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1.
In Fiji, contamination of the coastal environment by heavy metals is proving to be a real concern. This work reports for the
first time analyses carried out on an extensive basis, to ascertain the extent of anthropogenic contamination by heavy metals
in the <0.063 mm surface sediments of Suva harbour. Sediment samples from 40 sites selected within the harbour were collected
and analysed for five heavy metals. The levels of the metals range from 21.4 to 143.0 ± 0.1 mg/kg Cu, 1.40 to 4.87 ± 0.07 wt.%
Fe, 22.1 to 93.5 ± 0.3 mg/kg Pb, 40.2 to 269.0 ± 0.3 mg/kg Zn and 1.1 to 2.6 ± 0.2 mg/kg Sn. With reference to the pristine
area of the Great Astrolabe, in Kadavu, the acquired data from the harbour are indicative of heavy metal pollution. This could
be attributed to the numerous industrial and commercial activities at Wailada and Walu Bay industrial areas, the municipal
dump located at the Suva foreshore and the Suva wharf. The pollution is further compounded by the high population density
in Suva city. 相似文献
2.
3.
Despite its being highly mineralised, the Hope Mine area has become a residential district. Composite soil samples taken from 91 allotments show values for cadmium: < 2–220 mg kg–1, lead: 6–38,000 mg kg–1, and zinc: 66–40,000 mg kg–1. Water samples from adits contain 52–86 g kg–1 of lead and < 1–2 hg kg–1 of cadmium. The soil contents of cadmium and lead in at least two areas suggest that remedial actions should be considered. Blood lead levels for 33 children aged between ten months and seven years are in the range 5.7–57 g dl–1; haemoglobin levels vary between 9.7 and 12.7 mg dl–1. There is no obvious relationship between Pb and haemoglobin levels. Further geochemical work to define fully the spatial extent of the polluted region and epidemiological studies including intelligence testing to define further the effects of lead on children in this environment would be valuable.To whom correspondence should be addressed. 相似文献
4.
The effect of heavy metal on the observed growth yield (yobs) was observed in batch culture of activated sludge. However, no attention has been paid to quantitatively describe the relationship between heavy metal concentration and yobs so far. In this study, a growth yield model in relation to the ratio of initial heavy metal concentration (Cm) to initial biomass concentration (X 0) was proposed for batch culture of activated sludge, and was verified with experimental and literature data. A significant decline in Yobs was found with the increase of the Cm/X0 ratio. It was clearly demonstrated that for a given initial heavy metal concentration, real strength of heavy metal exerted on unit biomass would be reduced with the increase of initial biomass concentration. This study for the first time revealed that the toxicity of heavy metal to microbial growth should be correlated with the Cm/X0 ratio rather than to Cm only. A concept of effective Cm/X0 ratio, namely (Cm/X0 )50 was then developed for more reasonably and reliably assessing toxicity of heavy metal to microorganisms. 相似文献
5.
The technical feasibility of using a suitable sorbent for the removal of some heavy metal ions from their aqueous solutions was investigated. The scope of the work covers the use of low-class native wool or wool wastes from industrial processes or from recycled woolen textiles for the removal of copper, nickel, cobalt, chromium, and zinc ions from their effluents. The sorption efficiency of the aforementioned metals by wool is in the following order: copper?>?cobalt?=?nickel?>?zinc?>?chromium. The effect of time of sorption, temperature of the effluent, and concentration of metal ions on the rate of sorption was examined. The effect of oxidation or reduction of wool on its sorption power of copper ions is studied. The reduced wool was found to be better than native or oxidised wool in the sorption of copper metal from its effluents. The reuse of wool as metal sorber after elution of the metal, using hydrochloric acid, was also studied. It was found that wool can be reused for sorption after elution of copper up to 25 times of elution; a very limited amount of permanently fixed copper was observed. The use of sufficient woolen layers displays the best way of obtaining an effluent of zero copper content. 相似文献
6.
Evaluating the environmental impacts of an urban wetland park based on emergy accounting and life cycle assessment: A case study in Beijing 总被引:2,自引:0,他引:2
N. DuanX.D. Liu J. DaiC. Lin X.H. XiaR.Y. Gao Y. WangS.Q. Chen J. YangJ. Qi 《Ecological modelling》2011,222(2):351-359
In this paper, emergy accounting (EA) and life cycle assessment (LCA) methods are employed to investigate a typical urban wetland park, the Green Lake Urban Wetland Park (GLUWP) of Beijing, in terms of its environmental and capital inputs, ecosystem services and organic matter yields, environmental support, and sustainability. The LCA method is also used to obtain a quantitative estimation of the environmental impact of discharges during the entire life cycle of the GLUWP. Various emergy-based indices, such as emergy yield ratio (EYR), environmental load ratio (ELR), emergy sustainability index (ESI), net economic benefit (Np), and environmental impacts of process-based LCA, including global warming potential (GWP), eutrophication (EU), nonrenewable resource depletion (RU), energy consumption (EN), acidification potential (AP), photochemical oxidant creation potential (POCP), particulate matter (PM) and wastes (W), are calculated. The results show that the GLUWP has higher proportions of renewable resource input, less pressure on the environment, more environmental support and better ecological and economic benefits, which can be considered as an environment-friendly and long-term sustainable ecological practice, compared with another constructed wetland in Beijing. Meanwhile, the dominant environmental impact is induced by POCP with the construction phase contributing the most on the entire life cycle. It is expected that increasing green area, extensively using environment-friendly materials, optimizing construction techniques and reducing power consumption can promote the sustainability of the GLUWP. 相似文献
7.
After introducing soft defence techniques as an alternative to hard defence techniques, the need is emphasized to consider
the coastal area as an integral system. By recalling the main driving factors for coastal management: conflict resolution,
resilience and sustainability, we logically arrive at the concepts of ecological engineering and ecotechnology, which are
increasingly acknowledged as possible solutions to achieve sustainable use of coastal space as a resource. In this context,
we refer to the principles of self design and of ecosystem conservation.
In order to deal with real situations we are in need of fundamental ‘tools’ for the application of the soft intervention technology
approach. We therefore introduce the concept of physiographic units and develop an initial elaboration for a coastal stretch
and for coastal wetlands. The latter deserve more attention because of the already established practices of ecotechnology,
at least as far as water and soil quality are concerned, but certainly also concerning morphology, especially in the future.
We conclude by briefly discussing how activities undertaken in two research projects currently being conducted under the framework
of the Marine Science and Technology Program of the Commission of the European Communities are expected to contribute to the
concepts introduced here. 相似文献
8.
The levels of heavy metals (Cd, Cr, Ni, Pb, Sb and V) in Sporobulus pyramidalis plant species from an abandoned battery industry environment were determined during the wet and dry seasons as follows: The ranges in metal concentrations during the wet and dry seasons were 0.002, 0.420, 0.036 and 36.10?µg?g?1, respectively. The coefficients of variation for the metals during wet and dry seasons ranged between none to 151.724% and 13.838–214.935%, respectively. The results showed higher levels of the metals in S. pyramidalis during the dry than wet season. Results obtained from both wet and dry season when compared with background values, Federal Environmental Protection Agency and other international standards revealed that the plant species accumulated high levels of these heavy metals which was evident in concentrations exceeding maximum tolerable limits. The health implications of consuming this plant and any other plant or crop within this environment are discussed. 相似文献
9.
以沈阳农业大学棕壤长期定位试验地为研究对象,分别选取不同年限CK、M_2、M4、N_4P_2、M_4+N_4P_2等10个处理的0~20 cm土壤,测定土壤中Cu、Zn、Pb和Cd等重金属的含量.结果表明:随着年限的增长,土壤中Cu、Zn、Pb和Cd的含量均呈现增加的趋势,以施用有机肥M4和Mz及有机肥化肥配施M_4+N_4P_2对土壤中重金属Cu、Zn、Pb和Cd含量影响最为明显,而在无肥对照CK和单施化肥N_4P_2处理下四种元素均有少量增加;几种重金属元素增长的相对大小为:Cd>Cu>Zn>Pb,其中目前Cu含量还未达到国家二级环境质量标准,Cd含量超标应引起足够重视.几种元素的相关分析表明,Cu、Zn之间具有极显著相关性,表明它们的来源具有一定的相关性. u、zn、Pb和Cd等重金属的含量.结果表明:随着年限的增长,土壤中Cu、Zn、Pb和Cd的含量均呈现增加的趋势,以施用有机肥M4和Mz及有机肥化肥配施M_4+N_4P_2对土壤中重金属Cu、Zn、Pb和Cd含量影响最为明显,而在无肥对照CK和单施化肥N_4P_2处理下四种元素均有少量增加;几种重金属元素增长的相对大小为:Cd>Cu>Zn>Pb,其中 前Cu含量还未达到国家二级环境质量标准,Cd含量超标应引起足够重视.几种元素的相关分析表明, 相似文献
10.
海南岛北部潮间带红树林对重金属的累积特征 总被引:2,自引:0,他引:2
对海南岛北部潮间带红树林湿地7种红树植物(根、茎、叶)及其根系沉积物中重金属元素含量进行了分析,结果表明:研究区湿地沉积物中Ni、Cu、Zn、As和Cd的变异系数大于0.50,沉积物中重金属分布很不稳定。其中Cr、Cu、Zn、As和Cd的含量均高于海南水系沉积物背景值,可能存在外源的输入。仅有Pb的含量略低于海南水系沉积物背景值。总体来看,大部分植物显示了对Cd元素的较强的富集能力(BAC〉1),瓶花木对重金属元素的吸收能力总体上要比其他红树植物强一些,木果楝对重金属元素的吸收能力总体上最弱。其中,瓶花木(Scyphiphora hydrophyllacea)对Cr、Zn、As和Cd的吸收能力较强,莲叶桐(Hernandia sonora)对Cr和Ni的吸收能力较强,角果木(Ceriops tagal)对Pb的富集能力较强。角果木(Ceriops tagal)和桐花树(Aegiceras corniculatum)对Cd和Pb的运输能力较强,瓶花木(Scyphiphora hydrophyllacea)对Cu、Zn和Cd的运输能力较强,尖瓣海莲(Bruguiera sexangula)对Cr、Ni、Cd和Pb的运输能力较强,木榄(Bruguiera gymnorrhiza)对Ni、Cu、Cd和Pb的运输能力较强,木果楝(Xylocarpus granatum)对Cr、Zn和Cd的运输能力较强,莲叶桐(Hernandia sonora)对Cr也有较强的运输能力。但此次所研究的红树植物对As元素的运输能力均很弱,建议适量引入适宜在研究区生长并且对As元素富集能力较强的植物。 相似文献
11.
珠江三角洲地区典型菜地土壤与蔬菜重金属分布特征研究 总被引:11,自引:0,他引:11
通过对珠江三角洲地区的广州市、佛山市、江门市和惠州市典型菜地土壤和蔬菜中重金属(Pb、Cr、Cd、As和Hg)含量及其土壤中有效态(Pb、Cr、Cd)含量的调查,分析蔬菜重金属污染状况与土壤重金属含量的相关性,探讨了土壤重金属含量、有效态含量与土壤理化性质的相关性。结果表明,菜地土壤主要受Pb、Cd、Hg污染。Pb、Cd主要以轻度污染为主;而Hg污染在广州市菜地土壤以轻度污染和重度污染为主,佛山市菜地土壤以中度污染和重度污染为主,江门市和惠州市菜地土壤以轻度污染为主。蔬菜主要受Pb、Cd、Hg污染,少数蔬菜受到Cr污染,但并未检测出蔬菜受As污染。蔬菜中重金属含量与土壤中Pb、Cr、Cd的总量、有效态含量之间呈显著正相关关系,与土壤中As、Hg的总量无显著相关性。土壤中Pb、Cr含量与土壤有机质含量、黏粒含量、粉粒含量均达到显著相关。土壤中有效Pb与有效锰含量呈显著负相关关系,土壤中有效Cr含量与土壤粘粒含量、有效铁含量呈极显著正相关关系。 相似文献
12.
The adsorption of heavy metals on soil from the Neihu Landfill Site in Taipei City was investigated in order to assess the groundwater pollution problems. The effects of soil organic matter and the behaviors of organic complexing ligands like EDTA and humic acid to the overall adsorption process were studied and discussed. For explaining the results, the pH value of soil system and the properties of the soil/aqueous interface were chosen as two significant and interacted factors for discussion. The concept of the specific adsorption mechanism was also demonstrated and discussed. The results showed that the complexing ligands existing in soil liquid phase have more influences than natural organic matter does. The competitive sequences of different organic matter contents indicated that organic functional sites preferentially bind with Cu and Cd. The presence of EDTA and humic acid which formed ligandlike complexes will reduce Cd adsorption efficiency. These effects will induce mobility and the fate of heavy metals in soils, such as bioavailability. 相似文献
13.
以无尾河下游漫流区———向海地区沼泽湿地为研究对象,通过对沼泽垂直剖面的精细采样,将放射性核素精确计年与重金属污染评价相结合,进行高分辨率剖析。在对其典型剖面沉积物重金属元素进行Al归一化的基础上,应用上下层比较法、富集系数法和地累积指数法3种评价方法对沉积物重金属污染富集水平及污染时序进行分析比较。结果表明,沼泽湿地沉积物表层已明显富集了重金属元素,达一定污染水平,这显示近20a霍林河流域上、中游人类活动对下游湿地的扰动增强。 相似文献
14.
凡口铅锌矿湿地系统沉积物中重金属的分布 总被引:8,自引:3,他引:8
研究了用于处理凡口铅锌矿选矿废水的宽叶香蒲(Typha latifolia)人工湿地系统沉积物中重金属Pb、Zn、Cu和Cd的分布。沉积物略呈碱性,在各层沉积物中,DTPA-Zn质量分数高于DTPA-Pb质量分数。冬季(11~12月)湿地系统中3个处理池进水口的沉积物结合水中的Pb、Zn、Cu和Cd质量分数与春季(1~3月)的相比较,有显著的差异。湿地处理系统中Pb、Zn、Cu和Cd主要沉积在表层土壤中;但3个处理池入水口和出水口不同深度的沉积物pH值没有显著差异(p<0.05),表明pH值与重金属含量并不存在相关性。 相似文献
15.
Shu-xuan Liang Ning Gao Zhan-chen Li Shi-gang Shen Jianbing Li 《Chemistry and Ecology》2016,32(9):872-883
The accumulation of heavy metals (HMs) in soils is potentially hazardous to human, livestock and plant species. HMs in the combined pollution soils and indigenous plants were investigated in a non-ferrous metal-smelting area. The purpose of this study was to determine the HMs in the contaminated soil and different plant species found growing on it, as well as calculation of bioaccumulation coefficients (BACs). Representative sampling sites were identified according to the land-use types. A total of 12 surface soil samples and 32 plant samples were collected. HMs were analysed by inductively coupled plasma mass spectrometry. The levels of soil pollution were assessed using Nemerow’s synthetical contamination index method. The synthetical index was in the range of 16.81–198.11. This result indicated a heavy burden on local environment. HM concentrations in plants were directly related with soil concentrations. The average BACs of five metals were found in the order of Cd (0.309)?>?Zn (0.178)?≈?Pb (0.160)?>?Cu (0.105)?>?Sb (0.0672). Spontaneous weeds including Chenopodium album Linn, Kochia scoparia and trees of Leuce, Ulmus pumila were deemed HM accumulators. The results provided a practical basis for phytoremediation of HM-contaminated soils using accumulator species. 相似文献
16.
High Cu and Cd pollution in sediments from Sisimiut, Greenland. Adsorption to organic matter and fine particles 总被引:1,自引:0,他引:1
High concentrations of Cu of up to 200 mg/kg, and Cd of up to 4.0 mg/kg, were found in sediments from the aquatic environment around Sisimiut, Greenland. These concentrations are four times higher than the limiting concentration where toxicological effects are expected. The pollution could be linked to human activities in Sisimiut, a link that have not been investigated previously in Greenland. Except from the most polluted samples there was good correlation between heavy metal concentration and organic matter. Also some relationship between fine fraction and heavy metal concentration was observed. 相似文献
17.
This contribution presents an introduction to a series of papers on integrated scientific approaches presented at the San
Feliu Euroconference on transdisciplinary coastal management research. Coastal management is a challenging area for the integration
of social and natural sciences. The papers provide a basis for ongoing cross-disciplinary research. 相似文献
18.
采用静态箱-气相色谱及浮箱-气相色谱法,对闽江河口鳝鱼滩湿地潮间带短叶茳芏(Cyperus malaccensis var.brevifolius)湿地和踩踏造成的裸露湿地N2O通量进行测定。结果表明,短叶茳芏湿地在涨潮前、涨落潮中和落潮后N2O通量差异性极显著(P=0.001〈0.01),不同潮日(7 d内)的N2O通量差异性不显著(P=0.103〉0.05)。涨潮前、涨落潮过程中和落潮后,短叶茳芏湿地平均通量分别为19.48μg.m-2.h-1、12.80μg.m-2.h-1和51.41μg.m-2.h-1,总平均通量为33.1μg.m-2.h-1,表明白天短叶茳芏湿地为N2O的排放源。涨潮前,末次观测短叶茳芏湿地N2O通量最低,多数都为负值,落潮后过2~3 h,短叶茳芏湿地N2O通量出现日最大值。踩踏改变了短叶茳芏湿地N2O通量规律并降低了短叶茳芏湿地N2O通量。涨潮前,裸露湿地N2O平均排放量(27.25μg.m-2.h-1)低于短叶茳芏湿地(42.51μg.m-2.h-1),但差异性不显著(P=0.527〉0.05);落潮后,裸露湿地N2O平均排放量(0.86μg.m-2.h-1)极显著低于短叶茳芏湿地(63.59μg.m-2.h-1)(P=0.006〈0.01)。 相似文献
19.
采用盆栽和田间试验,研究了广州市大坦沙污水处理厂污泥对蔬菜生长发育的影响、污泥中重金属元素在作物体内的累积及在土壤中的残留状况。盆栽结果表明,作物的生长发育和产量与污泥的施用量有一定的关系,施用污泥对于在养分水平较低的砂质土上效果较明显。厂区大田试验还表明,施用污泥对生长周期长的块根类作物的增产效果比茎叶类、果实类作物更显著。作物对Ni的累积量相对为最大,土壤则以Cu、Zn的残留量为最大。在污泥施用量为3×10~4kg ha~(-1)的条件下,作物体内的重金属元素含量均未超过国家食品卫生标准。若污泥施用量为1.5×10~4kg ha~(-1),则其安全施用年限估计为12年。 相似文献
20.
The dynamics of heavy metals in plant-soil interactions 总被引:1,自引:0,他引:1
The effects of soil contamination by heavy metals are studied by a mathematical interaction model, validated by experimental results. The model relates the dynamics of uptake of heavy metals from soil to plants. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality. Data are taken from soil with Cd, Cu and Zn treatments for alfalfa, lettuce, radish and Thlaspi caerulescens, measuring the concentrations in the aboveground biomass of plants. At low concentrations, the effects of heavy metals are moderate, and the dynamics seem to be linear. However, increasing concentrations exhibit nonlinear behaviors. 相似文献