Table 1. Vegetation indices derived from ESA Sentinel-2 satellite mission. | |||

Vegetation index | Abbreviation | Formula | Reference |

Simple Ratio 800/2170 | SR | Malthus et al. (1993) | |

Mid-infrared Vegetation Index | MVI | Thenkabail et al. (2002) | |

Normalized Difference Red Edge | NDRE | Hunt et al. (2011) | |

Normalized Difference Vegetation Index | NDVI | Rouse et al. (1973) | |

Normalized Difference Moisture Index | NDMI | Wilson and Sader (2002) | |

Normalized Burn Ratio | NBR | Key and Benson (2005) | |

Atmospherically Resistant Vegetational Index | ARVI | Thenkabail et al. (2002) |

Table 2. Relative bias (RB), relative root mean squared error (RRMSE), expectation of the relative standard error estimator (ERSEE) and actual coverage of the nominal 95% confidence intervals (AC95) of first-phase coverage estimator, second-phase estimator based on the sole sample information and second-phase linear regression estimator of wood volume for the three artificial populations of poplar plantations with random, clustered, and trended spatial distributions. | ||||

Estimated attribute | Performance indexes | Random | Clustered | Trended |

coverage | RB (%) | 0.05 | 0.06 | 0.01 |

RRMSE (%) | 2.83 | 3.05 | 2.89 | |

ERSEE (%) | 2.94 | 3.22 | 3.07 | |

AC95(%) | 96.11 | 96.50 | 96.39 | |

wood volume (sole sample information) | RB (%) | –2.46 | –2.06 | –2.10 |

RRMSE (%) | 9.35 | 8.01 | 7.72 | |

ERSEE (%) | 9.34 | 8.04 | 7.64 | |

AC95(%) | 93.32 | 93.42 | 93.14 | |

wood volume (linear regression estimator) | RB (%) | –2.54 | –2.18 | –2.16 |

RRMSE (%) | 7.97 | 6.97 | 6.59 | |

ERSEE (%) | 7.63 | 6.73 | 6.33 | |

AC95(%) | 92.15 | 92.37 | 92.57 |

Table 3. Pearson correlation coefficient between wood volume of poplar plantations and vegetation indices from Sentinel-2 imagery. | |

Vegetation index (see Table 1) | Pearson coefficient |

SR | 0.63 |

MVI | 0.62 |

NDRE | 0.60 |

NDVI | 0.59 |

NDMI | 0.59 |

NBR | 0.59 |

ARVI | 0.58 |