20世纪末期黄河源区土地覆盖变化与气候变迁过程研究

The Land Cover Change and the Process of Climate Change in the Source Region of the Yellow River in Late 20th Century

利用NOAA-AVHRR数据,应用BP神经网络图像分类方法,研究了1990~2000年黄河源地区土地覆盖变化的过程,并分析了这11年间黄河源地区的气候变化趋势。在此基础上,通过偏相关模型对土地覆盖变化与气候变化之间的关系进行了分析。结果表明在1990~2000年间,黄河源区域荒漠化土地面积急剧增加,平均植被覆盖度呈持续下降趋势;而区域平均年平均气温、年最高气温都明显升高,年最低气温也有上升趋势,区域平均年降水量则呈波动下降趋势。对两者相关性分析表明,不同土地覆盖类型土地面积与各气象因子之间具有不同的相关关系,气候变化是影响黄河源区土地覆盖变化的一个重要驱动因素。

Based on NOAA data, this paper analyzed the process of land cover change and climate change trend in the source region of Yellow River from 1990 to 2000 by BP neural network. Moreover, the relationship between land cover change and climate change was analyzed by partial correlation model. The results showed that the desertified land area was dramatically increased with a continuous downward trend of average vegetation coverage. Whereas the average annual average temperature and average annual maximum temperatures were obviously increased, and average annual minimum temperature was also on the rise, but the average annual precipitation was presented fluctuant decrease. Correlation analysis showed that the areas of different land covers had different relationships with various meteorological factors. Climate change was an important driven factor for the land cover change in the study area.