GEDI L2A不同算法对地面高程和森林冠层高度精度的影响分析  

Analysis of the influence of different algorithms of GEDI L2A on the accuracy of ground elevation and forest canopy height

作　　者：刘丽娟[1] 王成[1,2] 聂胜 朱笑笑 习晓环 王金亮 LIU Lijuan;WANG Cheng;NIE Sheng;ZHU Xiaoxiao;XI Xiaohuan;WANG Jinliang(Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan, Center for Geospatial Information Engineering and Technology of Yunnan Province, Faculty of Geography, Yunnan Normal University,Kunming 650500, China;CAS Key Laboratory of Digital Earth, Aerospace Information Research Institute, Chinese Academy of Sciences,Beijing 100094, China)

机构地区：[1]云南师范大学地理学部云南省高校资源与环境遥感重点实验室云南省地理空间信息技术工程技术研究中心,昆明650500 [2]中国科学院空天信息创新研究院中国科学院数字地球重点实验室,北京100094

出　　处：《中国科学院大学学报（中英文）》2022年第4期502-511,共10页Journal of University of Chinese Academy of Sciences

基　　金：国家自然科学基金面上项目(42071405);中国科学院青年创新促进会(2019130);国家重点研发计划政府间国际科技创新合作重点专项(2018YFE0184300)资助。

摘　　要：全球生态系统动力学调查(global ecosystem dynamics investigation,GEDI)雷达是美国2018年12月发射的全波形激光雷达系统,可以为全球地面高程及森林冠层高度提供数据支持。为适应不同地表环境,GEDI L2A产品提供了6种不同算法来估算地面高程及森林冠层高度,这些算法的选择会影响地表参数的提取精度。以机载LiDAR得到的数字地形模型和冠层高度模型为参考数据,评估第2版GEDI L2A数据在不同植被覆盖度下不同算法的适应性以及对地面高程和森林冠层高度精度的影响。结果表明,在覆盖度小于0.2时,算法4的结果最优,在覆盖度大于等于0.8时算法2的结果最优,其余覆盖度下算法1的结果最优。将本文根据植被覆盖度选择的最优算法与GEDI L2A默认最优算法进行比较,整体看来本文的结果优于GEDI L2A默认最优算法的结果,特别是在覆盖度小于0.8,坡度大于等于10°时,本文选择的最优算法能有效提高GEDI L2A产品对地面高程和森林冠层高度估算的精度。The global ecosystem dynamics investigation(GEDI)is a full-waveform LiDAR system launched by United States in December 2018,which can provide data support for global ground elevation and forest canopy height.In order to adapt to different surface environments,GEDI L2A products provide 6 different algorithms to estimate ground elevation and forest canopy height.The choice of these algorithms will affect the extraction accuracy of surface parameters.In this paper,the digital terrain model and canopy height model obtained by airborne laser scanning data are used as reference data to evaluate the adaptability of different algorithms of the second version of GEDI L2A data under different vegetation coverage values and the impact on the accuracy of ground elevation and forest canopy height.The results show that when the vegetation coverage is less than 0.2,the result of algorithm 4 is the best,when the coverage is greater than or equal to 0.8,the result of algorithm 2 is the best,and the result of algorithm 1 is the best under the remaining coverage values.Comparing the optimal algorithm selected in this paper according to the vegetation coverage with the GEDI L2A default optimal algorithm,the results of this paper are generally better than those of the GEDI L2A default optimal algorithm,especially when the coverage value is less than 0.8 and the slope is greater than or equal to 10°.The optimal algorithm selected in this paper can effectively improve the accuracy of GEDI L2A products for estimating ground elevation and forest canopy height.

关 键 词：GEDI 全波形激光雷达 地面高程 森林冠层高度 

分 类 号：P228.3[天文地球—大地测量学与测量工程]