曲麻莱地区植被变化的气候效应分析

ANALYSIS OF CLIMATE EFFECT TO VEGETATION CHANGE IN QUMALAI AREA

利用曲麻莱气象站1982~2013年年平均气温和降水资料、曲麻莱地区牧草观测资料以及植被净初级生产力NPP资料等,分析了曲麻莱地区气候和植被多年变化特征,并对气候条件与植被覆盖的相关关系进行了研究,结果表明:(1)1982~2013年曲麻莱地区年平均气温急剧上升,平均每10a上升0.69℃,降水量总体呈增多趋势,平均每10a增多24.01mm;(2)1982年以来曲麻莱地区牧草生长状况趋好,草层高度、牧草覆盖度和生物量平均每10a分别增加3.44cm、23.34%、467.23kg/hm^2;植被净初级生产力NPP值平均每10a增加18.85。(3)净初级生产力NPP值与年降水量相关关系较好,但与气温和日照时数相关性较差;(4)当年降水量分别增加10%、30%和50%时,净初级生产力NPP值分别增加8.96%、26.87%和44.79%。植被对气候变化的响应反映在高度、产量和综合指标NPP等要素上,近35a年来,曲麻莱地区的气温显著上升,降水量增加,日照时数基本不变,气候条件有利于NPP值的增加,草地生态状况趋于良性方向发展。

Using the annual mean temperature and precipitation data during 1982 to 2013,the observation data of Qumalai herbage and the NPP data（ net primary productivity）,the characteristics of climate and vegetation in Qumalai were analyzed,and the relationship between climate conditions and vegetation coverage was studied,the result showed：（ 1） From 1982 to 2013,the annual average temperature in Qumalai increased sharply by the rate of 0. 69℃/10 a,the total precipitation showed an increasing trend,with a rate of 24. 01 mm/10 a;（ 2） Since1982,the growth of herbage in Qumalai area had been getting better,the height of grass layer,the coverage of herbage,the biomass and NPP increased by 3.44 cm/10 a,23.34%/10 a,467.23 kg/hm^2/10 a and 18.85/10 a respectively.（ 3） There was a better relationship between NPP and annual precipitation,but poor relationship between NPP and temperature and sunlight.（ 4） When the annual precipitation increased by 10%,30% and50%,the NPP increased by 8. 96%,26. 87% and 44. 79%,respectively. The response of vegetation to climate change reflected in the factors such as height,yield and comprehensive index. In the past 35 a years,the temperature of Qumalai area had risen significantly,the precipitation increased,the sunshine hours were basically unchanged,such climate conditions were beneficial to the increasing of NPP,and the ecological condition of the grassland tended to develop in a benign direction.