干旱区生态环境知识资源中心

The argali (Ovis ammon) is a species of great conservation concern throughout its range in central Asia and is particularly sensitive to human disturbance and habitat degradation Recent increases in livestock numbers have potentially reduced the capacity of habitats to sustain argali because of forage or interference competition We studied the potential for forage competition between argali and domestic livestock in Ikh Nart Nature Reserve Mongolia by quantifying overlap among seasonal diets using microhistological analysis of fecal samples We collected 100 fecal samples from argali and 100 fecal samples from livestock during June 2002 August 2002 January 2003 and April 2003 Argali and livestock used the same plant species with the exception of five used only by livestock We also quantified forage availability in both summer (2002) and winter (2003) seasons Total mean biomass in summer ((x) over bar = 19 0g/m(2)) declined similar to 82% to a winter mean of 3 5 g/m(2) (t = 1000 P < 0 0001) Dietary overlap between argali and livestock was high varying from 72% in summer to 95% in winter We concluded that high degree of overlap for forage coupled with the low available vegetative biomass in winter suggests the potential for competition between argali and livestock (C) 2010 Elsevier Ltd All rights reserved