Trends in vegetation productivity related to climate change in China’s Pearl River Delta

shrubland regions is positively correlated with temperature (r = 0.5–0.7) for all seasons of the year. This significant positive correlation of ecosystem productivity with temperature in the non-growing season (Trough) represents a positive impact on forest growth from the Table 2. Summary statistics of trends in phenometrics according to LULC class, greening, and browning pixels. Metric Class r slope p-value TC Metric Class r slope p-value TC Mean Growing Season (MGS) Greening � 0.75 0.0022 0.0000 0.07 Position of Trough (POT) Greening� 0.31 0.370 0.0726 12.58 Browning� -0.88 -0.0042 0.0886 -0.14 Browning� 0.34 0.560 0.0465 19.04 Forest� 0.47 0.0009 0.0053 0.03 Forest -0.03 -0.040 0.8620 -1.37 Mixed� 0.54 0.0011 0.0010 0.04 Mixed 0.21 0.244 0.2400 8.30 Cropland� 0.46 0.0009 0.0064 0.03 Cropland� 0.54 0.617 0.0009 20.98 Shrubland� 0.64 0.0014 0.0000 0.05 Shrubland 0.23 0.280 0.1870 9.52 Maximum NDVI in Season (Peak) Greening � 0.66 0.0018 0.0000 0.06 Start of Season Greening 0.16 0.192 0.3690 6.53 Browning� -0.87 -0.0049 0.0674 -0.16 Browning� 0.30 0.363 0.0799 12.34 Forest� 0.4 0.0009 0.0206 0.03 Forest -0.16 -0.225 0.3740 -7.65 Mixed� 0.44 0.0009 0.0100 0.03 Mixed -0.04 -0.037 0.8460 -1.27 Cropland� 0.37 0.0008 0.0316 0.03 Cropland� 0.37 0.303 0.0329 10.30 Shrubland� 0.54 0.0011 0.0010 0.04 Shrubland 0.06 0.072 0.7410 2.43 Maximum NDVI in Season (Trough) Greening� 0.81 0.0031 0.0000 0.11 End of Season (EOS) Greening� 0.66 1.120 0.0000 38.08

Browning� -0.39 -0.0007 0.0233 -0.02 Browning� -0.39 -0.513 0.0237 -17.44 Forest� 0.4 0.0011 0.0207 0.04 Forest� 0.44 0.593 0.0085 20.16 Mixed� 0.61 0.0017 0.0001 0.06 Mixed� 0.59 0.716 0.0002 24.34 Cropland� 0.78 0.0023 0.0000 0.08 Cropland� 0.41 0.469 0.0169 15.95 Shrubland� 0.71 0.0022 0.0000 0.08 Shrubland� 0.44 0.616 0.0101 20.94 Position of Peak (POP) Greening 0.01 0.0055 0.9820 0.19 Length of Season (LOS) Greening 0.17 0.238 0.3460 8.09 Browning� -0.43 -0.5790 0.0119 -19.69 Browning� -0.50 -1.010 0.0024 -34.34 Forest -0.09 -0.1460 0.6070 -4.96 Forest 0.11 0.141 0.5390 4.79 Mixed -0.05 -0.0589 0.7930 -2.00 Mixed 0.14 0.144 0.4330 4.90 Cropland -0.04 -0.0349 0.8140 -1.19 Cropland -0.17 -0.191 0.3390 -6.49 Shrubland -0.06 -0.0788 0.7460 -2.68 Shrubland -0.03 -0.0474 0.8680 -1.61 TC shows total change obtained by multiplying slope of the fitted model by the length of the time series). � denotes a significant trend. https://doi.org/10.1371/journal.pone.0245467.t002 Fig 5. Trends of summer rainfall and sunshine hours in the PRD. (a) Spatially averaged summer rainfall, (b) annual average time series of sunshine hours. https://doi.org/10.1371/journal.pone.0245467.g005 PLOS ONE Climate and vegetation trends in the Pearl River Delta PLOS ONE | https://doi.org/10.1371/journal.pone.0245467 February 24, 2021 10 / 20