Marmot disturbances in a Mongolian steppe vegetation

We conducted a study in Mongolia on the Stipa steppe, which is the main habitat for the Siberian marmot (Marmota sibirica). The marmots create mounds that differ greatly in vegetation cover. Three types of mounds were distinguished, depending on the species dominating the vegetation on the mounds: an Artemisia type of mound, Leymus type and a Stipa type. It is hypothesized that the three types of mound represent a series of succession. The activities of the marmots lead to enhanced forage quality on the Artemisia and Leymus types of mound, as indicated by increased nitrogen concentrations in the on-mound vegetation. (c) 2006 Elsevier Ltd. All rights reserved.