哀牢山东、西两侧植被NDVI指数和植被类型与主要环境因子的相关性分析

Correlation analysis of vegetation NDVI and type of vegetation with main environmental factors on eastern and western sides of Ailao Mountain

以哀牢山南段为研究区域,利用遥感植被信息、气候数据以及DEM基础资料,对哀牢山东、西两侧植被的NDVI指数和不同植被类型与主要环境因子的相关性进行分析。研究结果表明,哀牢山东、西两侧山地植被的NDVI指数与海拔的相关性最大,与气温、降水量和太阳总辐射量也有一定的相关性,与坡度和坡向的相关性最小。哀牢山东、西两侧的植被NDVI指数都与年均最低温和年均最高温呈负相关,且东侧区域的相关性大于西侧,表明极值气温对东侧区域的植被影响更大。在哀牢山东、西两侧研究区内共有9种植被类型,以稀树灌木草丛为主要植被类型,分别占各自区域面积的40.59%和35.82%;西侧森林植被中常绿部分所占比重高于东侧。相对于东侧区域,哀牢山西侧区域的海拔偏高、气温偏低、降水量较多、太阳总辐射量较大、植被覆盖度较高。总之,基于地形对水热因子空间再分配的影响作用,哀牢山山脉两侧的气候和植被特征具有较大差异。

The correlations of NDVI and type of vegetation with main environmental factors on eastern and western sides of southern Ailao Mountain were analyzed by means of remote sensing information, climatic data and DEM basic data. The results show that on both sides, the correlation between NDVI and altitude is the highest, there are also some certain correlations between NDVI with air temperature, precipitation or total solar radiation, and the correlations of NDVI with slope and aspect are the lowest. NDVI has a negative correlation with annual mean minimum/maximum temperature on both sides of the mountain, and the coefficient on the eastern side is higher than that on the western side, indicating that extreme temperature has a bigger influence on vegetation on the eastern side. There are nine types of vegetation in the study areas on eastern and western sides of the mountain, mainly savanna which covers 40.59% and 35.82% of the two areas. Evergreen component of vegetation on the western side accounts for more percentage than that on the eastern side. The western side of Ailao Mountain has higher altitude, lower air temperature, more precipitation and more total solar radiation than eastern side, which make the higher vegetation coverage on the western side. It is suggested that because of the effect of tepography on redistribution of water and heat, there are different characteristics in climate and vegetation on both sides of Ailao Mountain.