有机养分替代对小麦产量、土壤肥力及麦田氮磷径流流失的影响

为探讨不同有机肥替代率对小麦减肥增效及减少麦田氮磷流失的效果,在等氮有机养分替代条件下进行田间小区监测试验,设置8种不同处理,分别为空白对照(CK),常规施肥(CF),100%、50%、30%猪粪有机养分替代氮肥(M1、M2、M3)及100%、50%、30%秸秆有机养分替代氮肥(F1、F2、F3),研究有机肥替代率对小麦产量、麦田氮磷流失、肥料利用率和土壤肥力的影响。结果表明,100%有机养分替代处理与常规施肥处理相比小麦产量均显著降低,但减少了麦田氮径流流失,提高了土壤肥力。麦田不同处理下总氮流失量为21.90~33.66 kg·hm^-2,与常规施肥处理相比,不同比例猪粪、秸秆有机养分替代处理总氮流失量减少了8.44%~25.94%;总磷流失量为0.60~2.00 kg·hm^-2,100%有机养分替代处理相比于常规处理总磷流失量升高了24.64%~44.93%。不同处理下小麦氮、磷肥利用率分别为17%~35%、5%~19%,其中30%~50%猪粪有机养分替代处理下氮、磷肥利用率较高,而100%猪粪、秸秆有机养分替代氮、磷肥利用率较常规施肥处理均显著降低。有机养分替代能够缓解土壤酸化,使土壤pH值维持稳定,与常规施肥处理相比,有机养分替代处理下土壤肥力有所提高。综合不同比例猪粪、秸秆有机养分替代对小麦产量、土壤肥力及麦田氮磷径流流失的影响,30%~50%猪粪有机养分替代在保证小麦高产稳产的同时,能有效降低麦田氮径流流失量,且维持较低水平磷径流流失量,是一种适宜的资源有效利用、节肥增效的有机养分替代模式。本研究结果为小麦生产中合理利用养分资源、减少化肥投入、控制麦田氮磷径流流失提供了参考。

Effects of Organic Nutrient Replacement on Wheat Yield,Soil Fertility and Runoff Loss of Nitrogen and Phosphorus in Wheat Field

A field plot experiment was conducted under the conditions of the same nitrogen and organic nutrients replacements to explore the effect of different organic fertilizer replacement rates on reducing fertilizer and increasing benefits of wheat, reducing loss of nitrogen and phosphorus in wheat field. Eight different treatments were set up with blank control (CK), conventional fertilization (CF), 100%, 50%, 30% pig manure organic nutrients replacing nitrogen fertilizers (M1, M2, M3) and 100%, 50%, 30% straw organic nutrients replacing nitrogen fertilizers (F1, F2, F3). This paper studied the effects of different organic fertilizer replacement rates on wheat yield, loss of nitrogen and phosphorus in wheat field, fertilizer utilization and soil fertility. The results showed that 100% organic nutrients replacements treatments significantly decreased wheat yield, but it helped reduce the nitrogen runoff loss and improve soil fertility compared with the conventional fertilization treatment. Under different treatments, the losses of total nitrogen (TN) in wheat fields were 21.90~33.66 kg·hm^-2, and that of total phosphorus (TP) were 0.60~2.00 kg·hm^-2. Compared with conventional fertilization treatment, the losses of TN reduced by 8.44%~25.94% under different proportions of pig manure and straw organic nutrients replacements treatments, and the losses of TP increased by 24.64%~44.93% under 100% organic nutrients replacements treatments. Under different treatments, the utilization rates of N and P fertilizers in wheat were 17%~35% and 5%~19%, respectively. They were higher under 30%~50% pig manure organic nutrients replacements treatments. However, the utilization rates of N and P fertilizers all decreased significantly under 100% pig manure and straw organic nutrients replacements treatments. Organic nutrients replacements could alleviate soil acidification and keep soil pH stable, and improve soil fertility compared with conventional fertilization treatment. Considering the effects of different proportions of pig manure and straw organic nutrients replacements on wheat yield, soil fertility and runoff losses of nitrogen and phosphorus in wheat fields, 30%~50% of pig manure organic nutrients replacements could ensure high and stable yield, reduce the runoff losses of nitrogen effectively, and keep the runoff losses of phosphorus at a lower level in wheat fields. Thus, they are the optimal modes of organic nutrients replacements for efficient utilization of resources, saving fertilizers and increasing efficiency. This study provided a reference for rational utilization of nutrients resources, reducing fertilizers inputs, and controlling the runoff losses of nitrogen and phosphorus in wheat fields.