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1.
In this paper a comparison is made between the growth and morphology of barred mudskippers (Periophthalmus argentilineatus) from six mangrove forests along the coast of Tanzania. The fish populations from unpolluted sites consisted of different size classes, whereas only small sized fish were present in the polluted Mtoni mangroves. Age estimation based on the examination of otoliths revealed that the mudskippers followed similar growth patterns in all sites with limited pollution. However, the age estimates from the polluted Mtoni site revealed an abnormal growth pattern. The occurrence of unilateral anophthalmia in the Mtoni mudskippers suggested that these fish were affected by pollutants during early development. The study showed that the presence of urban and industrial wastes from Dar es Salaam city, as indicated by isotopic enrichment, correlated with abnormal growth and developmental effects in mudskippers. We hypothesize that pollution might also affect fish species that use the mangroves as a temporary habitat.  相似文献   

2.
Metal concentrations in sediment and in whole tissue of the benthic polychaete Glycera longipinnis collected along the southwest coast of India were analysed. Relative seasonal accumulation of metals (Cu, Pb, Cr, Ni, Zn, Cd, Hg) was studied by categorising the habitat as less polluted or highly polluted based on metal contamination routed through industrial and urban sources. The metal content in tissues varied seasonally in the ranges, Cu: 2.21–27.08 μg·g?1, Pb: 0.06–4.92 μg·g?1, Cr: 1.73–29.20 μg·g?1, Ni: 1.60–4.61 μg·g?1, Zn: 14.72–82.30 μg·g?1, Cd: 0.04–1.38 μg·g?1and Hg: below decetable limits to 0.86 μg·g?1. Concentration of heavy metals was found to be high in the whole body of G. longipinnis pooled from the polluted transects. The results of this study suggest that G. longipinnis may act as a useful biological indicator for heavy metal pollution along the southwest coast of India.  相似文献   

3.
The present study deals with biology, ecology and population dynamics of freshwater turtle Kachuga tentoria and its role as water purifier. The study area Panchnada is the site, where five important national rivers meet together and is preserving an appreciable population of nine species of fresh water turtles. Kachuga tentoria was located at all the sampling stations surveyed by the authors, and hence selected for the present study. Different activities (nesting, incubation, predation and other reproductive aspects), climatic conditions, habitat, population density and morphometric features were worked out in detail. A time bound conservation strategy is needed to save this species from extinction. In situ conservation will be more helpful for the recruitment of the population of this species. It will help in the "hatch and release programme" to clean different polluted national rivers.  相似文献   

4.
交通污染区城市绿化植物硫含量分布   总被引:7,自引:1,他引:7  
为探讨城市绿化植物对交通环境中SO2的响应,以远离城市道路的相对清洁区公园生长的植物为对照植物,采集了广东省被广泛栽种的18种园林绿化植物的不同方位的叶片和树皮样品,用硫酸钡比浊法测定了每种植物样品在交通污染区面向机动车行驶方向、面向人行道方向及相对清洁区的植物样品等不同方位的植物叶片和树皮硫含量,分析了绿化植物在同一株植物的不同生长部位和不同环境中硫含量的分布特征。结果表明,交通污染区所有样品的叶片硫和树皮硫含量均高于相对清洁区的样品。其中,远离工厂的交通污染区生长的同一株植物,离机动车道越近,硫含量越高;靠近工厂的交通污染区的同一植物,离工厂近的部位的植物树皮硫含量高于面向机动车道一侧的植物硫含量。  相似文献   

5.
天津市清静黄河口河岸翅碱蓬的重金属富集特性   总被引:2,自引:0,他引:2  
对天津市清静黄河口河岸生长的翅碱蓬根茎叶及其生长土壤中铜(Cu)、铅(Pb)、镉(Cd)、铬(Cr)、锌(Zn)、砷(As)和镍(Ni)的含量进行了分析.结果表明,这些重金属元素在污染土壤和翅碱蓬各器官中均发生了明显累积,且累积强度不同.在污染土壤中,Cd的累积强度最弱,Zn的累积强度最强,重金属累积强度顺序为Zn>Cu>Pb>Cr>Ni>As>Cd.翅碱蓬叶部积累了大量的As、Ni和Zn,表明翅碱蓬对As、Ni和Zn的吸收和富集能力较强,而对Cu和Pb的吸收和富集能力较弱,迁移累积率顺序为As>Ni>Zn>Cr>Cd>Cu>Pb.污染土壤上生长的翅碱蓬的生物量远低于正常土壤上生长的翅碱蓬的生物量.图1表5参19  相似文献   

6.
This study is to isolate the effluent strain of VAM fungi from polluted soils of sugar mill effluents. Analysis showed that pH and EC was more but the organic matter is less when compared to non-polluted soils. Even though there was low P content that enhances the mycorrhizal infection, the percent of root colonization was less than 75% in polluted study site. The number of VAM propagules and its distribution were also greatly affected due to various factors. Nine different VAM species were isolated and identified from the polluted study site. Using Allium cepa L. as the host plant the efficiency of the native effluent tolerant strains of VAM fungi isolated from the polluted study site was determined. Highest growth rate, high dry weight of gram per plant and increased growth was observed in the order of Glomus intraradices followed by Gigaspora margarita and Glomus fasciculatum. Consequence of the study clearly showed that Glomus intraradices was the efficient strain in sugar mill effluent polluted areas.  相似文献   

7.
The survey of fish fauna in Kaveri River at polluted and unpolluted sites revealed a direct effect on the distribution of fishes in that 14 species were observed in unpolluted site and only 6 species in polluted site. Further, the haemotological parameters like RBC, WBC and haemoglobin content increased in fishes collected from polluted site whereas the organic constituents of muscle decreased in the above fishes when compared to the fishes of unpolluted site. The reason for the above changes is discussed.  相似文献   

8.
A 2-year field study was carried out to determine the impact of kraft pulp-mill effluents on the fish fauna of a shallow-bay system in north Florida (Apalachee Bay, USA). Offshore areas that received kraft-mill effluents (KME) displayed significant increases in color and turbidity and reductions in (benthic) dissolved oxygen compared to a nearby control area. Estuarine and marsh fish assemblages in areas of acute impact were severely reduced in terms of numbers of individuals (N) and species (S). Offshore areas exposed to varying (chronic) levels of KME were characterized by complex interactions that included seasonal variations of impact. A broad offshore area showed reductions in numbers of individuals and species taken per month. However, the cumulative (annual) number of species taken was the same for polluted and unpolluted (control) areas due to a recruitment of relatively rare species in the areas of impact. Such polluted areas showed decreased dominance as well as qualitative differences in species composition compared to control areas. Inshore bay stations that were most severely affected by KME were dominated by the bay anchovy, Anchoa mitchilli. While species richness and species diversity were lower at the highly stressed stations, in other outlying areas of moderate impact (reduced N and S) there were no reductions of such parameters compared to control areas. Thus, species diversity was not an indicator of pollution per se, and was useful only when taken in conjunction with various other parameters. Transition areas (between polluted and unpolluted portions of the bay) showed substantial (although periodic) increases in N, S, and species diversity. Equitability indices were unchanged in polluted portions of the bay. In general, the effects of KME on offshore fish assemblages appeared to be due to a complex combination of habitat alteration, reduced benthic productivity, and individual behavioral reactions. The alterations of fish assemblages were compared to other studies in this area on benthic macrophytes and invertebrates in an effort to assess the usefulness of various indices in studies on the long-term effects of pollution on estuarine and coastal systems. It was found that kraft pulp-mill effluents had a pronounced effect on the benthic standing crop of plants and animals, but that intensive sampling over prolonged periods of time was necessary for an adequate assessment of the problem. Overall, there were some significant changes in the biota such as reduced dominance and productivity in polluted areas that were similar for the various types of organisms sampled.  相似文献   

9.
新乡市公园土壤重金属污染   总被引:3,自引:0,他引:3  
通过对新乡市区6个有代表性公园土壤重金属含量的调查,结果发现市区公园表层土壤Pb、Cr、Cd和Zn的平均含量分别为63.22 mg/kg、91.35 mg/kg、0.57 mg/kg、115.63 mg/kg。以河南省土壤背景值为标准,用内梅罗指数法综合评价,结果表明:6个公园土壤中重金属Cr、Zn为轻度污染;Pb为中度污染;Cd为重度污染。所有公园土壤都存在Pb、Cd和Zn污染。  相似文献   

10.
Microprofiles of oxygen in epiphyte communities on submerged macrophytes   总被引:3,自引:0,他引:3  
Mussels (Mytilus edulis) transferred in net bags from clean to chronically mercury polluted water readily accumulated mercury during an exposure period of three months. Growth of the transplanted mussels had a diluting effect on the mercury concentration, but the absolute weight of mercury uptake increased throughout the entire period, though there was a tendency for decreased efficiency of the removal of mercury per liter of water filtered by the mussels. Mussels were also translocated from polluted to clean (laboratory) water to depurate mercury. The biological half-lives of mercury was 293 d for M. edulis from the chronically polluted area in contrast to only 53 d for mussels from a temporary massive mercury polluted area near a chemical deposit. In both cases about 75% of the total mercury in the mussels was inorganic, and it is suggested that both inorganic and organic mercury species were immobilized in mussels from the long-term mercury polluted area, whereas the immobilization capacity was exceeded in the short-term mercury exposed mussels near the chemical deposit. Very slow elimination of mercury was observed in the deposit-feeding bivalve Macoma balthica from the chronically polluted area, and about 6% of the total mercury was methyl-+phenyl-mercury. This is more than three times lower than found in M. edulis from the same collecting site. A pronounced difference in the mercury speciation (i.e., total mercury, total organic mercury, methyl-mercury and phenyl-mercury) in M. edulis from the two mercury polluted areas is thought to reflect the different character of the mercury pollution in the two areas.  相似文献   

11.
攀枝花市水系沉积物与土壤中重金属的地球化学特征比较   总被引:4,自引:0,他引:4  
水系沉积物和土壤都是表生作用的产物,是环境中污染物质的重要受纳体,但两者在物质来源和受纳污染物方面又有不同。重金属通过不同方式进入到水系沉积物和土壤之中产生污染,对于区域环境具有重要的影响。为了了解攀枝花市水系沉积物和土壤中重金属元素地球化学特征的异同和污染状况,在攀枝花市范围内系统采集了水系沉积物和土壤样品,从环境地球化学角度,应用地球化学方法研究了攀枝花市水系沉积物及土壤中重金属的地球化学特征,应用地质累积指数法评价了污染情况,并对二者进行了比较研究。结果表明,攀枝花市水系沉积物中重金属的含量普遍高于土壤;水系沉积物和土壤中重金属的分布具有相似的特征;水系沉积物中重金属的污染程度高于土壤,但总体上来说,重金属的污染程度较小。两者的污染程度不同是因为接受污染物的方式不同;两者的分布趋势相同,说明具有相同或相近的污染来源。  相似文献   

12.
大型底栖无脊椎动物是河流生态系统的重要组成生物,具有活动范围相对固定、生命周期较长、生活习性相对稳定等特点,可有效指示河流水质和水生态系统健康状况。有关大型底栖生物群落结构特征及其与水环境之间的关系研究一直是河流生态系统的研究热点。底栖动物具有较强的地域性,其群落结构特征受当地的自然环境特征和社会经济发展程度的双重因素影响。为研究典型平原河网地区的底栖动物群落结构及对水环境状况的响应特征,在上海市选取了83个河道断面进行大型底栖动物采样分析,共获取底栖动物20个分类单位(种),其中软体动物10种,环节动物6种,节肢动物4种。上海河道底栖动物群落结构总体呈现结构单一、物种丰富度低、高度耐污性等显著特征,环节动物的栖息密度和出现频率均最高。城市化水平的空间差异性直接影响底栖动物空间分布的异质性,由市区至近郊、远郊,物种数从11种逐渐上升至15种,而栖息密度则由8 776.3个/m2下降至690.3个/m2。底栖动物群落结构的空间分布特征与水质理化指标的空间分布特征具有良好的对应性,水质空间变化导致环节动物和软体动物、节肢动物的空间分布存在一定交错性,耐污性较强的环节动物主要分布在有机污染重、溶解氧低的市区河道断面,而喜清洁环境的软体动物和节肢动物主要分布在水质较好的郊区断面。寡毛纲物种的栖息密度与溶解氧质量浓度呈显著负相关性。  相似文献   

13.
Pollution, Habitat Destruction, and Biodiversity in Poland   总被引:1,自引:0,他引:1  
In the past 50 years, Poland has experienced unprecedented deterioration of the environment and loss of biodiversity. Emissions of toxic gases, such as SO2, have reached 3 to 4 million tons annually, widely affecting flora, fauna, and human health. Almost all surface waters are heavily polluted. More than 75% of the water in the Vistula, Poland's largest river, is unsuitable even for industrial use. Environmental pollution, habitat loss and fragmentation, and industrialization of agricultural lands and forests have contributed to the loss of biodiversity. As many as 2500 plant species may be endangered (≈25% of all species) and approximately 228 (≈2%) have been extirpated from Poland. The largest losses of flora and fauna have occurred in wetland ecosystems. Among vertebrate species, 15 (≈2%) have been lost and more than 210 (another 30%) are endangered. Given the current economic uncertainty, it is difficult to predict future trends in pollutant emissions and their effects on Poland's biological diversity.  相似文献   

14.
15.
Declines in many native fish populations have led to reassessments of management goals and shifted priorities from consumptive uses to species preservation. As management has shifted, relevant environmental characteristics have evolved from traditional metrics that described local habitat quality to characterizations of habitat size and connectivity. Despite the implications this shift has for how habitats may be prioritized for conservation, it has been rare to assess the relative importance of these habitat components. We used an information-theoretic approach to select the best models from sets of logistic regressions that linked habitat quality, size, and connectivity to the occurrence of chinook salmon (Oncorhynchus tshawytscha) nests. Spawning distributions were censused annually from 1995 to 2004, and data were complemented with field measurements that described habitat quality in 43 suitable spawning patches across a stream network that drained 1150 km2 in central Idaho. Results indicated that the most plausible models were dominated by measures of habitat size and connectivity, whereas habitat quality was of minor importance. Connectivity was the strongest predictor of nest occurrence, but connectivity interacted with habitat size, which became relatively more important when populations were reduced. Comparison of observed nest distributions to null model predictions confirmed that the habitat size association was driven by a biological mechanism when populations were small, but this association may have been an area-related sampling artifact at higher abundances. The implications for habitat management are that the size and connectivity of existing habitat networks should be maintained whenever possible. In situations where habitat restoration is occurring, expansion of existing areas or creation of new habitats in key areas that increase connectivity may be beneficial. Information about habitat size and connectivity also could be used to strategically prioritize areas for improvement of local habitat quality, with areas not meeting minimum thresholds being deemed inappropriate for pursuit of restoration activities.  相似文献   

16.
水生甲虫(昆虫纲,鞘翅目)群落结构受多种环境因素的制约.西苕溪中上游流域38个样点共发现水生甲虫12科36个分类单元.优势属是长角泥甲科的Stenelmis属和扁泥甲科的Psephenoides属,出现频度分别为30和22,但有29属的出现频率不大于5.典范对应分析(CCA)表明,鞘翅目群落组成受荫蔽度、总氮、电导率和栖境质量影响最大.样点环境指标聚类结果与CCA结果一致,样点被分为3组.从第1组至第3组,水体中的总氮(2.80→3.52 mg/L)和化学需氧量(14.5→20.29 mg/L)明显上升,荫蔽度(18→6)明显降低.第1组(18个分类单元)和第3组(16个分类单元)的水生甲虫种类组成差异极显著(P<0.01),第2组水生甲虫多样性最高(26个分类单元).Macronychus,Zaitzevia,Scirtes,Stenocolus,Berosus,Laccobius和Ectopria属可作为清洁水体指示生物,Hydrocassis和Ancyronyx属是重污染水体指示生物.图3表4参16  相似文献   

17.
汽车尾气对土壤和蔬菜中铅含量的影响   总被引:19,自引:0,他引:19  
通过对公路边污染区(离公路50m以内)和对照区(离公路100m以外)土壤和蔬菜铅含量的研究发现,在公路边50m以内汽车尾气明显增加了土壤和蔬菜的铅含量;T检验结果表明污染区和对照区总铅含量有显著差异,有效态铅含量则无显著差异,说明土壤总铅转化为有效态铅是一个非常复杂的过程。蔬菜铅含量随蔬菜品种的不同而有较大的差异,污染区的莴笋、大葱铅含量明显高于对照区,对照区的包白菜铅含量高于污染区,这可能与不同蔬菜品种的生理特性有关。土壤铅绝对量的增加与车速、车流量有较大的关系;车速快、车流量大,则铅含量增加明显。蔬菜铅含量的增加受车流量、车速的影响不明显。  相似文献   

18.
燃煤电厂氟污染与治理对策   总被引:4,自引:0,他引:4  
本文以一个包含干湿两种除尘系统的高氟煤源的电厂为例,研究了电厂的氟迁移转化规律和氟污染源对周围环境的影响。并提出了综合治理电厂氟污染的对策。研究表明:湿法除尘系统的氟污染物主要是渣氟、水氟,而干法除尘系统主要是渣氟和气氟;小麦氟含量与大气中氟显著相关;灰场附近的地表水受到灰水的氟污染,部分潜水井受到了灰场渗水的污染,部分灰场土壤受到大气氟污染。  相似文献   

19.
The term critical habitat is used to describe the subset of habitat that is essential to the survival and recovery of species. Some countries legally require that critical habitat of listed threatened and endangered species be identified and protected. However, there is little evidence to suggest that the identification of critical habitat has had much impact on species recovery. We hypothesized that this may be due at least partly to a mismatch between the intent of critical habitat identification, which is to protect sufficient habitat for species persistence and recovery, and its practice. We used content analysis to systematically review critical habitat documents from the United States, Canada, and Australia. In particular, we identified the major trends in type of information used to identify critical habitat and in occupancy of habitat identified as critical. Information about population viability was used to identify critical habitat for only 1% of the species reviewed, and for most species, designated critical habitat did not include unoccupied habitat. Without reference to population viability, it is difficult to determine how much of a species’ occupied and unoccupied habitat will be required for persistence. We therefore conclude that the identification of critical habitat remains inconsistent with the goal of protecting sufficient habitat to support persistence and recovery of the species. Ensuring that critical habitat identification aligns more closely with its intent will improve the accuracy of the designations and may therefore help improve the benefits to species recovery when combined with adequate implementation and enforcement of legal protections.  相似文献   

20.
The removal, alteration and fragmentation of habitat in many parts of the world has led to a loss of biodiversity. Within the prevailing societal limitations the process is not easily reversed. Attempts are being made to minimise the fragmentation of remaining habitat by strategically reversing or managing habitat loss. Although their relative usefulness is a topic of debate among ecologists, habitat corridors are seen as one way of maintaining spatially dependent ecological processes within landscapes where habitat has been seriously depleted. Corridors can only be effective if they significantly contribute to the species sustaining processes of gene flow, resource access or the colonisation of vacant patches. We present a spatial habitat modelling methodology for evaluating the contribution and potential contribution of connecting paths to landscape connectivity. We have developed the spatial links tool (SLT), which maps link value across a region. The SLT combines connectivity measures from metapopulation ecology with the least cost path algorithm from graph theory, and can be applied to continuously variable landscape data. Combined with expert judgement, link value maps can be used to delineate habitat corridors. The approach capitalises on some synergies between ecological relevance and computational efficiency to produce an easily applied heuristic tool that has been successfully applied in NSW Australia.  相似文献   

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