The effect of climate and grazing interaction on plant-plant relations
We found significant effects of both grazing and aridity on the outcome of plant-plant interactions, expressed by the RII indices. In particular, the RII indices for species richness, abundances, and Shannon diversity were all positive in high aridity/high grazing conditions. The RII values were neutral (i.e. not significantly different from zero) for species richness and Shannon diversity in the low aridity/low grazing conditions and also for Shannon diversity in the low aridity/high grazing and even negative for RII-cover in low aridity/low grazing regime (Table 2).