Fig. 2. Mean corrected intrinsic water use efficiency (IWUE_s) (+1 SE) averaged across C3 (filled bars) or C4 (open bars) or all species (bars with shadow) at a site, and mean IWUE_s (+1 SE) averaged across species in different vegetation type–degradation status combinations. Site information is in Table 1. Paired t tests indicated that mean site IWUE_s for C4 species was significantly higher than that for C3 species at the given site (p < 0.01). Open dots denote the mean IWUE_s for all species in nondegraded sites within a specific vegetation type, while filled dots indicate the mean IWUE_s for species in degraded sites.