Resilience of Energy and CO2 Exchange to a Summer Heatwave in an Alpine Humid Grassland on the Qinghai-Tibetan Plateau

	Resilience of Energy and CO2 Exchange to a Summer Heatwave in an Alpine Humid Grassland on the Qinghai-Tibetan Plateau
	Zhang, Fawei 1,2; Cao, Guangmin 1
刊名	polish journal of environmental studies
	2017
卷号	26 期号:1 页码:385-394
关键词	climate change vegetation photosynthesis ecosystem respiration evapotranspiration boosted regression trees
英文摘要	summer heatwaves are expected to be much more frequent and severe with negative effects on terrestrial ecosystem water and carbon budgets, while the impacts on alpine grasslands remain poorly understood. here we analyzed eddy flux and meteorological dataset of a seven-day (july 26 to august 1) summer heatwave in an alpine humid grassland in northeastern qinghai-tibetan plateau in 2015. compared with pre-heatwave, only diurnal ecosystem respiration (res) increased by 30.7%, evidently (p < 0.001) during the heatwave. diurnal sensible heat fluxes (h) and latent heat fluxes (let) increased by 18.1% (p = 0.08) and 27.5% (p = 0.02) from 9:00 to 16:00. the heatwave did not lead to substantial increments of daily h and daily let, while daily bowen ratio (h/let) decreased a little (p = 0.07). daily net ecosystem co2 exchange increased by 76.7% (p = 0.03), mainly resulting from remarkable growth in daily res (p<0.001) and undetectable fluctuation in daily gross primary production (gpp) (p = 0.13). daily ecosystem water use efficiency (gpp/evapotranspiration) decreased by 20.8%. the little difference of energy and co2 fluxes between pre-heatwave and post-heatwave indicated strong resilience to the summer heatwave in the alpine humid grassland. our results revealed that the present-day summer heatwave exerted a limited influence on energy exchange and vegetation photosynthetic activity but did stimulate ecosystem respiration, which would provide a positive feedback to climate warming with more carbon efflux from alpine grassland.
WOS标题词	science & technology ; life sciences & biomedicine
类目[WOS]	environmental sciences
研究领域[WOS]	environmental sciences & ecology
关键词[WOS]	climate extremes ; mountain grasslands ; carbon-cycle ; ecosystem ; productivity ; china ; temperature ; variability ; reduction ; impacts
收录类别	SCI
语种	英语
WOS记录号	WOS:000394830000041
内容类型	期刊论文
源URL	[http://ir.nwipb.ac.cn/handle/363003/6831]
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
作者单位	1.Chinese Acad Sci, Northwest Inst Plateau Biol, Key Lab Adaptat & Evolut Plateau Biota, Xining 810001, Qinghai, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Fawei,Cao, Guangmin. Resilience of Energy and CO2 Exchange to a Summer Heatwave in an Alpine Humid Grassland on the Qinghai-Tibetan Plateau[J]. polish journal of environmental studies,2017,26(1):385-394.
APA	Zhang, Fawei,&Cao, Guangmin.(2017).Resilience of Energy and CO2 Exchange to a Summer Heatwave in an Alpine Humid Grassland on the Qinghai-Tibetan Plateau.polish journal of environmental studies,26(1),385-394.
MLA	Zhang, Fawei,et al."Resilience of Energy and CO2 Exchange to a Summer Heatwave in an Alpine Humid Grassland on the Qinghai-Tibetan Plateau".polish journal of environmental studies 26.1(2017):385-394.