【摘要】 植被作为自然生态系统的重要要素和环境组分,能够反应自然地域综合体在全球气候变化与人类活动影响下的时空特征变化,因此在探讨地表过程及全球变化研究中有着举足轻重的地位。以MODIS-NDVI时间序列数据和SRTM数据为基础,利用像元二分模型对干旱区内陆河——克里雅河流域2002-2013年的植被覆盖度进行了估算,分析了该流域植被覆盖度时空变化特征及其与地形、气象因子的相互关系。结果表明:克里雅河流域植被覆盖存在着明显的垂直地带性空间差异,其海拔3 000～3 500 m范围的丘陵带平均植被覆盖度最大;过去12 a来该流域植被覆盖度整体上呈减少趋势,其中上游高山带、中游冲积扇平原带和下游沙漠带植被覆盖逐渐退化,而低山丘陵带植被覆盖变化有上升趋势并逐渐改善;总体上,流域植被覆盖与气温变化呈负相关关系,而与降水变化表现出正相关。更多还原

【Abstract】 As an important element of natural ecosystem and environment component,vegetation can reflect the spatial and temporal variation characteristics of comprehensive geographical systems under global climatic change and human disturbance,therefore it has a pivotal role in surface process and global change research. In this paper,vegetation coverage of Keriya River Basin from 2002 to 2013 is estimated based on MODIS-NDVI time-series data and SRTM data by using dimidiate pixel model,then the correlation between spatial-temporal changes of vegetation coverage and climatic factors is analyzed. Results show that: vegetation coverage of Keriya River Basin has vertical zonal difference. On low hilly zone with the altitude of 3 000 ～ 3 500 m,the mean vegetation coverage reaches maximum value. Over the past 12 years,vegetation coverage in the basin as a whole has shown a decreasing trend,vegetation coverage in the upstream high mountain area,midstream alluvium and diluvium plain area and downstream desert vegetation decrease gradually. Vegetation coverage in the low hilly zone is on the rise and improved. Generally,in Keriya River Basin,vegetation coverage is negatively correlated with temperature,positively correlated with precipitation.更多还原