Forest Variable Estimation Using Radargrammetric Processing of TerraSAR-X Images in Boreal Forests

Remote Sensing

Henrik Persson¹ 

关键词: radargrammetry;    forestry;    X-band;    stereogrammetric methods;    SAR;    TerraSAR-X;   

DOI  :  10.3390/rs6032084

来源: mdpi

【 摘 要 】

The last decade has seen launches of radar satellite missions operating in X-band with the sensors acquiring images with spatial resolutions on the order of 1 m. This study uses digital surface models (DSMs) extracted from stereo synthetic aperture radar images and a reference airborne laser scanning digital terrain model to calculate the above-ground biomass and tree height. The resulting values are compared to in situ data. Analyses were undertaken at the Swedish test sites Krycklan (64°N) and Remningstorp (58°N), which have different site conditions. The results showed that, for 459 forest stands in Remningstorp, biomass estimation at the stand level could be performed with 22.9% relative root mean square error, while the height estimation showed 9.4%. Many factors influenced the results and it was found that the topography has a significant effect on the generated DSMs and should therefore be taken into consideration when the stand level mean slope is above four degrees. Different tree species did not have a major effect on the models during leaf-on conditions. Moreover, correct estimation within young forest stands was problematic. The intersection angles resulting in the best results were in the range 8–16°. Based on the results in this study, radargrammetry appears to be a promising potential remote sensing technique for future forest applications.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland