基于秸秆堆肥和水肥一体化的化肥减量技术研究

发布时间：2018-05-14 07:31

本文选题：复合菌剂 + 秸秆堆肥　；参考：《西南大学》2017年硕士论文

【摘要】：我国农业生产中,长期过量投入化肥,造成农业面源污染。秸秆堆肥还田能够减少化肥用量、改善土壤理化性质,复合菌剂适应高温堆肥环境的能力强、酶系全,应用效果优于接种单一菌株的堆肥处理;黄腐酸钾(FA-K)是一种水溶性有机复合肥料,能够结合植物生长所需的营养元素,其缓释效应可为植物生长提供较长时间的营养支持;水肥一体化是一种公认的节水、节肥技术,已在国内外广泛应用。因此,本研究筛选出一种可有效降解秸秆的复合菌剂,并证实水肥一体化滴灌黄腐酸钾能够提高土壤保氮能力、促进黄瓜生长,再以复合菌剂秸秆堆肥为底肥、水肥一体化滴灌黄腐酸钾和水溶性化肥为追肥,探讨减量施用化肥的途径及其对黄瓜产量与品质的影响。取得了如下主要研究结果:(1)利用实验室分离获得的15株高效纤维素降解菌,筛选出可有效降解秸秆的复合菌剂JFB-1。结果表明,接种该复合菌剂能将秸秆堆肥的单个发酵周期缩短1~2 d,总腐熟时间减少2~4 d,堆肥中有机质含量达到403.5~515.1 g·kg~(-1),C/N比降低至15.30~10.53。总体来说,施用水稻秸秆堆肥的效果好于相应的芦笋秸秆堆肥。与只接种辅助菌的水稻秸秆对照堆肥相比,JFB-1处理的水稻秸秆堆肥150 g·kg~(-1)时,土壤中有机质和全氮含量分别提高33.5%和7.3%,土壤脲酶和纤维素酶活性分别提高16.7%和30.8%;与不施肥处理相比,施用水稻秸秆堆肥可改善土壤微生物群落结构,微生物多样性指数Shannon指数增加56.0%,Simpson指数增加77.7%,McIntosh指数增加72.9%。当JFB-1处理的水稻秸秆堆肥用量为100 g·kg~(-1)时,栽培30 d的普通白菜生物量比水稻秸秆对照堆肥提高46.4%。(2)利用水肥一体化滴灌黄腐酸钾种植黄瓜,监测黄瓜生长期土壤中NH_4~+-N和NO_3~--N含量变化,探讨黄瓜生长需肥规律,提出前期可侧重使用NH_4~+-N,花期后追加NO_3~--N达到精准施肥;测定各时期土壤总氮含量,证实水肥一体化滴灌黄腐酸钾能够有效增强土壤的保氮能力。水肥一体化滴灌黄腐酸钾可以降低土壤的硝化作用强度,防止次生盐渍化的发生,还可抑制兼性厌氧的硝酸还原酶活性,证明水肥一体化滴灌黄腐酸钾可以发挥黄腐酸钾改良土壤的作用,减少土壤中氮素的流失和温室气体的排放,降低农业面源污染。对于硝化作用,发现黄腐酸钾对氨氧化古菌(AOA)与氨氧化细菌(AOB)的作用相反,水肥一体化滴灌黄腐酸钾抑制土壤AOA的生长,促进土壤AOB的生长;对于反硝化作用,相比于nirK基因,nirS基因对肥料施用量更敏感,黄腐酸钾对nirS和nirK丰度无明显影响。(3)使用水肥一体化滴灌黄腐酸钾,当施肥量为常规施肥量的一半时,即N:209.1 kg·hm~(-2),P2O5:166.2 kg·hm~(-2),K2O:265.2 kg·hm~(-2),黄腐酸钾:225 kg·hm~(-2),黄瓜株高、茎粗和叶绿素含量等生长指标超过农民习惯施肥,此时黄瓜产量最高达35.41 t·hm~(-2),比相同施肥量不施用黄腐酸钾的处理增加37.0%,比常规施肥处理增加10.8%,表明利用水肥一体化滴灌黄腐酸钾能够发挥其促生作用。(4)化肥替代实验证实,当氮肥、秸秆堆肥和黄腐酸钾用量分别为0.263、75和0.28 g·kg~(-1)时,黄瓜的产量和品质均较高,此时化肥减量达50%。黄腐酸钾用量一定时,化肥和秸秆堆肥用量对黄瓜果实中Vc含量呈先促进后抑制的趋势;黄瓜果实中可溶性糖的含量与黄腐酸钾用量呈正相关;化肥和秸秆堆肥用量均与黄瓜果实中NO_3~--N含量正相关,但化肥的贡献远高于秸秆堆肥。
[Abstract]:The results were as follows : ( 1 ) The results were as follows : ( 1 ) The results were as follows : ( 1 ) The results were as follows : ( 1 ) The results were as follows : ( 1 ) The results were as follows : ( 1 ) The soil microbial community structure could be improved by using the composite microbial inoculum . The results showed that : ( 1 ) The soil microbial community structure , the Shannon index of soil urease and cellulase increased by 65.0 % , the Simpson index increased by 77.7 % and the McIntosh index increased by 72.9 % . ( 2 ) Using water - fertilizer integrated drip irrigation , the content of NH _ 4 ~ + - N and NO _ 3 ~ - N in the soil of cucumber was monitored . ( 4 ) The yield and quality of cucumber were higher when the dosage of fertilizer and straw compost were 0.263 , 75 and 0.28 g 路 kg ~ ( -1 ) respectively . The content of soluble sugar in cucumber fruits was positively correlated with the content of NO _ 3 ~ - N in cucumber fruits , but the contribution of fertilizer was much higher than that of straw compost .

【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S642.2;S141.4

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