基于Landsat时序数据的长株潭城市群核心区森林扰动监测  

Forest disturbance monitoring in the core area of Changzhutan urban agglomeration based on Landsat time series data

作　　者：谢天飞 蒋馥根 王霞 龙依 孙华[1,2,3] XIE Tianfei;JIANG Fugen;WANG Xia;LONG Yi;SUN Hua(Research Center of Forestry Remote Sensing&Information Engineering,Central South University of Forestry&Technology,Changsha 410004,Hunan,China;Hunan Provincial Key Laboratory of Forestry RemoteSensing Based Big Data&Ecological Security,Central South University of Forestry&Technology,Changsha 410004,Hunan,China;Key Laboratory of National Forestry and Grassland Administration on Forest ResourcesManagement and Monitoring in Southern China,Central South University of Forestry&Technology,Changsha 410004,Hunan,China;Forestry and Grassland Survey&Planning Institute of Hebei Province,Shijiazhuang 050011,Hebei,China)

机构地区：[1]中南林业科技大学林业遥感信息工程研究中心,湖南长沙410004 [2]中南林业科技大学林业遥感大数据与生态安全湖南省重点实验室,湖南长沙410004 [3]中南林业科技大学南方森林资源经营与监测国家林业与草原局重点实验室,湖南长沙410004 [4]河北省林业和草原调查规划设计院,河北石家庄050011

出　　处：《中南林业科技大学学报》2024年第8期94-103,共10页Journal of Central South University of Forestry & Technology

基　　金：国家自然科学基金项目(31971578);湖南省科技创新计划项目(2023RC1065);湖南省自然科学基金项目(2022JJ30078)。

摘　　要：【目的】为了快速准确地监测城市群核心区内的森林扰动,研究利用Landsat时间序列数据在谷歌地球引擎(Google Earth Engine,GEE)平台运用LandTrendr算法进行森林扰动监测研究。【方法】基于2000—2020年植被生长季的Landsat时序数据,分别在归一化植被指数(Normalized Difference Vegetation Index,NDVI)、归一化燃烧率指数(Normalized Burn Ratio,NBR)、缨帽变换角(Tasseled Cap Arctangent,TCA)三种指数作为阈值限制下,采用LandTrendr算法对时间序列轨迹进行处理,以获取长株潭核心区森林扰动的发生区域及规模大小的信息。运用森林资源连续清查数据和Google Earth历史影像分别对3种不同指数的森林扰动监测结果进行精度评估和验证,并利用研究区内土地利用数据中的森林覆盖数据对扰动信息进行分析。【结果】2000—2020年长株潭核心区森林扰动总面积为264.35 km^(2),平均每年的扰动面积为13.22 km^(2),其中2002年扰动最少,为1.91 km^(2),扰动面积最大的为2011年,为25.52 km^(2)。运用森林资源连续清查数据对三种指数阈值限制下的森林扰动信息结果验证的精度分别为90.91%、81.72%和65.08%;在谷歌地球历史影像中随机布点下精度分别为86.00%、77.88%和78.36%。2009年和2011—2013年间森林扰动较为严重。对全国范围内的土地利用数据进行处理分析可知,森林面积在20年间随时间增长而缓慢减少,所占总面积的百分比由原来的27.10%减少到22.00%。【结论】NBR是最适合长株潭核心区的森林扰动指数,森林扰动检测结果与实地调查和谷歌地球历史影像目视解译的结果一致。森林扰动斑块的分布边界可被完整提取,扰动面积大小变化趋势与全国区域内土地利用数据森林面积变化趋势相同,主要由城市化进程、森林火灾和人工砍伐引起。2000—2020年研究区森林扰动面积呈现波动式缓慢增加的趋势,其中2001年、2011年和2013年存在扰【Objective】In order to quickly and accurately monitor the forest disturbance in the core area of the urban agglomeration,this study uses Landsat time series data to monitor the forest disturbance in Google Earth Engine(GEE)using LandTrend algorithm.【Method】Based on the Landsat time series data of the vegetation growth season from 2000 to 2020,under the threshold restrictions of NDVI,NBR,and TCA indices,the LandTrender algorithm was used to process the time series trajectory to obtain information on the occurrence area and scale of forest disturbance in the core area of Changzhutan urban agglomeration.Combining continuous forest resource inventory data and Google Earth historical images,the accuracy evaluation and validation of forest disturbance monitoring results based on different indices were conducted,and the disturbance information was analyzed using forest cover data from land use data in the study area.【Result】From 2000 to 2020,the total disturbed area of the forest in the core area of Changzhutan urban agglomeration was 264.35 km^(2),with an average annual disturbed area of 13.22 km^(2).Among them,the least disturbed area was 1.91 km^(2)in 2002,and the largest disturbed area was 25.52 km^(2)in 2011.The accuracy of forest disturbance information results under the three index thresholds of NBR,NDVI,and TCA under continuous forest resource inventory data was 90.91%,81.72%,and 65.08%,respectively;In Google Earth’s historical images,the accuracy of random point distribution was 86.00%,77.88%and 78.36%,respectively.There were significant disturbances in the forest from 2009 to 2011 to 2013.After processing and analyzing land use data nationwide,it could be seen that the forest area gradually decreased over time over the past 20 years,with the percentage of the total area decreasing from 27.10%to around 22.00%.【Conclusion】NBR is the most suitable forest disturbance index for the core area of Changzhutan urban agglomeration.The results of forest disturbance detection are consistent with the resu

关 键 词：森林扰动 LandTrendr 归一化燃烧率指数 城市森林 长株潭城市群核心区 

分 类 号：S794.4[农业科学—林木遗传育种] TP79[农业科学—林学]