不同雨强和坡度条件下紫色土养分流失规律研究

Research on the nutrient loss from purple soil under differentrainfall intensities and slopes

采用室内模拟降雨装置,研究了三峡库区紫色土在不同雨强和坡度条件下的养分流失规律。结果表明,紫色土坡面流失养分主要由径流和泥沙携带,其中径流养分含量与雨强和坡度无关,但与产流过程一致。泥沙中养分含量与雨强无关,但随坡度增加而降低;泥沙养分含量与产沙量过程无关,但其流失量与产沙量过程一致。泥沙中各养分含量略大于降雨前表土养分含量,远大于径流养分含量,但由于径流中以速效养分为主,故径流携带的养分流失量不容忽视。

With simulated rainfall equipment, the pattern of soil nutrients from purple soil under different rainfall intensities and slopes was studied Results showed that the majority of soil nutrients was removed with runoff and sediment The content of nutrients in the runoff was not interrelated with rainfall intensity and slope, but with the amount of runoff The content of nutrients in the sediment was not interrelated with the rainfall intensities There was negative correlation between the slope and the content of nutrients in the sediment The nutrient loss was in direct proportion to the amount of sediment and runoff The content of nutrients in the sediment was slightly higher than that in the surface soil before rainfall, but exceedingly higher than that in the runoff Because the nutrients in the runoff mainly consisted of available ones, the nutrient loss via runoff could not be neglected