环大冶湖区域土壤磷素水平及流失风险分析

Phosphorus Level of Soil and Loss Risk Assessment in the Area Around Daye Lake

该文在环大冶湖区域内采集42个土样,在实验室分析总磷(TP)、土壤有效磷(Olsen-P)、易解吸磷(CaCl_(2)-P)、藻类有效磷(NaOH-P)含量,收集相关文献研究成果并对比分析,以了解环大冶湖区域4种典型利用方式下土壤磷素形态含量特征,对其流失风险进行了分析。结果表明:(1)各类土壤磷含量变化范围较大,TP含为175.56~1232.70 mg/kg,平均值为653.0 mg/kg;Olsen-P含为1.24~63.72 mg/kg,平均值为10.24 mg/kg;CaCl_(2)-P含量为0.14~11.72 mg/kg,平均值为1.84 mg/kg;NaOH-P含量为20.23~279.56 mg/kg,平均值为96.98 mg/kg;(2)以Olsen-P含量为横坐标,以CaCl_(2)-P含量为纵坐标,采用双线性模型模拟土壤磷素淋失“突变点”,但并未出现明显的“拐点”。TP和NaOH-P水平呈现蔬菜地>水稻田>旱地>林地;Olsen-P和CaCl_(2)-P水平呈现蔬菜地>林地>旱地>水稻田;4种典型利用方式下土壤磷素积累水平普遍不高,磷素流失风险较低。

42 soil samples were collected in the area around Daye Lake and analyzed in the laboratory for TP,Olsen-P,CaCl_(2)-P and NaOH-P content,then the obtained data were compared and analyzed with the related literature,in order to study the soil phosphorus content characteristics and analyze the loss risk under different land utilizations.The results indicated that there was significant difference in the content of soil phosphorus under different land utilization.The content of TP was175.56~1232.70 mg/kg,and the average value was 653.0 mg/kg,the content of Olsen-P was 1.24~63.72 mg/kg,and the average value was 10.24 mg/kg,the content of CaCl_(2)-P was 0.14~11.72 mg/kg,and the average value was 1.84 mg/kg,and the content of NaOH-P was 20.23~279.56 mg/kg,and the average value was 96.98 mg/kg.Using the content of Olsen-P as abscissa and the content of CaCl_(2)-P as ordinate,the bilinear model was used to simulate the change-point of phosphorus leaching,but the inflection point did not appear.The order of TP and NaOH-P content is as vegetable soil>paddy field>the other dry lands>woodland,the order of Olsen-P and CaCl_(2)-P content is as vegetable soil>woodland>the other dry lands>paddy field.The accumulation of the soil phosphorus under the four typical land utilization is little in the area around Daye Lake and the risk of loss is lower.