摘要
本论文首先通过滇池底泥中基础数据的研究,得到滇池底泥的污染特点,并主要结合潜在生态危害指数评价法及地质累积指数法比较有效地综合评价现代滇池底泥的污染程度;其次,利用改进的BCR分级提取方法分级提取滇池底泥中重金属存在的4种形态,并通过不同形态的分析来解释重金属释放的原理;接着,采用滇池底泥提取腐殖酸(HA),实验中通过加入不同浓度的HA溶液,分析HA对于重金属释放的影响;然后,采用雷磁数据采集软件,使用类似于络合滴定的方法,通过铜离子选择性电极测定溶液中铜离子的电导率来分析铜离子和HA之间的相互作用机理;最后,使用了与HA与铜离子络合相同的方法,简便快捷地得到滇池底泥对于Cu的络合数据。
研究结果表明:
(1)滇池底泥重金属污染依照潜在生态污染评价法计算,可以看出滇池底泥中重金属对于环境的潜在污染以Cd为最重,最轻的为Zn,并且北部比南部更易发生底泥重金属的二次污染。滇池底泥重金属污染按照地质累积指数方法计算,可以看出,Pb和Cd的污染比较严重。Cu与Zn的污染较轻。结合两种方法,可以得出,滇池底泥中,Cd是主要的污染问题,Cu、Zn和Pb的污染对于滇池的影响较小。
(2)从滇池底泥中重金属BCR形态分布可以看出,滇池底泥从北至南,有效态(除残渣态以外的其他形态之和)逐渐减少,残渣态逐渐增加。有效态是在底泥中起到主要作用的部分,残渣态可以比较稳定的存在于底泥中,而有效态可以比较容易在环境中发生物理、化学、生物等作用。
(3)实验研究表明,HA浓度的变化对于Pb的释放影响最大,滇池底泥中有机质含量较高,这种外在条件,有利于滇池底泥中Pb的释放。Cd的污染是滇池底泥重金属污染的主要问题。结合实验中HA浓度变化对于Cd的释放的影响发现,HA浓度的加大,.加强了底泥中Cd的释放能力,但从北至南,Cd的释放率降低,可能与底泥的.特性、采用的HA的性质有关。
(4)HA的浓度变化对于重金属存在一定的影响。HA浓度增加,重金属释放量增加。同时,HA的浓度变化对于重金属释放的影响也根据研究地点的不同而不尽相同。
(5)铜离子溶液与不同浓度HA溶液进行络合时,随着HA浓度增加,会使得铜离子的络合量增加,铜离子会稳定地与HA螯合。底泥与铜离子的络合实验中,有机质含量较高的草海中心铜离子的络合量最大,说明底泥中有机质含量越高,重金属的释放作用就越小。
上述研究结果初步反映了滇池底泥中Cu、Zn、Pb、Cd等重金属的空间分布和含量分布状况,可为评估滇池底泥重金属污染提供依据;同时,以滇池底泥实际样品为对象,通过实验室条件实验,研究探讨了底泥中重金属释放的机理及主要影响因素,可以为治理滇池底泥重金属污染提供依据。
In this paper, Firstly, through the basic data research of the sediment from Dianchi Lake, the pollution characteristics were presented. Mainly with the potential ecological risk indices method and geological cumulative index method, the sediment pollution in current Dianchi Lake was effectively assessed. Secondly, using improved BCR extraction method, four different forms of heavy metals in sediment from Dianchi Lake was extracted and the results can be used to analyze the principles of the release of heavy metals and then the humic acid was extracted (HA) from the sediment of Dianchi Lake. Through adding different concentrations of HA solutions, the impact of HA on the release of heavy metals was analyze. Then, with the use of ray magnetic data acquisition software and the similar method of complexometric titration, combined with the conductivity determination of copper ions in the solution by the copper ion selective electrode, the mechanism of copper ions and HA was analyzed. Finally, using the same method of HA and copper ions, it is easy to get the Cu complexometric data in the sediment from Dianchi Lake.
Research results show that:
(1) According to the potential ecological pollution evaluation method it could be concluded that Cd was the most serious pollution source while Zn was lightest in the terms of the potential impact of heavy metals in the sediment from the Dianchi Lake on the environment. In the north it was easier to be secondary pollution of heavy metals in the sediment than that in the south. With the geological cumulative index method it was presented that the pollution of Pb and Cd was more serious than Cu and Zn. Combining the two methods it could draw, Cd was the main pollution problem in the sediment from Dianchi Lake while Cu, Zn and Pb pollution was lighter.
(2) With the BCR distribution of heavy metals in the sediment from Dianchi Lake, it indicated that the effective form (the other froms except the residual form) decreased from north to south. On the contrary, the residual state gradually increased. The effective form was the main role played in the sediment, which was easy to come about the physical, chemical and biological reaction. And the residue state was stabilized in the sediment.
(3) According to the experiment results, it showed that the influence of the changes of HA concentrations on the Pb release was greatest and the content of organic matter in the sediment was high, which were helpful to the Pb release. It was the main problem of Cd pollution in the sediment. Combining the influence of the changes of HA concentrations on the Cd release in the experiments, it indicated that with the increasing concentrations the ability of Cd release was increased. But from north to south the rate of Cd release reduced, which was maybe affected by the properties of sediment and the nature of the HA adopted.
(4) The changes of HA concentrations could have a certain influence on the heavy metals. with the increasing concentrations of HA, the release of heavy metals also increased. At the same time, the influence of the changes of HA concentrations on the release of heavy metals varied with the different research points.
(5) During the complexation of copper ions and HA of different concentrations, with the increasing concentrations of HA, the complexation quantity of copper ions would increase and the copper ions would be chelating with HA. In the complexation experiments of the sediment and copper ions the complexation quantity was highest in the Caohai center with the high organic matter content, which indicated that with the higher organic matter content the release of heavy metals was lower.
With the research results, the space distribution and content distribution of the heavy metals such as Cu Pb Zn Cd in the sediment from the Dianchi Lake was presented, which were served as basis for the evaluation of heavy metal pollution in the sediment from the Dianchi Lake. Meanwhile with the combination of the actual samples of the sediment from the Dianchi Lake and the experiments in the laboratory, the mechanism of the release of heavy metals and the main influence factors were discussed, helpful for the treatment of heavy metal pollution in the sediment from the Dianchi Lake.
引文
1本论文中以后的腐殖酸均用HA表示
[1]郝晓蕾,杨常亮,魏勤等.滇池污染现状的综合评价及分析[J].云南大学学报(自然科学版).1998(20):589-592
[2]吕小玲,徐清艳.滇池污染现状、趋势及其综合防治对策[J].闽江学院学报.2002,23(2):109-111
[3]李益敏,彭永岸,王玉朝等.滇池污染特征及治理对策[J].云南地理环境研究.2003,15(4):32-38
[4]彭永岸,朱彤.滇池污染的成因及其治理新方案[J].地球信息科学.2003,1:16-21
[5]马巍,李锦秀,田向荣等.滇池水污染治理及防治对策研究[J].中国水利水电科学研究院学报.2007,5(1):8-14
[6]王玉朝,彭永岸,李益敏.滇池水体污染和治理的特点[J].地域研究与开发.2004,23(1):88-92
[7]方涛,敖鸿,刘剑彤等.滇池水体理化环境状况时空分布格局研究[J].水生生物学报.2004,28(2):124-130
[8]强继红.滇池水环境污染的工程治理综述[J].云南地理环境研究.2002,14(1):61-66
[9]王喜.滇池面源污染现状调查与控制途径[J].云南农业.2008,12:28-29
[10]芳琳.昆明滇池环境的污染成因与治理分析[J].中国科技产业.2006
[11]黄永泰.滇池污染状况及其综合治理[J].环境污染与防治.1999,21(4):28-31
[12]徐晓梅,张琨玲.影响滇池入湖污染物总量变化的主要因素分析[J].云南环境科学.2004,23(4):42-44
[13]陈建军.滇池主要入湖河流水质分析[J].云南农业大学学报.2005,20(4):569-571
[14]肖青.滇池水环境的现状成因及对策[J].水利科技与经济.2005,11(1):26-28
[15]滑丽萍,华珞,高娟等.中国湖泊底泥的重金属污染评价研究[J].土壤.2006,38(4):366-373
[16]王晓,韩宝平,丁毅等.京杭大运河徐州段底泥重金属污染评价[J].能源环境保护.2004,18(3):47-49
[17]殷效玲,郑祥民.上海市苏州河支流——桃浦河底泥重金属的污染特征[J].安全与环境学报.2001,1(1):19-22
[18]刘艳平,李炼,李忠魁,何莉芳,郑杰.底泥重金属铅对鲤鱼红细胞遗传物质的损伤[J].实用预防医学.2003,10(3):333-335
[19]方涛,肖邦定,张晓华等.曝气对两种不同类型沉积物中重金属释放的影响[J].中国环境科学.2002,22(4):355-359
[20]周孝德,黄廷林,唐允吉.河流底流中重金属释放的水流紊动效应[J].水力学报.1994,11:22-30
[21]姚志刚,鲍征宇,高璞.洞庭湖沉积物重金属环境地球化学[J].地球化学.2006,35(6):629-638
[22]张鑫,周涛发,杨西飞等.河流沉积物重金属污染评价方法比较研究[J].合肥工业大学学报(自然科学版),2005,28(11):1419-1423
[23]徐燕,李淑芹,郭书海等.土壤重金属污染评价方法的比较[J].安徽农业科学.2008,36(11):4615-4617
[24]霍文毅,黄风茹,陈静生等.河流颗粒物重金属污染评价方法比较研究[J].地理科学.1997,17(1):81-86
[25]丁喜桂,叶思源,高宗军.近海沉积物重金属污染评价方法[J].海洋地质动态.2005,21(8):31-36
[26]刘哲民.宝鸡土壤重金属污染及其防治[J].干旱区资源与环境.2005,19(2):101-104
[27]罗良荣,梁朝玉.右江百色城河段水质现状及变化趋势分析[J].云南环境科学.2006,25(增刊):97-99
[28]张泉荣,吴朝明.梅梁湖底泥重金属污染评价方法探讨[J].江苏水利.2003,9:32-33
[29]周康民,汤志云,黄光明等.土壤中重金属形态分析方法研究[J].苏州地质.2007,31(3):165-175
[30]周笑怡.重金属形态分析方法学研究[硕士学位论文].上海:上海交通大学,2008
[31]黄光明,周康民,汤志云等.土壤和沉积物中重金属形态分析[J].土壤.2009,41(2):201-205
[32]冯素萍,刘慎坦,杜伟等.利用BCR改进法和Tessier修正法提取不同类型土壤中Cu、Zn、Fe、M n的对比研究[J].分析测试学报.2009,28(3):297-300
[33]Tessier A, Campbell pgc, Bissonm. Sequential extracti on procedure for the specificati on of particulate trace metals[J]. Anal Chem,1979, (51):844-850
[34]Forst Neru. Metal polluti on in aquatic environment[M]. Second Editi on. Berlin:Sp ringer-Verlag,1981
[35]Quevau Viller P, Rauret G, Griepnk B. Single and sequential extracti on in sedi ments and soils, Intern[J]. Environ Anal Chem.1993,51:231-235
[36]M.B.Arain, T.G.Kazi, M.K.Jamali. Time saving modified BCR sequential extraction procedure for the fraction of Cd,Cr,Cu,Ni,Pb and Znin sediment samples of polluted lake [J]. Journal of Hazardous Materials.2008,160:235-239
[37]Muhammad B.Arain, Tasneem G.Kazi, Muhammad K.Jamali. Speciation of heavy metals in sediment by conventional, ultrasound and microwave assisted single extraction methods:A comparison with modified sequential extraction procedure [J]. Journal of Hazardous Materials.2008,154:998-1006
[38]Serife Tokalioglu, Senol Kartal, Latif Elci. Determination of heavy metals and their speciation in lake sediments by flame atomic absorption spectrometry after a four-stage sequential extraction procedure [J]. Analytica Chimica Acta.2000,413:33-40
[39]G.Perin, R.Fabris, S.Manente. A Five-Year Study On The Heavy-Metal Pollution Of Guanabara Bay Sediments (Rio De Janeiro, Brazil) And Evaluation Of The Metal Bioavailability By Means Of Geochemical Speciation[J]. Wat.Res.1997,31(12): 3017-3028
[40]M.B. Alvarez, M.Garrido, A.GLista and so on. Three-way multivariate analysis of metal fractionation results from sediment samples obtained by different sequential extraction procedures and ICP-OES[J]. Analytica chimicaacta.2008,620:34-43
[41]Douglas G.Klarup. The influence of oxalic acid on release rates of metals from contaminated river sediment[J]. The Science of the Total Environment.1997,204:223-231
[42]AdilElik. Ultrasonic-assisted leaching of trace metals from sediments as a function of pH[J]. Talanta.2007,71:790-794
[43]ShenyuMiao, R.D.DeLaune, A.Jugsujinda. Influence of sediment redox conditions on release/solubility of metals and nutrients in a Louisiana Mississippi River deltaic plain fresh water lake[J]. Science of the Total Environment.2006,371:334-343
[44]C.Lors, C.Ti□reau, A.Laboudigue. E□ects of bacterial activities on the release of heavy metals from contaminated dredged sediments[J]. Chemosphere.2004,56:619-630
[45]BarbaraA.Butler. Effect of pH,ionic strength,dissolved organic carbon,time,and particle size on metals release from mine drainage impacted streambed sediments[J]. Water research].2009,43:1392-1402
[46]Jacqueline Eggleton, KevinV.Thomas. A review of factors affecting the release and bioavailability of contaminants during sediment disturbance events [J]. Environment International.2004,30:973-980
[47]C.Christophoridis, D.Dedepsidis, K.Fytianos. Occurrence and distribution of selected heavy metals in the surface sediments of Thermaikos Gulf,N.Greece. Assessment using pollution indicators[J]. Journal of Hazardous Materials.2009,168:1082-1091
[48]M.Maanan, B.Zourarah, C.Carruesco and so on. The distribution of heavy metals in the Sidi Moussa lagoon sediments(Atlantic Moroccan Coast)[J]. Journal of African Earth Sciences.2004,39:473-483
[49]F.M.Tack, O.W. J. J.Callewaert, M.G.Verloo. Metal solubility as a function of pH in a contaminated, dredged sediment affected by oxidation)[J]. Environmental Pollution.1996, 91(2):199-208
[50]P.Avila-Pereza, M.Balcazar, G.Zarazua-Ortega and so on. Heavy metal concentrations in water and bottom sediments of a Mexican reservoir[J]. The Science of the Total Environment.1999,234:185-196
[51]C.Lors, C.Ti□reau, A.Laboudigue. Effects of bacterial activities on the release of heavy metals from contaminated dredged sediments[J]. Chemosphere.2004,56:619-630
[52]ClareA.Atkinson, DianneF.Jolley, StuartL.Simpson. E□ect of over lying water pH,dissolved oxygen,salinity and sediment disturbances on metal release and sequestration from metal contaminated marine sediments [J]. Chemosphere.2007,69:1428-1437
[53]Luca Giorgio Bellucci, MauroFrignani, DanielePaolucci and so on. Distribution of heavy metals in sediments of the Venice Lagoon:the role of the industrial area[J]. The Science of the Total Environment.2002,295:35-49
[54]黄廷林.水体沉积物中重金属释放动力学及试验研究[J].环境科学学报.1995,15(4):440-446
[55]李鱼,刘亮,董德明等.城市河流淤泥中重金属释放规律的研究[J].水土保持学报.2003,17(1):125-127
[56]黄廷林,沈晋.环境化学条件对水体沉积物中重金属释放影响的研究述评[J].陕西机械学院学报.1993,9(4):285-292
[57]蔡金娟,史衍玺.不同腐殖酸组分对湖泊沉积物中重金属释放的影响[J].水土保持学报.2006,20(1):108-185
[58]李晶,许蕾,王道涵.不同螯合剂对土壤中重金属释放特征的影响[J].辽宁大学学报.2008,35(3):283-285
[59]文湘华.乐安江沉积物酸碱特性及其对重金属释放特性的影响[J].环境化学.1996,15(6):510-515
[60]文湘华,Herbert E.Allen.乐安江沉积物酸可挥发硫化物含量及溶解氧对重金属释放特性的影响[J].环境科学.1997,18(4):32-34
[61]吕兴娜,刘春.柴河水库沉积物中重金属释放的静态实验[J].辽宁城乡环境科技.2001,21(2):40-41
[62]邹海明,邹长明,林平等.土壤中酸可提取态重金属释放特征研究[J].农业资源与环境科学.2006,22(6):404-406
[63]陈慧,蒋煜峰,袁建梅等.污灌土壤中Cu、Cd、Pb、Zn形态影响的研究[J].第二届全国环境化学学术报告会论文集.427-429
[64]彭张兴,张征,李坚.滇池污染状况及对策建议[J].环境科学与管理.2009,34(8):29-32
[65]邵晓华.云南滇池底泥重金属元素分布规律研究[D].南京:南京师范大学,2003
[66]袁国林,贺彬.滇池流域地理特征对滇池水污染的影响研究[J].环境科学导刊.2008,27(5):21-23
[67]李志杰.滇池流域资源环境人口承载力研究[J].昆明师范高等专科学校学报.2008,30(2):41-44
[68]薛传东,刘星,魏海霞等.滇池近代沉积物的元素地球化学特征及其环境意义[J].岩石矿物学杂志.2007,26(6):582-590
[69]于银亭,李培泉,吴润.昆明滇池沉积速率的测定[J].海洋与湖沼.1996,27(1)41-45
[70]唐厚全,赵祥峰,张璜.不同粒径底泥沉积物中重金属污染特征研究[J].绿色话题.2005,6:44-45
[71]王崇臣,王鹏.pH值对土壤中Pb、Cd释放量的影响[J].安徽农业科学.2009,37(5):2170-2171
[72]杨丽莉,张登峰,曾向东.沉积物中重金属释放规律研究[J].安徽农业科学.2007,35(27):8630-8631
[73]方涛,刘剑彤,张晓华.河湖沉积物中酸挥发性硫化物对重金属释放的影响[J].环境科学境科学学报.2002,22(3):324-328
[741莫美仙,张世涛,叶许春.云南高原湖泊滇池和星云湖pH值特征及其影响因素分析[J].农业环境科学学报.2007,26(增刊):269-273
[75]杨逢乐,金竹静.滇池北岸河流水环境污染现状及防治对策研究[J].环境科学导刊.2008,27(6):43-46
[76]彭丹,金峰,吕俊杰等.滇池底泥中有机质的分布状况研究[J].土壤,2004,36(5):568-572
[77]刘恩峰,沈吉,朱育新.重金属元素BCR提取法及在太湖沉积物研究中的应用[J].2005,18(2):57-60
[78]周吉峙.对滇池底泥重金属不同时间和不同底泥深度的分布特征[D].上海:上海大学,2004
[79]李仁英,杨浩,王丽等.滇池沉积物中重金属的形态分布特征[J].土壤(Soils).2008,40(2):264-268
[80]潘波.土壤有机质的存在形式及对菲的吸附特征[D].北京:北京大学,2005
[81]陈盈,颜丽,关连珠等.不同来源腐殖酸对铜吸附量和吸附机制的研究[J].土壤通报.2006,37(3):479-481
[82]王晶,张旭东,李彬等.腐殖酸对土壤中Cd形态的影响及利用研究[J].土壤通报.2002,33(3):185-187
[83]李光林.腐殖酸与几种重金属离子的相互作用及影响因素研究[D].重庆:西南农业大学,2002