Table 3 The predictor variables used in this study.
From: Mapping 1-km soybean yield across China from 2001 to 2020 based on ensemble learning
Type | Variable Name | Description | Unit |
|---|---|---|---|
Climate Variables | Pre | Precipitation | mm |
Tmax | Maximum temperature | °C | |
Tmin | Minimum temperature | °C | |
PDSI | Palmer drought severity index | Dimensionless | |
SRAD | Solar radiation | W/m2 | |
VPD | Vapor pressure deficit | kPa | |
Remote Sensing Variables | SIF | Solar-induced chlorophyll fluorescence | mW·m−2·nm−1·sr−1 |
NPP | Net primary productivity | kg C/m | |
NDVI | Normalized difference vegetation index | Dimensionless | |
LSTd | Daytime land surface temperature | °C | |
Management Variables | year | Year | year |
SBZ | Soybean sub-zones | Dimensionless | |
AS | Ammonium sulfate Application | kg N/ha | |
MA | Manure Application | kg N/ha | |
NPK | Nitrogen, phosphorus and potassium compounds | kg N/ha | |
Urea | Urea Application | kg N/ha | |
ONS | Other nitrogen straight Application | kg N/ha | |
Soil Variables | SM | Soil moisture | mm |
pH | Potential of hydrogen | Dimensionless | |
OC | Organic carbon | % | |
CEC_SOIL | Cation exchange capacity of the soil | cmol/kg | |
REF_BULK | Reference bulk density | g/cm3 | |
CLAY | Clay content | % | |
SILT | Silt content | % |
