文献类型：期刊文献

中文题名：基于机载激光雷达的落叶松组分生物量反演

英文题名：Inversion of Biomass Components for Larix olgensis Plantation Using Airborne LiDAR

作者：洪奕丰[1,2] 张守攻[1] 陈伟[2] 陈东升[1] 项伟波[1] 庞勇[3]

第一作者：洪奕丰

机构：[1]中国林业科学研究院林业研究所国家林业和草原局林木培育重点实验室,北京100091;[2]国家林业和草原局华东调查规划设计院,浙江杭州310019;[3]中国林业科学研究院资源信息研究所,北京100091

年份：2019

卷号：32

期号：5

起止页码：83-90

中文期刊名：林业科学研究

外文期刊名：Forest Research

收录：CSTPCD;;Scopus;北大核心:【北大核心2017】；CSCD:【CSCD2019_2020】；

基金：国家自然基金重点项目(31430017)

语种：中文

中文关键词：生物量反演;机载激光雷达;组分生物量;落叶松

外文关键词：biomass inversion;airborne LiDAR;biomass component;Larix olgensis

分类号：S771.8

摘要：[目的]构建基于机载LiDAR的落叶松组分生物量反演模型,讨论不同方法对模型构建的影响。[方法]以地面实测样地数据和同步获取的机载LiDAR点云数据为数据源,分别采用多元线性回归(MLR)和随机森林(RF)方法,估测了长白落叶松的组分生物量,利用"刀切法"评价了模型的泛化能力。[结果]表明:(1)MLR筛选得到的H_(interval)、H_(80)、D_(10)、D_(20)与各组分生物量普遍表现为显著(P<0.05)或极显著水平(P<0.01)。(2)MLR模型的R^2高于0.82(枝、叶除外);RF模型的R^2均高于0.91,且均拥有较小rRMSE、TRE值。(3)MDI和MDA方法的变量相对重要值排序均能较好地体现LiDAR变量与生物量之间的关系,MDI在趋势性判断和阈值设定方面更具优势。[结论] LiDAR变量与组分生物量具有显著的相关性。RF拥有更好的拟合效果和泛化能力,MLR则对LiDAR和组分生物量的关系有更明确的解释能力。反演模型能较好地反映林分的现势特征,生物量被低估的现象会随着林龄的增加而逐步增多。
[Objective] To establish the inversion models of biomass components for Larix olgensis plantation using Airborne LiDAR.[Method] Compatible models were established by combining dummy variable and nonlinear seemingly unrelated regression based on the biomass data of 64 trees in 40 sample plots of L. olgensis plantation. The canopy height indices and density indices were calculated from LiDAR point cloud data. Then the models based on these biomass components from field data and LiDAR indices were built using multivariate linear regression(MLR) and random forest regression(RF). The biomass model validation was accomplished by Jackknifing technique.[Result](1) There was a significant(P<0.05) or extremely significant(P<0.01) correlation between biomass components and Hinterval, H80, D10, and D20 which were screened using MLR.(2) The models had good estimation precision with R^2>0.82 and R^2>0.91 for MLR and RF, respectively.(3) The relationship between LiDAR variables and biomass could be reflected well by relative importance ranking of variables by both MDI and MDA method.[Conclusion] There is a good correlations between biomass components and LiDAR indices. RF shows stronger ability about fitting goodness and generalization, while MLR can make clearer interpretation of the relationship between LiDAR indices and biomass components. The present situation of L. olgensis plantation can be accurately reflected using inversion models, and the underestimation of component biomass will increase with the increase of stand age.