侯梅芳, 潘棟宇 黃賽花, 劉超男*, 趙海青, 唐小燕
微生物修復(fù)土壤多環(huán)芳烴污染的研究進(jìn)展
侯梅芳1,2, 潘棟宇1, 黃賽花2, 劉超男1*, 趙海青1,2, 唐小燕1,2
1. 上海應(yīng)用技術(shù)學(xué)院,上海 210418;2. 廣東省生態(tài)環(huán)境與土壤研究所,廣東 廣州 510650
多環(huán)芳烴是一類(lèi)具有致癌、致畸、致突變性質(zhì)的持久性有機(jī)污染物,主要來(lái)源于煤、石油等燃料的不完全燃燒,易吸附于固體顆粒表面和有機(jī)腐殖質(zhì),化學(xué)結(jié)構(gòu)穩(wěn)定,能長(zhǎng)期存在于自然環(huán)境,給人類(lèi)健康和生態(tài)環(huán)境帶來(lái)很大的危害。中國(guó)土壤多環(huán)芳烴污染嚴(yán)重,因此急需尋求有效的修復(fù)方法進(jìn)行治理。在眾多的多環(huán)芳烴污染修復(fù)方法中,微生物修復(fù)因其低成本、高效、污染少等優(yōu)點(diǎn)成為研究熱點(diǎn)??茖W(xué)家們從自然界中分離出了多種細(xì)菌、真菌等具有降解多環(huán)芳烴能力的微生物,并對(duì)多環(huán)芳烴的降解機(jī)理進(jìn)行了探索,結(jié)果表明,微生物在代謝活動(dòng)過(guò)程中能夠產(chǎn)生酶來(lái)實(shí)現(xiàn)對(duì)土壤中多環(huán)芳烴的降解。細(xì)菌主要通過(guò)產(chǎn)生雙加氧酶來(lái)催化多環(huán)芳烴的加氧反應(yīng),而真菌可以通過(guò)分泌木質(zhì)素降解酶系或單加氧酶來(lái)氧化多環(huán)芳烴。兩種途徑均是首先通過(guò)降低多環(huán)芳烴的穩(wěn)定性,使之容易被進(jìn)一步降解。目前,微生物修復(fù)技術(shù)正逐步應(yīng)用于PAHs污染土壤的實(shí)地修復(fù),且已取得一定成效。文章簡(jiǎn)要介紹了降解多環(huán)芳烴的微生物,對(duì)多環(huán)芳烴的微生物降解機(jī)制進(jìn)行了綜述,討論了影響微生物修復(fù)過(guò)程的因素,列舉了常見(jiàn)的微生物修復(fù)相關(guān)技術(shù),展望了今后的研究趨勢(shì)。
多環(huán)芳烴;土壤污染;生物降解;降解機(jī)理;生物修復(fù)
多環(huán)芳烴(Polycyclic aromatic hydrocarbons,PAHs)是一類(lèi)有兩個(gè)或兩個(gè)以上稠合苯環(huán)結(jié)構(gòu)的化合物,具有疏水性及低水溶性,易吸附于固體顆粒,能長(zhǎng)期存在于環(huán)境中,是一種持久性有機(jī)污染物(Hadibarata和Kristanti,2012;Quilliam等,2013)。多環(huán)芳烴廣泛存在于土壤、沉積物、地下水和大氣中,其來(lái)源有化石燃料燃燒、煤氣和煤焦油的生產(chǎn)、木材加工、石油泄漏以及廢物焚燒等(Bamforth和Singleton,2005)。由于多環(huán)芳烴具有極強(qiáng)的致癌、致畸和致突變性(Josephson,1984;Phillips,1983),同時(shí)還具有神經(jīng)毒性(Grova等,2011),美國(guó)環(huán)境保護(hù)署已將16種多環(huán)芳烴確定為優(yōu)先控制污染物(Keith和Telliard,1979)。中國(guó)是一個(gè)PAHs污染特別嚴(yán)重的國(guó)家,也是PAHs排放量大的國(guó)家。據(jù)估算,中國(guó)PAHs的年排放總量超過(guò)25000 t,城市平均排放密度為158 kg·km-2,局部鄉(xiāng)村地區(qū)排放密度高達(dá)479 kg·km-2(Zhang等,2006)。由于長(zhǎng)期存在高PAHs的排放量,因而環(huán)境中PAHs的含量也不斷上升。上海市土壤中Σ26PAHs的平均濃度達(dá)2420 ng·g-1,Σ16PAHs的平均濃度達(dá)1970 ng·g-1(Wang等,2013),沈陽(yáng)某灌溉農(nóng)田土壤中PAHs總量甚至高達(dá)610.9 ~ 6362.8 μg·kg?1(表層土0 ~ 20 cm)、404.6 ~ 4318.5 μg·kg?1(表層土20 ~ 40 cm)(Zhang等,2010)。人們?nèi)糸L(zhǎng)期暴露于含PAHs的環(huán)境中,對(duì)身體健康造成極大的傷害。農(nóng)作物在含PAHs的環(huán)境中生長(zhǎng),會(huì)吸收PAHs,然后通過(guò)生物放大間接給人類(lèi)帶來(lái)危害。因此,如何降解環(huán)境中的PAHs,減少環(huán)境風(fēng)險(xiǎn),已越來(lái)越受到人們的重視。
微生物降解是一種可以將高毒、結(jié)構(gòu)復(fù)雜的有機(jī)物轉(zhuǎn)變?yōu)榈投净驘o(wú)毒、結(jié)構(gòu)簡(jiǎn)單的化合物的污染修復(fù)技術(shù),并具有高效、低成本、污染少等優(yōu)點(diǎn)(Haritash和Kaushik,2009)。微生物降解已成為最主要的多環(huán)芳烴污染土壤的修復(fù)技術(shù)。降解多環(huán)芳烴的微生物主要為細(xì)菌和真菌。
自然界中具有PAHs降解能力的細(xì)菌眾多,對(duì)PAHs的遷移和轉(zhuǎn)化具有重要的貢獻(xiàn),如芽胞桿菌屬(Bacillus)、分枝桿菌屬(Mycobacterium)、假單胞菌屬(Pseudomonas)等(鄒德勛等,2006)。
Debruyn等(2009)研究美國(guó)伊利湖中PAHs的生物降解時(shí)發(fā)現(xiàn),分支桿菌在伊利湖中的分布甚廣,且對(duì)PAHs的自然衰減和循環(huán)起著重要作用。大多數(shù)經(jīng)過(guò)馴化或從PAHs污染物中分離出來(lái)的細(xì)菌能夠?qū)AHs進(jìn)行一定程度上的降解。Zeng等(2010)從PAHs污染的農(nóng)田土壤中分離出NJS-1和NJS-P兩種分支桿菌菌株,研究它們?cè)诃傊迳蠈?duì)PAHs的降解時(shí)發(fā)現(xiàn):上述兩菌株均能夠?qū)拧⒎?、熒蒽、蒽及苯并[a]芘進(jìn)行降解。Balachandran等(2012)從印度某地受PAHs污染的土壤中分離出鏈霉菌(Streptomycetaceae),并研究其對(duì)石油和PAHs的降解,結(jié)果發(fā)現(xiàn)鏈霉菌在7 d內(nèi)(303 K)對(duì)柴油、萘、菲去除率分別達(dá)到98.25%、99.14%、17.5%。
相較于細(xì)菌而言,真菌能降解PAHs的種類(lèi)并不多,但降解PAHs的效率通常高于細(xì)菌,特別是在降解高環(huán)多環(huán)芳烴方面表現(xiàn)突出。很多研究表明,一些絲狀真菌(filamentous fungi)、擔(dān)子菌(basidiomycetes)、白腐菌(white-rot fungi)和半知菌(deuteromycetes)對(duì)四環(huán)或者更高環(huán)數(shù)PAHs的降解具有一定的優(yōu)勢(shì)。其中白腐菌(white-rot fungi)可分泌由過(guò)氧化物酶和漆酶等組成的胞外木質(zhì)素降解酶系,形成具有高效PAHs降解體系,對(duì)芘、苯[a]并芘等的降解效果明顯(Field等,1992;Acevedo等,2011;Hadibarata和Kristanti,2012)。
2.1好氧降解
好氧生物降解過(guò)程也稱(chēng)為有氧呼吸,指微生物在有氧的情況下對(duì)污染物質(zhì)的降解過(guò)程,是目前最主要的生物修復(fù)技術(shù)。
好養(yǎng)細(xì)菌降解多環(huán)芳烴主要是通過(guò)產(chǎn)生雙加氧酶作用于苯環(huán),在芳環(huán)上加入兩個(gè)氧原子,然后再經(jīng)過(guò)氧化形成順式二氫二羥基化菲,順式二氫二羥基化菲繼續(xù)脫氫形成單純二羥基化的中間體,而后被進(jìn)一步代謝為鄰苯二甲酸等其他中間產(chǎn)物,有望最終降解為水和二氧化碳。圖1以菲為代表列出了好養(yǎng)細(xì)菌降解多環(huán)芳烴的一般途徑(Moody等,2001)。
真菌對(duì)多環(huán)芳烴的降解可分為兩種不同的機(jī)制:一是木質(zhì)素降解酶系體系(Hammel等,1992),二是單加氧酶降解體系(Bezalel等,1997)(圖2)。木質(zhì)素降解酶系包括木質(zhì)素過(guò)氧化物酶、錳過(guò)氧化物酶和漆酶,這些酶對(duì)底物的作用不具有特異性,能夠氧化很多不同種類(lèi)的有機(jī)物(Tuor等,1995)。真菌通過(guò)向胞外分泌木質(zhì)素降解酶可將PAHs氧化成醌,然后經(jīng)過(guò)加氫、脫水等作用使PAHs得到降解(Haemmerli等,1986)。單加氧酶對(duì)PAHs的降解機(jī)制是在細(xì)胞色素P-450單加氧酶的催化作用下向多環(huán)芳烴苯環(huán)上加氧形成芳香環(huán)氧化物,然后經(jīng)環(huán)氧化物水解酶催化水合形成反式二氫二羥基化中間體;催化加氧反應(yīng)得到的有些芳香環(huán)氧化合物不穩(wěn)定,將繼續(xù)反應(yīng)生成酚的衍生物,并與硫酸鹽、葡萄糖、木糖或葡糖醛酸結(jié)合進(jìn)行重排,得到高水溶性、低毒性的降解中間產(chǎn)物,其更容易被進(jìn)一步降解。
圖1 好氧細(xì)菌降解多環(huán)芳烴(菲)的一般途徑Fig.1 General degradation pathway of polycyclic aromatic hydrocarbons (phenanthrene) by aerobic bacteria
總體而言,無(wú)論是細(xì)菌還是真菌,多環(huán)芳烴的好氧降解的第一步均是向苯環(huán)上加入氧原子,加氧
的快慢決定微生物對(duì)PAHs降解的效率。
圖2 好氧真菌降解多環(huán)芳烴(菲)的一般途徑Fig.2 General degradation pathway of polycyclic aromatic hydrocarbons (phenanthrene) by aerobic fungi
2.2厭氧降解
厭氧微生物可以利用硝酸鹽、硫酸鹽、鐵、錳和二氧化碳等作為其電子受體,將有機(jī)化合物分解成更小的組分,往往以二氧化碳和甲烷作為最終產(chǎn)物。與好氧降解相比,PAHs的厭氧降解進(jìn)程較慢。當(dāng)PAHs濃度偏高時(shí),PAHs的厭氧降解明顯被抑制。
文獻(xiàn)關(guān)于多環(huán)芳烴厭氧降解機(jī)制的報(bào)道以萘居多,而有關(guān)微生物厭氧降解高環(huán)數(shù)多環(huán)芳烴的報(bào)道很少。Zhang和Young(1997)的研究表明,厭氧降解萘和菲的第一步是羧化作用,苯環(huán)上的H被羧基取代分別形成2-萘甲酸和菲羧酸。Annweiler等(2002)對(duì)萘的厭氧降解做了進(jìn)一步研究,萘經(jīng)羧化形成2-萘甲酸后激活了苯環(huán)的水解活性,然后2-萘甲酸經(jīng)過(guò)逐級(jí)的氫化作用轉(zhuǎn)化為十氫-2-萘甲酸(圖3)。關(guān)于菲的厭氧降解,Tsai等(2009a;2009b)做了相關(guān)研究,但菲的苯環(huán)裂解機(jī)制尚不明確。
3.1PAHs的性質(zhì)
PAHs的性質(zhì)主要指PAHs的可生物利用性,是影響微生物修復(fù)的重要因素之一。PAHs是憎水性物質(zhì)。隨著環(huán)數(shù)的增加,PAHs的憎水性增強(qiáng),揮發(fā)性也減小,易吸附于固體顆粒表面和有機(jī)腐殖質(zhì)(陳來(lái)國(guó)等,2004;羅雪梅等,2004)。有研究表明,PAHs吸附在土壤中的時(shí)間越久越不易被生物利用(Paul等,1995)。為此,人們常通過(guò)增加表面活性劑、溶解性有機(jī)質(zhì)、有機(jī)酸等以便將PAHs從固體顆粒表面和有機(jī)腐殖質(zhì)中解吸出來(lái),從而提高微生物的可利用性。劉魏魏等(2010)研究了生物表面活性對(duì)微生物修復(fù)多環(huán)芳烴污染土壤的影響,結(jié)果發(fā)現(xiàn)添加鼠李糖脂和接種多環(huán)芳烴專(zhuān)性降解菌能明顯促進(jìn)土壤中PAHs總量和各組分PAHs的降解。
3.2氧
無(wú)論是真菌還是細(xì)菌在好氧代謝多環(huán)芳烴時(shí),氧是微生物進(jìn)行好氧代謝的重要物質(zhì)條件(Gibson等,1968)。目前生物修復(fù)技術(shù)中的氧源主要有O2和H2O2(Hinchee等,1991)等。Boyd等(2005)測(cè)定了溶解氧對(duì)淡水河口底泥中PAHs生物降解的影響,當(dāng)溶解氧高于70%時(shí),PAHs的礦化率呈指數(shù)型增長(zhǎng),而溶解氧低于40%時(shí),PAHs的礦化受到抑制,因此環(huán)境中氧的含量充足與否對(duì)多環(huán)芳烴的好氧降解有著重要的影響。在以H2O2作為氧源的生物修復(fù)技術(shù)中,適當(dāng)增加H2O2能夠增強(qiáng)PAHs的氧化效率,但濃度過(guò)高會(huì)對(duì)微生物細(xì)胞產(chǎn)生毒害作用(Pardieck等,1992),在實(shí)際操作過(guò)程中應(yīng)當(dāng)把握好H2O2的用量,從而使H2O2毒性最小化,提高PAHs氧化率。
圖 3萘的厭氧降解途徑Fig.3 Anaerobic degradation pathway of naphthalene
3.3溫度
溫度是土壤中微生物活性的重要影響因素,土壤中細(xì)菌和真菌的最適生長(zhǎng)溫度為298~303 K(Pietik?inen等,2005)。在不同溫度條件下微生物對(duì)PAHs的降解有著明顯的差異,低溫條件下微生
物活性會(huì)受到抑制,致使微生物對(duì)PAHs的降解能力下降;高溫條件下酶會(huì)因結(jié)構(gòu)被破壞而失去活性、微生物存活率降低,也會(huì)使微生物對(duì)PAHs的降解能力下降。Bauer和Capone(1985)研究了土著微生物對(duì)海洋底泥中蒽的降解,微生物在303 K的條件下對(duì)蒽的礦化效率最高,293 K和303 K條件下蒽的礦化分別是283 K下的2倍和3倍。另外在恒溫與變溫條件下,微生物對(duì)PAHs的去除效果也有差別(Antizar-Ladislao等,2007)。
溫度除了影響微生物活性之外,還會(huì)引起土壤中氧的含量和PAHs性質(zhì)的變化,間接對(duì)PAHs的降解產(chǎn)生影響。Maliszewska-Kordybach(1993)的研究發(fā)現(xiàn),土壤中PAHs濃度會(huì)隨著溫度升高而減少。
3.4pH
土壤微生物對(duì)pH值的變化敏感,當(dāng)pH降低,土壤微生物多樣性下降(Staddon等,1998);當(dāng)pH值小于5.0時(shí),生物活性受阻(單勝道等,2000),因而微生物對(duì)PAHs的降解能力會(huì)受到周?chē)h(huán)境pH的影響。Zhao等(2009)在上海某煉油廠(chǎng)區(qū)域分離出施氏假單胞菌(Pseudomonas stutzeri)ZP2,研究其對(duì)菲的降解發(fā)現(xiàn)最適pH為8.0。有些微生物則對(duì)環(huán)境中pH的變化并不是很敏感,例如K?stner等(1998)發(fā)現(xiàn)一株少動(dòng)鞘氨醇單胞菌(Sphingomonas paucimobilis)BP9在pH值為5.2和7.0的條件下對(duì)芘的降解效果基本相同。對(duì)于某些嗜極性菌種,在極性pH條件下也能降解PAHs(Stapleton等,1998)。
3.5營(yíng)養(yǎng)物質(zhì)
碳源、氮源以及無(wú)機(jī)鹽是微生物生長(zhǎng)所必需的營(yíng)養(yǎng)物質(zhì),然而微生物對(duì)營(yíng)養(yǎng)物質(zhì)的量要求不盡相同,如少動(dòng)鞘氨醇單胞菌(Sphingomonas paucimobilis)EPA505能夠利用熒蒽作為唯一碳源和能源進(jìn)行生長(zhǎng)(Ye等,1995)。給微生物提供充足的營(yíng)養(yǎng)物質(zhì)可以提高微生物修復(fù)性能。
土壤微生物修復(fù)技術(shù)是指利用PAHs降解菌在適宜的條件下,通過(guò)自身的代謝活動(dòng)對(duì)土壤中PAHs進(jìn)行轉(zhuǎn)化、降解與去除的方法。以下介紹3種常用的PAHs生物修復(fù)技術(shù):原位處理法、堆肥法、生物反應(yīng)器法。
4.1原位處理法
原位處理指在現(xiàn)場(chǎng)以土壤作為處理系統(tǒng)通過(guò)微生物的自然代謝方式來(lái)完成對(duì)污染土壤修復(fù)的技術(shù)。一般可在土壤中加入營(yíng)養(yǎng)鹽、水和氧來(lái)刺激土著微生物對(duì)PAHs的代謝,必要時(shí)還可以引入微生物、添加表面活性劑來(lái)提高微生物降解能力。此方法適用于處理污染面積大,污染深度高的土壤。Mahmoudi等(2013)在路易斯安那州鹽澤地,研究了土著微生物群對(duì)該地深水平線(xiàn)下石油污染土壤的處理狀況;在石油污染的區(qū)域在深度為3 m的范圍內(nèi),未溶解的復(fù)雜混合物濃度為26465~50380 mg·kg-1;烷烴濃度為1303~6987 mg·kg-1;PAHs濃度為16.2~99.4 mg·kg-1;經(jīng)過(guò)11個(gè)月的微生物處理,污染物濃度去除了80%~90%,18個(gè)月后污染物濃度基本得到去除。
4.2堆肥法
堆肥一般用于降解固體廢物,最近也被作為一種修復(fù)多環(huán)芳烴污染土壤的技術(shù)進(jìn)行研究。堆肥的基質(zhì)和肥料中含有大量細(xì)菌,放線(xiàn)菌和真菌能夠降解土壤中大部分有機(jī)污染物(Semple等,2001)。Cai等(2007)研究了用堆肥法降解污泥中的多環(huán)芳烴,將稻稈與含有PAHs的污泥混合,加入木屑作為膨脹劑,再用自來(lái)水和糞便污水維持污泥濕度不變,經(jīng)過(guò)56 d堆肥處理,其結(jié)果發(fā)現(xiàn)連續(xù)曝氣堆肥和間歇式曝氣堆肥對(duì)污泥中PAHs的去除率分別為85%、94%。
4.3生物反應(yīng)器
生物反應(yīng)器是一種特定設(shè)計(jì)制作的容器,可將污染土壤置于其中,利用微生物的代謝作用可實(shí)現(xiàn)對(duì)污染物的降解。生物反應(yīng)器能夠使微生物和土壤均勻混合,極大地增加微生物與污染物的接觸率,從而提高修復(fù)效率。Moscoso等(2012)在連續(xù)攪拌釜內(nèi)加入葡萄球菌和芽孢桿菌,采用補(bǔ)料-分批培養(yǎng)的方式降解含菲、芘及苯[a]并蒽的土壤,經(jīng)過(guò)培養(yǎng)發(fā)現(xiàn)菲、芘和苯[a]并蒽的降解率都接近100%。Wang等(2010)對(duì)兩-液-相反應(yīng)器中土著微生物群修復(fù)PAHs污染土壤的性能做了研究,以硅油作為有機(jī)相增加PAHs的可生物利用性,結(jié)果發(fā)現(xiàn)萘、芴、菲、蒽、熒蒽、芘在4 ~ 50 d可以被生物完全地降解;高環(huán)PAHs在經(jīng)過(guò)幾個(gè)延滯期后也迅速的得到降解。另外,向生物反應(yīng)器中加入有機(jī)廢棄物可以強(qiáng)化微生物對(duì)PAHs污染土壤的修復(fù)(楊婷等,2009)。上述研究表明,生物處理器對(duì)PAHs污染土壤的修復(fù)具有很好的效果,然而實(shí)際運(yùn)行費(fèi)用較高,應(yīng)用不是很廣。
總的來(lái)看,PAHs的生物修復(fù)具有多樣性,在對(duì)多環(huán)芳烴污染土壤進(jìn)行修復(fù)時(shí),應(yīng)當(dāng)考慮土壤中PAHs的種類(lèi)和濃度、土壤性質(zhì)和污染范圍等因素,采取合適的生物修復(fù)技術(shù),以達(dá)到經(jīng)濟(jì)高效的效果。
土壤多環(huán)芳烴的污染和修復(fù)一直是人們關(guān)注的熱點(diǎn),雖然多環(huán)芳烴的修復(fù)研究已取得一定成果,但還有很多方面需要進(jìn)一步深入探索。例如:1)篩選
或培育出具有更高PAHs降解能力的微生物,并能夠?qū)ν寥乐懈攮h(huán)數(shù)PAHs實(shí)現(xiàn)高效去除;2)深入研究3環(huán)以上PAHs的微生物厭氧降解機(jī)制;3)分析微生物降解PAHs的最適環(huán)境因素和工藝過(guò)程參數(shù),進(jìn)行中試試驗(yàn)評(píng)估技術(shù)可行性,優(yōu)化修復(fù)技術(shù)體系,以便將其應(yīng)用到實(shí)際工程項(xiàng)目,提高修復(fù)效率。
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Microbial Remediation of Polycyclic Aromatic Hydrocarbons Contaminated Soil: A Review
HOU Meifang1,2, PAN Dongyu1, HUANG Saihua1,2, LIU Chaonan1*, ZHAO Haiqing1,2, TANG Xiaoyan1,2
1. Shanghai Institute of Technology, Shanghai 210418, China; 2. Guangdong Institute of Eco-environment and Soil Sciences, Guangzhou 510650, China
Polycyclic aromatic hydrocarbons (PAHs), which mainly resulted from incomplete combustion of coal, petroleum and other fuels, are a kind of carcinogenic, teratogenic and mutagenic persistent organic pollutants (POPs). Each of them has stable chemical structure and easily adsorb on solid surface and organic humus. For this case, PAHs can exist in the natural environment for a long time and has great potential harm to human health and ecological environment. In China, the PAHs pollution in soil is a very serious problem, so it is urgent to explore an effective technology for removal of PAHs. Recently, microbial remediation was focused on for its advantages of low cost, high efficiency and less pollution with PAHs-degrading bacteria and fungi. The enzymes are important in degradation of soil PAHs during microbial remediation. PAHs can be degraded through the oxidation of benzene ring by dioxygenase enzymes of bacteria. PAHs can also be oxidized by lignin degrading enzymes or monooxygenases of fungi. The stabilities of intermediates are usually lower than those of parent PAHs and can be easily further degraded. Thus, the microbial remediation has been utilized in the treatment practice of soil PAHs. In this work, the PAHs-degrading microbe and mechanism were reviewed. The influences of different factors on the microbial remediation of soil PAHs were discussed. Three microbial remediation techniques of PAHs-contaminated soil were introduced. Moreover, some suggestions were provided for the development of the microbial remediation technology to remove PAHs in soil.
Polycyclic aromatic hydrocarbons; soil pollution; biological degradation; degradation mechanism; bioremediation
X172
A
1674-5906(2014)07-1233-06
國(guó)家自然科學(xué)基金項(xiàng)目(41171250;20907011);中國(guó)科學(xué)院土壤環(huán)境與污染修復(fù)重點(diǎn)實(shí)驗(yàn)室開(kāi)放基金項(xiàng)目;上海應(yīng)用技術(shù)學(xué)院引進(jìn)人才基金項(xiàng)目(YJ2013-16)
侯梅芳(1976年生),女,教授,博士,研究方向?yàn)橥寥兰八h(huán)境污染與修復(fù)。
*通信作者:劉超男。E-mail: chaonan_liu@163.com
2014-05-12
侯梅芳, 潘棟宇, 黃賽花, 劉超男, 趙海青, 唐小燕. 微生物修復(fù)土壤多環(huán)芳烴污染的研究進(jìn)展[J]. 生態(tài)環(huán)境學(xué)報(bào), 2014, 23(7): 1233-1238.
HOU Meifang, PAN Dongyu, HUANG Saihua, LIU Chaonan, ZHAO Haiqing, TANG Xiaoyan. Microbial Remediation of Polycyclic Aromatic Hydrocarbons Contaminated Soil: A Review [J]. Ecology and Environmental Sciences, 2014, 23(7): 1233-1238.
生態(tài)環(huán)境學(xué)報(bào)2014年7期