秸秆沟埋还田背景下丛枝菌根真菌对麦田土壤氧化亚氮排放的影响

摘要：农田生态系统作为重要温室气体N₂O最大的人为排放源，近年来成为研究者关注的焦点。秸秆沟埋还田是否能通过促进丛枝菌根真菌及其菌丝际微生物的生长与活性，从而降低氮素循环反应中的底物浓度，进而降低N₂O排放，这一机理还有待验证。本研究通过设计栽培管控制试验，探讨了在秸秆沟埋还田背景下，不同土壤中作物与土壤丛枝菌根真菌互作的根际效应与菌根效应。结果表明：在秸秆沟埋还田技术背景下，土壤粘密使得根际效应更为显著，而在土壤通气性好的砂土中，菌根效应更为显著；粘土土壤中作物根际净效应促进土壤中硝化作用的进行，进而增加了N2O排放；砂土土壤中菌根效应促进对土壤有效氮素的固持而降低氮素循环反应中的底物浓度，进而降低N₂O排放。34925
毕业论文关键词：秸秆还田；丛枝菌根真菌；氧化亚氮；球囊霉素
Effects of Arbuscular Mycorrhizal Fungi on N2O emissions from soil in wheat field under the background of straw ditch buried returning
Abstract： Farmland ecosystems have become the focus of attention of researchers in recent years as the largest anthropogenic source of N2O, an important greenhouse gas. Whether the straw ditch can improve the growth and activity of arbuscular mycorrhizal fungi and mycelial microbes, thereby reducing the concentration of substrate in the nitrogen cycle reaction and thus reducing the N₂O emission, this mechanism needs to be verified. In this study, the rhizosphere effect and mycorrhizal effect of interaction between crops and soil arbuscular mycorrhizal fungi in different soils were discussed under the background of straw ditch restoration. The results showed that the rhizosphere effect was more significant under the background of straw mulching, and the effect of mycorrhizal effect was more significant in soil with good soil permeability. The net effect of crop rhizosphere in clay soil And promote the nitrification in the soil, and then increase the N2O emission. The moss in the sand soil promoted the fixation of the available nitrogen in the soil and decreased the concentration of the substrate in the nitrogen cycle reaction, thus reducing the N₂O emission.
Key words: Straw ditch buried returning；AMF；N2O；GRSP
目录

摘要1
关键词1
Abstract1
Key words1
引言1
1 材料与方法3
1.1 试验设计3
1.2 处理方法 4
1.2.1 植株4
1.2.2 土壤4
1.2.3 气体5
1.3 统计方法5
2 结果6
2.1 作物生长状况6
2.2 球囊霉素活性与丛枝菌根真菌侵染率7
2.3 土壤氮素与N2O排放8
3 讨论10
4 结论12
致谢12
参考文献13
附录栽培管及取气装置模拟图15
秸秆沟埋还田背景下丛枝菌根真菌对麦田土壤氧化亚氮排放的影响
氧化亚氮（N₂O）是一种重要的温室气体及大气平流层臭氧破坏者，其增温潜能约是CO2约300 倍[1].据统计,农田生态系统是N₂O最大的人为排放源，全球大约2/3的人为N₂O排放来自于农耕土壤[2]。根据Nosalewicz M等人的研究,农田生态中的栽培条件（水肥运筹、耕作方式）和环境条件（土壤水分、温度及酸碱度等）均会对系统中的N₂O的排放产生影响[3-6]。在我国，秸秆还田是一种大范围推广且卓有成效的农业废弃物处理措施，其具有重要的生态功能，在增强土壤碳汇、改善土壤结构、促进养分循环及降低环境污染等方面有重要的作用[7]。关于秸秆还田是否能有效减少土壤氧化亚氮的排放，结论及影响机制仍未明确，但根据不断的深入研究，秸秆还田土壤N₂O排放的强度和特点受具体还田方式及农田生态系统类型的影响，且在秸秆沟埋的前提下可以有效降低N2O排放达30%[8-10]。因此，研究秸秆沟埋还田技术下农田土壤N₂O排放机制对调控农业生产减排具有重要理论和实践指导意义。秸秆沟埋还田背景下丛枝菌根真菌对麦田土壤氧化亚氮排放的影响:http://www.751com.cn/shengwu/lunwen_32646.html