Fig. 4: Trends of environmental variables and their partial correlation with NDVImax.
From: Decadal trends in global grassland growth peaks and their drivers since the 1980s
Variations of annual (a) air temperature (TA), (c) precipitation (PPT), (e) solar radiation (Rad), (g) CO2 concentration (CO2), (i) nitrogen deposition rate (Ndep), (k) cropland fraction (Cropland), and (m) rangeland fraction (Rangeland) for global grasslands during the periods of 1982–2021 and 1998–2009. Solid and dotted lines in (a, c, e, g, i, k, m) represent the linear regression trend over 1982–2021 and 1998–2009, with shaded bands representing 95% confidence intervals of the fitted trends. ***, **, *, and # indicated significant linear regression trend (two-sided t-tests of slope coefficients) at P < 0.001, P < 0.01, P < 0.05, and P < 0.1. Partial correlations between detrended NDVImax and (b) TA, (d) PPT, (f) Rad, (h) CO2, (j) Ndep, (l) Cropland, and (n) Rangeland are also shown. Source data are provided as a Source Data file.
