青藏高原1981-2000年植被净初级生产力对气候变化的响应

The Response of Vegetation Net Primary Productivity to Climate Change during 1981-2000 in the Tibetan Plateau

基于分辨率为0．1^o×0．1^o的植被、土壤和气象数据，利用大气-植被相互作用模型（AVIM2）模拟研究了青藏高原1981-2000年植被净初级生产力（NPP）对气候变化的响应。结果表明：青藏高原近20年自然植被（森林、草地和灌木）受气温和降水量增加的影响，NPP总量呈现上升趋势。灌木和森林NPP总量分别以每年1．14％和0．88％的速度增加，均达到统计上的显著性水平。草地NPP上升趋势不如灌木和森林显著。降水量变化对森林和草地NPP的影响高于气温变化对它们的影响，而降水量变化对灌木的影响则小于气温变化影响。总的区域平均来看，尽管1981-2000年青藏高原年平均净辐射通量略有降低，但由于平均气温以0．058℃·a^-1的速率增加，且降水量略有增长，降水量与气温的共同作用使得青藏高原植被NPP总量呈上升趋势。

Based on the 0. 1^o× 0.1^o resolution map of vegetation type, soil texture and meteorological data, the atmosphere-vegetation interaction model （AVIM2） was used to simulate the response of net primary productivity （NPP） to climate change in the Tibetan Plateau. The results show that the vegetation NPP increased during the past 20 years in the Tibetan Plateau owe to the combination effects of the temperature and precipitation change. The changes of annual mean temperature and annual precipitation were positively correlated with the change of NPP during the last 20 years. The influence of precipitation change to forests and grassland NPP were higher than that of temperature, whereas the effects of precipitation to shrubs were lower than that of temperature. The total NPP for shrub and forest increased 1.14% and 0. 88% per year, individually. There increasing trend reach the statistically significant level. The increasing trend for grassland NPP was gentler than that for forests and shrubs. On the wholestudy region, the average annual mean temperature increased 0. 058 ℃ per year, annual precipitation increased and the total vegetation NPP increased during 1981-2000.