红壤小流域不同利用方式土壤钾素流失特征研究

A Study on Principle of Potassium Loss Under Different Land Use Patterns in Red Soil Watershed

从资源利用的角度研究了红壤小流域不同利用方式土壤钾素的流失特征,结果表明,植被覆盖度低,无水保措施的试验区钾素流失量最大,封山育林,恢复保护性植被的试验区的钾素流失量最低。在农林利用的试验区中,粗放经营的试验区的钾素流失量大于水土保持综合性农林措施的试验区。土壤钾素流失时间主要集中在5月份和6月份梅雨季节和8月份台风雨季节,其流失量约占全年流失量90%以上,钾素的流失形态主要为泥砂结合态,约占全钾流失量94%以上,影响钾素流失的主要因素为降雨量、降雨侵蚀力、径流量和泥砂流失量。

From the view of natural resource utilization and protection, a study on the principle of potassium loss under different land use patterns in a red soil watershed was conducted in Zhejiang province of southern China. The results showed that K loss in a catchment with less vegetation cover and nonsoil conserving practices was highest, while lowest K loss occurred in catchment with vegetation conservation. K loss in an extensive farming catchment was higher than that of catchment in which comprehensive measurements for conservation were practiced. K loss was concentrated in the plum rainy season (May and June) and the typhoon rainy season (August), accounting for more than 90% of the total K loss. K was lost mainly in a particular form, accounting for more than 94% of the total K loss. The factors impacting on K loss were precipitation, rainfall erosion index, runoff and sediment.