基于MODIS-NDVI数据广西植被覆盖变化特征分析

Analysis of Characteristics of Vegetation Cover Change in Guangxi Province Based on MODIS-NDVI

利用月合成MODIS-NDVI时间序列数据、气象数据、DEM等数据,分析研究了2001-2010年广西省10年间植被覆盖变化的特征。结果表明,广西植被覆盖率较高且总体呈上升趋势,从区域角度分析,桂南地区增加趋势最显著,其次是桂中地区;从海拔梯度角度分析,海拔200 m以下的区域植被覆盖增加趋势最显著,但此区域的植被覆盖率较低,NDVI最高分布在海拔400-800 m的区域。植被覆盖变化受气温、降水及人类活动影响较大,植被覆盖梯度变化除受这些因素影响外,也与植被垂直地理分布特征相关。

Base on the monthly time series MODIS-NDVI, meteorologic and digital elevation model（DEM） data from 2001 to2010, analysed the change characters of surface vegetation coverage of Guangxi Province during this 10 years. The results showed that the vegetation coverage of Guangxi was at a high level with a growing tendency. The growing tendency was the most remarkable in southern Guangxi and followed by the middle Guangxi area. Vegetation coverage change with the vary classified elevation levels. The 200 m below level hold the most obvious growing trend while its NDVI was lower. NDVI was highest at altitude of400-800 m range. The temperature, rainfall and human activities could influence the vegetation coverage. Beside all these three factors,the vegetation coverage was also associated with the vertical characteristics of geographical distribution of vegetation.