【摘要】：隨著現(xiàn)代工業(yè)的發(fā)展,重金屬土壤污染已成為日漸突出的環(huán)境問題,時刻威脅著動植物的生長、人類的身體健康和生態(tài)環(huán)境的破壞。國內(nèi)外許多關(guān)于土壤重金屬污染的修復(fù)研究不勝枚舉,但成果不太明顯,傳統(tǒng)的土壤重金屬污染修復(fù)方法因各種限制已不能滿足實際需求,近年來,土壤重金屬微生物修復(fù)以其高效率、無二次污染等特點,已成為國內(nèi)外一個新型的研究領(lǐng)域,引起了人們的廣泛關(guān)注。本課題前期已針對消落帶重金屬污染土壤進(jìn)行了相關(guān)植物修復(fù)技術(shù)研究,并取得一定研究進(jìn)展,修復(fù)效果理想。本研究在前期基礎(chǔ)之上,選取具有較佳植物修復(fù)效果的三峽庫區(qū)消落帶云陽段土樣為研究對象,從土樣中篩選分離出5種對銅、鋅、鎘具有去除作用的菌株。其中,B01為具有去除Cu2+作用的菌株,B02、B03為具有去除Cd2+作用的菌株,B04、B05為具有去除Zn2+作用的菌株。上述菌株經(jīng)過培養(yǎng)、富集與分離純化,初步鑒定結(jié)果為:B01、B02、B04為產(chǎn)堿菌屬;B03為黃假胞菌屬;B05為假單胞菌屬。實驗中,根據(jù)不同pH、溫度、重金屬離子初始濃度,設(shè)置單一因子變化分別配置不同的營養(yǎng)液對Cu2+、Cd2+、Zn2+的去除作用進(jìn)行觀察,其中,菌株B01去除Cu2+,菌株B02、B03去除Cd2+,菌株B04、B05去除Zn2+。實驗結(jié)果表明:菌種B01去除Cu2+的實驗,重金屬去除率分別與p H、溫度的變化曲線為先上升后下降,與Cu2+初始濃度的變化呈負(fù)相關(guān);Cu2+去除量與Cu2+初始濃度的變化曲線為先上升后下降;pH在7時,Cu2+的去除率達(dá)到最高值,為70%;溫度為30℃時,Cu2+的去除率達(dá)到最高值,為70%;Cu2+初始濃度為100mg/L時,Cu2+的去除量達(dá)到最高值,為70mg/L。菌種B01對銅的去除作用在30~100mg/L Cu2+濃度時滿足零級動力學(xué)方程。菌株B02、B03去除Cd2+的實驗,重金屬去除率分別與pH、溫度的變化曲線為先上升后下降,與Cd2+初始濃度的變化呈負(fù)相關(guān);Cd2+去除量與Cd2+初始濃度的變化曲線為先上升后下降;pH在7時,菌株B02、B03對Cd2+的去除率達(dá)到最高值,分別為66%、42%;溫度為30℃時,菌株B02、B03對Cd2+的去除率達(dá)到最高值,分別為66%、42%;Cd2+初始濃度為70mg/L時,菌株B02、B03對Cd2+的去除量達(dá)到最高值,分別為49mg/L、40.6mg/L。菌種B02、B03對鎘的去除作用在30~70mg/L Cd2+濃度時滿足零級動力學(xué)方程。菌株B04、B05去除Zn2+的實驗,重金屬去除率分別與pH、溫度的變化曲線為先上升后下降,與Zn2+初始濃度的變化呈負(fù)相關(guān);Zn2+去除量與Zn2+初始濃度的變化曲線為先上升后下降;pH在7時,菌株B04、B05對Zn2+的去除率達(dá)到最高值,分別為68%、65%;溫度為30℃時,菌株B04、B05對Zn2+的去除率達(dá)到最高值,分別為63%、58%;Zn2+初始濃度為150mg/L時,菌株B04、B05對Zn2+的去除量達(dá)到最高值,分別為67.5mg/L、61.5mg/L。菌種B04、B05對鎘的去除作用分別在10~200mg/L和10~150mg/L Zn2+濃度時滿足零級動力學(xué)方程。
[Abstract]:With the development of modern industry, heavy metal soil pollution has become an increasingly prominent environmental problem, threatening the growth of animals and plants, human health and the destruction of ecological environment. There are many researches on remediation of soil heavy metal pollution at home and abroad, but the results are not obvious. The traditional remediation methods of soil heavy metal pollution can not meet the actual needs because of various restrictions, in recent years, Microbial remediation of heavy metals in soil has become a new research field at home and abroad because of its high efficiency and no secondary pollution. Some researches on phytoremediation of soils contaminated by heavy metals have been carried out in the early stage of this project, and some progress has been made in the research, and the effect of remediation is satisfactory. On the basis of the previous study, the soil samples of Yunyang section of the fluctuation zone in the three Gorges Reservoir area, which have better phytoremediation effect, were selected as the object of study. Five strains with removal effects on copper, zinc and cadmium were screened and isolated from the soil samples. Among them, B01 is the strain with Cu2 removal, B02, B03 is the strain with removal of Cd2, B04, B05 is the strain with the effect of removing Zn2. After culture, enrichment and purification, the results were as follows: B01, B02, B04, Pseudomonas flavum, B05, Pseudomonas, B03, B05, B01, B02, B04, B03, and B05, respectively. In the experiment, according to the different pH, temperature, the initial concentration of heavy metal ions and the change of single factor, the effects of different nutrient solution on the removal of Cu2, Cd2 and Zn2 were observed. Among them, strain B01 removed Cu2, strain B02, strain B03 removed Cd2, while strain B01 removed Cu2, strain B02, and strain B03 removed Cd2. Strain B04, B05 removed Zn2. The experimental results showed that the removal rate of heavy metals was first increased and then decreased with pH and temperature of strain B01, which was negatively correlated with the change of initial concentration of Cu2. The results showed that the removal rate of heavy metals was negatively correlated with the initial concentration of Cu2. The curve of removal of Cu2 and initial concentration of Cu2 increased first and then decreased, the removal rate of Cu2 reached the highest value of 70% when pH was at 7, and the removal rate of Cu2 reached to the highest value of 70% at 30 鈩，

本文編號：2444615