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1.
Environmental Science and Pollution Research - Monitoring of health status and metabolism of dairy cows is essential for modern milk production. At the current level of productivity of dairy cows,...  相似文献   

2.
More than 50% of municipal sewage sludges cannot be used on agricultural land because of their heavy metals content. Therefore, microbial leaching of heavy metal from municipal sludge was studied in a continuously stirred tank reactor without recycling (CSTR) or with sludge recycling (CSTRWR) at residence times of 1, 2, 3 and 4 days. The reactor CSTRWR is supposed to be more efficient for bacterial process due to the recycling of active bacteria from the settling tank to the reactor. The CSTRWR and the CSTR with 1 g litre(-1) FeSO(4).7H(2)O addition were equally efficient because of copper reprecipitation or recomplexation in the settling tank of the CSTRWR. In the CSTR, about 62% of copper and about 77% of zinc were dissolved in 3 days residence time compared to 50% of copper and 64% of zinc in the CSTRWR, if 3 g litre(-1) FeSO(4).7H(2)O was added. Thus with larger amount of substrate, the CSTR was more efficient than the CSTRWR. Residence time and pH were the main factors for zinc solubilization while for copper, the redox potential was also a major factor. The effect of FeSO(4).7H(2)O concentration on bacterial activity to solubilize heavy metals was also studied, increased concentration of FeSO(4).7H(2)O yielded better copper solubilization while it had no effect or a negative effect on zinc. This supports the hypothesis of a direct mechanism for zinc solubilization and of an indirect mechanism for copper solubilization.  相似文献   

3.
4.
Chen CW  Kao CM  Chen CF  Dong CD 《Chemosphere》2007,66(8):1431-1440
The distribution, enrichment, and accumulation of heavy metals in the sediments, especially those at the vicinity of tributary estuaries of Kaohsiung Harbor, Taiwan were investigated. Sediment samples from six locations in the Kaohsiung Harbor were collected quarterly in the period from 2002 to 2005 and characterized for metal content (e.g., Hg, Pb, Cd, Cr, Cu, Zn and Al), water content, organic matter, total nitrogen, total phosphorous, total grease, and grain size. Results showed that metal concentrations varied from 0.58 mg kg(-1) for Cd to 596 mg kg(-1) for Zn. Metal concentrations at the vicinity of river mouths were higher than those at other locations. All heavy metals studied, except Cr, had relatively high enrichment factors and geo-accumulation indices in the estuaries. Moreover, metal concentrations correlated closely to the physical-chemical properties of the sediments, which strongly suggested the influence of industrial and municipal wastewaters discharged from the neighboring industrial parks and river basins. Results would help develop strategies for pollution control and sediment remediation of Kaohsiung Harbor.  相似文献   

5.
4种茄科植物对矿区污染土壤重金属的吸收和富集   总被引:5,自引:0,他引:5  
采集了湖南及江苏8个矿区或冶炼厂周边4种茄科(Solanaceae)植物及其根际土壤,分析了植物及土壤样品中Cd、Cu、Pb、Mn和Zn 5种重金属浓度.结果表明:番茄(Lycopersicon esculentum)对5种重金属可能有着较强的耐性,但不具有超积累的潜力;刺天茄(Solanum indicum)对Mn、...  相似文献   

6.
Bioaccumulation of heavy metals in terrestrial invertebrates.   总被引:9,自引:0,他引:9  
In this literature study, accumulation data of metals in terrestrial invertebrates were collected and compared (Arthropoda and Lumbricidae). Based on total soil concentrations and body concentrations, regression equations were calculated for each metal (Cd, Cu, Pb and Zn) and each taxonomic group. We also tried to find out whether or not accumulation levels of metals in Lumbricidae are representative for all of the studied terrestrial invertebrates. Taxonomic groups could be ordered according to the extent of metal accumulation. Significant differences in accumulation levels of a factor 2-12 were found between taxonomic groups. Overall, metal concentrations were high in Isopoda and low in Coleoptera. The concentrations in Lumbricidae were in between. It should be kept in mind that the data for Lumbricidae were mainly derived from laboratory experiments, while the data for other groups were derived from field studies. The internal Pb, Cd and Cu concentration increased with the soil concentration for most taxonomic groups in the order Pb > Cd > Cu. Body concentrations of Zn were quite constant over a range of soil concentrations. The differences in accumulation level between taxonomic groups show the relevance of including detailed information on feeding behaviour in risk assessment for invertebrate-eating animals.  相似文献   

7.
研究滇池铜绿微囊藻对水体中重金属 (Hg、Cd、Cu、Pb)的富集 ,结果表明 ,该藻对Hg的富集力最强 ,其次为Cd、Cu、Pb。氨基酸含量测定的结果是 :采自滇池水体中的铜绿微囊藻的氨基酸含量比室内培养的低 ,但其所含种类相同  相似文献   

8.
上海市桃浦垃圾填埋场封场植被的重金属吸收和积累特征   总被引:1,自引:0,他引:1  
城市垃圾填埋场的生态修复问题越来越受到重视,选择合适的封场植被对生态恢复至关重要。本研究对上海市桃浦垃圾填埋场的土壤和29种优势植物的重金属含量进行检测,结果显示,该填埋埋场土壤呈现Zn和Cd的中度复合污染。在研究的优势植物中,杨树、雪松和夹竹桃吸收Zn的能力较强,杨树、紫薇、金丝桃吸收Cd的能力较强。荆芥表现为重金属Zn的富集型植物;龙葵表现为重金属Cd的富集型植物;麦冬和狗尾巴草则表现为重金属的根部囤积型植物。可综合选择这些植物用于城市垃圾填埋场的植物修复和植被恢复。  相似文献   

9.

Background  

Open-top chambers were used to study the impact of simultaneous exposure to atmospheric SO2 pollution and heavy metal contamination in soils on the metal contents and productivity of soybean plant.  相似文献   

10.
Environmental Science and Pollution Research - The gill tissue is the main site of metabolic enzymes or compensation, with the kidney tissue playing a supporting role. At the gill tissue, carbonic...  相似文献   

11.
The effects of Cd, Ni, Pb, and Zn on arsenic accumulation by the arsenic hyperaccumulator Pteris vittata were investigated in a greenhouse study. P. vittata was grown for 8 weeks in an arsenic-contaminated soil (131 mg As kg(-1)), which was spiked with 50 or 200 mg kg(-1) Cd, Ni, Pb, or Zn (as nitrates). P. vittata was effective in taking up arsenic (up to 4100 mg kg(-1)) and transporting it to the fronds, but little of the metals. Arsenic bioconcentration factors ranged from 14 to 36 and transfer factors ranged from 16 to 56 in the presence of the metals, both of which were reduced with increasing metal concentration. Fern biomass increased as much as 12 times compared to the original dry weight after 8 weeks of growth (up to 19 g per plant). Greater concentrations of Cd, Ni, and Pb resulted in greater catalase activity in the plant. Most of the arsenic in the plant was present as arsenite, the reduced form, indicating little impact of the metals on plant arsenic reduction. This research demonstrates the capability of P. vittata in hyperaccumulating arsenic from soils in the presence of heavy metals.  相似文献   

12.
随着经济发展,越来越多的重金属通过各种途径进入水体,其中部分通过物理、化学或生物作用在底泥中沉积。在合适条件下,底泥中的重金属又会重新进入水体,危害水生生物以及人类健康。沸石粉、生物炭和镉康等材料常常被应用于底泥中重金属的修复,使重金属中能被生物利用的形态转化为残渣态。通过比较沸石粉、生物炭和镉康对底泥中非残渣态的Cu、As、Cd和Pb的去除效率,发现这3种修复剂均有一定的去除效果,其中沸石粉及生物炭对底泥中非残渣态的重金属去除效果较好。总体来讲,这3种用于底泥非残渣态重金属去除的修复剂的性价比表现为:沸石粉 > 生物炭 > 镉康。  相似文献   

13.

Introduction  

From the metallurgic industry zone of Dambovita County, we harvested and analyzed seven herbaceous plants species (Lolium perenne, Festuca pratensis, Stipa capillata, Agrostis alba, Cynodon dactylon, Luzula campestris, and Agrostis tenuis) to establish the heavy metal accumulation levels in these species.  相似文献   

14.
Kobayashi N  Okamura H 《Chemosphere》2005,61(8):1198-1203
Interactive toxic effects between heavy metals were investigated using a sea urchin (Anthocidaris crassispina) bioassay. An effluent from an abandoned mine showed significant inhibitory effects on embryo development as well as producing specific malformations. The effects on the embryos were reproduced by synthetic polluted seawater consisting of eight metals (manganese, lead, cadmium, nickel, zinc, chromium, iron, and copper) at the concentrations detected in the mine effluent. This indicated that the heavy metals were responsible for the effects observed. Five heavy metals were ranked in decreasing order of toxicity as follows: Cu>Zn>Pb>Fe>Mn. Among these, zinc and manganese could cause malformation of the embryos. From bioassay results using 27 combinations of heavy metals, 16 combinations including zinc could produce specific malformations, such as radialized, exo-gastrulal, and spaceship Apollo-like gastrulal embryos. Zinc was one of the elements responsible for causing malformations and its effects were intensified by the presence of the other metals, such as manganese, lead, iron, and copper.  相似文献   

15.
考察11种丝状真菌在3种重金属(Cr(Ⅵ)、Pb~(2+)、Cd~(2+))胁迫条件下的生长情况,测定重金属对供试菌株的最小抑制浓度(MIC),探讨供试菌株对重金属的耐受性。结果表明,重金属对供试菌株生长的抑制作用随重金属浓度升高而增大,高浓度重金属胁迫条件会改变供试菌株的培养性状。在14d的观察期内,Mucor sp.(菌株号Mu-tea1)对Cr(Ⅵ)表现出较好耐受性,MIC为220mg/L,在此条件下菌落直径为3.1cm,与其他菌株相比有显著性差异(p0.05)。对Cd~(2+)有较好耐受性的菌株有Neofusicoccum sp.(菌株号Nf1172)和Penicilliumsp.(菌株号Pe-soil2),MIC均为18mmol/L,在此条件下菌落直径分别为2.3、2.7cm,与其他菌株相比均有显著性差异(p0.05)。对Pb~(2+)耐受性最好的菌株为Pe-soil2,MIC为18mmol/L,在此条件下菌落直径为4.3cm,与其他菌株相比有显著性差异(p0.05)。研究结果可为下一步利用优势菌株修复环境中重金属污染提供科学依据和研发材料。  相似文献   

16.
Greenhouse and field studies were performed to examine the growth responses and possible phytoremediation capacity towards heavy metals of several Brassicaceae (Brassica alba, Brassica carinata, Brassica napus and Brassica nigra) and Poaceae (durum wheat and barley). Soils used featured total concentrations of Cr, Cu, Pb and Zn largely exceeding the maximum levels permitted by the Italian laws. Different organic amendments were tested such as a compost and the plant growth-promoting rhizobacterium Bacillus licheniformis. In the greenhouse experiment, plant length, leaf area index and shoots dry matter were evaluated periodically for the Brassicaceae examined. Whereas plant length, grains production, weight of 1,000 seeds, ear fertility and tiller density were determined under field conditions at the end of the crop cycle for wheat and barley. In general, the species tested appeared to be tolerant to high heavy metal concentrations in soil, and slightly significant differences were found for all parameters considered. A marked growth increase was shown to occur for Brassicaceae cultivated on compost- and bacillus-amended contaminated soils, with respect to non-amended contaminated soils. With some exception, higher growth parameters were measured for wheat and barley plants cropped from contaminated soils in comparison to non-contaminated soils. Further, bacillus amendment enhanced the length of wheat and barley plants in both non-contaminated and contaminated soils, while different effects were observed for the other parameters evaluated.  相似文献   

17.
黄石市冬/春季大气PM_(10)中重金属形态特征研究   总被引:1,自引:0,他引:1  
采用三级序列提取程序分离黄石市黄石港区、西塞山区、大冶市、阳新县PM10中的不同形态重金属,并使用电感耦合等离子体质谱对分离后液体中8种重金属(Cu、Cd、Zn、Cr、As、Pb、Ni、Co)的含量进行测定。同时,将传统金属生物有效性系数(k)进行加权,从而以重金属生物有效性综合系数(K)直观表征4个区域空气PM10中重金属对人体健康的危害程度。结果表明:(1)As为黄石市主要重金属污染物,冬季西赛山区As的质量分数为85.5%。(2)黄石港区PM10中冬季Cu、Zn、Cd、Pb和春季Cu、Cr、Pb,西塞山区PM10中冬季Cu、Zn、Cd、Pb、Ni、Co和春季Zn、Cd、Cr、Pb、Ni、Co,大冶市PM10中冬季Cu、Zn、Pb、Ni和春季Cd、As、Pb,阳新县PM10中冬季Zn、Cd、As、Pb和春季Zn、Cd、Pb,其k均大于0.2,对当地居民的健康存在潜在风险或风险。综合评价,阳新县冬季和大冶市春季的大气重金属污染较严重,其K分别为0.544和0.340,对人体健康风险较大。  相似文献   

18.
The accumulation of cadmium (Cd) and copper (Cu) in the polychaete Hediste japonica exposed to the mixture of Cd (or Cu) and petroleum hydrocarbons (PHCs) was investigated and compared with that exposed to single Cd (or Cu). The increased bioavailability of Cd or Cu with exposure concentrations resulted in an increase in the accumulation and net accumulation rate of Cd or Cu during single metal exposure. The net accumulation rate of Cd increased, but the net accumulation rate of Cu decreased with exposure time during single metal exposure, suggesting that H. japonica could actively regulate Cu burden in their body by inhibition of absolute uptake or promotion of excretion. The interactions between Cd (or Cu) and PHCs had complicated influences on the net accumulation rate of Cd and Cu in H. japonica under the condition of the binary mixture, which are dependent on their concentration combinations and exposure time.  相似文献   

19.
During the period May 1972–April 1975 the daily average levels of Pb, Zn, Cd, Ba, V, Ni, Mn, Cu, Cr and Fe were routinely determined at fifteen different stations by means of emission spectrography on dust collected on Whatman 41 cellulose filters in a specially designed high volume sampler. The main characteristics of sampling and analysis procedures are described and the most important statistical results for the elements under investigation are summarized. Comparison with similar results obtained by other investigators confirms the average range of the pollution in the country. Future trends in this five year programme are specified.  相似文献   

20.
The transportation,time-dependent distribution of heavy metals in paddy crops   总被引:13,自引:0,他引:13  
Wang CX  Mo Z  Wang H  Wang ZJ  Cao ZH 《Chemosphere》2003,50(6):717-723
Sixteen experimenmtal plots (5 m x 6 m = 30 m2) were designed with four different levels of heavy metals (HMs) concentration in soil. The concentrations of heavy metals in soils, and paddy plant during the different periods of growth were investigated. A relationship between the total HM content in plants and the HM level in soil was found for a wide range of concentrations. The exchangeable fraction of HMs extracted with 1 M MgCl2 solution according to Tessier's method increased correlation with the dosage of supplemented HMs, then decreased as time went on. The time-related variation of exchangeable HMs in soil demonstrated that the amount of effective HMs taken up by paddy differed at various growth phases. The amount of HMs accumulated in different parts of paddy followed the order of root > stem > grain, leaf. The transportation potential of the HMs in paddy in present study followed the order of Zn, Cr > Cd, Cu > Pb. The HM content in root, stem and leaf of paddy plant (dry weight) was low at time of seedling. The concentration in the root increased sharply at time of tillering, decreased thereafter. The concentrations in stem and leaf reached the highest at time of tillering, then decreased, while rose slightly at following time.  相似文献   

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