摘要
大通河流域地处甘青两省交界处,是湟水流域最大的子流域,同时也是祁连山地的重要组成部分,流域中下游河谷狭窄纵深、山体陡峭,水资源与森林资源丰富。森林资源对该流域及其周边地区涵养水源、调节气候变化及水土保持等方面起着至关重要的作用。本研究基于GEE(Google Earth Engine)云平台,获取了研究区1987—2023年Landsat卫星长时序影像,逐年合成生长季(6—9月)的无云影像。研究采用改进的VCT(Vegetation Change Tracker)算法结合森林样本自动提取方法,对流域近37年森林时空变化及其干扰进行了监测研究。结果表明:森林主要集中分布在流域中下游的河谷两岸及其山体两侧;改进的VCT检测算法在森林、非森林与森林干扰3种类别的识别中,总体精度达到90.63%,Kappa系数达0.85,证明该方法在长时间序列森林变化监测中的有效性和可靠性。1989—2000年森林扰动较为集中,而2000—2023年扰动相对较少。研究结果可为该流域森林资源管理与生态保护提供数据支撑。改进的VCT检测算法结合GEE平台被证明是一种有效的森林干扰和动态变化监测手段。
The Datong River Basin is located at the border of Gansu and Qinghai provinces.It is the largest sub-basin of the Huangshui River Basin and an important component of the Qilian Mountains.The middle and lower reaches of the basin feature narrow,deep valleys and steep mountains,with abundant water and forest resources.Forest resources play a crucial role in water conservation,climate regulation,and soil and water preservation for this basin and its surrounding areas.Based on the Google Earth Engine(GEE)cloud platform,long-term time-series Landsat satellite imagery from 1987 to 2023 for the study area was obtained,and cloud-free images during the growing season(June to September)were composited annually.Using an improved VCT(Vegetation Change Tracker)algorithm combined with an automated forest sample extraction method,this study monitored the spatiotemporal changes and disturbances of forests in the basin over the past 37 years.The research indicates that forests are primarily distributed along the river valleys and mountain slopes in the middle and lower reaches of the basin.The improved VCT detection algorithm achieved an overall accuracy of 90.63%and a Kappa coefficient of 0.85 in identifying three categories:forest,non-forest,and forest disturbance,demonstrating the method's effectiveness and reliability in monitoring long-term forest change.Forest disturbances were more concentrated between 1989 and 2000,while they were relatively fewer from 2000 to 2023.The findings provide data support for forest resource management and ecological protection in the basin.The improved VCT detection algorithm combined with the GEE platform proves to be an effective tool for monitoring forest disturbances and dynamic changes.
作者
黄燕君
高小红
Huang Yanjun;Gao Xiaohong(MOE Key Laboratory of Tibetan Plateau Land Surface Processes and Ecology,Qinghai Normal University,Xining 810008,China;School of Geographical Sciences,Qinghai Province Key Laboratory of Physical Geography and Environmental Process,Qinghai Normal University,Xining 810008,China)
出处
《遥感技术与应用》
北大核心
2026年第1期278-290,共13页
Remote Sensing Technology and Application
基金
青海省科技厅自然科学基金项目(2021-ZJ-913)。
