控释肥的物理-生化复合控释技术及其效果研究

Technology and Effect of Controlled-Release Fertilizer through Physical-Biochemical Composite Approaches

为突破采用单一技术手段生产控释肥的技术常规,探索物理-生化复合控释手段在包膜控释肥生产中应用的可行性,在包膜材料中加入具有脲酶抑制和硝化抑制功能的氨氧化木素AOL制得包膜尿素(PAU),以单一物理控释包膜尿素(PRU)为对照,对两者的控释性能、控释机理和肥效进行了比较研究。包膜尿素在水中溶出率的测定结果表明:PAU的水中初次溶出率和微分溶出率均高于PRU;2种包膜尿素在土壤中溶出的氮素转化动态变化试验结果显示,从膜中溶出的AOL对土壤中尿素的水解以及铵态氮的转化具有明显的抑制作用,表现为加入PAU的处理在培养期间土壤铵态氮和硝态氮所占比例较低。玉米盆栽试验结果显示,与普通尿素相比,供试2种包膜尿素处理均能显著提高作物生物量和当造氮肥利用率,PAU处理两造累积生物量较PRU处理提高15.35%,第1造氮肥利用率提高13.6个百分点。盆栽玉米收获后土壤残留矿质氮分析结果表明,PAU处理土壤残留矿质氮中铵态氮含量明显高于PRU处理,而硝态氮则明显低于PRU。物理-生化复合控释手段在包膜控释肥生产技术开发中的应用为提高产品控释性能、降低生产成本提供了一条新的技术途径。

For breaking the conventional simple approach to produce controlled-release fertilizer, the feasibility of physical-biochemical composite approaches used in manufacturing coated controlled-release fertilizer was studied. The controlled release characteristics, controlled release mechanism and fertilizer effect of coated urea PAU,with ammonium oxidization lignin（AOL） as coating material which could restrain both of urea and nitrification,was studied compared with coated urea PRU. The PAU＇s initial dissolution rate and the differential coefficient dissolution rate in water were higher than that of the PRU. The dynamic experiment on the change of the dissolved N translation in soil from the two coated urea showed that AOL dissolved from the coat obviously restrained the hydrolyzation of the urea and the translation of NH4^＋-N in soil. The NH4^＋-N and NO3^--N contents in soil with PAU were lower during cultivation. The pot experiment with maize showed that compared with common urea the two kinds of coated urea could promote the growth of the plants and raised the N use efficiency under equate N condition. The total biomass of two crops of maize with PAU increased by 15.35% compared with PRU,and the N use efficiency of the first crop raised by 13.6%. Analysis of remained mineralized N in soil after reaping the maize showed that the NH4^＋-N in soil remained mineralized N with PAU was much higher than that with PRU, and the NO3^--N was reverse. It was a new technical approach to improve controlled effect and reduce costs of operation that the physical and biochemical approaches used in producing coated controlled-release fertilizer.