本文選題：長期施肥　切入點：地膜覆蓋　出處：《沈陽農業(yè)大學》2016年博士論文　論文類型：學位論文

【摘要】：長期施肥和地膜覆蓋影響土壤理化性質,進而影響土壤微生物群落結構和多樣性,而微生物多樣性對于維持土壤生態(tài)系統(tǒng)功能至關重要。關于施肥對土壤微生物多樣性影響的研究已有不少,然而這些研究大多采用PCR-DEEG或磷脂脂肪酸(PLFA)等方法,不能從基因水平揭示土壤微生物的多樣性,高通量測序的出現(xiàn)成功彌補了這一缺陷。同時,土壤微生物群落中的氨氧化細菌和古菌因其在氮循環(huán)過程中的重要作用受到了廣泛關注。因此,本文選擇沈陽農業(yè)大學后山長期施肥定位試驗田為研究對象,采用高通量測序手段研究了長期施用化肥、有機肥以及和地膜覆蓋相結合等農田措施對土壤微生物多樣性和群落結構的影響；同時研究了氨氧化細菌和氨氧化古菌對施肥和地膜覆蓋的響應,主要發(fā)現(xiàn)如下：(1)高通量測序結果顯示研究土壤中的主要細菌門類有：蛋白菌門(Proteobacteria)、酸桿菌門(Acidobacteria)、放線菌門(Actinobacteria)、擬桿菌門(Bacteroidetes)和硬壁菌門(Firmicutes)。研究發(fā)現(xiàn)長期施用化肥結合有機肥顯著的降低了土壤微生物的多樣性,而單獨施用有機肥則提高了土壤微生物的多樣性,這與化肥顯著降低土壤pH值密切相關。研究發(fā)現(xiàn)地膜覆蓋對土壤微生物群落結構有顯著影響,這種影響主要是通過對土壤有機碳、總氮、有效磷、pH以及土壤水分的間接作用實現(xiàn)的。(2)與不施肥處理相比,長期施用化肥或有機肥顯著降低了氨氧化細菌和氨氧化古菌的相對豐度；長期施用有機肥土壤中氨氧化細菌和氨氧化古菌的相對豐度顯著高于施用化肥的土壤�？傮w上講,地膜覆蓋后氨氧化細菌和古菌的相對豐度均顯著降低。(3)總體上講,六月和七月土壤樣品中的微生物多樣性顯著高于十月,同時氨氧化細菌和古菌的豐度也呈現(xiàn)相同的規(guī)律,這與溫度和水分有較大的關系。相對于六月,七月和十月份長期施用化肥顯著降低了土壤微生物的豐度和多樣性；在七月,長期施用化肥顯著降低了氨氧化細菌的相對豐度,然而在十月,長期施用化肥顯著提高了氨氧化細菌的相對豐度。可見,土壤微生物群落多樣性以及氨氧化細菌和古菌的相對豐度對施肥和地膜覆蓋的響應因取樣時間的不同而不同,因此,未來研究應在年內和年間進行多次取樣以作出綜合評價。
[Abstract]:Long-term fertilization and film mulching affect the physical and chemical properties of soil, and then affect the structure and diversity of soil microbial community. But microbial diversity is very important to maintain the function of soil ecosystem. There have been many studies on the effects of fertilization on soil microbial diversity. However, most of these studies are carried out by PCR-DEEG or phospholipid fatty acid (PLFA). The diversity of soil microbes could not be revealed at the gene level, and the emergence of high-throughput sequencing made up for this defect. Ammonia-oxidizing bacteria and archaea in soil microbial community have been paid more and more attention for their important role in nitrogen cycling. Therefore, the long-term fertilization experiment field of Houshan, Shenyang Agricultural University, was chosen as the research object in this paper. The effects of long-term application of chemical fertilizer, organic fertilizer and mulching on soil microbial diversity and community structure were studied by high-throughput sequencing. At the same time, the responses of ammonia-oxidizing bacteria and ancient ammonia-oxidizing bacteria to fertilization and mulching were studied. The main results of high-throughput sequencing showed that the main bacteria in the soil studied were Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetesand Firutmicesus. Fertilizer significantly reduced soil microbial diversity, Application of organic fertilizer alone increased the diversity of soil microbes, which was closely related to the significant reduction of soil pH value by chemical fertilizers. The results showed that mulch mulching had a significant effect on the structure of soil microbial communities. This effect was mainly achieved by indirect effects on soil organic carbon, total nitrogen, available phosphorus pH and soil moisture. Long-term application of chemical fertilizer or organic fertilizer significantly reduced the relative abundance of ammonia-oxidizing bacteria and ammonia-oxidizing ancient bacteria, and the relative abundance of ammonia-oxidizing bacteria and ammonia-oxidizing ancient bacteria in long-term application of organic fertilizer was significantly higher than that of the soil applying chemical fertilizer. The relative abundance of ammonia-oxidizing bacteria and archaea decreased significantly after mulching film.) on the whole, the microbial diversity in soil samples on June and July was significantly higher than that in October, and the abundance of ammonia-oxidizing bacteria and archaea was the same. Compared with June, July and October, long-term application of chemical fertilizer significantly reduced the abundance and diversity of microbes in soil, and in October, long-term application of chemical fertilizer significantly reduced the relative abundance of ammonia-oxidizing bacteria. In October, however, long-term application of chemical fertilizers significantly increased the relative abundance of ammonia-oxidizing bacteria. The diversity of soil microbial communities and the relative abundance of ammonia-oxidizing bacteria and palaeomycetes are different in response to fertilization and mulching with different sampling times. Therefore, a number of samples should be taken for comprehensive evaluation during the year and each year in the future.
【學位授予單位】：沈陽農業(yè)大學
【學位級別】：博士
【學位授予年份】：2016
【分類號】：S154.3
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本文編號：1577837