{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T17:43:56Z","timestamp":1772300636923,"version":"3.50.1"},"reference-count":53,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T00:00:00Z","timestamp":1692921600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["31971654"],"award-info":[{"award-number":["31971654"]}]},{"name":"National Natural Science Foundation of China","award":["D040114"],"award-info":[{"award-number":["D040114"]}]},{"name":"Civil Aerospace Technology Advance Research Project","award":["31971654"],"award-info":[{"award-number":["31971654"]}]},{"name":"Civil Aerospace Technology Advance Research Project","award":["D040114"],"award-info":[{"award-number":["D040114"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Forests play a significant role in terrestrial ecosystems by sequestering carbon, and forest biomass is a crucial indicator of carbon storage potential. However, the single-frequency SAR estimation of forest biomass often leads to saturation issues. This research aims to improve the potential for estimating forest aboveground biomass (AGB) by feature selection based on a scattering mechanism and sensitivity analysis and utilizing a non-parametric model that combines the advantage of dual-frequency SAR data. By employing GF-3 and ALOS-2 data, this study explores the scattering mechanism within a coniferous forest by using results of target decomposition and the pixel statistics method. By selecting an appropriate feature (backscatter coefficients and polarization parameters) and using stepwise regression models and a non-parametric model (the random forest adaptive genetic algorithm (RF-AGA)), the results revealed that the RF-AGA model with feature selection exhibited excellent AGB estimation performance without obvious saturation (RMSE = 10.42 t\/ha, R2 = 0.93, leave-one-out cross validation). The \u03c3HV, \u03c3VH, Pauli three-component decomposition, Yamaguchi three-component decomposition, and VanZyl3 component decomposition of thee C-band and \u03c3HV, \u03c3VH,\u03c3HH, Yamaguchi three-component decomposition, and VanZyl3 component decomposition of the L-band are suited for estimating the AGB of coniferous forests. Volume scattering was the dominant mechanism, followed by surface scattering, while double-bounce scattering had the smallest proportion. This study highlights the potential of investigating scattering mechanisms, sensitivity factors, and parameter selection in the C- and L-band SAR data for improved forest AGB estimation.<\/jats:p>","DOI":"10.3390\/rs15174194","type":"journal-article","created":{"date-parts":[[2023,8,28]],"date-time":"2023-08-28T05:46:47Z","timestamp":1693201607000},"page":"4194","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Improving the Potential of Coniferous Forest Aboveground Biomass Estimation by Integrating C- and L-Band SAR Data with Feature Selection and Non-Parametric Model"],"prefix":"10.3390","volume":"15","author":[{"given":"Yifan","family":"Hu","sequence":"first","affiliation":[{"name":"Key Laboratory of Sustainable Forest Ecosystem Management, School of Forestry, Northeast Forestry University, Ministry of Education, Harbin 150040, China"}]},{"given":"Yonghui","family":"Nie","sequence":"additional","affiliation":[{"name":"Key Laboratory of Sustainable Forest Ecosystem Management, School of Forestry, Northeast Forestry University, Ministry of Education, Harbin 150040, China"}]},{"given":"Zhihui","family":"Liu","sequence":"additional","affiliation":[{"name":"International Institute for Earth System Science, Nanjing University, Nanjing 210023, China"}]},{"given":"Guoming","family":"Wu","sequence":"additional","affiliation":[{"name":"Jiamusi Forestry and Grassland Administration, Jiamusi 154000, China"}]},{"given":"Wenyi","family":"Fan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Sustainable Forest Ecosystem Management, School of Forestry, Northeast Forestry University, Ministry of Education, Harbin 150040, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,25]]},"reference":[{"key":"ref_1","unstructured":"Stocker, T.F., Qin, D., Plattner, G.K., Tignor, M.M., Allen, S.K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P.M. 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