我省氮化肥用量增长很快,但不少地方反映滥施氮化肥,养分效益下降。因此考察不同地区的氮化肥效益,对于指导我省化肥的生产、分配和施用,很有必要。通过田间试验,评价施氮的效果是基本的必不可少的方法,但就其结果所表示的广泛性、综合性:和连续性,则往往受时间、地点和 The amount of nitrogen fertilizer in our province increased rapidly, but in many places, excessive use of nitrogen fertilizer was reported, and the benefit of nutrients decreased. Therefore, investigating the benefits of nitrogen fertilizer in different regions, it is necessary to guide the production, distribution and application of fertilizer in our province. Evaluating the effectiveness of nitrogen application through field trials is an essential and indispensable method, but the breadth, generality and continuity in terms of its results are often affected by time, place and