Abstract: Taking the temperate steppe under four vegetation types around the Qinghai Lake of Northwest China as test objects, this paper studied the distribution patterns of soil nutrient heterogeneity under natural condition and grazing disturbance. There existed obvious layering characteristics in the soil available N, P, and K, being the highest in surface layer (0-10 cm) and decreased with soil depth. In degraded Stipa purpurea steppe, the available nutrient contents in different soil layers were lower than those in Poe steppe, Elymus nutans steppe, and Leymus secalinus steppe. The Poe steppe which was restored for a longer time and experienced exotic substance input had higher contents of soil available nutrients. The soil total N content in degraded S. purpurea steppe and E. nutans steppe was higher in 0-20 cm layer, but decreased sharply below 20 cm depth. In contrast, both Poe steppe and L. secalinus steppe showed a higher soil total N content at each depth. The soil total P content had no significant correlation with soil depth (P>0.05), but was significantly lower at the depths 0-10 cm, 10-20 cm, 20-30 cm, and 30-40 cm in degraded S. purpurea steppe than in other three steppes (P<0.05). The soil total K and organic matter contents in degraded S. purpurea steppe  were also lower than those in other three steppes. Soil organic matter content had significant correlations with soil total and available N, P, and K (P<0.01). Soil bulk density increased with soil depth. Degradation resulted in the increase of soil pH value. After 6 years recovery of degraded temperate steppes, the soil could be basically recovered. It was suggested that both grazing disturbance and natural factors could affect the soil nutrient status in temperate steppe.

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