted regression tree analysis. The results show that, on a seasonal scale, the lower layer soil frost starts freezing in mid-November, with the maximum freeze depth occurring in late March (209 cm), and then begins to thaw in both the lower and upper layers. We identified four stages of the freeze-thaw cycle: the non-frozen phase, initial freezing, deep freezing, and thawing. Furthermore, the thawing process of SFG mainly took place in the upper layer, but the freezing rate of the lower layer from mid-November to early February was similar to the thawing rate of late April to late June. On the inter-annual scale, the maximum freeze depth showed a significant increasing trend (p < 0.05). However, the freeze-thaw duration declined significantly (p < 0.05), which was correlated with the decrease in the period when surface soil temperature is below 0 degrees C. The mean soil temperature and soil heat flux were the most important environmental indicators affecting seasonal variation of SFG depth, and the cumulative negative air and soil temperatures were the dominant factors affecting inter-annual variation of maximum freeze depth. Our results might provide insight into predicting hydrological and ecological responses to future climate change in frozen-ground regions.
内容类型	期刊论文
源URL	[http://210.75.249.4/handle/363003/61155]
专题	西北高原生物研究所_中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Zhao, ZH,Fu, RY,Liu, JJ,et al. Response of Seasonally Frozen Ground to Climate Changes in the Northeastern Qinghai-Tibet Plateau[J]. FRONTIERS IN ENVIRONMENTAL SCIENCE,2022,10.
APA	Zhao, ZH.,Fu, RY.,Liu, JJ.,Dai, LC.,Guo, XW.,...&Cao, GM.(2022).Response of Seasonally Frozen Ground to Climate Changes in the Northeastern Qinghai-Tibet Plateau.FRONTIERS IN ENVIRONMENTAL SCIENCE,10.
MLA	Zhao, ZH,et al."Response of Seasonally Frozen Ground to Climate Changes in the Northeastern Qinghai-Tibet Plateau".FRONTIERS IN ENVIRONMENTAL SCIENCE 10(2022).