Location of the Loess Plateau in China (left plate) and the distribution of the 188 sampling sites where <i>in situ</i> measurements of aboveground net primary productivity were taken in the study area (right plate).

<p>Location of the Loess Plateau in China (left plate) and the distribution of the 188 sampling sites where <i>in situ</i> measurements of aboveground net primary productivity were taken in the study area (right plate).