不同磷水平处理下水稻田磷氮径流流失研究

研究了不同磷水平处理下水稻田磷素及氮素的径流损失情况。结果表明,不同磷水平处理下稻田径流水中磷素的浓度随着施磷量的增加而显著增加,磷的径流损失量呈现相同趋势,在每公顷施磷量为0 kg、25 kg6、0 kg1、20 kg及240 kg的情况下,磷的当季径流损失量分别达到了125 g/hm^2、499 g/hm^2、939 g/hm^2、3 022 g/hm^2及5 974 g/hm^2。试验结果还表明,施氮肥后短期内若出现径流则氮素流失较多,但不同磷水平处理对于稻田径流水中氮素的浓度及损失量没有影响。几次径流中活性磷的浓度均有诱发附近水域水体富营养化的可能。

Effects of Different P Fertilizer Application Rates on Soil Nitrogen and Phosphorus Losses with Surface Runoff during Rice Season

Experiment on effects of different P fertilizer application rates on soil nitrogen and phosphorus losses with surface runoff during rice season was done. The results showed that the concentration of P in runoff water was increasing with the application rates of P fertilizer thus leading a same trend of the quantities of P loss with runoff. The quantities of P loss with runoff were 125 g/hm^2 ,499 g/hm^2,939 g/hm^2,3 022 g/hm^2 and 5 974 g/hm^2 when the soil were fertilized as 0 kg/hm^2,25 kg/ hm^2 ,60 kg/hm^2,120 kg/hm^2 and 240 kg/hm^2 respectively. There was no difference in the nitrogen losses among the P application rates. Maybe it was dangerous to the water near the field.