中国西南地区2009～2015年植被覆盖度变化及其与降雨的关系

Vegetation cover change and its relationship with painfall in Southwest of China during 2009～2015

运用均值法、变异系数法(CV)和相关分析法,从地貌、植被类型、坡度,分析中国西南五省2009~2015年林草植被盖度变化及其与降雨的关系。结果表明:1)2009~2015年,林草植被覆盖度从0.87下降至0.78,植被退化明显;2)长江中游低山平原林草植被变化最剧烈,与降雨变化的相关性最强;横断山高山峡谷林草植被状况最稳定,与降雨变化的相关性最弱;3)中亚热带常绿阔叶林的林草植被变化最剧烈,与降雨变化的相关性最强;草甸与针叶林地带的林草植被状况最稳定,与降雨变化的相关性最弱;>6~15°区域的林草植被变化最为剧烈,与降雨变化的相关性最强;4)>25~90°坡度区域的林草植被状况最稳定,与降雨变化的相关性最弱。降雨对西南五省(区)的植被影响存在明显的空间差异性。

Based on landform condition,vegetation type,and slope gradient,from macroscopic to microcosmic,the mean value,variation coefficient（CV） and methods are used to analysize the physical geographical features of vegetation coverage change and its relationship with rainfall in the five provinces in Southwest of China during 2009~2015.The results show that：1） During 2009~2015,the vegetation coverage decreased from 0.87 to 0.78,vegetation degradated obviously;2） As for the landform conditions,vegetation coverage changed dramatically at low mountain-plain regionat the middle reaches of the Yangtze River,the influence of rainfall is most obvious;It also showed stable in alpine and gorge region at Hengduan Mountains,where was less affected by rainfall;3） As for the vegetation types,vegetation coverage changed dramatically in the mid-subtropical evergreen broad-leaved forest regionand,which are most affected by rainfall.It also showed stable in the meadow and coniferous forest regions,and is less affected by rainfall;4） As for the slope gradients,vegetation coverage changed dramatically in the region of 6~15°,which are most affected by rainfall.And showed stable in the region of 25~90°.which are less affected by rainfall.In conclusion,there is obvious spatial difference in the influence between rainfall and Vegetation Cover Change in the five provinces of Southwest china.