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1.
Growth of marine planktonic diatoms on inorganic and organic nitrogen   总被引:2,自引:0,他引:2  
A study was conducted to determine if coastal diatoms from eutrophic waters (Werribee, Port Phillip Bay, Australia) are able to grow better than diatoms from oligotrophic waters (Bass Strait, Australia) on organic nitrogen compounds as their principal nitrogen sources. Eight clones of marine planktonic diatoms, belonging to 5 species (Skeletonema costatum, Asterionella japonica, Nitzschia closterium, Coscinodiscus sp., and Fragilaria sp.), were incubated with inorganic (either nitrate or ammonia) or organic (either urea, uric acid, alanine, aspartic acid, glutamic acid, glycine, serine, threonine, or valine) nitrogen sources and growth response was measured under high and low light intensities. All clones grew well on the organic as well as thorganic nitrogen compounds under both light regimes. Intraspecific differences were not great, as no appreciable difference was noted between clones from oligotrophic and eutrophic waters. The two negatively-charged amino acids, aspartic and glutamic acids, were somewhat less effective in supporting growth of some clones than were the other amino acids. Virtually all of the dissolved organic nitrogen (DON) compounds tested were utilizable for algal growth. Further, all clones appeared able to utilize at least some natural DON (uncharacterized) for cell division; in 1980, DON represented 97% of total nitrogen in Bass Strait and 83% of total nitrogen in Werribee waters. The results are consistent with previous findings on algal utilization of certain DON compounds and indicate comparable abilities of cells from oligotrophic and eutrophic coastal waters to assimilate these nutrients.Publication No. 307 in the Ministry for Conservation, Victoria, Environmental Studies Series  相似文献   

2.
以静态实验法研究重金属Cu、Cd、Pb和Zn单独以及两两联合对日本虎斑猛水蚤(Tigriopus japonicus)的急性毒性效应,并分析其是否适宜作为我国海水重金属毒性测试的标准生物.结果显示,单独作用下,cu、Cd、Pb和Zn对受试生物的24 hLC50分别为0.26、0.14、0.40和0.65 mg·L-1,...  相似文献   

3.
We assessed the use of anodic stripping voltammetry (ASV) for in-situ determinations of both total concentration and speciation of dissolved heavy metals (Cd, Cu, Pb and Zn) in acid mine drainage (AMD). In the Kwangyang Au–Ag mine area of South Korea, different sites with varying water chemistry within an AMD were studied with a field portable anodic stripping voltammeter. Anodic stripping voltammetry after wet oxidation (acidification) was very sensitive enough to determine total concentration of dissolved Cd because Cd was dominantly present as ‘labile’ species, whilst the technique was not so effective for determining total Cu especially in the downstream sites from the retention pond, due to its complexation with organic matter. For dissolved Pb, the concentrations determined by ASV after wet oxidation generally agreed with those by ICP-AES. In the downstream samples (pH>5), however, ASV data after wet oxidation were lower than ICP-AES data because a significant fraction of dissolved Pb was present in those samples as ‘inert’ species associated with colloidal iron oxide particles. The determination of total dissolved Zn by ASV after wet oxidation appeared to be unsatisfactory for the samples with high Cu content, possibly due to the interference by the formation of Zn–Cu intermetallic compounds on the mercury coated electrode. In AMD samples with high dissolved iron, use of ultraviolet irradiation was not effective for determining total concentrations because humate destruction by UV irradiation possibly resulted in the removal of a part of dissolved heavy metals from waters through the precipitation of iron hydroxides.  相似文献   

4.
Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cr, Cu, Cd, Pb, Zn, and Hg) was investigated in muscle, gill, and liver in two different fish species seasonally collected in El-Mex Bay (autumn 2004-summer 2005). In order to evaluate the pollution status of the Bay, the concentrations of the selected metals in the labile and total fractions were analysed in sediment samples collected from eight sites in El-Mex Bay during autumn 2004. Also, the Index of Geoaccumulation (Igeo) for the sediment was estimated. The total and labile fractions of the selected metals in sediment samples were 15.2 and 62.8 μg g-1 dw for Cu, 1.8 and 5.0 μg g-1 dw for Cd, 79.1 and 130.3 μg g-1 dw for Zn, 0.2 and 1.2 μg g-1 dw for Hg, 35.8 and 93.0 μg g-1 dw for Pb, and 13.9 and 31.0 μg g-1 dw for Cr. The concentrations of all metals were lower in flesh than those recorded in liver and gill due to their physiological roles. The metal pollution index for fish was calculated. Health hazard calculations for the contaminated sediments and fish consumption were calculated to evaluate the effect of pollution on health.  相似文献   

5.
利用物种敏感性分布(species sensitivity distribution,SSD)方法构建常见重金属元素对海洋生物的SSD曲线,在此基础上,结合实际调查数据,计算了中国近海7种重金属(As、Cd、Cr、Cu、Hg、Pb、Zn)和福建主要海湾6种重金属(As、Cd、Cu、Hg、Pb、Zn)对海洋生物的潜在影响比例(PAF),并分析了各种重金属在相应海区的联合生态风险(msPAF)。结果表明,中国近海水体重金属对海洋生物的生态风险大小顺序为:渤海(20.67%)>黄海(18.39%)>东海(15.94%)>南海(11.26%)。福建主要海湾水体重金属对海洋生物的生态风险大小顺序为:泉州湾(47.44%)>厦门湾(47.16%)>罗源湾(43.03%)>沙埕港(34.65%)>深沪湾(30.34%)>三沙湾(28.64%)>闽江口(20.55%)>诏安湾(20.42%)>兴化湾(18.37%)>湄洲湾(17.24%)。  相似文献   

6.
Estuarine sediments in the<63 μm size fraction were collected from 15 stations within the Tambaraparni River Estuary, located on the east coast of India. The distribution of the heavy metals Cd, Co, Cr, Cu, Ni, Pb and Zn was recorded. Our analysis distinguished two groups of elements. First, Cd, Pb and Zn, which occurred in higher than expected concentrations indicative of pollution, and second, Co, Cr, Cu and Ni, which occurred at background levels. The highest metal concentration found in the study area was for Zn (1200 μ g·g?1), and the lowest was for Cd (0.42 μ g·g?1). It is presumed that river run-off, industrial waters and untreated domestic waters are major contributors to heavy metal pollution in the Tambaraparni River Estuary. The concentrations of heavy metal species in surface sediments (<2 m water depth) of the Tambaraparni Estuary were studied to determine the extent of anthropogenic inputs from catchment areas and to understand anthropogenic effects on geochemical process in this tropical estuarine system.  相似文献   

7.
The present study was conducted to determine the heavy metal contamination in soil with accumulation in plants in waste water irrigated areas. Results revealed that waste water contained lower concentrations of Cr, Zn, Cu, and Pb except Cd (0.03) than the permissible limits prescribed by the World Health Organization. The maximum metal concentrations occurred in Brassica oleracea (Zn 63.80, Cu 12.25, Cr 10.65, Pb 3.63, and Cd 0.56 mg Kg?1).The metal enrichment (EF of Cd 1.9, Cr2.9, Zn 4.8, Cu 6.5, and Pb 15.5) and degree of contamination (CF of Cd 2.9, Cr 2.0, Zn 2.3, Cu 2.7, and Pb 2.2) showed that accumulation of the five toxic metals increased during sewage irrigation as compared with the reference values, other Indian regions and globally. However, based on WHO standards for heavy metal contamination of soil and irrigation water, our data does not ensure safe levels for food.  相似文献   

8.
Reproductive toxicity of metals in calanoid copepods   总被引:2,自引:0,他引:2  
This study investigated the effect of exposure route on metal accumulation, tissue distribution, and toxicity in the marine copepods Acartia hudsonica and A. tonsa. Sublethal toxicity was measured as decreases in egg production, hatching rate, ovarian development and protein (yolk) content of the egg. When algal food, exposed to Hg at 1 nM or Cd at 5 nM resulting in cells containing 34 and 64 nmol metal g-1 dry weight, respectively, was ingested over a 4-h period by copepods, the total copepod body burden increased nine-fold for Hg and two-fold for Cd over background concentrations, and egg production decreased by 50%. Sublethal concentrations of metals were >2 orders of magnitude lower than LC50 concentrations. Hatching rate, ovarian development and egg protein content all decreased following trophic exposure to metals, implying that the process of yolk accumulation (vitellogenesis) was affected. Exposure to dissolved Cd had no effect, but dissolved Hg at concentrations as low as 0.25 nM did affect egg production. Different toxic effects following different exposure routes were related to different metal distributions in the copepods: exposure to dissolved metal resulted in metal deposition in the exoskeleton, whereas exposure to dietary metal resulted in metal deposition in internal tissues. These findings indicate that enrichment of metal concentrations in internal tissues, which occurs primarily after exposure to dietary metal, affects vitellogenesis. The reproduction rate decreases by about 75% at metal concentrations only moderately higher than levels in coastal waters. Toxicity tests involving aquatic animals need to consider effects following uptake by different pathways, including the trophic transfer of metals.  相似文献   

9.
Between 1980 and 1984, plankton was collected for metal analysis during four expeditions in the Baltic Sea. for comparison, samples from adjacent areas of the northeastern Atlantic Ocean were also taken. the mixed net-plankton samples were analyzed by AAS for metals (Al, Cd, Co, Cr, Cu. Fe, Mn, Ni, Pb, and Zn). the results are discussed with regard to spatial and temporal trends and for comparison with data from other authors. Correlations among the contents of the different metals and between the metal contents and 'external factors' including salinity, season, percentage of co-collected phytoplankton, and concentration of dissolved and particulate metals in the water are considered.

There is a tendency for higher metal contents in plankton from the brackish Baltic Sea (Al, Mn and Hg), while other metals (e.g. Cd) show higher levels in samples taken from the marine environment. Except for mercury, no clear correlations could be found between the metal content in plankton and the dissolved concentration of the same metal in the ambient water. Otherwise, the contents of aluminium, iron, manganese and zinc in the suspended particulate matter and in the plankton seem to be partly related to each other.  相似文献   

10.
为了评价电子废物酸解、焚烧活动对当地小流域水体的金属污染,采集了广东省清远市龙塘镇地区泉水、水塘、水库、农灌渠、水田和水井中的水样,分析了各水样中的10种金属含量.研究结果表明,从电子废物酸解、焚烧核心区域的坡谷中采集的泉水受到了较严重的Pb污染,水中Pb浓度达到0.070mg·L-1,高于国家地表水环境质量标准(GB3838-2002)规定的III类水质标准.在酸解作坊边缘一个水塘的水样中检出了浓度分别高达64.82、56.37、2.164、0.200和6.649mg·L-1的Cu、Zn、Cr、Pb和Cd,均大大超过了III类水质标准,其中Cd超标1329.8倍,pH值只有2.05,电导率高达6890μS·cm-1,说明该水塘中的水基本是电子废物酸解活动排放的废水,并且已经通过下渗、地表径流等过程污染了小流域中的其他水体.虽然在农灌渠、水田、水井的水样中未检出超标的重金属浓度,但各种迹象说明,这些水体也已经受到了电子废物回收活动的影响,其中井水中电导率接近400μS·cm-1,远高于其他自然水体.来源于电子废物不当处置的重金属在这些水体中的累积值得关注,今后有必要开展更为持久、全面、系统的监测和研究.  相似文献   

11.
The aim of this study was to assess the use of Osilinus atrata (Gastropoda, Mollusca) as a biomonitor of heavy metals (Cd, Cu, Pb and Zn) within the coastal zone of the Canary Islands. In general, this top-shell snail showed high intraspecific variability in its tissue metal concentrations, which decreased according to the following sequence: Cu≥Zn>Cd≥Pb. In particular, Cd and Zn concentrations were higher in males than in females, whereas Cu concentrations increased slightly with weight, and Pb concentrations decreased. Cd and Cu concentrations showed notable spatial variability; Cd concentrations were higher in the eastern islands (Alegranza, La Graciosa, Lanzarote and Fuerteventura) and La Palma, whereas Cu levels were highest in some western islands (Gran Canaria, La Gomera and El Hierro). The arrival of waters from the African coastal upwelling, the pollution of coastal waters with agricultural fertilisers and the competition for uptake between metals appear to be the likely causes within these patterns of accumulation. In conclusion, O. atrata presents a great potential as a biomonitor of heavy metals, however, more information and further studies are necessary.  相似文献   

12.
Abstract

Terrigenous inputs and sedimentary fluxes of trace metals were studied to understand the metal sources, transport and sinks in the southeastern Taiwan Strait. the major terrigenous metals come from seven major rivers in the southwestern Taiwan, even though significant fractions of most metals were retained in estuaries. the net fluxes of river borne metals contributed from 65% (Pb) to 92% (Fe, Zn) of total inputs. the remainder was attributed to marine sewage discharges (0.6–6.9%) and atmospheric inputs (5.3–31.5%). Sedimentary fluxes of trace metals were spatially variable as a result of derivation from site-specific sedimentation rates and metal distributions in sediments. in spite of imbalance between sources and sinks of trace metals, an accumulation of metals in the sediment of southeastern Taiwan Strait was found for sites close to Taiwan Island. Surface enrichment of metals in near-shore sediments beginning around 1976 was coincident with a time of industrial boom in Taiwan. the metal enrichment hierarchy was found as (Cd, Pb < Cu < Zn < Mn, Fe).  相似文献   

13.
Data on Cd, Pb and Cu concentrations in seawater referring to five years of field studies on the western Mediterranean Sea are reported in order to present a space and time integrated situation on the levels of these metals. Surface total metal concentrations present rather homogeneous distributions between the different areas considered, including the Tyrrhenian Sea. The metal concentrations in three areas affected by natural and industrial wastes are also discussed. The vertical distribution of the dissolved Cd, Pb and Cu in the Alboran Sea seems to be rather homogeneous, both vertically and among the stations chosen between the Strait of Gibraltar and the Island of Alboran.  相似文献   

14.
Heavy metals pollution in aquatic environments is a major problem contributing to human health issues. The study of these pollutants through bioindicators such as the oyster Crassostrea iredalei is important for (1) determining the levels and sources and (2) regulating the quantity of pollutants. The concentrations of cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), and lead (Pb) in tissues of C. iredalei, sediment and surrounding water was measured, and data was analyzed to determine the relationship between sampling periods and between oyster tissue, sediment, and water. The highest concentration of metals in oyster tissue was Zn, followed by Cu, Mn, Cd, and Pb. Concentrations of Cd, Cu, and Zn exceeded the maximum level allowed according to the Malaysian Food Act of 1983, which is equivalent to the WHO recommended levels of heavy metals in organisms used for consumption. The highest metal concentration in sediment was Mn followed by Zn, Pb, Cu, and Cd. Concentrations of heavy metals in surrounding water were Zn, Pb, Cu, Mn, and Cd. There was no correlation between metal concentration in oyster tissue and in sediment for all five metals.  相似文献   

15.
The occurrence of toxic metals in waters is a major health issue. Polluted waters can be cleaned by biosorption, which uses organisms such as algae, bacteria, fungi and plants that adsorb metals. In particular, water hyacinth—Eichhornia crassipes—is a promising biosorbent. Here we tested novel alginate-immobilised water hyacinth beads for the removal of Cu from aqueous solutions. Results show that successful service and regeneration continuous cycles were performed using a packed-bed, flow-through column of fixed internal diameter 1.2 cm, at room temperature and pH 5.1, with variation in initial metal concentration, bed depth and flow rate. The eluant used was 1 % w/v CaCl2 acidified at pH 3. A concentration factor of 12 and elution efficiency up to 98 % were observed in five service and regeneration cycles performed. The equilibrium adsorption capacity of Cu remained almost constant at about 29 mg/g. To conclude, we show for the first time that alginate-immobilised water hyacinth beads can uptake and adsorb Cu very efficiently in a continuous-flow mode, hence highlighting their great potential for removal of toxic metals from aquatic environments.  相似文献   

16.
The present investigation deals with the accumulation of heavy metals in fields contaminated with fly ash from a thermal power plant and subsequent uptake in different parts of naturally grown plants. Results revealed that in the contaminated site, the mean level of all the metals (Cd, Zn, Cr, Pb, Cu, Ni, Mn and Fe) in soil and different parts (root and shoots) of plant species were found to be significantly (p<0.01) higher than the uncontaminated site. The enrichment factor (EF) of these metals in contaminated soil was found to be in the sequence of Cd (2.33) > Fe (1.88) > Ni (1.58) > Pb (1.42) > Zn (1.31) > Mn (1.27) > Cr (1.11) > Cu (1.10). Whereas, enrichment factor of metals in root and shoot parts, were found to be in the order of Cd (7.56) > Fe (4.75) > Zn (2.79) > Ni (2.22) > Cu (1.69) > Mn (1.53) > Pb (1.31) > Cr (1.02) and Cd (6.06) approximately equal Fe (6.06) > Zn (2.65) > Ni (2.57) > Mn (2.19) > Cu (1.58) > Pb (1.37) > Cr (1.01) respectively. In contaminated site, translocation factor (TF) of metals from root to shoot was found to be in the order of Mn (1.38) > Fe (1.27) > Pb (1.03) > Ni (0.94) > Zn (0.85) > Cd (0.82) > Cr (0.73) and that of the metals Cd with Cr, Cu, Mn, Fe; Cr with Pb, Mn, Fe and Pb with Fe were found to be significantly correlated. The present findings provide us a clue for the selection of plant species, which show natural resistance against toxic metals and are efficient metal accumulators.  相似文献   

17.
Cu2+、Cd2+和Cr6+对斑马鱼联合毒性作用和生物预警的研究   总被引:3,自引:1,他引:2  
为了研究重金属对水生生物的联合毒性作用,以斑马鱼为受试生物,采用半静态法,在研究Cu2、Cd2和Cr6+对斑马鱼单一毒性的基础上,以获得的Cu2+、Cd2+和Cr6+的96 h-LC50数据,利用等效应曲线法研究了Cu-Cd、Cu-Cr和Cd-Cr的联合毒性作用,并综合分析环境毒理学指标的测定结果,考察利用斑马鱼作为水...  相似文献   

18.
Trace metal concentrations (Zn, Cd, Pb and Cu) were studied in two different bivalve species of the same age, the mussel Mytilus galloprovincialis, Lmk., and the oyster Ostrea edulis, Linnaeus, which had been grown in the water of Lim Fjord, North West Yugoslavia (Peninsula Istria), i.e. under the same physicochemical conditions. The study offers a realistic view on the metal accumulation ability of oysters and mussels. The distribution of trace metals over the different organs and the edible parts of the mussels and oysters, collected in June 1979, was determined and is discussed in detail. The results are supported by the determination of the trace metal levels in the dissolved state and in the suspended material in the ambient sea water of the bivalves. Concentration factors for zinc, cadmium, lead and copper in the mussels of: 95 000, 9 100, 1 500 and 4 000; and in the oysters of: 95 500, 30 400, 3 400 and 64 500 were found, respectively. The values were evaluated comparing the metal concentration in the bivalve soft part and the dissolved trace metal levels in the adjacent water.  相似文献   

19.
This article presents results on heavy metal (Fe, Mn, Cr, Ni, Cu, Cd, Pb and Zn) speciation in the coastal sediments of Albania. Sediment samples were collected within the framework of the activities of the Interreg Italia–Albania Project, carried out in the Southern Adriatic Sea in 2000–01. This study shows that Albanian coastal sediments are highly influenced by river input, as the decreasing concentrations from coast to offshore confirm. Pb represents an exception of the general trend; meteoric inputs are prevalent for this metal. Ni, Cr, Fe, Zn and Cu correlate significantly and positively in the entire area, indicating a common origin for these metals in the analyzed sediments. All metals result mostly associated to the most refractory phases, which constitute up to 80% of the total concentration. Nevertheless a recent input of Cr, Ni, Cu and Mn can be observed, as the result of mining and industrial activities, in some selected areas, such as the Drin Bay and Durres. Their high concentration in the bioavailable phase can determine toxic effect upon biota.  相似文献   

20.
原海燕  黄苏珍  郭智 《生态环境》2010,19(8):1918-1922
通过野外调查和实地修复铅锌矿污染土壤试验,研究了铅锌矿区排污渠污水及底泥中Pb、Zn、Cu、Cd含量和分布特征以及4种鸢尾属植物马蔺(Iris lactea var.chinensis)、黄菖蒲(Iris pseudacorus L.)、溪荪(Iris sanguinea Donn ex Horn.)、花菖蒲(Iris ensata Thunb.)对Pb、Zn、Cu、Cd的积累能力和土壤修复效率差异。结果表明,离污染源越近,重金属污染越严重。Pb、Zn、Cu、Cd4种重金属均大部分沉积在排污水渠的底泥中,污水中Pb严重污染,超标达120倍,底泥中Pb、Zn、Cu、Cd质量分数分别超标1.5倍、1.7倍、1.6倍和1.7倍。排污渠岸土壤Pb、Zn、Cu、Cd质量分数也明显超过了国家规定的土壤环境质量Ⅱ级标准1~5倍。种植4种鸢尾属植物后,土壤中Pb、Zn、Cu、Cd质量分数有所降低。其中,种植马蔺1个月后土壤Pb、Cu、Cd修复效率分别为8.13%、2.45%和22.3%。黄菖蒲和花菖蒲对Zn的修复效率相对较高。4种鸢尾属植物中马蔺对Pb、Cd的吸收能力最强,马蔺地上部(叶、茎)Pb质量分数达983mg·kg-1,且转运系数大于1,是一种潜在的Pb积累植物,黄菖蒲、溪荪和花菖蒲对Zn的吸收能力较强,且吸收的重金属主要积累在根系。  相似文献   

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