摘要
在地理信息系统技术支持下，利用SPOTNDVI时间序列数据集分析了1999—2008年珠三角地区地表植被覆盖变化，并利用地统计学方法计算了Moran’s I系数与半变异子函数，研究结果表明：珠三角地区植被NDV1年均值呈现出了“升-降-升”的波动增长过程，近10年来NDV1年均值共计增长了9．2％，珠三角核心地带的城市连绵区植被地表由于强烈的人为干扰退化较明显，而外围的山地植被NDVI正在发生着明显的正向变化，形成了珠三角地区的重要生态屏障。NDVI在全局范围内存在负的空间自相关，但具有各向异性的结构性分化，135°（西北-东南）方向上NDVI表现出明显的正相关；随机因子所导致的空间变异仅占系统总变异的19．7％，结构性因子在珠三角地表植被空间异质性中占据绝对控制地位。研究结果同时也表明快速城市化区域地表植被变化对生态环境的影响不可忽视。
Vegetation coverage Spatio - temporal changes in Pearl River Delta （PRD） were analyzed based on SPOT - VGT NDVI time series data for 10 years from 1999 to 2008, and the Moran＇ s I index and semi - variogram function were calculated by using GIS and geostatistic method. Research results showed that the annual average NDVI increased by 9.2% with a fluctuation of up - down - up in the past 10 years, the vegetation coverage in the metropolitan interlocking region of PRD degenerated significantly disturbed by urbanization processes and man - made factors to a certain extent, while the NDVI in the outer portion increased significantly and these areas are be- coming an ecological barrier of PRD. The spatial distribution pattern of NDVI shows negative autocorrelation on a global scale, but there were anisotropic structural difference and a higher positive spatial correlation in 135 o （NW - SE） direction. The NDVI spatial distribution was mainly controlled by structural factors, 80.3 % of the total spa- tial variation was influenced by structural and 19.7% by random factors. The study indicates that the impacts of Vegetation coverage changes on the eco - environment can not be neglected or ignored in the rapidly urbanizing area in China.
出处
《嘉应学院学报》
2010年第2期82-87,共6页
Journal of Jiaying University
关键词
珠三角
植被覆盖
SPOT
NDVI
空间异质性
vegetation coverage
SPOT -VGT NDVI
Pearl River Delta （PRD）
spatial heterogeneity
