Fig. 3.

Study sites in forests, shrublands, grasslands, and croplands across the country in the Strategic Priority Project of Carbon Budget supported by the Chinese Government. A total of 17,090 field plots were sampled in the project, of which 7,800 plots were from forests, 1,200 plots from shrublands, 4,030 plots from grasslands, and 4,060 soil sites from croplands. We excluded Taiwan, Hong Kong, Macao, and the South China Sea Islands from our study primarily because of difficulties of field access in these regions.