1982-2009 年珠穆朗玛峰自然保护区植被指数变化

植被指数是指示植被变化的重要指标, 本研究基于1982-2009 年珠穆朗玛峰自然保护区(简称珠峰地区)植被指数(NDVI)时间序列数据、土地覆被和野外调查等数据, 采用时序变化趋势和空间分析法, 对珠穆朗玛峰地区植被的时空变化过程及保护区成效进行了定量分析。研究表明:①珠峰地区NDVI分布的总特征是南部和北部高, 中部低。②1982-2009 年珠峰地区NDVI年际变化趋势和空间异质性十分明显:1982-1997 年, 珠峰地区NDVI总体上呈显著上升趋势, 北部地区增幅较大;1998-2009 年, NDVI总体下降(56.96%的NDVI呈下降趋势), 其中, 珠峰地区中部和北部的NDVI下降最为明显, 而南部核心保护区森林和灌丛的NDVI则呈显著上升趋势, 且变化幅度较大。③长时间序列植被指数变化的过程和空间差异性推断:1998 年以来, 天然林保护等生态工程促使珠峰地区保护效果更加明显。

NDVI Change Analysis in the Mount Qomolangma (Everest) National Nature Preserve during 1982-2009

NDVI is a good indicator for monitoring the vegetation change.NDVI time series data during 1982-2009,land cover data and field survey have been used to monitor the temporal-spatial change for vegetation and to analyze the effectiveness of protected area quantitatively in the vicinity of Mount Qomolangma by using the time series change trend detection and spatial analysis methods.This study reveals that the overall distribution of NDVI is with a higher value at the southern and northern and a lower value at the middle area in the vicinity of Mount Qomolangma.Inter-annual change trend and spatial heterogeneity of NDVI during 1982-2009 are completely obvious in the study area,with a distinct overall increase of NDVI during 1982-1997,and especially bigger increase in the northern area,and with an overall decrease during 1998-2009(descending of 56.96%),including the distinct decrease in the central and northern parts of the study area and a partial increase of the NDVI of forests and scrublands in the core area of southern protected area.The long-term time series NDVI change trend and spatial difference concludes the ecological conservation engineering such as natural forest protection has made the effectiveness of protected area more outstanding since 1998.