本文選題：施肥 + 作物生產(chǎn)體系��； 參考：《中國農(nóng)業(yè)大學(xué)》2016年博士論文

【摘要】：土壤在全球主要的生物地球化學(xué)循環(huán)中發(fā)揮著關(guān)鍵的作用,并為大量生物提供了居所。團(tuán)聚體是土壤的基本結(jié)構(gòu)單元,因此是生物地球化學(xué)循環(huán)過程的重要場所。微生物是土壤生態(tài)系統(tǒng)中最活躍的部分,它們的生命活動影響著土壤碳氮循環(huán)和土壤團(tuán)聚結(jié)構(gòu)的形成和穩(wěn)定性。因此了解團(tuán)聚體中微生物分布,對于理解這些生物地球化學(xué)過程具有重要的意義。本文以華北平原長期定位試驗(yàn)平臺,系統(tǒng)分析了不同作物生產(chǎn)體系下,長期施肥對土壤養(yǎng)分、全土微生物群落結(jié)構(gòu)、團(tuán)聚體碳氮濃度和微生物群落特征等的影響。本研究具體選取以下三組作物輪作體系試驗(yàn)：(1)溫室蔬菜種植體系：有機(jī)溫室和常規(guī)溫室；(2)小麥-玉米輪作體系：有機(jī)肥、常規(guī)施肥、不施肥和自然恢復(fù)地；(3)不同作物種植模式體系：有機(jī)農(nóng)田(苜蓿-小麥-苜蓿-玉米輪作)、常規(guī)農(nóng)田(冬小麥套種夏玉米)、不施氮農(nóng)田(小麥-玉米輪作)和自然恢復(fù)地。采用濕篩法獲得3種粒徑的團(tuán)聚體：0.25 mm(大團(tuán)聚體)、0.053-0.25mm(微團(tuán)聚體)和0.053mm(粉粘粒)。同時(shí)采用實(shí)時(shí)熒光定量(qPCR)、末端限制性片段多態(tài)性分析(T-RFLP)和克隆文庫等分子生物學(xué)方法測定土壤微生物群落結(jié)構(gòu)。研究結(jié)果表明：溫室蔬菜生產(chǎn)體系中,施用有機(jī)肥可以改善土壤養(yǎng)分條件和團(tuán)聚碳氮水平。與常規(guī)管理相比,有機(jī)管理下的團(tuán)聚體有機(jī)碳和全氮濃度分別提高13-153%和30-146%。在兩種管理下,有機(jī)碳和全氮濃度都隨團(tuán)聚體粒徑的減小而降低,微團(tuán)聚體組分對全土碳氮含量貢獻(xiàn)率分別為42-65%和43-66%。與常規(guī)管理相比,有機(jī)管理可以提高團(tuán)聚體中微生物數(shù)量,對微生物多樣性的影響不顯著。冗余分析表明,溫室蔬菜生產(chǎn)條件下,微生物的分布受團(tuán)聚體結(jié)構(gòu)本身的影響。T-RFLP和克隆文庫結(jié)果表明,細(xì)菌群落中變形菌門(Proteobacteria)、放線菌門(Actinobacteria)和擬桿菌門(Bacteroidetes)在各級團(tuán)聚體中均有發(fā)現(xiàn),酸桿菌門(Acidobacteria)僅在微團(tuán)聚體和粉粘粒組分中發(fā)現(xiàn)。真菌類群在大團(tuán)聚體組分中較豐富,末端限制性片段257 bp(子囊菌門Ascomycota)及272和294 bp(接合菌門Zygomycota)在三個(gè)級別團(tuán)聚體中均有發(fā)現(xiàn)。小麥-玉米輪作生產(chǎn)體系中,長期施有機(jī)肥可以改善土壤養(yǎng)分條件,而施用化肥僅提高土壤有效磷的含量。施肥處理(有機(jī)肥和化肥)對表層土壤團(tuán)聚體中有機(jī)碳和全氮濃度影響存在差異。與不施肥對照相比,施有機(jī)肥處理對各級團(tuán)聚體中碳氮濃度有顯著的提高作用,施化肥處理提高微團(tuán)聚體組分碳氮濃度而降低大團(tuán)聚體和粉粘粒組分中碳氮濃度。在所有處理中,有機(jī)碳和全氮濃度與團(tuán)聚體粒徑大小成正比。冗余分析結(jié)果表明,團(tuán)聚體重量直徑、有機(jī)碳和全氮濃度和土壤微生物生物量呈正相關(guān),這說明團(tuán)聚體結(jié)構(gòu)和碳氮水平影響著微生物的分布。各級別團(tuán)聚體中微生物數(shù)量的分布與有機(jī)碳和全氮濃度規(guī)律相似,隨團(tuán)聚體粒徑減小而降低。在長期施肥條件下,微生物在團(tuán)聚體的分布存在差異。細(xì)菌群落中變形菌門(Proteobacteria)在大團(tuán)聚體和微團(tuán)聚體組分中分布較多,而擬桿菌門(Bacteroidetes)在微團(tuán)聚體和粉粘粒組分中聚集。真菌群落在大團(tuán)聚體組分與全土的組成相似,而在微團(tuán)聚體和粉粘粒組分結(jié)構(gòu)相似。在第三組實(shí)驗(yàn)中,作物種植模式對團(tuán)聚體有機(jī)碳、全氮濃度和微生物群落結(jié)構(gòu)產(chǎn)生不同影響。與不施氮肥處理相比,有機(jī)農(nóng)田提高了各級團(tuán)聚體中碳氮濃度,常規(guī)農(nóng)田增加了粉粘粒組分中有機(jī)碳濃度和微團(tuán)聚體與粉粘粒組分中全氮濃度。各處理團(tuán)聚體中有機(jī)碳和全氮濃度隨團(tuán)聚體粒徑減小而降低,微團(tuán)聚體組分對全土有機(jī)碳和全氮含量貢獻(xiàn)率分別為52-66%和52-69%。與不施氮肥農(nóng)田相比,有機(jī)農(nóng)田和常規(guī)農(nóng)田均提高了全土細(xì)菌的數(shù)量和多樣性,降低了真菌數(shù)量和多樣性。冗余分析表明,有機(jī)碳和全氮濃度及有效磷含量促進(jìn)了土壤真菌數(shù)量。各級土壤團(tuán)聚體中的細(xì)菌群落在存在差異,其中變形菌門(Proteobacteria)主要在大團(tuán)聚體中分布,而酸桿菌門(Acidobacteria)在微團(tuán)聚體組分中較豐富。真菌在團(tuán)聚體中分布主要受作物種植模式的影響,比如有機(jī)農(nóng)田與常規(guī)農(nóng)田對團(tuán)聚體中真菌群落結(jié)構(gòu)產(chǎn)生了顯著差異�？傊�,不同作物生產(chǎn)體系中,長期施肥能夠提高團(tuán)聚體中有機(jī)碳和全氮濃度,對團(tuán)聚體微生物群落結(jié)構(gòu)產(chǎn)生影響,但對細(xì)菌和真菌的影響規(guī)律不同。細(xì)菌群落在團(tuán)聚體中的分布受團(tuán)聚體物理結(jié)構(gòu)及碳氮水平的影響。真菌群落在團(tuán)聚體中分布受種植作物種類及施肥的共同影響。
[Abstract]:Soil plays a key role in the world's major biogeochemical cycle and provides a place for a large number of organisms. Aggregates are the basic structural units of the soil, so it is an important place for the biogeochemical cycle. Microbes are the most active part of the soil ecosystem, and their life activities affect soil carbon and nitrogen. The formation and stability of cyclic and soil agglomeration structures. Therefore, to understand the distribution of microbes in the aggregates is of great significance for understanding these biogeochemical processes. In this paper, the soil nutrient and whole soil microbial community structure under different crop production systems were systematically analyzed under the long-term positioning test platform of North China Plain. The effects of carbon and nitrogen concentration and microbial community characteristics of aggregates. The following three crop rotation system experiments were selected: (1) greenhouse vegetable planting system: Organic greenhouse and conventional greenhouse; (2) wheat maize rotation system: organic fertilizer, conventional fertilization, no fertilization and natural recovery; (3) different crop planting pattern system: (3) Organic farmland (alfalfa - wheat - alfalfa - maize rotation), conventional farmland (winter wheat interplanting summer corn), no nitrogen application (wheat - corn rotation) and natural recovery. 3 kinds of aggregate aggregates were obtained by wet screening method: 0.25 mm (large aggregate), 0.053-0.25mm (micro polymer) and 0.053mm (powder clay). Real time fluorescence quantitative (qPCR) was used at the same time. The soil microbial community structure was determined by the end restriction fragment polymorphism analysis (T-RFLP) and clone library. The results showed that the application of organic fertilizer in the greenhouse vegetable production system could improve the soil nutrient conditions and the concentration of carbon and nitrogen. The concentration of organic carbon and total nitrogen in the concentration of 13-153% and 30-146%. decreased with the decrease of aggregate particle size. The contribution rate of micro aggregate to total soil carbon and nitrogen content was 42-65% and 43-66%., respectively, compared with conventional management. Organic management could increase the amount of microorganism in the aggregate, and the effect on microbial diversity was not. In greenhouse vegetable production, the distribution of microbes was affected by the structure of aggregates,.T-RFLP and clone library results showed that Proteobacteria, Actinobacteria and Bacteroidetes were found in all levels of aggregates, and acid bacilli (Acidobacte). RIA) was found only in the micro aggregates and powder clay components. Fungal groups were more abundant in the large aggregate components, the terminal restrictive fragments 257 BP (atlum Ascomycota) and 272 and 294 BP (conjugation fungus Zygomycota) were found in three grade aggregates. In the wheat corn wheel production system, long-term organic fertilizer could improve the soil The effects of fertilizer treatment (organic manure and chemical fertilizer) on the concentration of organic carbon and total nitrogen in the surface soil aggregates were different. Compared with the non fertilization, the application of organic fertilizer treatment could improve the concentration of carbon and nitrogen in the aggregates at all levels, and the fertilizer treatment improved the micro aggregate. The concentration of carbon and nitrogen decreased the concentration of carbon and nitrogen in the large aggregate and the powder clay. In all treatments, the concentration of organic carbon and total nitrogen was proportional to the size of the aggregate. The results of redundant analysis showed that the weight diameter of the aggregate, the concentration of organic carbon and total nitrogen were positively related to the soil microbial biomass, which indicated the structure of the aggregate and the carbon and nitrogen water. The distribution of microbes in all levels of aggregates is similar to that of organic carbon and total nitrogen, and decreases with the decrease of aggregate size. In the long-term fertilization, the distribution of microbes in the aggregate is different. In the bacterial community, the Proteus (Proteobacteria) is in the large aggregate and the microaggregate components. The distribution of Bacteroidetes in the microaggregates and the powder clay fractions. The fungi community is similar to the composition of the whole soil in the large aggregate and the structure of the microaggregates and the powder clay. In the third groups, the crop planting pattern has the organic carbon, the total nitrogen concentration and the microbial community structure in the aggregate. The organic farmland increased the concentration of carbon and nitrogen in the aggregate and the concentration of organic carbon in the powder clay fractions and the concentration of total nitrogen in the microaggregates and the powder clay fractions. The contribution rate of total soil organic carbon and total nitrogen content was 52-66% and 52-69%., respectively, compared with non fertilizer nitrogen fertilizer, organic farmland and conventional farmland both increased the number and diversity of whole soil bacteria and reduced the number and diversity of fungi. The redundancy analysis showed that the organic carbon and total nitrogen and the content of the available phosphorus promoted the soil fungi. There are differences in the bacterial community in the soil aggregates, in which the Proteobacteria is mainly distributed in the large aggregates, and the acid bacilli (Acidobacteria) is more abundant in the micro aggregate components. The distribution of fungi in the aggregate is mainly influenced by the crop planting pattern, such as the organic and conventional farmland for the fungus community in the aggregate. There are significant differences in structure. In a word, long-term fertilization can increase the concentration of organic carbon and total nitrogen in the aggregate, affect the structure of the aggregate microorganism community, but have different influence on the bacteria and fungi. The distribution of the bacterial community in the aggregate is influenced by the physical structure of aggregate and the level of carbon and nitrogen in the aggregate. The distribution of fungal communities in aggregates is influenced by planting crops and fertilization.

【學(xué)位授予單位】：中國農(nóng)業(yè)大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：S154.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 CHEN Yun-Feng;CAO Zhi-Ping;L.POPESCU;B.H.KIEPPER;;Static and Dynamic Properties of Soil Food Web Structure in a Greenhouse Environment[J];Pedosphere;2014年02期

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本文編號：1789759