Tree density and the 48 explanatory variables of the 4367 plots in North American boreal forests.

Location: North American boreal forestsSize: 4367 plotsType: ABMI, NFI, PSP plotsProv: province, territory or state where the plot isObs_Density: tree density from field measurement (trees/ha; DBH &gt;= 10.0 cm).Est_Crowther_Density: tree density estimates from Crowther et al.'s biome map (trees/ha).HumanDev: percent of developed and managed landHumanPop: population density (km^-2)Landcover: land cover type defined in the Land Cover Classification System (LCCS)Long: longitude (° W)Lat: latitude (° N)Elev: elevation (m)Slope: angle of inclination of the terrain (°)Eastness: sine of aspect of the terrain to northNorthness: cosine of aspect of the terrain to northTRI: terrain ruggedness indexStandht: stand height as mean height of the tallest 3 trees (m)Standht2: square of Standht (m²)Canopyht: canopy height from Sentinel-2 imagery (m)LAI: leaf area indexEVI: enhanced vegetation indexNDVI: normalized difference vegetation indexASM_EVI: angular second moment (orderliness) of EVIHomogeneity_EVI: similarity of EVI between adjacent pixelsContrast_EVI: exponentially weighted difference in EVI between adjacent pixelsDissimilarity_EVI: difference in EVI between adjacent pixelsTCECC: cation exchange capacity of the clay fraction in the topsoil (soil between 0 and 30 cm under the ground) (cmol kg^-1)TpHH2O: topsoil pH (in water)TC: topsoil carbon content (kg C m^-2)AET: actual evapotranspiration as water use (mm day^-1)Alpha: Priestley-Taylor alpha coefficient for soil water deficitnhx: anthropogenic NHx input (g N m^-2 year^-1)noy: anthropogenic NOy input (g N m^-2 year^-1)Evapotranspiration: Penman-Monteith reference evapotranspiration (mm day^-1)Aridity: ration between mean annual precipitation and mean annual Penman-Monteith reference evapotranspirationSolar_Radiation: incident solar radiation (kJ m^-2 day^-1)Wind: wind speed at 2 m above the ground (m s^-1)BIO1: Mean annual temperature (℃)BIO2: Mean diurnal range (mean of monthly difference between maximum and minimum temperature) (℃)BIO3: Isothermality (BIO2/BIO7 * 100)BIO4: Temperature seasonality (standard deviation of monthly temperature) (℃)BIO5: Maximum temperature of warmest month (℃)BIO6: Minimum temperature of coldest month (℃)BIO7: Temperature annual range (BIO5-BIO6) (℃)BIO8: Mean temperature of wettest quarter (℃)BIO9: Mean temperature of driest quarter (℃)BIO10: Mean temperature of warmest quarter (℃)BIO11: Mean temperature of coldest quarter (℃)BIO12: Annual precipitation (mm)BIO13: Precipitation of wettest month (mm)BIO14: Precipitation: driest month (mm)BIO15: Precipitation: seasonality (coefficient of variation of monthly precipitation; Standard deviation of BIO12/mean of BIO12 * 100)BIO16: Precipitation of wettest quarter (mm)BIO17: Precipitation: driest quarter (mm)BIO18: Precipitation of warmest quarter (mm)BIO19: Precipitation of coldest quarter (mm)<br>