Aboveground Biomass Estimation in Short Rotation Forest Plantations in Northern Greece Using ESA’s Sentinel Medium-High Resolution Multispectral and Radar Imaging Missions
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Analysis Workflow
2.3. In Situ Measurements
2.4. Remote Sensing Data and Preprocessing
Index | Formula | Reference |
---|---|---|
Sentinel 2 | ||
NDVI | [34] | |
NDWI | [35] | |
NDI45 | NDI45= | [36] |
MCARI | MCARI = | [37] |
PSSRa | [38] | |
GEMI | [39] | |
where | [39] | |
WET | [40] | |
RSR | RSR= | [41] |
EVI | [42] | |
GNDVI | GNDVI = | [43] |
Sentinel 1 | ||
VV | vertical transmit and vertical receive polarization | |
VH | vertical transmit and horizontal receive polarization |
2.5. Random Forest Modeling and Assessment
3. Results
4. Discussion
4.1. AGB Models Using Sentinel-1 and Sentinel-2 Data
4.2. Information Content of Individual Variables
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Trees per Ha | Height (m) | Diameter at Breast Height (cm) | Above Ground Biomass (Mg ha−1) | |
---|---|---|---|---|
Average | 1589 | 7.64 | 8.71 | 33.43 |
Range | 733–3522 | 0.5–22 | 3–28.7 | 4.41–98.12 |
Standard Deviation | 355 | 1.98 | 2.77 | 16.45 |
MONTH | NDVI | NDWI | NDI45 | MCARI | PSSRA | GEMI | WET | RSR | EVI | GNDVI |
---|---|---|---|---|---|---|---|---|---|---|
JANUARY | 0.00 | −0.02 | −0.03 | −0.11 | 0.01 | −0.09 | 0.04 | 0.12 | −0.07 | 0.04 |
FEBRUARY | 0.11 | 0.05 | 0.13 | −0.03 | 0.12 | −0.02 | 0.14 | 0.30 ** | −0.02 | 0.13 |
MARCH | 0.13 | 0.06 | 0.09 | −0.11 | 0.14 | 0.01 | 0.18 | 0.26 ** | −0.02 | 0.16 |
APRIL | 0.20 * | 0.15 | 0.21 * | 0.05 | 0.22 * | 0.16 | 0.17 | 0.23 * | 0.13 | 0.15 |
MAY | 0.22 * | 0.37 ** | 0.18 | 0.21 * | 0.24 * | 0.34 ** | 0.32 ** | 0.10 | 0.41 ** | 0.21 * |
JUNE | 0.39 ** | 0.48 ** | 0.34 ** | 0.27 ** | 0.39 ** | 0.51 ** | 0.35 ** | 0.28 ** | 0.48 ** | 0.36 ** |
JULY | 0.60 ** | 0.64 ** | 0.63 ** | 0.38 ** | 0.60 ** | 0.62 ** | 0.62 ** | 0.59 ** | 0.60 ** | 0.53 ** |
AUGUST | 0.28 ** | 0.63 ** | 0.32 ** | 0.52 ** | 0.30 ** | 0.39 ** | 0.64 ** | 0.31 ** | 0.54 ** | 0.20 * |
SEPTEMBER | 0.54 ** | 0.51 ** | 0.62 ** | 0.31 ** | 0.55 ** | 0.49 ** | 0.51 ** | 0.55 ** | 0.41 ** | 0.48 ** |
OCTOBER | 0.38 ** | 0.37 ** | 0.45 ** | 0.38 ** | 0.39 ** | 0.35 ** | 0.41 ** | 0.37 ** | 0.33 ** | 0.30 ** |
NOVEMBER | 0.15 | 0.08 | 0.21 * | 0.09 | 0.17 | 0.05 | 0.11 | 0.20 * | 0.05 | 0.15 |
DECEMBER | 0.24 * | −0.01 | 0.20 * | −0.06 | 0.22 * | 0.01 | 0.11 | 0.29 ** | −0.02 | 0.21 * |
MONTH | VV | VH | MONTH | VV | VH |
---|---|---|---|---|---|
JANUARY | 0.12 | 0.47 ** | July | 0.29 ** | 0.34 ** |
FEBRUARY | 0.23 * | 0.44 ** | August | 0.18 | 0.22 * |
MARCH | 0.35 ** | 0.29 ** | September | 0.22 * | 0.35 ** |
APRIL | 0.19 | 0.28 ** | October | 0.27 ** | 0.07 |
MAY | 0.27 ** | 0.28 ** | November | 0.14 | 0.26 ** |
JUNE | 0.11 | 0.14 | December | 0.24 * | 0.25 * |
S2 | S2/S1_VV | S2/S1_VH | S2/S1 | |||||
---|---|---|---|---|---|---|---|---|
Month | R2 | RMSE | R2 | RMSE | R2 | RMSE | R2 | RMSE |
January | −0.17 | 17.62 | −0.06 | 16.79 | 0.05 | 15.95 | 0.05 | 15.81 |
February | −0.23 | 17.94 | −0.09 | 17.04 | 0.04 | 15.80 | 0.08 | 15.62 |
March | −0.16 | 17.37 | 0.00 | 16.16 | 0.00 | 16.41 | 0.06 | 15.88 |
April | 0.03 | 16.06 | 0.06 | 15.70 | 0.11 | 15.39 | 0.12 | 15.25 |
May | 0.11 | 15.27 | 0.11 | 15.22 | 0.11 | 15.19 | 0.11 | 15.25 |
June | 0.08 | 15.53 | 0.07 | 15.73 | 0.08 | 15.60 | 0.07 | 15.85 |
July | 0.37 | 12.87 | 0.36 | 13.01 | 0.38 | 12.81 | 0.37 | 12.83 |
August | 0.52 | 11.26 | 0.50 | 11.47 | 0.51 | 11.40 | 0.50 | 11.54 |
September | 0.37 | 12.99 | 0.36 | 12.95 | 0.36 | 12.93 | 0.37 | 12.99 |
October | 0.19 | 14.73 | 0.18 | 14.77 | 0.19 | 14.58 | 0.20 | 14.61 |
November | 0.10 | 15.45 | 0.09 | 15.47 | 0.10 | 15.48 | 0.11 | 15.47 |
December | −0.08 | 16.96 | −0.04 | 16.71 | −0.05 | 16.89 | −0.06 | 16.79 |
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Theofanous, N.; Chrysafis, I.; Mallinis, G.; Domakinis, C.; Verde, N.; Siahalou, S. Aboveground Biomass Estimation in Short Rotation Forest Plantations in Northern Greece Using ESA’s Sentinel Medium-High Resolution Multispectral and Radar Imaging Missions. Forests 2021, 12, 902. https://doi.org/10.3390/f12070902
Theofanous N, Chrysafis I, Mallinis G, Domakinis C, Verde N, Siahalou S. Aboveground Biomass Estimation in Short Rotation Forest Plantations in Northern Greece Using ESA’s Sentinel Medium-High Resolution Multispectral and Radar Imaging Missions. Forests. 2021; 12(7):902. https://doi.org/10.3390/f12070902
Chicago/Turabian StyleTheofanous, Nikos, Irene Chrysafis, Giorgos Mallinis, Christos Domakinis, Natalia Verde, and Sofia Siahalou. 2021. "Aboveground Biomass Estimation in Short Rotation Forest Plantations in Northern Greece Using ESA’s Sentinel Medium-High Resolution Multispectral and Radar Imaging Missions" Forests 12, no. 7: 902. https://doi.org/10.3390/f12070902