摘要
农田防护林林带保存率反映了林带结构的完整性,对林带防护效应的发挥有重要影响。传统的基于野外调查获取的林带保存率数据准确,但无法满足快速、大面积监测的需求。利用遥感手段获取农田防护林保存率信息,有利于农田防护林结构和功能的相关研究,并可为农田防护林精准经营和管理提供依据。本文基于我国吉林一号高分辨率多光谱遥感影像,利用遥感信息提取方法获取农田防护林矢量和植被覆盖度数据,并将每条农田防护林林带视为二维矩阵,有序提取林带走向和林带宽度方向的植被覆盖度值,通过分析林带波形特征确定林带边界,并通过阈值方法提取边界内部林带像元,完成林带保存率的遥感识别,最后按林带走向和不同保存率范围共获取160个验证点的参考数据对遥感识别结果进行验证。结果显示:(1)林带保存率遥感识别结果与参考数据的相关性较强(R^(2)=0.936),平均绝对误差为5.4%,总体精度较高;(2)林带保存率在不同林带走向的识别效果均较好,相对而言,南北走向的相关性相对低,其可能是受到林带阴影的影响;(3)林带保存率遥感识别的绝对误差随保存率的增加呈现出先增加后减小的趋势,即对高保存率林带(>80%)和低保存率林带(<20%)的绝对误差最小,监测精度最高,在保存率处于中间状态,尤其是在50%~60%区间内的绝对误差最大,其可能与该部分林带较为破碎、林隙小而多有关。基于高分辨率多光谱卫星影像能够较为准确地识别农田防护林林带保存率,该方法提高了农田防护林结构的遥感监测能力,并可为农田防护林结构与功能的准确监测和评价提供技术支撑。
The preservation rate of farmland shelterbelts reflects the integrity of the shelterbelt structure,determining the protection effectiveness of shelterbelts.Although traditional field measured data of shelterbelt preservation rate are accurate,this method could not meet the needs for rapid and largescale monitoring.It is of great importance to obtain the information of shelterbelt preservation rate by remote sensing,which could be significantly helpful for the structural and functional research and precise management of farmland shelterbelts.In this study,using the shelterbelt vector line and vegetation fraction data extracted from Jilin1 highresolution multispectral remote sensing images,a set of ordered points were extracted along the belt orientation and belt width directions by considering each shelterbelt as a twodimensional matrix.The shelterbelt boundary was recognized by analyzing the waveform characteristics,and the shelterbelt pixels were determined by the threshold value.Finally,the preservation rate of farmland shelterbelts was identified from the remote sensing image,which were further verified by the reference data(sample number was 160).There were three main findings.(1)The remote sensing identification results and the reference data was significantly correlated(R^(2)=0.936),and the average absolute error was 5.4%,indicating a high overall accuracy.(2)The identification results in different belt directions were highly correlated with the reference data.The correlation in northsouth direction was relatively low,which may be affected by belt shadows.(3)The absolute error of identification results increased first and then decreased with the increases of preservation rate.The absolute error was the smallest in high preservation rate(>80%)and low preservation rate(<20%),and the largest in the middle state,especially in the interval of 50%-60%,because these shelterbelts were more fragmented,with small and numerous gaps.In summary,the preservation rate of farmland shelterbelt can be accurately identified based on highresolution multispectral satellite images.This method promotes the ability of remote sensing monitoring for shelterbelt structure,which could provide technical support for accurate monitoring the structure and function of farmland shelterbelts.
作者
邓荣鑫
幸泽峰
李颖
张兴
杨高
李世明
贾孟豪
DENG Rongxin;XING Zefeng;LI Ying;ZHANG Xing;YANG Gao;LI Shiming;JIA Menghao(College of Surveying and Geo-informatics,North China University of Water Resources and Electric Power,Zhengzhou 450046,China;Academy of Agricultural Planning and Engineering,Ministry of Agriculture and Rural Affairs,Beijing 100125,China;Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2024年第9期2658-2666,共9页
Chinese Journal of Ecology
基金
国家自然科学基金面上项目(31971723)
河南省高等学校青年骨干教师培养计划项目(2020GGJS101)资助。
关键词
农田防护林
林带结构
遥感
农林系统
farmland shelterbelt
belt structure
remote sensing
agroforestry system