地理学报 ›› 2001, Vol. 56 ›› Issue (6): 667-672.doi: 10.11821/xb200106005

• 自然环境变化 • 上一篇    下一篇

黄河流域植被覆盖度动态变化与降水的关系

孙睿1, 刘昌明2, 朱启疆1   

  1. 1. 北京师范大学资源与环境科学系, 北京 100875;
    2. 中国科学院地理科学与资源研究所,北京 100101
  • 收稿日期:2001-09-12 修回日期:2001-10-08 出版日期:2001-11-25 发布日期:2010-09-09
  • 作者简介:孙睿(1970- ),男,博士,副教授。E-mail: sunrui@bnu.edu.cn
  • 基金资助:

    国家重点基础研究规划项目(G1999043601), 国家自然科学基金项目(49871055)

Relationship Between the Fractional Vegetation Cover Change and Rainfall in the Yellow River Basin

SUN Rui1, LIU Chang-ming2, ZHU Qi-jiang1   

  1. Department of Geography, Beijing Normal University, Beijing 100875,China
  • Received:2001-09-12 Revised:2001-10-08 Online:2001-11-25 Published:2010-09-09
  • Supported by:

    National Key Research Program Of Basic Science, No. G1999043601; National Natural Science Foundation of China, No. 49871055

摘要:

利用8 km分辨率Pathfinder NOAA-NDVI数据, 对黄河流域1982~1999年地表植被覆盖的空间分布及时间序列变化进行了分析, 并通过计算不同时段降水量与年最大NDVI之间的相关系数分析了降水对流域植被覆盖的影响。结果发现近20年来黄河流域平均植被覆盖度有增加趋势, 但青藏高原上有所减小; 汛期降水量的多少对地表植被覆盖度的年际变化起主要作用, 其中草原地区影响最显著, 而在森林植被区及部分灌溉农作区, 降水的年际变化对地表覆盖的影响比较小。

关键词: 植被覆盖度, 遥感, 降水, 黄河流域

Abstract:

Vegetation plays an important role in the energy, matter and momentum exchange between land surface and atmosphere and the change of vegetation is mainly caused by climate variation and human activities. Therefore, it is necessary to study the relationship between climate factors and inter-annual change of vegetation, which will help us to understand global change. In order to understand the effects of rainfall on vegetation cover, we selected the Yellow River Basin in China as the study area to assess the inter-annual change of fractional vegetation cover in the Yellow River Basin, and analyzed the relationship between rainfall and fractional vegetation cover using 8 km resolution multi-temporal NOAA AVHRR-NDVI data from 1982 to1999. The data are from NASA Pathfinder AVHRR Land data sets. The spatial distribution and dynamic change of fractional vegetation cover were studied by using yearly maximum NDVI. The results show that in spite of inter-annual fluctuations, there exists an inclining trend of fractional vegetation cover for the whole basin, which is different from the trend of annual rainfall. The inclining trend may be caused by human activities while inter-annual fluctuation may be caused by climate factors. Finally, the correlation coefficients between NDVI and rainfall in different periods (annual rainfall, rainfall in flood and non-flood seasons) were computed for every pixel to assess the effect of rainfall on fractional vegetation cover change. The results show that there is good relationship between NDVI and rainfall in the Yellow River Basin, especially in arid and semi-arid steppe zones, and inter-annual change of fractional vegetation cover is mainly affected by flood season rainfall. However, human activities can reduce the effect, for example, the effect of rainfall on NDVI is small in irrigated cropland.

Key words: fractional vegetation cover, remote sensing, rainfall, the Yellow River Basin