农田氮肥的流失对农民来说是一个经济问题。如氮素大量流失,还可能引起水污染。 Pa.Park大学东北流域研究中心的土壤科学家PonaldR.Schnabel试验了一种可以测定农田由于淋溶而引起氮(氨或硝酸盐)大量流失的简易新方法。因下雨而导致硝酸盐流失是化肥浪费的主要原因。这种新方法也许可用来确定;是否可以计划施肥,使硝酸盐这种重要氮源的流失降到最低限度。 Schnabel的测定技术是利用一个涂满一种离子换树脂(带正电或负电的聚苯乙烯 The loss of farmland nitrogen fertilizer is an economic problem for farmers. Such as a large loss of nitrogen, but also may cause water pollution. Ponald R. Schnabel, a soil scientist at the Parskin Northeastern Basin Research Center, tests a new and simpler method for determining the amount of nitrogen (ammonia or nitrate) that is drained from farmland due to leaching. Nitrate loss due to rain is the main reason for the waste of fertilizers. This new method may be used to determine whether fertilization can be planned to minimize the loss of nitrate, an important source of nitrogen. Schnabel’s measurement technique uses a coating of an ion-exchange resin (positively or negatively charged polystyrene