英國的一個(gè)聯(lián)合研究小組日前宣布,，他們成功繪制了英國首張土壤細(xì)菌分布圖,，該圖對(duì)英國土壤中的微生物進(jìn)行了迄今為止最為全面和詳盡的測(cè)定,。相關(guān)論文發(fā)表在當(dāng)日出版的《環(huán)境微生物學(xué)》雜志上。
該研究小組由來自英國生態(tài)與水文學(xué)中心,、紐卡斯?fàn)柎髮W(xué)和牛津大學(xué)的多名科學(xué)家組成,。研究人員對(duì)采集自英格蘭、蘇格蘭以及威爾士的1000份土壤鉆孔樣本進(jìn)行檢測(cè),、分析并繪制出了這幅土壤細(xì)菌分布圖,。研究顯示，細(xì)菌多樣性程度與土壤pH值密切相關(guān),，地下菌落和地面植物群落之間也存在著極為密切的關(guān)聯(lián),。細(xì)菌是土壤多樣性的主要組成部分，在維持土壤健康方面發(fā)揮著重要作用,，對(duì)種植業(yè)發(fā)展和固碳都有著十分重要的意義,。
論文第一作者,、英國生態(tài)與水文學(xué)中心的羅伯特·格里菲斯博士說：“迄今為止我們對(duì)細(xì)菌群落差異性的認(rèn)識(shí)在整體上還十分有限。新的研究首次在宏觀上對(duì)英國土壤細(xì)菌群落的分布狀況進(jìn)行了描述,，為此后土壤細(xì)菌多樣性以及土壤生態(tài)系統(tǒng)等更為復(fù)雜的研究奠定了基礎(chǔ),。”
另一研究人員安迪·懷特利教授說：“外出散步時(shí)，我們絕大多數(shù)人都不會(huì)注意到腳下那些只有通過顯微鏡才能看到的細(xì)菌,，但它們的數(shù)量和作用實(shí)際上都十分驚人：一個(gè)腳印大的一塊土壤中就有將近100億個(gè)細(xì)菌,，它們?cè)诒３滞寥婪柿Α⒕S持地球溫室氣體循環(huán)方面均發(fā)揮著不可替代的作用,。新研究中我們?cè)噲D揭開地表中這些視野之外的微型群落,，并以此來弄清菌群以怎樣的方式存在以及為什么要這樣，它們?cè)谌祟惿钪邪l(fā)揮著怎樣的作用,。”
論文的另一位合著者馬克·貝利說：“英國生態(tài)與水文學(xué)中心曾在1996年時(shí)繪制了英國首張洪水風(fēng)險(xiǎn)地圖,。15年后，我們又繪制了世界首張土壤微生物分布地圖,。從今年開始我們將把部分土壤樣品和原始數(shù)據(jù)提供給更多研究人員,，以讓它們發(fā)揮出更大的研究?jī)r(jià)值。”
此外,，本次實(shí)驗(yàn)中所使用的部分土壤樣品和細(xì)菌DNA還將被作為歷史資料冷凍保存下來,，以方便未來的研究人員研究氣候變化對(duì)土壤細(xì)菌多樣性的影響。（生物谷Bioon.com）
生物谷推薦原文出處：
Environmental Microbiology DOI: 10.1111/j.1462-2920.2011.02480.x
The bacterial biogeography of British soils
Robert I. Griffiths1,*, Bruce C. Thomson1, Phillip James1,2, Thomas Bell3, Mark Bailey1, Andrew S. Whiteley1
Summary
Despite recognition of the importance of soil bacteria to terrestrial ecosystem functioning there is little consensus on the factors regulating belowground biodiversity. Here we present a multi-scale spatial assessment of soil bacterial community profiles across Great Britain (> 1000 soil cores), and show the first landscape scale map of bacterial distributions across a nation. Bacterial diversity and community dissimilarities, assessed using terminal restriction fragment length polymorphism, were most strongly related to soil pH providing a large-scale confirmation of the role of pH in structuring bacterial taxa. However, while diversity was positively related to pH, the converse was true for β diversity (between sample variance in diversity). β diversity was found to be greatest in acidic soils, corresponding with greater environmental heterogeneity. Analyses of clone libraries revealed the pH effects were predominantly manifest at the level of broad bacterial taxonomic groups, with acidic soils being dominated by few taxa (notably the group 1 Acidobacteria and Alphaproteobacteria). We also noted significant correlations between bacterial communities and most other measured environmental variables (soil chemistry, aboveground features and climatic variables), together with significant spatial correlations at close distances. In particular, bacterial and plant communities were closely related signifying no strong evidence that soil bacteria are driven by different ecological processes to those governing higher organisms. We conclude that broad scale surveys are useful in identifying distinct soil biomes comprising reproducible communities of dominant taxa. Together these results provide a baseline ecological framework with which to pursue future research on both soil microbial function, and more explicit biome based assessments of the local ecological drivers of bacterial biodiversity.
