太湖湖滨防护林营建对土壤养分动态的影响

Effect of Protection Forests Construction on Soil Nutrient Dynamics in Taihu Lake Basin

为了探讨太湖湖滨防护林建设对土壤养分动态变化的影响,在江苏宜兴市进行了环太湖防护林营建试验,分析了防护林建设前后土壤有机质、全氮、全磷、有效磷、全钾及有效钾的动态变化特征。结果表明：通过防护林建设能有效降低土壤中营养元素的含量,与农田土壤相比,防护林土壤的有机质和有效钾含量降低率分别为29.06%和26.33%,全氮、全磷和有效磷的降低率均超过30%。同时,防护林能够实现减源增汇的效果,通过减源和增汇合计,2009年10月—2011年5月,生态恢复区土壤的纯氮和纯磷负荷减少分别约46.30-69.54 g/m2和3.78-7.30 g/m2。可见,在太湖湖滨营建防护林能够起到治理面源污染、改善水质的作用。

In order to study the effect of protection forests construction on soil nutrient dynamics in Taihu LakeBasin, the experiment was implemented in Yixing City to study the changes of soil organic matter, totalnitrogen, total phosphorus, available phosphorus, total potassium and available potassium. The results showedthat the protection forests construction could effectively reduce the content of soil nutrients, compared withfarmland soil, the reduction rates of organic matter and available potassium content of forested soil were29.06% and 26.33%, the reduction rates of total nitrogen, total phosphorus and available phosphorus were allover 30%. Hence the research implied that protection forests construction could achieve the effect of sourcereduction and sink increasing for none-source pollutants, and through source reduction and sink increasing intotal, from October 2009 to May 2011, the ecological restoration area of pure nitrogen and pure phosphorusload reduction reached about 46.30-69.54 g/m2 and 3.78-7.30 g/m2.