关键词: 森林土壤, 外源碘, 富碘山野菜

Abstract: Marco Polo sheep (Ovis ammon polii) is an endemic species and also a flagship species of Pamir Plateau. Assessment of habitat suitability is the prerequisite and basis for the effective conservation of this species. From May to November 2017, 104 occurrence points of Marco Polo sheep were confirmed by using the line transect method. Combining 27 kinds of environmental variable factors, the MaxEnt model was used to determine the main factors affecting the distribution of Marco Polo sheep, and to assess its potentially suitable habitat in Taxkorgan Wildlife Nature Reserve. The results showed that the AUC (area under ROC curve) value was 0.955, suggesting perfect predictive effect of the model. Suitable habitat of Marco Polo sheep was mainly distributed in the northwest part of the reserve. The area of suitable habitat was around 1288.53 km², which only accounted for 8.12% of the total area. Altitude, temperature seasonality, vegetation type, mean temperature of wettest quarter, lowest temperature of coldest month, and slope were the most important environmental factors affecting the suitable habitat distribution of Marco Polo sheep, whereas human disturbance and land use had less influence. The suitable vegetation types of Marco Polo sheep were mainly desert and grassland, and the range of altitude was 3500-4800 m. We proposed two strategies on the conservation and management measures of Marco Polo sheep population: Controlling human disturbance and establishing a migration corridor among suitable habitats.

Key words: Forest soil, Exogenous iodine, Iodine-enriched wild vegetables