摘要
植被高度是动态监测植被生长状况的重要参数。机载激光雷达测量(LiDAR)因其良好的穿透力常用于森林高度反演,而鲜有应用LiDAR反演低矮植被高度的研究。本研究以皋兰生态与农业综合研究站为研究区,使用大疆禅思L1激光雷达在不同飞行高度、悬停时间、定位系统(基于网络进行差分计算的Nrtk定位系统与基于移动接收器进行差分计算的Drtk定位系统)下获取不同植被的点云数据,以探究飞行参数对于反演精度的影响。结果表明:Drtk与Nrtk定位系统精度相当,无网络时Drtk系统可替代Nrtk使用。悬停时间5 s与10 s的精度差异不大,10 s的精度略高。当植被高度低于60 cm时,飞行高度宜设为20 m;植被高度大于60 cm时,飞行高度可设为40 m以扩大采样范围。在反演精度方面,当植被高度低于30 cm时,反演误差在±30%内;而当植被高度大于40 cm时,则呈现出明显的低估现象。本研究对于应用大疆禅思L1激光雷达进行大范围低矮植被高度获取的相关研究具有重要的现实意义。
The plant community height is an important factor that reflects vegetation growth.LiDAR technology is often used for forestry height inversion because of its penetration;however,its application in low vegetation height inversion remains limited.We used DJI L1 LiDAR to extract vegetation point cloud data under different flight altitudes,hovering times,and positioning systems at Gaolan Ecological and Agricultural Research Station.We compared the calculation and field measurement results to explore the influence of different factors.The results indicated that the Drtk and Nrtk positioning system accuracies were similar.The Drtk system could be used when there was no network.Although the inversion accuracy of a 10 s hover time was slightly higher,there was no significant difference in the accuracy between the 5 s and 10 s hovering times.When the vegetation height was<60 cm,the flight height could be set to 20 m,and when the vegetation height was>60 cm,the flight height could be set to 40 m to expand the sampling range.The results showed that when the vegetation height was<30 cm,the inversion errors were within±30%.However,there was an apparent underestimation when the vegetation height was>40 cm.The results of this study are helpful for the application of DJI L1 LiDAR to obtain the height of low vegetation in a large area.
作者
阚鸿程
张慧芳
孟宝平
宜树华
KAN Hongcheng;ZHANG Huifang;MENG Baoping;YI Shuhua(Institute of Fragile Eco-environment/School of Geographic Science,Nantong University,Nantong 226019,Jiangsu,China)
出处
《草业科学》
CAS
CSCD
北大核心
2023年第10期2513-2527,共15页
Pratacultural Science
基金
国家自然科学基金项目(42071056)
国家自然科学基金青年项目(41801023)。
关键词
植被高度
点云
无人机
飞行高度
悬停时间
草地
农作物
plant community height
point cloud
unmanned aerial vehicle(UAV)
flight height
hover time
grassland
crops
