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61.
Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia’s largest anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation. In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between different morphological tissues of the sampled plants reveled the metal concentration in following order roots > leaves. Analyses of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants for pollution monitoring of these metals.  相似文献   
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63.
The wetland macrophyte Bidens laevis possesses suitable cytological characteristics for genotoxicity testing. To test its sensitivity as compared to terrestrial plants species currently in use in standardized assays, Methyl Methanesulfonate (MMS), N-ethyl-N-nitrosourea (ENU) and Maleic Hydrazide (HM) were used. On the other hand, the insecticide Endosulfan (ES) - an environmentally relevant contaminant - was assayed in seeds and two-month old plants. Mitotic Index (MI), frequency of Chromosome Aberrations in Anaphase-Telophase (CAAT) and frequency of Abnormal Metaphases (AM) were analyzed. MH, MMS and ENU caused a significant decrease of the MI. MMS was aneugenic whereas MH and ENU were both aneugenic and clastogenic. ES caused a significant concentration-dependent increase of total- and aneugenic-CAAT in roots and a significant high frequency of AM at high concentrations. Because of its sensitivity to mutagenic substances, B. laevis can be regarded as a reliable and convenient species for genotoxicity assays especially if aquatic contaminants are evaluated.  相似文献   
64.
This research was conducted in the middle Duratón River (Central Spain), in the vicinity of Burgomillodo Reservoir. An industrial effluent enters the river 300 m downstream from the dam. Fluoride and turbidity levels significantly increased downstream from the effluent, these levels being to some extent affected by differential water releases from the dam. The community of submersed macrophytes exhibited slighter responses and, accordingly, lower discriminatory power than the community of benthic macroinvertebrates, this indicating that metrics and indices based on macroinvertebrates may be more suitable for the biological monitoring of water pollution and habitat degradation in dammed rivers receiving industrial effluents. However, in relation to fluoride bioaccumulation at the organism level, macrophytes (Fontinalis antipyretica and Potamogeton pectinatus) were as suitable bioindicators of fluoride pollution as macroinvertebrates (Ancylus fluviatilis and Pacifastacus leniusculus). Fluoride bioaccumulation in both hard and soft tissues of these aquatic organisms could be used as suitable bioindicator of fluoride pollution (even lower than 1 mg F L−1) in freshwater ecosystems. Echinogammarus calvus exhibited a great sensitivity to the toxicity of fluoride ions, with a 96 h LC50 of 7.5 mg F L−1 and an estimated safe concentration of 0.56 mg F L−1. The great capacity of E. calvus to take up and retain fluoride during exposures to fluoride ions would be a major cause of its great sensitivity to fluoride toxicity. It is concluded that the observed fluoride pollution might be partly responsible for the absence of this native amphipod downstream from the industrial effluent.  相似文献   
65.
Goal, Scope and Background One of the burning problems of our industrial society is the high consumption of water and the high demand for clean drinking water. Numerous approaches have been taken to reduce water consumption, but in the long run it seems only possible to recycle waste water into high quality water. It seems timely to discuss alternative water remediation technologies that are fit for industrial as well as less developed countries to ensure a high quality of drinking water throughout Europe. Main Features The present paper discusses a range of phytoremediation technologies to be applied in a modular approach to integrate and improve the performance of existing wastewater treatment, especially towards the emerging micro pollutants, i.e. organic chemicals and pharmaceuticals. This topic is of global relevance for the EU. Results Existing technologies for waste water treatment do not sufficiently address increasing pollution situation, especially with the growing use of organic pollutants in the private household and health sector. Although some crude chemical approaches exist, such as advanced oxidation steps, most waste water treatment plants will not be able to adopt them. The same is true for membrane technologies. Discussion Incredible progress has been made during recent years, thus providing us with membranes of longevity and stability and, at the same time, high filtration capacity. However, these systems are expensive and delicate in operation, so that the majority of communities will not be able to afford them. Combinations of different phytoremediation technologies seem to be most promising to solve this burning problem. Conclusions To quantify the occurrence and the distribution of micropollutants, to evaluate their effects, and to prevent them from passing through wastewater collection and treatment systems into rivers, lakes and ground water bodies represents an urgent task for applied environmental sciences in the coming years. Recommendations Public acceptance of green technologies is generally higher than that of industrial processes. The EU should stimulate research to upgrade existing waste water treatment by implementing phytoremediation modules and demonstrating their reliability to the public.  相似文献   
66.
利用水生植物改善北京动物园水环境的研究初探   总被引:13,自引:0,他引:13  
近年来,北京动物园的水体出现严重的富营养化问题,为了净化水环境,本课题采用了水生植物净化水体的生态工程方法进行了研究。研究结果表明,利用水生植物不仅能净化北京动物园水体,而且还有利于营造水上园林景观和水禽创造适宜的生存环境。从单一水生植物的净化作用上看,水葫芦的净化效果最好,次之为睡莲和野生荷花。人工种植的荷上对较差;多种水生植物的组合更有利于植物在净化作用上的优势互补,从而能始终保持较好的净化效果。此外,试验还发现香蒲的适生水深为0.3-0.4m。  相似文献   
67.
太湖东部湖湾大型水生植物分布对水质的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
调查了太湖东部湖湾(贡湖湾、光福湾、渔洋湾)秋季沉水与浮叶植物的种类组成、覆盖度及水体理化性质,分析了大型水生植物的生长与分布对湖水总氮、总磷、透明度与叶绿素(Chl-a)等水质因子的影响.结果表明,太湖东部不同湖湾大型水生植物的分布状况具有明显差异,其分布频度在4.8%~95.2%,并以马来眼子菜分布频度最高.大型水生植物的生长对水体营养盐含量、理化因子等具有较为明显的影响,水生植物生长区湖水不同形态营养盐含量均低于无水生植物生长区,其总氮与总磷平均含量分别低约39%与51%.此外,蓝藻水华首先会在有水生植物生长的区域堆积,且沉水植物生长优势区蓝藻水华堆积程度要高于浮叶植物生长优势区,表现为该区域Chl-a平均浓度最高,达11.15mg/L,而浮叶植物区Chl-a平均浓度为9.98μg/L,无水生植物区的水华堆积程度最低,其Chl-a平均浓度为7.19mg/L.因此,针对不同水生植物生长区,其水体富营养化治理策略亦不同.  相似文献   
68.
对鄱阳湖南矶山湿地、吴城自然保护区、白沙洲国家湿地公园及鄱阳湖龙口等典型湿地进行沉水植物群落的调查与采样,并测定各样点水样及底泥重金属含量,采用地累积指数法和潜在生态危害指数法对底泥重金属污染进行评价,采用Shannon-Wiener多样性指数和Pielou均匀度指数等方法对研究区沉水植物群落结构进行评价,对水体、底泥重金属含量与沉水植物的生物量、物种多样性等进行Pearson相关性分析,评价鄱阳湖湿地水土环境重金属污染现状,探讨水体与底泥重金属Cu、Pb、Cd等污染物对其水体沉水植物群落的影响。结果表明:各采样点水体与底泥中Cu、Pb、Cd等3种重金属元素中含量最高的为Pb;各样点水体(除白沙洲水体ρ(Pb)外)ρ(Cu)、ρ(Pb)和ρ(Cd)等均未超出地表水环境质量Ⅲ类标准限值,水体重金属含量最高的区域为鄱阳湖东部的白沙洲(ρ(Cu)为50.826μg·L-1,ρ(Pb)为68.660μg·L-1,ρ(Cd)为0.337μg·L-1),最低的区域为鄱阳湖西南部的南矶山湿地(ρ(Cu)为4.316μg·L-1,ρ(Pb)为7.301μg·L-1,ρ(Cd)为0.167μg·L-1)。两种重金属污染评价方法的结果均表明,受纳乐安河下游来水的龙口区域为底泥重金属污染最严重区域;但两种评价方法的结果存在一定差异,地累积指数法评价龙口区域的结果为偏中度或轻度污染,潜在生态危害指数法的评价结果为轻度污染。研究区野外调查中共发现11种沉水植物,隶属7科9属,其中南矶山湿地的沉水植物物种多样性较丰富,但其物种分布的均匀度较低,水体与底泥重金属含量与其水体中沉水植物的生物量或物种多样性间无显著相关性。  相似文献   
69.
滨海地区湿地重建的生态工程范例   总被引:2,自引:0,他引:2  
在天津泰达区盐田上通过淡水浸泡、消浪墙构建、土壤更换、水生植物引种等措施,重建了湿地生态系统的结构。结果表明,人工湿地在初期阶段是成功的。  相似文献   
70.
Maret, Terry R., Christopher P. Konrad, and Andrew W. Tranmer, 2010. Influence of Environmental Factors on Biotic Responses to Nutrient Enrichment in Agricultural Streams. Journal of the American Water Resources Association (JAWRA) 46(3):498-513. DOI: 10.1111/j.1752-1688.2010.00430.x Abstract: The influence of environmental factors on biotic responses to nutrients was examined in three diverse agricultural regions of the United States. Seventy wadeable sites were selected along an agricultural land use gradient while minimizing natural variation within each region. Nutrients, habitat, algae, macroinvertebrates, and macrophyte cover were sampled during a single summer low-flow period in 2006 or 2007. Continuous stream stage and water temperature were collected at each site for 30 days prior to sampling. Wide ranges of concentrations were found for total nitrogen (TN) (0.07-9.61 mg/l) and total phosphorus (TP) (<0.004-0.361 mg/l), but biotic responses including periphytic and sestonic chlorophyll a (RCHL and SCHL, respectively), and percent of stream bed with aquatic macrophyte (AQM) growth were not strongly related to concentrations of TN or TP. Pearson’s coefficient of determination (R2) for nutrients and biotic measures across all sites ranged from 0.08 to 0.32 and generally were not higher within each region. The biotic measures (RCHL, SCHL, and AQM) were combined in an index to evaluate eutrophic status across sites that could have different biotic responses to nutrient enrichment. Stepwise multiple regression identified TN, percent canopy, median riffle depth, and daily percent change in stage as significant factors for the eutrophic index (R2 = 0.50, p < 0.001). A TN threshold of 0.48 mg/l was identified where eutrophic index scores became less responsive to increasing TN concentrations, for all sites. Multiple plant growth indicators should be used when evaluating eutrophication, especially when streams contain an abundance of macrophytes.  相似文献   
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