【摘要】 近百年来 ,尤其近 2 0年 ,全球气候显著变暖 ,已导致植物物候与生产力在过去 2 0年中发生显著变化。遥感方法是研究植被对全球变暖的响应的一种非常有效的方式 ,利用NOAA/AVHRR数据 ,结合地面气象数据 ,研究近 2 0年来中国东北地区呼伦贝尔草原NDVI与温度、降水变化的相互关系 ,认识呼伦贝尔草原对气候变化的响应特征。研究结果表明 :(1)呼伦贝尔草原地区近 2 0年温度变化明显 ,高于全球平均增温幅度。 (2 )生长季 (4～ 10月 )NDVI有较明显上升 ,线性拟合分析表明 ,所选 4个区域近 2 0年生长季NDVI平均值上升了 2 .2 %。 (3)NDVI的增加主要在 1988年前后 ,在草原东部后一阶段 (1988～ 1999)比前一阶段 (1982～ 1987)NDVI平均值增加了 7.8%。(4 )呼伦贝尔草原对全球变暖响应显著。NDVI与气温 ,尤其与春季相关性显著。更多还原

【Abstract】 In the IPCC Third Assessment Report, it is pointed out that the global average temperature has increased 0.6±0.2℃ in the twentieth century, and 1980s and 1990s are the warmest twenty years in the past one hundred years. Global warming during the last century has influenced the environment seriously. The warming trend in the past 20 years has been making the phenology and productivity of vegetation changes remarkably. Northeast China is one of the most sensitive areas in response to the global warming in China and the annual temperature in this area has increase more than one degree in the past twenty years. Forest, grassland and farmland are three major types of vegetation in Northeast China. The vegetation in Hulun Buir Steppe, which belongs to the semiarid land lying in the northwest of Northeast China, are the representative of the grassland in the temperate zone responding to the global warming in the past twenty years. Based on NOAA/AVHRR data, combined with the observed meteorological data of Hailar in the area, a case study on the response of the grassland in the Hulun Buir Steppe of Northeast China to global warming in the past 20 years is made in this paper. The results show that: (1) The temperature in Hailar increases 0.10℃ per year, which shows that the temperature in the Hulun Buir Steppe has increased remarkably than that in the global during the last 18 years; (2) The four selected areas averaged NDVI in growing season (from April to October) has obviously increased by 2.2% in the past 18 years; (3) The obvious increase of NDVI happened around 1988, when the mean NDVI during 1988～1999 is 7.8% more than that during 1982～1987 in the east part of the Hulun Buir Steppe, which means that the carrying capacity of the grassland has increased. (4) Response of the Hulun Buir Steppe to the globe warming is remarkable. The NDVI and the temperature, especially the temperature in spring, have sensitive positive correlativity; (5) From April to October, because of the precipitation, the influence of the temperature to the cumulative NDVI decreases little by little from east to the west. In the Filifoliu msibiricumgrassland of the east, the influence of the temperature in April is remarkable; while in the Leymus chinenssgrassland (Stipa baicalensisincluded) and the Stipa grandisand S.kryloviigrassland of the west, the influence of the precipitation in July is remarkable.更多还原