Use of TanDEM-X PolInSAR for canopy height retrieval over tropical forests in the Western Ghats, India
Use of TanDEM-X PolInSAR for canopy height retrieval over tropical forests in the Western Ghats, India
Blog Article
Canopy height is a critical parameter in quantifying the vertical structure of forests.Polarimetric SAR Interferometry (PolInSAR) is a radar remote sensing technique that makes use Horse Brushing Boots of polarimetric separation of scattering phase centers obtained from interferometry to estimate height.This article discusses the potential of the X-band PolInSAR pair for forest height retrieval over tropical forests in the Western ghats.
A total of 19 fully polarimetric datasets with various spatial baselines acquired from November 2015 to February 2016 in bistatic mode are utilized in this study.After compensating for all possible non-volumetric decorrelations in the data-sets, the remaining volume decorrelation is modeled using a Random Volume Over Ground (RVoG) model to invert height from PolInSAR data.A modified three-stage algorithm developed by Cloude and Papathanassiou (2003) is adopted for height inversion.
PolInSAR derived heights were cross-validated against reference height data measured during a field survey conducted in March 2019.RMSE values of all TerraSAR-X/TanDEM-X PolInSAR heights with respect to field measured heights range from 3.3 to 13.
8 m and the correlation coefficient r2 varies between 0.16 and 0.79.
The results suggest that the use of a dataset with optimal wavenumber can improve the tree height estimation process.The best performance was achieved for the dataset acquired on 11 December 2015 with RMSE = 3.4 m and r2 = 0.
79.Furthermore, the effects of parameters such as angle of incidence, precipitation, and forest biomass on height inversion accuracy are assessed.A large-scale Shimoga Forest height map was generated using multiple TanDEM-X acquisitions with the best correlation results.
To improve the accuracy of the height estimation, a merged height approach is explored.The best height estimates among all PolInSAR estimates for King Upholstered Bed a given field plot are chosen in this regard.The merged height approach gave rise to an improved inversion accuracy with RMSE = 1.
9 m and r2 = 0.92.The primary objective of this study was to demonstrate the ability of spaceborne X-band data to estimate height with maximum accuracy over natural forests in India, in which height retrieval research has seldom been done.