Table 2 Description of the 86 variables computed and extracted from the SPOT-6 and Landsat 5, 7, and 8 satellites images
Abbreviation | Source | Variable type | N | Description of image variables |
|---|---|---|---|---|
AGE | Ancillary | 1 | Age of the stand at the time of the forest inventory | |
B1, B2, B3, B4 | SPOT-6 | Spectral bands | 4 | Blue (B1), green (B2), red (B3), near-infrared (B4) reflectances |
RAT_Bx_By | SPOT-6 | Simple rations | 12 | Simple ratio: RAT_Bi_Bj = Bi/Bj, i ≠ j, with (Bi,Bj) being all pairs of bands |
NDVI | SPOT-6 | Vegetation index | 1 | Normalized Difference Vegetation Index (B4 − B3)/(B4 + B3) |
SAVI | SPOT-6 | Vegetation index | 1 | Soil Adjusted Vegetation Index (B4-B1)/(B4 + B1 + L) *(1 + L), where L = 0.5 |
ARVI | SPOT-6 | Vegetation index | 1 | Atmosphere Resistant Vegetation Index (B4 − B3 − γ*( B3 − B1)) / (B4 + B3 − γ*(B3 − B1)), where γ = 1 |
CON_Bx | SPOT-6 | Texture index | 4 | Band’s contrast (local variation of the intensity of a pixel and its neighbor): CON_B1 (band 1), CON_B2 (band 2), CON_B3 (band 3), CON_B4 (band 4) |
COR_Bx | SPOT-6 | Texture index | 4 | Band’s correlation (linear dependence in the reflectance between a pixel and its neighbor): COR_B1 (band 1), COR_B2 (band 2), COR_B3 (band 3), COR_B4 (band 4) |
ENE_Bx | SPOT-6 | Texture index | 4 | Band’s energy (evaluates the uniformity of the texture): ENE_B1 (band 1), ENE_B2 (band 2), ENE_B3 (band 3), ENE_B4 (band 4) |
HOM_Bx | SPOT-6 | Texture index | 4 | Band’s homogeneity (measures the regularity present in the image): HOM_B1 (band 1), HOM_B2 (band 2), HOM_B3 (band 3), HOM_B4 (band 4) |
MUL_Bx_CON_Bx | SPOT-6 | Texture index | 4 | Product of band reflectance and band contrast: MUL_B1_CON_B1 (B1 x CON_B1), MUL_B2_CON_B2 (B2 x CON_B2), MUL_B3_CON_B3 (B3 x CON_B3), MUL_B4_CON_B4 (B4 x CON_B4) |
MUL_Bx_COR_Bx | SPOT-6 | Texture index | 4 | Product of band reflectance and band correlation: MUL_B1_COR_B1 (B1 x COR_B1), MUL_B2_COR_B2 (B2 x COR_B2), MUL_B3_COR_B3 (B3 x COR_B3), MUL_B4_COR_B4 (B4 x COR_B4) |
MUL_Bx_ENE_Bx | SPOT-6 | Texture index | 4 | Product of band reflectance and band energy: MUL_B1_ENE_B1 (B1 x ENE_B1), MUL_B2_ENE_B2 (B2 x ENE_B2), MUL_B3_ENE_B3 (B3 x ENE_B3), MUL_B4_ENE_B4 (B4 x ENE_B4) |
MUL_Bx_HOM_Bx | SPOT-6 | Texture index | 4 | Product of band reflectance and the band homogeneity: MUL_B1_HOM_B1 (B1 x HOM_B1), MUL_B2_HOM_B2 (B2 x HOM_B2), MUL_B3_HOM_B3 (B3 x HOM_B3), MUL_B4_HOM_B4 (B4 x HOM_B4) |
RAT_Bx_CON_Bx | SPOT-6 | Texture index | 4 | Ratio of band reflectance and band contrast: RAT_B1_CON_B1 (B1/CON_B1), RAT_B2_CON_B2 (B2/CON_B2), RAT_B3_CON_B3 (B3/CON_B3), RAT_B4_CON_B4 (B4/CON_B4) |
RAT_Bx_COR_Bx | SPOT-6 | Texture index | 4 | Ratio of band reflectance and band correlation: RAT_B1_COR_B1 (B1/COR_B1), RAT_B1_COR_B1 (B2/COR_B2), RAT_B3_COR_B3 (B3/COR_B3), RAT_B4_COR_B4 (B4/COR_B4) |
RAT_Bx_ENE_Bx | SPOT-6 | Texture index | 4 | Ratio of band reflectance and band energy: RAT_B1_ENE_B1 (B1/ENE_B1), RAT_B2_ENE_B2 (B2/ENE_B2),RAT_B3_ENE_B3 (B3/ENE_B3), RAT_B4_ENE_B4 (B4/ENE_B4) |
RAT_Bx_HOM_Bx | SPOT-6 | Texture index | 4 | Ratio of band reflectance and band homogeneity: RAT_B1_HOM_B1 (B1/HOM_B1), RAT_B2_HOM_B2(B2/HOM_B2), RAT_B3_HOM_B3 (B3/HOM_B3), RAT_B4_HOM_B4 (B4/HOM_B4) |
INT_0_DS | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to the last satellite collection date (17/08/2018) |
INT_0_DM | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to inventory measurement date |
INT_0_1 | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to 1-year-old |
INT_0_2 | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to 2-year-old |
INT_0_MIN | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to minimum NDVI (minimum NDVI after 2-year-old) |
INT_0_MAX | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from planting date to maximum NDVI |
MAX_MIN | Landsat 5, 7 e 8 | Time series | 1 | Difference (INT_0_MAX—INT_0_MIN) |
INT_1_DS | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 1 year after planting to the last satellite collection date (17/08/2018) |
INT_1_DM | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 1 year after planting to the inventory measurement date |
INT_1_MIN | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 1 year after planting to the minimum NDVI (minimum NDVI after 2-year-old) |
INT_1_MAX | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 1 year after planting to the maximum NDVI |
INT_2_DS | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 2 years after planting to the satellite collection date (17/08/2018) |
INT_2_DM | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 2 years after planting to the inventory measurement date |
INT_2_MIN | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 2 years after planting to the minimum NDVI (minimum NDVI after 2-year-old) |
INT_2_MAX | Landsat 5, 7 e 8 | Time series | 1 | Cumulative NDVI from 2 years after planting to the maximum NDVI |
NDVI_ 2_MIN | Landsat 5, 7 e 8 | Time series | 1 | Minimum NDVI value after 2-year-old |
NDVI_ 2_MAX | Landsat 5, 7 e 8 | Time series | 1 | Maximum NDVI value after 2-year-old |
MAX_MIN_NDVI | Landsat 5, 7 e 8 | Time series | 1 | Difference (NDVI_2_MAX—NDVI _2_MIN) |