Figure captionsFIGURE 1 Location of the study site and the watering and N fertilization experiment in the Artemisia ordosica community (from aerial view).FIGURE 2 Effects of water and N additions on relative interaction index for biomass and richness at the community level. For more detailed statistical results, see Table S1.FIGURE 3 (a) Redundancy analysis (RDA) conducted on RIIat species level (black arrows) and species functional traits (grey arrow). (b) Cluster based on RDA species scores. The two bar graphs inside panel (a) show the mean (± se) trait values of each cluster group with results of Tukey tests.*,P < 0.05, **, P < 0.01, ***, P < 0.001.FIGURE 4 Effects of watering and fertilization on mean biomass of herbaceous species of each cluster group in quadrats away from the shrubs (left panels) and RII (right panels). Asterisks above or below each RII bars indicate significant differences from 0 value. (*), P < 0.1,*, P < 0.05, **,P < 0.01, ***, P < 0.001. Significant effects of the two treatments and their interaction are given for each panel and cluster group and detailed statistical results can be seen see in Tables S3.