Habitat Suitability Assessment Of Mongolian Gazelle (Procapra Gutturosa) In The Dalai Lake Area, Inner Mongolia

We selected seven habitat factors, land cover type, vegetation coverage, slope, distance to water, distance to road, distance to settlement, distance to pasture, as the key factors affecting habitat suitability of Mongolian gazelle (Procapra gutturosa) based on the research conclusions on the habitat selection of the Mongolian gazelle and established the single habitat factor evaluating criteria of the Mongolian gazelle habitat suitability evaluation system. The land cover type and vegetation coverage was extracted from remote sensing images, based on the previous studies and the field investigation. The suitability assessment model was established by the spatial analysis model (a model of Arc MAP 9.2), then overlaid the four data layers not concerning the effect of human disturbance to get the habitat suitability distribution of potential habitat, and overlaid the seven data layers to get the habitat suitability distribution of actual habitat. Bharhut Mongolian gazelle protected area lay inside the Dalai Lake area. The landscape pattern was analyzed by the FRAGSTATS3.3 based on the results of the habitat suitability assessment. According to comparing the results of habitat suitability assessment in the Dalai Lake area and the landscape pattern index change in the protect area; human disturbance effect on the habitat of the Mongolian gazelle was analyzed. And the conclusions were as the following:(1) The area of suitable habitat, moderate suitable habitat, general suitable habitat and unsuitable habitat were 572616.6ha,751134.2ha,506990. 1ha,1176006.2ha respectively in the Mongolian gazelle potential habitat; The area of suitable habitat, moderate suitable habitat, general suitable habitat and unsuitable habitat were 412885.8ha,546094.0ha,377777.3ha, 1666504.7ha respectively in the Mongolian gazelle actual habitat in the Dalai Lake area. The proportion of suitable habitat and moderate suitable habitat of the potential habitat was 44.0%, the proportion of unsuitable habitat was 39.1%; and the proportion of suitable habitat and moderate suitable habitat of the actual habitat was 31.9%, the proportion of unsuitable habitat was 55.5%. In the Dalai Lake area, suitable habitat, moderate suitable habitat, general suitable habitat of Mongolian gazelle actual habitat were reduced all above and beyond 25%, compared with the potential habitat, and unsuitable habitat was increased 41.7% compared with the potential habitat.(2) The Mongolian gazelle habitat became fragmented and the spatial heterogeneity reduced in Bharhut Mongolian gazelle protected area. The mean patch areas of suitable habitat, moderate suitable habitat, and general suitable habitat of the actual habitat were less than the potential habitat, but the mean patch area of unsuitable habitat of the actual habitat were greater than the potential habitat. The results showed that because of the human disturbance effect, the mean patch areas of suitable habitat, moderate suitable habitat, and general suitable habitat were reduced, and the patch fragmentation was aggravated; but the mean patch areas of unsuitable habitat was increased, and the patches gathered into big patches. The number of patch and patch density of the suitable habitat and moderate suitable habitat of actual habitat were greater than the potential habitat. The results showed that the number of patch and patch density of suitable habitat and moderate suitable habitat increased, and the patch fragmentation were aggravated due to the human disturbance effect. The mean perimeter-area ratios of suitable habitat, moderate suitable habitat, general suitable habitat, unsuitable habitat of the actual habitat were all greater than the potential habitat. The result showed that:the habitats of all of the four habitat suitable rank were fragmented in various degrees with the human disturbance effect. The mean shape index of suitable habitat, moderate suitable habitat, and general suitable habitat of the actual habitat were less than the potential habitat, but the mean shape index of unsuitable habitat of the actual habitat was greater than the potential habitat. The result showed that:as the result of the human disturbance effect, the shape of patch became simple, and the conditions of microhabitat became monotonous. The mean contiguity index of moderate suitable habitat, and general suitable habitat of the actual habitat was less than the potential habitat, but the mean contiguity index of suitable habitat, and unsuitable habitat of the actual habitat was greater than the potential habitat. The results showed that because of the human disturbance, the connectedness of moderate suitable habitat and general suitable habitat was descended, and the connectedness of suitable habitat and unsuitable habitat was increased. However, the connected- ness of suitable habitat of the actual habitat increased compared with the potential habitat based on the area of suitable habitat was decreased sharply.