文献类型：期刊文献

中文题名：三维解析辐射传输模型 ESRT 原理及其异质森林冠层光谱模拟应用

英文题名：Principles of the three-dimensional analytical radiative transfer model ESRT and its applications in simulating heterogeneous forest canopy spectra

作者：Li, Xiaoyao[1,2] Rao, Yueming[3,4] Zhang, Zhuoli[1] Wei, Shengrong[1] Qin, Pengyao[1] Tan, Bingxiang[1,2] Fu, Liyong[1]

第一作者：Li, Xiaoyao

机构：[1] Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Beijing, 100091, China; [2] Key Laboratory of Forestry Remote Sensing and Information System, National Forestry and Grassland Administration, Beijing, 100091, China; [3] Northwest Surveying and Planning Institute, National Forestry and Grassland Administration, Xi’an, 710048, China; [4] Key Laboratory of National Forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, National Forestry and Grassland Administration, Xi’an, 710048, China

年份：2025

卷号：29

期号：4

起止页码：976-989

外文期刊名：National Remote Sensing Bulletin

收录：EI(收录号：20251818359411)

语种：中文

外文关键词：Optical remote sensing - Sensitivity analysis - Stochastic models

摘要：The complicated spatial heterogeneity in forest scenes may have an effect on canopy reflectance. How to address heterogeneity is a challenge in the field of radiative transfer modeling. To overcome the accuracy limitations of classical analytical models caused by simplified scenarios and the efficiency limitations of computer simulation models in large-scale applications, we developed a three-dimensional analytical radiative transfer model called ESRT based on stochastic radiative transfer theory. At present, the application of ESRT in different complex forest scenes still needs to be explored, and additional field data are essential for model verification. This study introduces the basic principles and input–output parameters of the ESRT model, in which two key input parameters were proposed to express different heterogeneous canopy structures: (1) the intercanopy heterogeneity index (yr), representing the ratio of tree crowns with different optical properties to the total number of trees; (2) the intracrown heterogeneity index (yi), denoting the ratio of elements with different optical properties within a single tree crown to the total number of elements. To evaluate the model performance in simulating different kinds of heterogeneous forest canopy spectra, 21 30 m×30 m sample plots in mixed forests and 50 10 m × 10 m quadrats in pest-damaged forests were set up with individual tree measurements and remote sensing data acquirements. Control experiments based on the original SRT model and the three-dimensional model LESS were conducted for the two cases to compare simulation results with the extended ESRT model. On the basis of the framework of ESRT, sensitivity analyses were conducted to reveal the effect of mixing and pest levels on forest canopy spectra. Results showed that compared with the original SRT model simulations, the canopy spectra simulated by the extended ESRT model have better consistency with the measured spectra from the sample plots for the cases of mixed forests (R2=0.77, RMSE=0.075) and pest-damaged forests (R2=0.64, RMSE=0.039), and the simulation accuracy is closer to that of a 3D computer model. The conifer–broadleaf ratio and the vertical distribution of damaged foliage can affect the canopy spectral signals. In mixed forests, the canopy NDVI decreases with the decrease in forest coverage and with the increase in coniferous tree species proportion. Canopy coverage is the main factor affecting NDVI when the coverage is low, but the effect of mixing on NDVI becomes more apparent when the coverage is high. In pest-damaged forests, the sensitivity of BRF to yi varies considerably with damage types. The BRF of the bottom damaged forest exhibits a slight change at reduced yi and then shows a sharp change toward the maximum of yi. On the contrary, the BRF of the top damaged forest changes dramatically at reduced yi but levels off at increased yi. The three-dimensional analytical model ESRT balances the simulation accuracy of three-dimensional structures with the simulation efficiency of classical analytical models, resolving the difficulty in accurately and efficiently simulating radiation transfer in the presence of heterogeneity. The computation time is suitable for large-scale heterogeneous forest canopies. The extended ESRT can simulate forests with mixed canopy types and heterogeneous leaf distribution structures within the canopy, potentially aiding forest managers in more accurately and effectively monitoring forest dynamic changes. ? 2025 Science Press. All rights reserved.