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秸秆沟埋还田对稻田产甲烷菌群功能的影响

时间:2018-08-26 20:06来源:毕业论文
DB-SR 能够改变稻田碳氮循环过程。然而,DB-SR 是否影响稻田产甲烷菌群功能,目前并不清楚。本论文通过恒温培养测定不同还田条件下稻田产甲烷菌群的 CH4产生能力以及 H2/CO2还原途径和

摘要:秸秆沟埋还田 (Ditch-buried straw return, DB-SR) 是一种新型土壤耕作措施。前期研究发现,DB-SR 能够改变稻田碳氮循环过程。然而,DB-SR 是否影响稻田产甲烷菌群功能,目前并不清楚。本论文通过恒温培养测定不同还田条件下稻田产甲烷菌群的 CH4产生能力以及 H2/CO2还原途径和CH3COOH 氧化途径的相对贡献率,研究秸秆沟埋还田对产甲烷菌群功能的影响,以期揭示 DB-SR对稻田 CH4排放的调控机制。 分别设置 3 个单因子实验, 包括沟埋深度 (CK、 20 cm、 30 cm 和 40 cm)、还田量 (CK、半量、全量和倍量) 以及还田方式 (CK、常规粉碎旋耕沟埋、机械沟埋和人工沟埋)。发现:表层 0-10 cm 的土样,沟埋深度为 30 cm 的 CH4产生能力最弱,其乙酸氧化途径的相对贡献率最小;在不同的沟埋量下,全量还田的 CH4产生能力高于其他处理,倍量还田的 H2/CO2还原途径的相对贡献率最大;在不同的还田方式下,常规粉粹旋耕还田的产甲烷菌总产量 CH4产生能力要低于其他处理,且其 CH3COOH 氧化途径的相对贡献率最小。综上所述,当全量沟埋深度为 30 cm 时产甲烷菌群的 CH4产生能力最弱,表明此还田技术能够有效控制 CH4排放。27429
毕业论文关键词:秸秆沟埋还田;产甲烷菌群;稻田;相对贡献率;
Effects of ditch-buried straw return on methane production inpaddy fieldAbstract:Ditch-buried straw return (DB-SR) is a new type of soil tillage practice. Previous studies havefound that DB-SR can change the process of carbon and nitrogen cycling. However, it is not clear whetherthe effect of DB-SR on the function of methanogenic bacteria. The relative contribution of different soilconditions in paddy field determination of methanogens CH4 production capacity and reduction of H2/CO2pathway and CH3COOH pathway through the oxidation rate of incubation of DB-SR effect onMethanogens function, in order to reveal the regulatory mechanism of straw burying straw on CH4emission from paddy field. Three single factor experiments were designed, including buried depth (CK, 20cm, 30 cm and 40 cm), returning amount (CK, half, full and double amounts) and returning methods (CK,rotary tillage, ditch-buried by machine and manual operation). Our results showed that the 0-10 cm surfacesoil samples, CH4 production capacity was the weakest for the burial depth of 30 cm treatment, and therelative contribution of acetic acid oxidation pathway was the smallest; for the buried amount treatments,CH4 production capacity is higher for the full amount treatment than that of other treatments, and therelative contribution of H2/CO2 reduction was greater than other two burial amount treatments. Fordifferent straw returning modes, CH4 production capacity was lower for straw incorporation with rotarytillage than that of other treatments, and the relative contribution of CH3COOH oxidation pathway was thesmallest. In summary, theCH4 production capacity of methanogens was the weakest when full amounts ofstraws were buried at a depth of 30 cm, which indicated that this technique could effectively control theCH4 emission.Key words: Ditch-buried straw return; Methanogenic bacteria;Paddy field; Relative contribution

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目 录
摘要1
关键词1
Abstract1
Key words1
引言 1
1 材料与方法2
1.1 材料及实验地情况 2
1.2 实验设计 2
1.3 实验方法 3
131 取样方法3
132 测定方法3
1.3.3 数据分析3
2 结果与分析3
2. 1 沟埋深度3
2.1.1 CH4产生能力分析.3
2.1.2 沟埋深度对 CH4产生途径的影响4
22 还田量5
2.2.1 CH4产生能力分析5
2.2.2 还田量对 CH4产生途径的影响5
23 还田方式6
2.3.1 CH4产生能力分析6
2.3.2 还田方式对 CH4产生途径的影响6
3 讨论 7
3.1 沟埋深度对稻田产甲烷菌群功能的影响7
3.2 还田量对稻田产甲烷菌群功能的影响7 秸秆沟埋还田对稻田产甲烷菌群功能的影响:http://www.lwfree.cn/shengwu/20180826/21908.html
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