Is Degradation a Major Problem in Semi-Desert Environments of the Gobi Region in Southern Mongolia?

This paper tests predictions derived from the non-equilibrium theory of rangeland science. Data were collected in livestock enclosures situated in the relatively moist desert steppes of the Gobi Gurvan Saykhan region of southern Mongolia from 2000 to 2003. Plant community composition and species’ richness in enclosures showed clear differences between years, but these were equally strong in ungrazed controls. Thus, changes were mainly attributed to differences in precipitation between years as opposed to grazing, as no significant effects thereof were detected. This was also confirmed by data on above-ground standing biomass. This changed tremendously over the years, with differences between various grazing regimes (factorial combination of grazing by livestock and small mammals) being smaller than interannual changes. The results support the idea that on a local scale desert steppes experience non-equilibrium dynamics with water availability being far more important than livestock impact. As a result, it can be presumed that the danger of anthropo-zoogenic degradation is small. However, a nomadic way of life appears to be a crucial precondition for sustainable land use of these environments, thus, further aspects than precipitation data alone need to be taken into account when assessing the dynamics of the ecosystem.