洞庭湖区土地覆被对长江水位变化的响应分析

为了研究长江水位的变化对洞庭湖区土地覆被的影响，基于洞庭湖区近26 a土地覆被遥感影像的解译成果，分别构建了东洞庭湖区和西+南洞庭湖区水域、泥滩、草洲、芦苇地、裸地和防护林面积与对应时段城陵矶水位之间的回归方程。分析结果显示：东洞庭湖区水域、泥滩、草洲面积和西+南洞庭湖区水域面积与城陵矶水位之间具有极显著的相关关系，而芦苇地、裸地和防护林等面积与城陵矶水位之间的关系并不显著；城陵矶水位变化对东洞庭湖区土地覆被的影响明显高于对西+南洞庭湖区土地覆被的影响。此外，依据所构建回归方程，预测长江上游大型梯级电站运行将导致洞庭湖区呈现泥滩和草洲挤占水域的态势。

Response of land cover in Dongting Lake to water level change of Yangtze River

To research the influence of water level change of Yangtze River on land cover in Dongting Lake, the regression equation between water level at Chenglingji and area of water body, mudflat, grass land, reed shoal, bare land and forest land in Dongting Lake (East, West and South Dongting Lake) was established respectively based on the interpretation result of satellite images in recent 26 years. The analysis results show that the correlation between water level at Chenglingji and the area of water body, mudflat, grass land in East Dongting Lake and the area of water body in West and South Dongting Lake are remarkable, while the correlation of water level and area of reed shoal, bare land and forest land are not; the influence of water level change on land cover type of East Dongting Lake is stronger than that of West and South Dongting Lake. In addition, according to the regression models, the mudflat and grass land will invade the region of water body due to the scheduling of large cascade hydropower stations at the upper reaches of Yangtze River.