呼伦贝尔草原、湿地和森林植被对气候变化的响应

The Response of Steppe,Wetland and Forest Vegetation to Climate Change in Hulun Buir

气候变化会影响区域生态系统的结构和功能。植被覆盖状况是研究不同类型植被对气候变化响应的重要指标。采用遥感与GIS技术,对1981~2012年呼伦贝尔草原不同植被类型的植被变化特征及其与气候变化因子的关系进行对比分析,以揭示植被覆盖状况对气候变化的响应规律。得出以下结论:(1)该地区的气候在1998年前后发生显著变化,在1981~1999年植被年均NDVI(Normalized Difference Vegetation Index)的波动较平缓,在2000~2012年植被年均NDVI的波动较大。(2)32年间该区森林和湿地的年均NDVI增加,且年际波动较稳定,NDVI与温度呈正相关,而与降水呈负相关;但草原的年均NDVI减少,年际波动较强烈,并与降水量呈极显著正相关(P<0.01),但与温度呈极显著负相关(P<0.01)。研究结果表明,草原比森林和湿地对气候变化的响应更为强烈,并受降水的影响较大,加之过度放牧的影响,其对气候变化的适应性较弱。

Climate change will affect the structure and function of regional ecosystems.Vegetation cover is an important index to study the response of different types of vegetation to climate change.We used remote sensing and GIS technology to investigate the characteristics of vegetation change of different vegetation types in Hulun Buir Grassland in the past 1981~2012 years,and analyze and the relationship between these characteristics andwith climate change factors of different vegetation types in Hulun Buir Grassland in the past 1981~2012 years,in order to reveal the response law of vegetation cover to climate change.We conclude that:(1)The climate in of this the region changed significantly before and afteraround 1998.The average annual average NDVI(Normalized Difference Vegetation Index)of vegetation fluctuated slowly between from 1981 toand 1999,and the average annual average NDVI of vegetation fluctuated significantly changed a lot between from 2000 and to 2012.(2)The average annual average NDVI of forests and wetlands in the region increased during the 32 years,and the interannual fluctuations were relatively stable.The NDVI was positively correlated with the temperature,and it waswhile negatively correlated with the precipitation.The average annual average NDVI of the steppe decreased,and the interannual fluctuations was stronger,and there was an extremely significant positive correlation with the precipitation(P <0.01),but an extremely significant negative correlation with temperature(P <0.01).The results showed that steppe has a stronger responsive to climate change than forest and wetland,and is greatly influenced by precipitation.In addition to the influence of overgrazing,it has a weak adaptability to climate change.