新疆北疆绿洲麦豆轮作周年氮肥减施增效调控机理研究

Accompany with the climate warming in Xinjiang, there has been a rapid development of wheat-bean system in northern Xinjiang. While farmers still keep their original method of fertilizing wheat and soybeans separately in the production of multiple cropping. Furthermore, to pursue high yield of soybean, they even do excessive fertilization without considering the fertilizer consumption relationship between preceding and succeeding crop, which not only increase costs and soil nitrogen load, but also lead to some issues such as low nitrogen utilization, poor yield, environment pollution etc. For this reason, a practical technical solution for the rational fertilizing of local wheat and soybean in the two crops system is urgently required to realize the fertilizer reduction, synergism and high yield of soybean. The research object of this subject will be two pieces of mature wheat and soybean fields in northern Xinjiang. The objective is to improve the nitrogen fertilizer utilization and soybean yield on a yearly basis. The research will be carried out from both field experiment and laboratory analysis. The statistics will be developed to verify the effects of various nitrogen fertilizer combination treatment on soil nitrogen accumulation migration, soil microflora, soil microbial biomass and soybean growth and development regularity, and revealed the relationship among them. By studying and better understanding of the relationship and control methodology among nitrogen fertilizer reduction, synergism and soybean yield. It provides theoretical evidence and technical support for the nitrogen control techniques on nitrogen application reduction and synergistic of two mature of wheat and bean in northern Xinjiang. It would benefit the further discovery and sustainable development of high yield and high efficiency of other similar multiple cropping in northern Xinjiang.

随着新疆气候不断变暖，北疆麦豆两熟种植发展迅速，但多熟种植中农户仍按照以往单作的施肥习惯，对小麦和大豆分别施肥，更甚为了追求大豆高产未考虑上下茬口耗肥关系而过量施肥，导致出现成本增加、氮肥利用率低、大豆产量不理想、环境污染等问题。为此，迫切需要探索出一套适宜于麦豆两茬作物合理施肥的技术体系，以实现多熟种植周年氮肥减施增效大豆高产的目的。本课题以北疆麦豆两熟农田为研究对象，以减施氮肥、提高周年氮肥利用率和大豆高产为目标，采取田间试验和实验室分析相结合的研究方法，研究多熟种植麦豆两茬作物不同施氮量组合对土壤氮素累积运移、土壤微生物氮素生理群、土壤微生物生物量以及大豆生长发育规律等的影响及其相互关系。通过研究明确多熟种植氮肥减施与大豆高产的关系及其调控机理，从而为提出北疆多熟种植系统氮肥减施增效的氮肥调控技术提供理论依据，为北疆发展其它多熟种植高产高效模式的可持续发展做出有益的探索。

随着新疆气候不断变暖，北疆麦豆两熟种植发展迅速，但多熟种植中农户周年氮肥施用不合理，更甚为了追求大豆高产未考虑上下茬口耗肥关系而过量施肥，导致出现成本增加、氮肥利用率低、大豆产量不理想、环境污染等问题。为此，本课题以北疆麦豆两熟农田为研究对象，以减施氮肥、提高周年氮肥利用率和大豆高产为目标，采取田间试验和实验室分析相结合的研究方法，开展麦豆两熟周年施氮量组合对土壤氮素累积运移规律、农田土壤微生物区系、复播大豆产量形成的影响及相关关系研究。.通过研究揭示了小麦复播大豆周年氮肥施用组合条件下，农田土壤养分、氮素累积运移及形态变化规律及土壤三大微生物种群数量和种群结构的变化规律。在周年施氮的条件下，前后茬施氮越高，土壤氮素的累积效应随之增强，其中麦季施氮173kg/hm2、豆季施氮138kg/hm2的周年施氮组合的土壤养分含量和酶活性基本表现最优，而豆季施氮138kg/hm2的前提下，麦季施氮量为173-242 kg/hm2时更有利于土壤微生物数量的增殖和菌群结构的优化。明确了多熟农田土壤养分、微生物数量、酶活性与产量之间具有密切的相关关系，通过施氮直接改变土壤养分状况进而影响土壤微生物数量和酶活性，土壤微生物改善土壤质量，促进作物根系对土壤养分的吸收利用，最终影响到作物的生长发育及产量形成。在本研究条件下，前茬小麦季施氮水平达到173kg/hm2，夏大豆当季在始花期施氮肥69kg/hm2时，三年大豆产量最高平均达到3013.24kg/hm2，麦-豆周年总产量亦最大，三年平均为10798.48kg/hm2，氮肥利用效率高，有利于促进小麦−大豆周年轮作体系的高效生产。. 通过本项目的研究，先后在植物营养与肥料学报、生态学杂志、南京农业大学学报、核农学报等学术期刊发表论文17篇，发布地方标准1项，培养硕士研究生5名。