Mapping Tropical Forest Biomass by Combining ALOS-2, Landsat 8, and Field Plots Data
Abstract
:1. Introduction
2. Study Area and Dataset
2.1. Study Area
2.2. Satellite Dataset
3. Methodology
3.1. Field Biomass Estimation
3.2. Processing of Satellite Data
3.3. Accuracy Analysis
4. Results and Discussion
4.1. Estimates Using Single Sensor
4.2. Estimates Using Both Sensors
4.3. Validation of Biomass Models
4.4. Mapping of Aboveground Biomass
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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No. | Scene ID | Observation Date | Observation Angle | Polarizations | Season |
---|---|---|---|---|---|
1 | ALOS2040600240-150222-FBDR2.1GUA | 22 February 2015 | 32.9° | HH, HV | Dry |
2 | ALOS2040600250-150222-FBDR2.1GUA | 22 February 2015 | 32.9° | HH, HV | Dry |
No | ID | Observation Date | Path/ Row | Bands Used | Season |
---|---|---|---|---|---|
1 | LC81240512015289LGN00 | 16 October 2015 | 124/051 | B6, B5, B4, B8 | Rainy |
Month/Year | Daily Rainfall (mm) | Total Rainfall (mm) | ||||||||
---|---|---|---|---|---|---|---|---|---|---|
February 2015 | Days | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 0.0 |
Rainfall (mm) | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | ||
October 2015 | Days | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 40.5 |
Rainfall (mm) | 0.0 | 0.0 | 12.0 | 27.7 | 0.8 | 0.0 | 0.0 | 0.0 |
Parameter | Deciduous Forest | Evergreen Forest | |||||||
---|---|---|---|---|---|---|---|---|---|
Minimum | Maximum | Mean | Standard Deviation | Minimum | Maximum | Mean | Standard Deviation | ||
Diameter (m) | 8.14 | 38.52 | 18.29 | 6.73 | 16.87 | 48.74 | 19.39 | 13.33 | |
Height (m) | 6.33 | 38.52 | 10.97 | 2.93 | 10.01 | 18.23 | 12.18 | 3.14 | |
Biomass (Mg·ha−1) | 42.46 | 350.18 | 134.82 | 73.10 | 167.49 | 347.98 | 309.59 | 73.84 |
Parameter | Deciduous Forest | Evergreen Forest | |||||||
---|---|---|---|---|---|---|---|---|---|
Minimum | Maximum | Mean | Standard Deviation | Minimum | Maximum | Mean | Standard Deviation | ||
Diameter (m) | 9.89 | 39.41 | 16.74 | 6.17 | 12.51 | 44.82 | 20 | 15.11 | |
Height (m) | 6.06 | 17.67 | 10.635 | 2.73 | 6.17 | 17.67 | 12.95 | 4.57 | |
Biomass (Mg·ha−1) | 63.45 | 324.75 | 137.99 | 69.8 | 56.19 | 347.21 | 308.34 | 135.07 |
Model | Parameter used | R2 | RMSE |
---|---|---|---|
Model 1 | Max NDVI | 0.43 | 60.45 |
Model 2 | σ°forest | 0.64 | 48.04 |
Model 3 | SAR textures * | 0.36 | 64.06 |
Model 4 | HV, HH | 0.57 | 52.51 |
Model | Parameter Used | Training Model | Validation Model | Significance F | ||
---|---|---|---|---|---|---|
R2 | RMSE | R2 | RMSE | |||
Model 5 | Max NDVI and SAR textures * | 0.62 | 49.36 | 0.60 | 55.13 | 3 × 10−7 |
Model 6 | HV and SAR textures * | 0.66 | 46.69 | 0.63 | 44.64 | 3 × 10−8 |
Model 7 | Max NDVI, HV and SAR textures * | 0.73 | 41.60 | 0.70 | 39.10 | 7 × 10−1 |
Model 8 | Max NDVI, σ°forest, and SAR textures * | 0.75 | 35.18 | 0.74 | 35.88 | 3 × 10−1 |
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Viet Nguyen, L.; Tateishi, R.; Kondoh, A.; Sharma, R.C.; Thanh Nguyen, H.; Trong To, T.; Ho Tong Minh, D. Mapping Tropical Forest Biomass by Combining ALOS-2, Landsat 8, and Field Plots Data. Land 2016, 5, 31. https://doi.org/10.3390/land5040031
Viet Nguyen L, Tateishi R, Kondoh A, Sharma RC, Thanh Nguyen H, Trong To T, Ho Tong Minh D. Mapping Tropical Forest Biomass by Combining ALOS-2, Landsat 8, and Field Plots Data. Land. 2016; 5(4):31. https://doi.org/10.3390/land5040031
Chicago/Turabian StyleViet Nguyen, Luong, Ryutaro Tateishi, Akihiko Kondoh, Ram C. Sharma, Hoan Thanh Nguyen, Tu Trong To, and Dinh Ho Tong Minh. 2016. "Mapping Tropical Forest Biomass by Combining ALOS-2, Landsat 8, and Field Plots Data" Land 5, no. 4: 31. https://doi.org/10.3390/land5040031
APA StyleViet Nguyen, L., Tateishi, R., Kondoh, A., Sharma, R. C., Thanh Nguyen, H., Trong To, T., & Ho Tong Minh, D. (2016). Mapping Tropical Forest Biomass by Combining ALOS-2, Landsat 8, and Field Plots Data. Land, 5(4), 31. https://doi.org/10.3390/land5040031