滇池湖滨韭菜地磷污染特征调查

该文选择了昆明市滇池北岸福保村的韭菜地进行灌溉周期及土壤/水中磷的空间分布的调研,分析了福保村韭菜地磷污染的特征。结果表明,福保村韭菜地排水边沟中总磷浓度和韭菜地的灌溉周期密切相关,灌溉来水日总磷浓度为0.53mg/L,直到下个灌溉周期到来前总磷浓度持续下降,逐渐降至0.21mg/L。韭菜地排水控制在灌溉周期的后期,将大大减少磷所产生的面源污染。随着土壤深度的增加,土壤渗滤水中正磷酸盐浓度逐渐降低。韭菜地中土壤可利用性磷含量随着深度的增加而减少,而土壤水溶性磷则保持一定水平。此研究结果将为韭菜地非点源污染的有效控制提供基础数据。

Investigation of Phosphorus Pollution in Leek Field at Lakeside of Dianchi Lake

Irrigation cycle and spatial distribution of phosphorus concentration in soil/water were made in leek field of Fubaocun Village of Dianchi valley. Phosphorus pollution characteristic in leek field at Fubaocun Village was analyzed. The results showed that the total phosphorus concentration had close relation with the irrigation interval of leek field. The phosphorus concentration was highest in the first irrigation date, which was 0.53 mg/L, and then it declined continuously to the minimum concentration, which is 0.22 mg/L, until the last irrigation date in one irrigation cycle. The phosphorus discharge from leek field will be decrease significant if the wastewater discharge was controlled at the anaphase of the irrigation cycle. The orthophosphate concentration of the infiltration water of soil and the available phosphorus concentration in soil decreased with the increase of the soil depth. But the soluble phosphorus was stable within the studied soil depth. This conclusion will provide some basic data for the control of nonpoint source phosphorus pollution from leek field.