本文選題：微生物群落 + 類群　； 參考：《蘭州大學(xué)》2017年碩士論文

【摘要】：地上地下生物群落的偶聯(lián)不僅直接影響著生態(tài)系統(tǒng)的功能,更關(guān)系到未來全球氣候變化及生態(tài)平衡。傳統(tǒng)研究主要關(guān)注植物群落,近年來,生命科學(xué)技術(shù)方法的不斷進(jìn)步促進(jìn)了微生物群落的研究,越來越多的研究集中到基于植物-土壤-微生物相互作用的地上地下生物群落偶聯(lián)關(guān)系。青藏高原低溫、高海拔、強(qiáng)輻射的獨(dú)特生態(tài)環(huán)境使該區(qū)域長期處于寡營養(yǎng)狀態(tài),對全球氣候變化較敏感。施肥作為一種草地生態(tài)系統(tǒng)管理模式在增加地上生產(chǎn)力的同時(shí)也會(huì)對生物群落及其參與的生態(tài)過程造成影響。因此,研究地上地下生物群落及其偶聯(lián)關(guān)系對營養(yǎng)元素添加的響應(yīng)能夠?qū)ξ磥砩鷳B(tài)系統(tǒng)變化進(jìn)行預(yù)測并為其保護(hù)措施提供理論指導(dǎo)。本研究通過高通量測序及熒光定量PCR相結(jié)合的方法解析微生物群落結(jié)構(gòu)變化,構(gòu)建了地上地下生物群落營養(yǎng)限制概念模型,通過SEM(Structural Equation Modeling)模型將地上地下生物群落進(jìn)行耦合,研究青藏高原高寒草甸生態(tài)系統(tǒng)施加不同濃度氮肥(N)、磷肥(P)和氮磷肥(NP)的土壤中古菌和細(xì)菌群落的營養(yǎng)限制類型及兩者與地上植物群落的偶聯(lián)關(guān)系。主要實(shí)驗(yàn)結(jié)果如下:1.施肥對土壤微生物群落多樣性的影響土壤古菌及細(xì)菌群落高通量測序結(jié)果顯示,共測得182143條古菌序列分別屬于355個(gè)OTU和276350條細(xì)菌序列分別屬于6246個(gè)OTU,古菌與細(xì)菌群落多樣性差異顯著高于兩者之間豐富度差異,土壤中細(xì)菌群落多樣性較高。Thaumarchaeota(奇古菌門)主導(dǎo)土壤古菌群落,Proteobacteria(變形菌門)、Acidobacteria(酸桿菌門)和Actinabacteria(放線菌門)主導(dǎo)土壤細(xì)菌群落。高濃度NP和P添加分別會(huì)增加古菌群落α多樣性和降低細(xì)菌群落α多樣性。2.地上地下生物群落營養(yǎng)限制類型及其關(guān)系根據(jù)地上地下生物群落營養(yǎng)限制模型,古菌(21個(gè)OTU)、細(xì)菌(89個(gè)order/sub-order)及植物(21個(gè)物種)分別劃分至十三種營養(yǎng)限制類型(分屬五大類)。古菌群落營養(yǎng)限制類型相對單一,以P限制型類群占主導(dǎo)。細(xì)菌群落營養(yǎng)限制類型相對多元和平衡,以其他營養(yǎng)限制類群占主導(dǎo)。研究結(jié)果表明,群落和類群兩個(gè)角度的營養(yǎng)限制類型有差異,植物群落屬于N限制型,古菌群落屬于P限制型,細(xì)菌群落無可劃分類型。無論地下地上生物群落,P限制型類群均與AN:AP呈負(fù)相關(guān),N限制型類群均與AN:AP呈正相關(guān)。植物與微生物營養(yǎng)限制類群相關(guān)性分析結(jié)果顯示,植物群落對細(xì)菌群落的競爭力顯著大于古菌,屬于相似營養(yǎng)限制類型的地上地下生物群落顯著正相關(guān),因此施肥措施可緩解同類型植物及微生物之間的營養(yǎng)競爭。系統(tǒng)進(jìn)化分析結(jié)果顯示,古菌和細(xì)菌對營養(yǎng)元素的響應(yīng)沒有表現(xiàn)出顯著發(fā)育信號。但古菌類群對單獨(dú)P元素施加的響應(yīng)表現(xiàn)出功能趨同,細(xì)菌類群對N施加響應(yīng)值表現(xiàn)出顯著的功能趨同。該現(xiàn)象歸因于營養(yǎng)元素響應(yīng)特征屬于微生物簡單特征,其進(jìn)化沒有保守性,易隨環(huán)境發(fā)生改變。3.植物-土壤-微生物耦合關(guān)系植物-土壤-微生物耦合關(guān)系研究結(jié)果顯示,N施加時(shí)古菌群落受植物群落的間接影響(λ=0.900),細(xì)菌則受施肥的直接影響(λ=-0.841)。古菌群落受P施肥的直接影響(λ=-0.612),NP共施肥時(shí)古菌(λ=0.621)及細(xì)菌群落均受施肥的直接影響(λ=0.462)。結(jié)果表明,不同施肥措施對地上地下生物群落的偶聯(lián)關(guān)系有顯著影響,其中P施肥直接作用于古菌群落,氮磷共施肥對古菌及細(xì)菌群落均為直接作用。
[Abstract]:The coupling of aboveground and underground biological communities not only directly affects the function of the ecosystem, but also relates to the global climate change and ecological balance in the future. The traditional research mainly focuses on the plant community. In recent years, the continuous progress in the methods of life science and technology has promoted the research of microbial community. More and more studies have focused on plant soil based on Soil - The unique ecological environment of low temperature, high altitude and strong radiation in the Qinghai Tibet Plateau makes the region be in oligotrophic state for a long time and is sensitive to global climate change. The ecological processes involved are affected. Therefore, the study of the responses of the aboveground and underground biological communities and their coupling relationship to the nutrient elements can predict the changes in the future ecosystem and provide theoretical guidance for the protection measures. This study analyzed the microbial community structure by the combination of high throughput sequencing and fluorescence quantitative PCR The conceptual model of the nutritional restriction of the aboveground and underground biological communities was constructed, and the SEM (Structural Equation Modeling) model was used to coupling the aboveground and underground biological communities to study the nutrient restriction types of the different concentrations of nitrogen fertilizer (N), phosphorous fertilizer (P) and nitrogen phosphate (NP) soil in the alpine meadow ecosystem of the Qinghai Tibet Plateau. The main experimental results were as follows: 1. the effect of Fertilization on the diversity of soil microbial community, the result of high throughput sequencing of soil palaebacteria and bacterial community showed that 182143 Archaea sequences belonging to 355 OTU and 276350 bacteria sequences were respectively 6246 OTU, and the Archaea and the bacterial community were more. The diversity of the samples was significantly higher than the difference between the two. The diversity of the bacterial community in the soil was higher.Thaumarchaeota (Archaea) dominated the soil palaeomycetes, Proteobacteria (Proteus), Acidobacteria (acid bacilli) and Actinabacteria (actinomycetes). The high concentration of NP and P added palaeomycetes, respectively. Alpha diversity and the reduction of bacterial community alpha diversity.2. on the ground and underground biological community nutrition restriction types and their relationships according to the nutrient restriction model of the aboveground biological community, palaeo (21 OTU), bacteria (89 order/sub-order) and plants (21 species) were divided into thirteen types of nutrition restriction respectively (belonging to five categories). The restrictive types are relatively single and dominated by P restrictive groups. The relative diversity and balance of the bacterial community are dominant. The results show that there are differences in the type of nutrition restriction between the two angles of the community and the group, the plant community belongs to the N restriction type, the palaeo community belongs to the P restriction type, and the bacterial community is not delimit. P restrictive groups were negatively correlated with AN:AP and N restricted groups were positively correlated with AN:AP. The correlation analysis between plant and microbial restricted groups showed that the competitiveness of plant community to bacterial community was significantly greater than that of paleo, which belonged to the subsurface subsurface biota of similar nutrition restriction type. The results of phylogenetic analysis showed that the response of the Archaea and bacteria to the nutrient elements did not show significant development signals. However, the response of the paleo groups to the individual P elements showed a functional convergence, and the bacterial group applied the response to the N. The phenomenon is attributed to the obvious functional convergence. The phenomenon is attributed to the nutrient element response characteristic of the simple microbial characteristics, its evolution is not conserved, and it is easy to change with the environment to change the plant soil microbial coupling relationship of.3. plant soil microbial coupling relationship. The results show that the palaeo community is influenced by the plant community at the time of N (lambda =0). .900), the bacteria were affected by the direct effect of fertilization (lambda =-0.841). The Archaea community was directly affected by the fertilization of P ([lambda] =-0.612). When NP was applied, the palaebacteria ([lambda] =0.621) and the bacterial community were directly affected by the fertilization ([lambda =0.462]. The results showed that the different fertilization measures had a significant influence on the coupling relationship between the aboveground and underground biological communities, and the direct effect of P fertilization. In the Archaea community, nitrogen and phosphorus co fertilization played a direct role in archaea and bacterial communities.
【學(xué)位授予單位】：蘭州大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：S812

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 劉良梧;;土壤年齡研究[J];土壤學(xué)進(jìn)展;1981年02期

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本文編號：2099587