A Comparative Analysis of SAR and Optical Remote Sensing for Sparse Forest Structure Parameters: A Simulation Study
Abstract
1. Introduction
2. Materials and Methods
2.1. Three-Dimensional Scene Construction
2.2. SAR and Optical Parameter Settings
2.3. Sensitivity Indicator
3. Results
3.1. Diameter at Breast Height
3.2. Height
3.3. Crown Width
3.4. LAI
3.5. Sensitivity at Different Angles
4. Discussion
4.1. Sensitivity of SAR Band and Polarization
4.2. Influence of Optical Band Selection
4.3. Effect of SAR Incidence Angle
4.4. Impact of Optical Observation Angle
4.5. Advantages and Challenges
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Model Input | Range | Default Value |
---|---|---|
DBH | 10–20 cm, step size 1 cm | 15 |
H | 16–26 m, step size 1 m | 20 |
CW | 2.5–5.5 m, step size 0.5 m | 3 |
LAI | 5–10 (step size 1), 15, 20, 30 | 20 |
DBH | C | L | P | |
---|---|---|---|---|
HH | min | −0.457 | −8.358 | −11.587 |
max | −0.370 | −8.225 | −11.258 | |
range | 0.087 | 0.132 | 0.329 | |
CV(%) | −6.73 | −0.40 | −1.00 | |
VV | min | −1.252 | −8.666 | −11.954 |
max | −1.226 | −8.633 | −11.902 | |
range | 0.025 | 0.033 | 0.052 | |
CV(%) | −0.66 | −0.10 | −0.17 | |
HV | min | −14.098 | −13.058 | −16.925 |
max | −14.090 | −13.044 | −16.901 | |
range | 0.008 | 0.014 | 0.024 | |
CV(%) | −0.02 | −0.03 | −0.04 | |
VH | min | −14.196 | −13.228 | −17.273 |
max | −14.187 | −13.216 | −17.259 | |
range | 0.009 | 0.013 | 0.014 | |
CV(%) | −0.02 | −0.02 | −0.02 |
H | C | L | P | |
---|---|---|---|---|
HH | min | −0.861 | −8.680 | −11.928 |
max | −0.056 | −7.982 | −11.170 | |
range | 0.805 | 0.697 | 0.758 | |
CV(%) | −52.68 | −2.65 | −2.09 | |
VV | min | −1.754 | −9.128 | −12.367 |
max | −0.830 | −8.239 | −11.631 | |
range | 0.924 | 0.889 | 0.736 | |
CV(%) | −22.38 | −3.27 | −1.98 | |
HV | min | −14.688 | −13.698 | −17.564 |
max | −13.633 | −12.545 | −16.451 | |
range | 1.054 | 1.153 | 1.113 | |
CV(%) | −2.39 | −2.84 | −2.11 | |
VH | min | −14.741 | −13.791 | −17.780 |
max | −13.757 | −12.765 | −16.890 | |
range | 0.985 | 1.026 | 0.890 | |
CV(%) | −2.21 | −2.49 | −1.65 |
CW | C | L | P | |
---|---|---|---|---|
HH | min | −0.706 | −8.777 | −12.011 |
max | −0.425 | −8.302 | −11.154 | |
range | 0.281 | 0.475 | 0.857 | |
CV(%) | −17.26 | −1.79 | −2.54 | |
VV | min | −1.495 | −8.879 | −12.571 |
max | −1.198 | −8.639 | −11.336 | |
range | 0.298 | 0.240 | 1.235 | |
CV(%) | −7.74 | −1.05 | −3.57 | |
HV | min | −14.316 | −13.374 | −17.499 |
max | −14.076 | −13.048 | −16.468 | |
range | 0.241 | 0.326 | 1.031 | |
CV(%) | −0.60 | −0.77 | −2.07 | |
VH | min | −14.457 | −13.440 | −17.913 |
max | −14.141 | −13.216 | −16.620 | |
range | 0.316 | 0.224 | 1.292 | |
CV(%) | −0.73 | −0.66 | −2.56 |
LAI | C | L | P | |
---|---|---|---|---|
HH | min | −3.539 | −8.559 | −11.680 |
max | 0.279 | −7.406 | −11.072 | |
range | 3.818 | 1.153 | 0.608 | |
CV(%) | −63.39 | −4.48 | −1.63 | |
VV | min | −4.577 | −8.868 | −12.107 |
max | −0.432 | −7.771 | −11.559 | |
range | 4.144 | 1.097 | 0.548 | |
CV(%) | −45.95 | −4.07 | −1.41 | |
HV | min | −17.535 | −13.347 | −17.101 |
max | −13.321 | −12.034 | −16.502 | |
range | 4.214 | 1.313 | 0.599 | |
CV(%) | −8.41 | −3.19 | −1.09 | |
VH | min | −17.640 | −13.520 | −17.449 |
max | −13.402 | −12.145 | −16.809 | |
range | 4.239 | 1.375 | 0.640 | |
CV(%) | −8.39 | −3.31 | −1.13 |
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Mao, Z.; Deng, L.; Liu, X.; Wang, Y. A Comparative Analysis of SAR and Optical Remote Sensing for Sparse Forest Structure Parameters: A Simulation Study. Forests 2025, 16, 1244. https://doi.org/10.3390/f16081244
Mao Z, Deng L, Liu X, Wang Y. A Comparative Analysis of SAR and Optical Remote Sensing for Sparse Forest Structure Parameters: A Simulation Study. Forests. 2025; 16(8):1244. https://doi.org/10.3390/f16081244
Chicago/Turabian StyleMao, Zhihui, Lei Deng, Xinyi Liu, and Yueyang Wang. 2025. "A Comparative Analysis of SAR and Optical Remote Sensing for Sparse Forest Structure Parameters: A Simulation Study" Forests 16, no. 8: 1244. https://doi.org/10.3390/f16081244
APA StyleMao, Z., Deng, L., Liu, X., & Wang, Y. (2025). A Comparative Analysis of SAR and Optical Remote Sensing for Sparse Forest Structure Parameters: A Simulation Study. Forests, 16(8), 1244. https://doi.org/10.3390/f16081244