基于GEE的鄱阳湖湿地植被长期变化特征及其对水文情势的响应北大核心CSCD

针对鄱阳湖湿地植被长期变化的科学问题,本文基于谷歌地球引擎(GEE)遥感大数据平台和CART分类回归树算法提取鄱阳湖2000—2017年涨水期、丰水期、退水期和枯水期的年时序植被分布范围,阐明其时空变化特征;在此基础上,结合水位数据分析湿地植被与水文情势变化之间的响应关系。结果表明,(1)2000—2017年,枯水期、涨水期、丰水期和退水期鄱阳湖湿地植被平均面积分别为846.35、679.03、172.35、508.63 km^(2)。(2)2000—2017年,不同水位期鄱阳湖湿地植被总面积均呈增加趋势,并有向湖心演变的趋势。(3)鄱阳湖植被面积受水位影响显著,水位与植被面积呈负相关,降水异常(如极端降水或严重干旱)是导致植被面积明显偏离平均面积的主导因素。本文结论有助于鄱阳湖湿地生态系统的健康诊断,对鄱阳湖湿地保护和修复政策的制定具有科学参考意义。

Long-term vegetation variation and its response to hydrological regime in Poyang Lake wetland based on GEE

In order to solve the scientific problem of long-term vegetation evolution in Poyang Lake, this paper extracts the annual vegetation distribution range of the rising water period, the high water period, the receding water period and the low water period from 2000 to 2017 based on the Google Earth Engine(GEE) remote sensing big data platform and CART classification regression tree algorithm, and expounds the spatio-time characteristics of the vegetation change. On this basis,It combines with water level data, the response relationship between wetland vegetation and hydrological regime is analyzed. The results show that: ①The average vegetation area of Poyang Lake wetland during the low water period, the rising water period, the high water period and the receding water period from 2000 to 2017 is 846.35km²、679.03km²、172.35km²、508.63km². ②From 2000 to 2017, the total vegetation area of Poyang Lake wetland increased at different water levels and tended to evolve towards the center of the lake. ③The vegetation area of Poyang Lake is significantly affected by water level, and the water level is negatively correlated with the vegetation area. The precipitation anomaly (such as extreme precipitation or severe drought) is the main factor leading to the significant deviation of the average vegetation area. The results of this study have scientific reference significance for the formulation of wetland protection and restoration policies in Poyang Lake.