title: Vegetation net primary productivity and its response to climate change during 2001-2008 in the Tibetan Plateau.
abstract: Alpine ecosystems are highly sensitive to global climate changes. The Tibetan Plateau is one of the areas that are most sensitive to global climate change. Increases in temperature and changes in precipitation can impact the plateau's ecosystem productivity. Net primary productivity (NPP) is one of the most important factors in the carbon cycle of terrestrial ecosystems. In this paper, a light-use-efficiency model was used to estimate the net primary productivity in the Tibetan Plateau. The model is based on a 1-km×1-km-resolution map of vegetation type, multi-temporal 500-m-resolution MODIS data and daily meteorological data. The spatial distribution pattern and dynamic change of the annual NPP from 2001 to 2008 are analyzed. Then, we analyzed the response of the NPP to temperature and precipitation changes. The results show that the mean annual NPP of alpine ecosystems in the Tibetan Plateau is equal to 0.472 Pg C and that the NPP exhibits significant seasonal and interannual variation due to the combined effects of temperature and precipitation changes. Finally, to analyze the effect of temperature and precipitation on the inter-annual change of the NPP, the correlation coefficient between temperature, precipitation and the NPP was computed. It was found that the relations among air temperature, precipitation and the NPP in the Tibetan Plateau region are different. The annual average temperature increase had a significantly positive effect on the vegetation NPP (R(2)=0.83). In contrast, the annual precipitation changes had a weakly negative effect on the vegetation NPP (R(2)=0.373).
authors.affiliation: Satellite Environment Center, Ministry of Environment Protection, Beijing 100094, China. gao_yanhua@163.com
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Gao
authors.forename: Xu
authors.initials: X
authors.lastname: Zhou
authors.forename: Qiao
authors.initials: Q
authors.lastname: Wang
authors.forename: Changzuo
authors.initials: C
authors.lastname: Wang
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Zhan
authors.forename: Liangfu
authors.initials: L
authors.lastname: Chen
authors.forename: Junxia
authors.initials: J
authors.lastname: Yan
authors.forename: Ran
authors.initials: R
authors.lastname: Qu
mesh_terms: D057231:Climate Change; D017753:Ecosystem; D008962:Models, Theoretical; D018521:Plant Physiological Phenomena; D012621:Seasons; D013696:Temperature; D018609:Tibet