关键词: 高原鼠兔, 裸斑恢复, 植被生产力, 土壤理化性质, 土壤退化指数

Abstract: Vegetation productivity and soil physicochemical properties are the basis for determining the structure and function of grasslands. In this study, we divided the disturbed area of plateau pikas into vegetated zone, plateau pika induced new bare patch, old bare patch, and abandoned bare patch. Based on the space-for-time substitution method, we investigated changes in aboveground biomass of different plant functional groups, total aboveground and underground biomass, and soil physicochemical properties, as well as soil degradation caused by plateau pika. The results showed that the aboveground biomass of sedges and grasses were highest in vegetated zone, while the aboveground biomass of forbs and legumes, and total aboveground and underground biomass of vegetation were relatively higher in vegetated zone and abandoned bare patch. There were no significant differences in soil water content, bulk density, total nitrogen, total phosphorus, ammonium, nitrate nitrogen, and pH among the four types of vegetation. However, soil total carbon and organic carbon were lowest in new bare patch, and had no difference among vegetated zone, old bare patch and abandoned bare patch. Soil total potassium was lowest in abandoned bare patch, and had no difference among vegetated zone, new bare patch and old bare patch. With the recovery, soil degradation index increased from new bare patch (-8.01%) to old bare patch (-3.41%), and then decreased to abandoned bare patch (-4.1%). It is suggested that when restoring the new and old bare patches, comprehensive reseeding of various functional group plants should be carried out. In the abandoned bare patches, the reseeding of grasses and the application of potassium fertilizer should be emphasized.

Key words: plateau pika, recovery of bare patch, vegetation productivity, soil physicochemical properties, soil degradation index