Effects of heavy metal pollution on the ecological and biological characteristics of common chernozem

A detailed comprehensive study on the effects of heavy metals on the biological activity and other characteristics of common chernozem of the southern European facies was performed. This involved the analysis of various microbiological and biochemical indices characterizing soil biological activity, their dynamics, a set of several metals and their different chemical forms, and a wide range of metal concentrations in the soil. New important aspects of the effects of heavy metals on biological processes in the soil were revealed. An integral method was proposed for assessing changes in the total biological activity of the soil on the basis of informative indices used in the monitoring, diagnosis, and indication of soils polluted with heavy metals. Geographic trends in changes of soil resistance to heavy metal pollution were analyzed within the common chernozem subtype and by comparing chernozem with other soils.     

The ecosystem of the Black Sea port of Novorossiysk under conditions of heavy anthropogenic pollution

Ecosystem structure and functioning have been studied in the polluted water area of the Novorossiysk port. It has been shown that communities of phytoplankton, zooplankton, ichthyoplankton, and zoobenthos are inhibited because of chronic exposure to anthropogenic stress. The food web is disturbed, and microheterotrophs (bacteria and protists) are the main functional component of the ecosystem. Water eutrophication and sulfide pollution of bottom sediments are the main factors responsible for ecosystem degradation in the port of Novorossiysk.     

Understanding the dynamics of heavy metals in a freshwater ecosystem through their toxicity and bioavailability assay

The current study investigates on correlating the heavy metal contamination, its distribution, and the human health risk associated with all three components of an aquatic ecosystem. For this purpose, water, sediment, and fish samples (three species, notably Notopterus notopterus, Clarias batrachus, and Channa striata) from Deepor Beel were considered, and their heavy metal contamination and distribution were determined. The corresponding health risks were then evaluated for six different heavy metals; Cr, Cd, Fe, Mn, Cu, and Pb. Pb and Mn were found to significantly impact the non-carcinogenic human health risks for the water column. Simultaneously, Cd was considered to possess the highest potential for both carcinogenic and non-carcinogenic health effects in the sediment column. Cd also played a critical role in the fish samples' bioaccumulation factor, with the liver showing the maximum bioaccumulation potential. Furthermore, children were found to have considerably higher effects (both carcinogenic and non-carcinogenic) than adults. Finally, the sediment column was found to substantially contribute to the bioaccumulation factor in the fish biota, compared to the water column. The results of this investigation will thus prove consequential in designing, monitoring and restoring aquatic ecosystems.

     

Effect of heavy metal pollution on plant communities of the Tanalyk River,the Bashkir Transural region

Geobotanical analysis of aquatic and wetland plant communities of the Tanalyk River has been performed in the zone of impact from the abandoned Kul-Yurt-Tau pyrite mine. The results show that pollution of the river with highly mineralized runoff leads to a decrease in the β-diversity and synthetic characteristics of plant communities (α-diversity, total coverage, and herb layer height) and in the aboveground phytomass of dominant species.     

A survey of heavy metal deposition in Nigeria using the moss monitoring method

The bioaccumulation of Sb, Sn, As, Fe, Ni, Mn, Pb, Cu, and Zn in mosses from polluted and unpolluted areas of the southern parts of Nigeria is presented. Results of the moss samples show strong variations in the concentration of metal ions with type of sampling sites. The concentration of accumulated heavy metals also differs in various moss species from the same biotope. Bryidae mnium is a better accumulator of heavy metals than Tetraphidae tetraphis, as evidenced from the interspecies calibration between the two moss samples.     

Industrial pollution reduces the effect of trees on forming the patterns of heavy metal concentration fields in forest litter

An analysis is made of the effect of large spruce and birch trees on the spatial pattern of the fields of heavy metal concentrations (Cu, Pb, Cd, Zn) and pH in the forest litter formed in tree stands exposed to long-term pollution with emissions from the copper smelter in Revda, Sverdlovsk oblast. The fields formed by trees growing in the background area have a regular spatial structure: the concentrations of elements decrease with increase in the distance from the tree trunk to the edge of canopy gap, with the position of sampling point relative to the trunk accounting for more than half of total variance. In polluted areas, the regular component of the field structure is very weakly expressed, and the main role is played by higher-order heterogeneity related to the mosaic pollution pattern on the scale of tens to hundreds of meters.     

Novel approach for assessing heavy metal pollution and ecotoxicological status of rivers by means of passive sampling methods

In order to study the pollution of fluvial ecosystems, it is necessary to analyze not only the levels of chemical contaminants in water, but also those accumulated in the sediment matrix, as well as to assess its ecotoxicological status. Eleven Catalan (Spain) river sections (one sampling point per river) located near urban and industrial areas were sampled during winter of 2009. Water pollutants were collected by using passive samplers as Diffusive Gradient in Thin-Films (DGTs) and Semi-Permeable Membrane Devices (SPMDs). Point water samples were also collected. The concentrations of potentially toxic elements (PTE) in water, filtered water, DGTs and sediment samples were analyzed. Aqueous and organic solvent extracts of sediments samples and organic extracts of SPMDs were performed to assess acute toxicity to Vibrio fischeri by Microtox(?), and chronic toxicity to the green alga Pseudokirschneriella subcapitata. Microtox(?) test was also performed with DGT extracts. The results show that metals content of Catalan river waters are below the freshwater screening US EPA benchmarks, excepting some industrial areas (for Hg, Pb, and Zn). In contrast, sediments levels of some rivers were far above freshwater sediment screening US EPA benchmarks (for Zn, As, Cr, Pb, Ni, Hg, and Mn), particularly in the most industrialized areas. A good correlation was found between toxicity values of extracts (from sediments and DGTs) and PTE levels in sediments. The current results support the suitability of using combined point and passive sampling methods for assessing the chemical and ecotoxicological status of aqueous environments.     

Strategies of adaptation to heavy metal pollution in Deschampsia caespitosa and Lychnis flos-cuculi: Analysis based on dose-response relationship

The response to copper pollution was studied in the vegetative progeny of tufted hair grass (Deschampsia caespitosa (L.) Beauv.) and ragged robin (Lychnis flos-cuculi L.) plants growing together in chronically polluted areas around the Middle Ural Copper Smelter or in background areas. The root elongation test was used, with copper sulfate (0.006–0.51 mg Cu/L) being added directly to the nutrient medium. Using multimodel inference, dose-response curves were plotted for each of 85 maternal plants, and their parameters (effective Cu concentrations and curve slope in the linear segment) were evaluated. The pattern of transformation in dose dependence of root increment upon transition from background to impact populations proved to be basically different in the two species. The curves for L. flos-cuculi showed a parallel shift, with their shape remaining generally unchanged. In D. caespitosa, this transition was accompanied by a decrease in sensitivity to Cu, but tolerance to this metal was found to increase only at the highest concentration range. These results provide evidence for different strategies of adaptation to heavy metal pollution, which are discussed by comparing the physiological and ecological properties of the two species.     

Cypress tree (Cupressus semervirens L.) bark as an indicator for heavy metal pollution in the atmosphere of Amman City,Jordan

Bio-monitoring of air quality in Amman City was investigated by analyzing 36 cypress tree (Cupressus semervirens L.) bark samples from three sites of different anthropogenic activities at the end of summer season 2001. Cypress barks were found to be a good bio-indicator for air pollution in arid regions. Variation in Pb, Zn, Mn, Cr, Ni, Cd, and Cu contents between sites was observed due to different types of activities. Traffic emissions were found to be the main source of heavy metal pollution in the atmosphere of Amman. Lead content was found to be the highest in highly traffic density areas. The industrial part of the city was characterized by high Zn, Mn, Cr, Ni, and Co contents. No significance variations were found in pH values of the bark between the sites. This was attributed to buffering effect of carbonate in the atmosphere originated from soil of the area.     

Overview of the Belgian programme for the surveillance of the territory and the implications of the international recommendations or directives on the monitoring programme

The Royal Decree of 20th July has entrusted the Federal Agency for Nuclear Control (FANC) with the task of controlling the territorial radioactivity and the doses received by the population. Within this agenda, a monitoring programme has been developed over many years, in order to follow the main potential exposure pathways of the population. In practice, several potential vectors of contamination are controlled: air (and rain), surface water (including sediments and biota), soils around nuclear installations, food chain, drinking water etc. To carry out such work, the FANC has collaborated with public or private reputable organisations: The Centre of Nuclear Energy Studies of Mol, The National Institute of Radionuclides of Fleurus, and The Louis Pasteur Public Health Institute of Brussels. A synthesis of this monitoring programme will be presented and the most important deductions will be pointed out. For many years, the tendency has been for tighter control of artificial and natural radioactivity in the environment. This has been achieved by increasingly stringent regulations, regarding environmental monitoring efforts, from international organisations (EC, OSPAR, IAEA). In this context, the FANC in Belgium, is involved in a process that will lead to the adaptation of the Belgian monitoring programme. Different aspects of these adaptations and of their consequences will be presented for illustrative purposes.     

The influence of zeolite type A on heavy metal transfer in the activated sludge process

In areas which are highly urbanised, where water re-use is frequently necessary, the importance of “heavy metal” removal during sewage treatment cannot be overestimated. One critical factor controlling the forms of the metals in the sewage is the chemical matrix of the sewage; as a consequence of their chelating capacity detergent builders are important in modifying the sewage matrix. Laboratory simulations of the activated sludge process have been studied to estimate the impact of the detergent builder zeolite type A on the removal of heavy metals from sewage in this treatment process.Experiments have also been undertaken in which the influent concentrations of the builder were doubled, in an endevour to simulate the effect of a “wash day”. It is apparent from the data presented that under conditions of constant loading, zeolite type A did not significantly affect the concentrations of any of the metals studied with the exception of zinc. However, removal of some of the metals was less than in the presence of a condensed phosphate solution. Under conditions of shock loading the improvement in metal removal which has been observed when condensed phosphates were added under conditions o of variable loading was not observed when zeolite type A was added under similar conditions.     

The use of the shanny Lipophrys pholis for pollution monitoring: a new sentinel species for the northwestern European marine ecosystems

The contamination of aquatic ecosystems by organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) is a matter of great concern. Mussels have been extensively used as sentinel species in a large number of monitoring programs. However, the use of bivalves as the sole species has some limitations, because they are not as responsive as fish to Aryl Hydrocarbon Receptor agonists. Hence, for many marine areas, there is the need to validate new sentinel fish species that can be used in the assessment of pollution by organic contaminants. The shanny Lipophrys pholis is an intertidal fish that combines many characteristics required in a sentinel species: is abundant and easy to catch, has a wide geographical distribution and restrict home range. After larvae recruitment to the intertidal rocky shores, they remain in the same area for the rest of the life-cycle, thus reflecting local pollutants exposure. In order to evaluate the species sensitivity to organic contaminants under field conditions, L. pholis were collected at six sites reflecting different degrees of anthropogenic contamination. The induction of two biomarkers extensively validated in the assessment of PAHs contamination ethoxyresorufin-O-deethylase activity (EROD) and Fluorescent Aromatic Compounds (FACs) was evaluated. In parallel, mussels were collected at the same locations and levels of 16 PAHs and selected heavy metals determined. Overall, the specimens collected in the urban areas showed a significant induction of EROD and FACs (up to a six-fold induction) if compared with the reference sites. Additionally, a positive correlation was observed between the biomarkers and PAHs levels in mussel tissues. Even though further validation is currently in progress, the available data indicate that L. pholis is responsive to organic contaminants such as PAHs, suggesting its future integration in monitoring programmes designed to evaluate the presence of these contaminants in European marine ecosystems.     

生态补偿理论研究进展及争论——基于生态与社会关系的思考

生态补偿的概念自提出便受到学界和政府决策者的广泛关注,并迅速成为近20年来生态保护的主要政策手段。虽然基于生态补偿的政策手段被大范围使用,但是生态补偿的相关理论却处于发展与争论的阶段,该理论的适用性及对现实问题的剖析在实践过程中备受质疑。本文梳理了生态补偿理论发展及构建的过程,将其总结为生态系统服务概念的提出、生态系统服务价值评估方法的建立、以及生态系统服务市场机制的构建三个主要阶段。已有研究更多集中在生态补偿的具体实施层面,如补偿标准、补偿方式、效果评估等方面,但是对基础理论探讨不足。本文从生态补偿理论发展及构建的三个过程,综述了目前对生态补偿理论的讨论及争议,认为在处理"社会—生态"关系的核心问题上,尤其在一些长期依赖并利用自然资源的传统地区或者民族地区,目前学术界和政策决策者均对此问题缺乏深入的理解,这也是实践中生态补偿政策未达到理想效果的主要原因之一。最后,本文提出用"社会生态系统服务"一词代替目前所使用的"生态系统服务",这一概念有助于在理论上避免忽视社会系统及社会与生态系统二者之间的关系,减少不当外部政策干预。     

Estimation of the critical effect level for pollution prevention based on oyster embryonic development toxicity test: the search for reliability

In spite of the consideration that toxicity testing is a reduced approach to measure the effects of pollutants on ecosystems, the early-life-stage (ELS) tests have evident ecological relevance because they reflect the possible reproductive impairment of the natural populations. The procedure and validation of Crassostrea rhizophorae embryonic development test have shown that it meets the same precision as other U.S. EPA tests, where EC(50) is generally used as a toxicological endpoint. However, the recognition that EC(50) is not the best endpoint to assess contaminant effects led U.S. EPA to recently suggest EC(25) as an alternative to estimate xenobiotic effects for pollution prevention. To provide reliability to the toxicological test results on C. rhizophorae embryos, the present work aimed to establish the critical effect level for this test organism, based on its reaction to reference toxicants, by using the statistical method proposed by Norberg-King (Inhibition Concentration, version 2.0). Oyster embryos were exposed to graded series of reference toxicants (ZnSO(4) x 7H(2)O; AgNO(3); KCl; CdCl(2)H(2)O; phenol, 4-chlorophenol and dodecyl sodium sulphate). Based on the obtained results, the critical value for C. rhizophorae embryonic development test was estimated as EC(15). The present research enhances the emerging consensus that ELS tests data would be adequate for estimating the chronic safe concentrations of pollutants in the receiving waters. Based on recommended criteria and on the results of the present research, zinc sulphate and 4-chlorophenol have been pointed out, among the inorganic and organic compounds tested, as the best reference toxicants for C. rhizophorae ELS-test.     

Study on the behavior of the heavy metals Cu, Cr, Ni, Zn, Fe, Mn and 137Cs in an estuarine ecosystem using Mytilus galloprovincialis as a bioindicator species: the case of Thermaikos gulf, Greece

Mussels are worldwide recognized as pollution bioindicators and used in Mussel Watch programs, because they accumulate pollutants in their tissues at elevated levels in relation to pollutant biological availability in the marine environment. The present study deals with the use of Mytilus galloprovincialis as a local bioindicator of heavy metal and (137)Cs contamination in an estuarine ecosystem (Thermaikos gulf, Greece in Eastern Mediterranean). M. galloprovincialis samples were collected monthly from two aquaculture farms during the period April to October 2000. Analyses for the heavy metals Cu, Cr, Ni, Zn, Fe, Mn and (137)Cs showed that the concentrations measured were low and similar to those from other non-polluted Mediterranean areas. In terms of the two sampling stations, there were no statistically significant differences between them. On the contrary, the seasonal evolution of either heavy metals or (137)Cs levels presented high variation. The levels were found to increase during the cold period of the year, especially for Cu, Zn, Mn and Cr which are essential for life. Stable metals were positively inter-related and moreover, metals more involved in biochemical activities seem to present more correlations than others with less significant role in the metabolism of the organisms.     

工业土地利用与行业结构调整研究--基于昆山1400多家工业企业有效问卷的调查

以昆山市工业企业用地利用调查数据为依据。分析了现有昆山工业行业产业结构现状,并选取了6个相应的评价指标一在1414份问卷基础上,应用统计分析法,对所调查的工业内部不同17行业企业用地土地利用程度进行定量化评价。根据定量化评价结果并结合昆山市实际情况和有关的行业发展目标提出了产业调整和提高土地集约利用程度的途径与措施。     

长江中游城市群城市土地利用效率空间溢出效应研究

城市群城市土地利用效率是城市群城市土地要素有效配置、合理利用以及城市经营管理水平的综合体现。在使用DEA方法得到2003～2015年长江中游城市群28个城市土地利用效率并且分析其变化趋势以及空间关联性的基础上,构建SDM模型对长江中游城市群的城市土地利用效率空间溢出效应进行分析。研究结果表明：（1）2003～2015年长江中游城市群城市土地利用效率总体呈波动变化趋势。长江中游城市群城市土地利用效率存在空间负相关关系,城市土地利用效率具有空间异质性;（2）通过构建SDM模型分析表明,外商直接投资额以及人均地区生产总值是长江中游城市群城市土地利用效率的主要驱动因素;（3）长江中游城市群城市土地利用效率的空间溢出效应较弱,在一定程度上反映了长江中游城市群城市之间的空间相互作用较弱,经济联系还不够紧密。因此,长江中游城市群需要进一步构建城市合作机制,提高城市土地利用系统的整体性和联动性,推进区域经济协同发展。