秸秆培肥土壤对优先流中养分淋失的影响

为了研究秸秆培肥土壤后对优先流中养分淋失的影响,采用原状土柱模拟养分淋溶的方法,对秸秆培肥后土壤中养分淋失的状况进行了研究。结果表明,土壤经秸秆培肥后,淋溶液中氮、磷和钾的累计含量降低,淋失速度和含量也都有不同程度的降低,但对不同养分降低的效果不同,对阳离子养分的保持效果更好一些,未施秸秆处理的NH4+-N累计含量为秸秆培肥处理的4.54倍;而对硝态氮的保持作用最差,未施秸秆处理的NO3--N累计含量为秸秆培肥处理的2.79倍。说明秸秆培肥土壤对减少养分淋失和降低地下水污染具有一定作用。

Effects of soil cornstalk fertilization on nutrient leaching in preferential flow

In order to find the effect of soil cornstalk fertilization on nutrient leaching in preferential flow,nutrient leaching experiment was designed with soil column in size of 0.8 m in depth and 0.15 m in diameter.The results indicated that applying cornstalk into soil had a better effect on decreasing the nutrient leaching.Soil cornstalk fertilization delayed the speed of nutrient leaching,so decreased the amount of leaching water that was only one third of the soil without cornstalk fertilization.The concentration of the leaching water decreased after cornstalk fertilization,and the decreasing of different nutrients varied:NH 4-N>K >PO-4>NO-3,but before the end of the leaching experiment,the concentration of leaching water in cornstalk fertilization soil was a little higher than the leaching water of the soil without the application of cornstalk.Thus,soil fertilizing with cornstalk was an effective method for reducing nutrient leaching and the pollution of underground water through decreasing the speed and nutrient concentration in preferential flow.