摘要
Alpine meadow is the predominant ecosystem in Qinghai-Tibet Plateau.The firm turf of alpine meadow formed by sub-surface anfractuous roots can be effective in conserving water and soil.Alpine meadow is a primary contributor to the Chinese Water Tower.For quantitative assess anti-erosion ability of alpine meadow,this paper selected three typical meadow slopes with>60% vegetation coverage to evaluate soil erosion rates using 137Cs.The results showed that(1)soil erosion intensity of typical alpine meadow was slight to light.Erosion rates were 464 t km–2 a–1 in Malong Village,415 t km–2 a–1 in Yeniugou Town and 875 t km–2 a–1 in Zhenqin Town respectively;(2)soil erosion rates were correlated negatively with vegetation coverage,and the relationship was clearer at the slope scale than plot scale;(3)the relationship between soil erosion and vegetation coverage showed that vegetation coverage was a predominant factor in retaining soil and water on slopes.With complete turf and high vegetation coverage, alpine meadow was of great significance for soil conservation and prevention of soil erosion.
Alpine meadow is the predominant ecosystem in Qinghai-Tibet Plateau. The firm turf of alpine meadow formed by sub-surface anfractuous roots can be effective in conserving water and soil. Alpine meadow is a primary contributor to the Chinese Water Tower. For quantitative assess anti-erosion ability of alpine meadow, this paper selected three typical meadow slopes with 〉60% vegetation coverage to evaluate soil erosion rates using 137Cs. The results showed that （1） soil erosion intensity of typical alpine meadow was slight to light. Erosion rates were 464 t km-2 a-1 in Malong Village, 415 t km-2 a-1 in Yeniugou Town and 875 t km-2 a-1 in Zhenqin Town respectively; （2） soil erosion rates were correlated negatively with vegetation coverage, and the relationship was clearer at the slope scale than plot scale; （3） the relationship between soil erosion and vegetation coverage showed that vegetation coverage was a predominant factor in retaining soil and water on slopes. With complete turf and high vegetation coverage, alpine meadow was of great significance for soil conservation and prevention of soil erosion.
基金
supported by the National Basic Research Program of China (2009CB421105)
Western Act Plan of the Chinese Academy of Sciences
the National Technology Support Project (2006BAC08B00)
