Carbon stock estimation by dual-polarized synthetic aperture radar (SAR) and forest inventory data in a Mediterranean forest landscape

作     者：Can Vatandaşlar Saygin Abdikan Can Vatanda?lar;Saygin Abdikan

作者机构：Department of Forest EngineeringArtvin Coruh University08100ArtvinTurkey Department of Geomatics EngineeringHacettepe University06800AnkaraTurkey 

出 版 物：《Journal of Forestry Research》 (林业研究（英文版）)

年 卷 期：2022年第33卷第3期

页      面：827-838页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 0907[农学-林学] 09[农学] 0829[工学-林业工程] 0903[农学-农业资源与环境] 0901[农学-作物学] 

基　　金：The authors thank the Republic of Turkey General Directorate of Forest (GDF) for providing the study area’s forest management plan and its spatial database. 

主　　题：Carbon storage Aboveground carbon Soil-bound carbon Forest biomass Synthetic aperture radar(SAR) 

摘      要：Forest ecosystems play a crucial role in mitigating global climate change by forming massive carbon sinks. Their carbon stocks and stock changes need to be quantified for carbon budget balancing and international reporting schemes. However, direct sampling and biomass weighing may not always be possible for quantification studies conducted in large forests. In these cases, indirect methods that use forest inventory information combined with remote sensing data can be beneficial. Synthetic aperture radar (SAR) images offer numerous opportunities to researchers as freely distributed remote sensing data. This study aims to estimate the amount of total carbon stock (TCS) in forested lands of the Kizildag Forest Enterprise. To this end, the actual storage capacities of five carbon pools, i.e. above- and below-ground, deadwood, litter, and soil, were calculated using the indirect method based on ground measurements of 264 forest inventory plots. They were then associated with the backscattered values from Sentinel-1 and ALOS-2 PALSAR-2 data in a Geographical Information System (GIS). Finally, TCS was separately modelled and mapped. The best regression model was developed using the HH polarization of ALOS-2 PALSAR-2 with an adjusted R^(2) of 0.78 (p 0.05). According to the model, the estimated TCS was about 2 Mt for the entire forest, with an average carbon storage of 133 t ha^(−1). The map showed that the distribution of TCS was heterogenic across the study area. Carbon hotspots were mostly composed of pure stands of Anatolian black pine and mixed, over-mature stands of Lebanese cedar and Taurus fir. It was concluded that the total carbon stocks of forest ecosystems could be estimated using appropriate SAR images at acceptable accuracy levels for forestry purposes. The use of additional ancillary data may provide more delicate and reliable estimations in the future. Given the implications of this study, the spatiotemporal dynamics of carbon can be effectively controlled by forest management when coupled with easily accessible space-borne radar data.