青海湖流域植被覆盖时空变化特征及驱动力分析

Spatio-temporal variation characteristics ofvegetation coverage and its drivingforces in Qinghai Lake Basin

摘要:

【目的】 探索青海湖流域植被动态变化格局及其对气候变化和人类活动的响应。【方法】 采用趋势分析、多元回归残差分析、偏相关分析等方法，以MOD13Q1 遥感数据和气象数据为基础，分析2001-2019 年流域植被覆盖时空变化特征及其驱动力。【结果】（ 1）2001-2019年青海湖流域植被覆盖度（FVC）增长率为2. 1%/10 a，呈显著波动上升趋势（P＜0. 05），FVC 改善面积约为1. 21×10⁴ km²，占总面积的48. 77%；（2）气候变化和人类活动对植被覆盖变化的贡献率分别为57. 83% 和41. 52%；（3）降水和温度与FVC 变化呈显著正相关的面积占比分别为7. 93% 和4. 15%。【结论】 近19 a 年青海湖流域FVC 整体改善显著，显著改善区域主要分布于流域西部和青海湖北岸区域；气候变化是流域FVC变化的主导因素，但人类活动对局地FVC 变化具有显著的抑制作用；降水对流域FVC 变化的影响力更高，局地FVC 变化对温度响应更强烈。

Abstract:

【Objective】 The study was carried out to explore the dynamic change pattern of vegetation in QinghaiLake Basin and its response to climate change and human activities.【Method】 Based on MOD13Q1 remote sensingdata and meteorological data， this paper analyzed the spatial and temporal variation characteristics and driving forces of vegetation coverage in the basin from 2001 to 2019 by means of trend analysis， multiple regression residual analy-sis and partial correlation analysis.【Result】 The results showed that：（1） The growth rate of fractional vegetationcover （FVC） in Qinghai Lake Basin from 2001 to 2019 was 2. 1%/10 a，showing a significant upward trend （P＜0. 05）. The improved area of FVC was about 1. 21×10⁴ km²，accounting for 48. 77% of the total area.（2） The con-tribution rates of climate change and human activities to vegetation cover change were 57. 83% and 41. 52%，respec-tively.（3） The area ratios of precipitation and temperature significantly positively correlated with FVC changes were7. 93% and 4. 15%，respectively.【Conclusion】 The analysis shows that the overall improvement of FVC in the Qing-hai Lake Basin in the past 19 a is significant， and the significant improvement areas are mainly distributed in the west-ern part of the basin and the northern bank of Qinghai Lake. Climate change is the dominant factor of FVC change inthe basin，but human activities have a significant inhibitory effect on the local area. Precipitation has a higher influenceon FVC changes in the basin，and local FVC changes respond more strongly to temperature.