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Regression-predicted annual changes in grassland NPP between 1988 and 2012. (A) Different grassland types. The definitions of MDW, ASAG, ASAM and DG used here are the same as in Fig. 2. (B) NNRs. Curves in this case were fitted using a conditional three-level growth model (Table S2, Model 6). The definitions of core, buffer, and trial zones used here are the same as in Fig. 1A.
