Abstract

A develop a new environmentally friendly controlled-release urea to improve soil nitrogen supply capacity, wheat yield and nitrogen use efficiency, six coated urea were prepared in this study: resin-coated urea; phosphate rock powder-coated urea; phosphate rock powder and epoxy resin-coated urea; urease and nitrification inhibitors combined with epoxy resin-coated urea; urease and nitrification inhibitors combined with phosphate rock-coated urea; and urease and nitrification inhibitors combined with phosphate rock and epoxy resin-coated urea (RPHDU). Scanning electron microscopy and hydrostatic release tests were used to evaluate the microstructure and controlled-release properties of different urea. Using zero nitrogen treatment and conventional urea treatment as controls, six self-made coated urea were used for different fertilization treatments, with a total of eight treatments set up for ammonia volatilization test and field experiment to study the effects of different fertilization treatments on ammonia volatilization, soil nitrogen supply capacity, wheat yield, and nitrogen use efficiency. The results showed that the RPHDU coating had a complete and tight membrane shell. RPHDU had controlled-release periods for nitrogen, hydroquinone, and dicyandiamide (cumulative nutrient release > 80%) of 112, 56, and 28 days, respectively, effectively controlling the release of nutrients and inhibitors. The treatments of adding inhibitors delayed the ammonia volatilization peak and reduced the peak value, with the RPHDU treatment having the lowest cumulative ammonia volatilization. During the critical growth period of wheat, the soil available nitrogen content in the RPHDU treatment was higher than in other treatments, which brought soil nutrient supply closer to wheat demand. Moreover, the soil apparent nitrification rate was lower in the RPHDU treatment than in other treatments throughout the entire wheat growth cycle, reducing the risk of nitrate nitrogen leaching. The RPHDU treatment achieved the highest wheat yield and nitrogen use efficiency, which were significantly increased by 21 and 21%, respectively, compared to the U treatment. In summary, RPHDU could more effectively control nutrient release, improve soil nitrogen supply capacity, reduce soil nitrogen loss, and increase wheat yield and nitrogen use efficiency. The results of this study may provide a basis for the development of novel and environmentally friendly fertilizers.

中文翻译：

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磷矿粉、缓蚀剂和环氧树脂包膜增效尿素的制备及其对土壤供氮能力、小麦产量和氮素利用效率的影响

摘要

为了开发一种新型环保型控释尿素，以提高土壤供氮能力、小麦产量和氮素利用效率，本研究制备了六种包膜尿素：树脂包膜尿素；磷矿粉包衣尿素；磷矿粉和环氧树脂包覆尿素；脲酶和硝化抑制剂与环氧树脂包覆的尿素相结合；脲酶和硝化抑制剂与磷矿包衣尿素组合；以及脲酶和硝化抑制剂与磷矿和环氧树脂包覆尿素（RPHDU）的组合。采用扫描电子显微镜和静水压释放试验评价不同尿素的微观结构和控释性能。以零氮处理和常规尿素处理为对照，用6种自制包膜尿素进行不同施肥处理，共设置8个处理进行氨挥发试验和田间试验，研究不同施肥处理对氨挥发的影响、土壤氮素供应能力、小麦产量和氮素利用效率。结果表明，RPHDU涂层具有完整、致密的膜壳。 RPHDU对氮、对苯二酚和双氰胺（养分累积释放>80%）的控释期分别为112、56和28天，有效控制了养分和抑制剂的释放。添加抑制剂处理延迟了氨挥发峰值并降低了峰值，其中RPHDU处理的累积氨挥发量最低。在小麦关键生育期，RPHDU处理土壤速效氮含量高于其他处理，使土壤养分供应更接近小麦需求。此外，在整个小麦生长周期中，RPHDU处理的土壤表观硝化率低于其他处理，降低了硝态氮淋失的风险。 RPHDU处理的小麦产量和氮素利用效率最高，比U处理分别显着提高21%和21%。综上所述，RPHDU可以更有效地控制养分释放，提高土壤氮素供应能力，减少土壤氮素流失，提高小麦产量和氮素利用效率。本研究结果可为开发新型环保肥料提供依据。