流溪河流域菜地土壤磷素特征及流失风险分析

Vegetable plot soil phosphorus characteristics of Liuxi river and its environmental impact

通过化学分析、等温吸附试验对广州重要水源地流溪河流域的菜地土壤磷素特征和流失风险进行了研究分析。结果表明,流溪河流域菜地土壤全磷(P2O5)含量平均为0.24%,有效磷(P2O5)含量平均为95.14 mg/kg,分别为自然土壤的18.46倍和40.49倍,土壤磷素积累明显,已经远远超过作物需要;Lanmuir方程能够很好的表达流域内土壤磷素的吸附特征,由Lanmuir方程求得的相关参数可以作为土壤磷素流失风险和对水环境影响程度的评估依据。指出菜地土壤应该作为该流域内的农业非点源磷污染的重点控制区,在施肥方面应加以重视。

The characteristics and run - off risk of vegetable plot rail phosphorus in Liuxi river area was analysed by chemistry analysis and adsorption experiment. The result indicate that the total phosphorus（P2O5） average content is 0.24 % and availability phosphorus（P2O5） average content is 95.14 mg/kg, which is 18.46 and 40.49 times of nature soil. Phosphorus accumulate is distinct and far more than the needs of crops. Equality adsorption experiment indicate that it can express well by Langmuir equation the adsorbent characteristics of soil phosphorus in this aera. The related parameter can be the evaluate accordance of soil phosphorus run - off risk and environmental impact. The vegetable plot soll should be thought importance as critical source areas of phosphorus pollution.