不同还田模式下黄土高原旱作农田秸秆腐解特征及养分释放规律研究

发布时间：2018-06-25 21:20

本文选题：作物秸秆 + 腐解特征　；参考：《甘肃农业大学》2015年硕士论文

【摘要】：作物秸秆是一种重要的可再生有机资源,还田后对培肥地力、提高作物产量、保护生态环境等方面都具有重要作用,目前已成为最直接、有效的利用途径。在甘肃省定西市安定区李家堡镇麻子川村的甘肃农业大学旱农试验站,以黄土高原旱作农业区典型的旱作农田秸秆(玉米、小麦秸秆)为研究对象,采用尼龙网袋埋土法,研究了不同还田模式下秸秆的具体腐解情况及其养分释放规律,探讨了不同秸秆种类、耕作措施、添加量、还田深度、腐解剂等因素对秸秆腐解的影响,为该区合理利用秸秆、科学管理农田养分提供理论依据,也为在该区推广秸秆还田提供技术支撑。主要研究结果如下:1、在快速腐解期(100d)内,玉米秸秆比小麦秸秆腐解快,玉米秸秆中碳、氮、钾的释放也比小麦秸秆快,而两种秸秆磷素的释放率相差不大。2、地膜覆盖有利于秸秆腐解,养分释放率随时间延长而增加,不同养分释放率不一样。3、秸秆添加量对质量减失率没有显著影响,而腐解速率均随着秸秆添加量的增加而提高。秸秆养分释放率随时间延长而增加,但不同添加量下秸秆各养分释放率均相差不大。4、玉米秸秆土埋处理比表面覆盖腐解快,秸秆的养分释放率也表现为土埋还田大于覆盖还田。传统耕作下(T)还田深度为10cm的处理腐解最快;传统耕作结合地膜覆盖(TP)下,前期秸秆质量减失率、养分释放率均随还田深度的增加而增加;至腐解后期还田深度10cm与20cm的差异不明显,对秸秆腐解的影响不大。5、传统耕作下(T),三种腐解剂均能促进前期秸秆的腐解;传统耕作结合地膜覆盖下(TP),添加腐解剂对秸秆腐解没有明显效果。
[Abstract]:Crop straw is an important renewable organic resource. It plays an important role in increasing soil fertility, increasing crop yield and protecting ecological environment after returning to the field. It has become the most direct and effective way to use it. In the dry agriculture experiment station of Gansu Agricultural University in Lijiazibao Town, Anding District, Gansu Province, the typical dry cropland straw (corn, wheat straw) in the dry farming area of the Loess Plateau was used as the research object, and the Nilong net bag was used to bury the soil. The effects of different kinds of straw, tillage measures, adding amount, returning depth and decomposing agent on the decomposition of straw were studied in this paper. Scientific management of farmland nutrients provides theoretical basis, but also provides technical support for the promotion of straw returning to the field in this area. The main results were as follows: during the rapid decomposition period (100 d), corn straw decomposed faster than wheat straw, and the release of carbon, nitrogen and potassium from corn straw was also faster than that from wheat straw. However, the difference of phosphorus release rate between the two kinds of straw was not significant. The mulching of mulch was beneficial to the decomposition of straw. The nutrient release rate increased with time, and the release rate of different nutrients was different. The amount of straw added had no significant effect on the mass loss reduction rate. However, the decomposition rate increased with the increase of straw content. The nutrient release rate of straw increased with time, but there was no significant difference in nutrient release rate of straw with different adding amount. The decomposition rate of corn straw soil was faster than that of surface mulching, and the nutrient release rate of straw was higher than that of mulching. Under traditional tillage (T), the decomposition rate of 10cm was the fastest, and under the condition of traditional tillage and plastic film mulching (TP), the loss rate of straw mass and nutrient release rate increased with the increase of returning depth. There was no significant difference between 10cm and 20cm in the depth of straw decomposing at the later stage of decomposing, and the effect on the decomposition of straw was not significant. 5. Under traditional tillage, the three kinds of decomposing agents could promote the decomposition of straw in the early stage. Traditional tillage combined with plastic film mulching (TP) had no obvious effect on straw decomposition by adding decomposing agent.
【学位授予单位】：甘肃农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S141.4

【参考文献】