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1.
To supplement an epidemiological investigation into respiratory cancer, a synthetic fabric called tak was used to study the deposition of atmospheric metal pollution within the town of Armadale, central Scotland. Pollution maps showed high concentrations of several metals in areas close to the town's steel foundry and in a second area in the north of the town. Through further statistical analyses, those metals were identified which had probably been emitted by the foundry, and temporal variations in metal deposition patterns were examined. The advantages of this method of low technology sampling, which include the low cost and a high density of sampling sites, are described.  相似文献   

2.
The future of the environment in China until the year 2050 has been forecasted through a heuristic approach. A questionnaire survey was given to a group of Japanese experts concerning 47 selected indices, including past data and reference data about other countries. The indices were related to aspects of the economy, population, food, energy, transportation, and the environment. The experts were requested to plot a graph for each index up to 2050 based on their intuition. The lines drawn by 60 experts were compiled along with their comments, and the characteristics of each index were analyzed. Different values for the indices regarding transportation and per capita GDP were forecasted by the experts, while rather similar values were obtained for those referencing population and food consumption. The respective fields of the experts were found to affect their perspectives on the future. Economists tended to show rather optimistic views, expressing a business-as-usual scenario, while engineers predicted limited growth but technological innovation.  相似文献   

3.
Roads and buildings are considered as primary causes of rural landscape changes. In this study, linear regression models were used to analyze the dynamic influences of environmental factors and variables on roads and rural buildings from 1979 to 2005 in Dongzhi Yuan (tableland) of the Loess Plateau, China. The relationship between roads and rural buildings and their effects on Dongzhi Yuan are discussed also. The results showed that three environmental factors (topography, land cover, and development level) explained roads better than rural buildings referring densities and patterns. The environmental variables significantly related to roads have decreased, whereas those related to rural buildings have increased over time. Among these significant variables, percent of farmland mostly determined the densities and patterns of both roads and rural buildings. There was significant correlation between roads and rural buildings in terms of density and pattern. In addition, roads and rural buildings have increased greatly in gully areas of this region. Therefore, more attention should be paid to planning of roads and rural buildings in Dongzhi Yuan.  相似文献   

4.
Despite the numerous benefits of hydropower production, this renewable energy source can have serious negative consequences on the environment. For example, dams act as barriers for the longitudinal migration of organisms and transport of particulate matter. Accelerated siltation processes in the receiving river reduce the vertical connectivity between river and groundwater. Hydropeaks, caused by short-term changes in hydropower operation, result in a negative impact on both habitat and organisms, especially during winter months when natural discharge is low and almost constant. In this study, we report the current deficits present in the River Rhone from two different scientific perspectives – fish ecology and hydrology. Potential rehabilitation solutions in synergy with flood protection measures are discussed. We focus on the effects of hydropeaking in relation to longitudinal and vertical dimensions and discuss local river widening as a potential rehabilitation tool. The fish fauna in the Rhone is characterized by a highly unnatural structure (low diversity, impaired age distribution). A high correlation between fish biomass and monotonous morphology (poor cover availability) was established. Tracer hydrology provided further details about the reduced permeability of the riverbank, revealing a high degree of siltation with K values of about 4.7 × 10?6 m s?1. Improving the hydrologic situation is therefore essential for the successful rehabilitation of the Rhone River. To this end, hydropeaks in the river reaches must be attenuated. This can be realized by a combination of different hard technical and soft operational measures such as retention reservoirs or slower up and down ramping of turbines.  相似文献   

5.
This article, a theoretical perspective based on a literature study, is a critical evaluation of SIA as part of the EIA process in South Africa against the background of international guidelines and best practices. It includes sections on the historical background of the development of SIA in South Africa, the legal status and requirements of SIA in the country, and a critical evaluation of SIA regulation in South Africa. The conclusion reached in the article is that the persistent problems of SIA practice, experienced in other parts of the world, are also evident in South Africa. Apart from institutional, financial and professional constraints, there are also serious problems associated with approach and methods. This conclusion confirms the findings of empirical studies that SIA in South Africa is neglected, that the practice of SIA in South Africa is not yet on a sound footing, and that it does not receive the professional attention it deserves in a country beset by enormous social challenges. To conclude the article recommendations are made to improve the level of SIA practice in South Africa, and the possible significance of this national case study for international practice is indicated.  相似文献   

6.
In present study focus has been given on estimating quality and toxicity of waste with respect to heavy metals and its impact on groundwater quality, using statistical and empirical relationships between different hydrochemical data, so that easy monitoring may be possible which in turn help the sustainable management of landfill site and municipal solid waste. Samples of solid waste, leachate and groundwater were analyzed to evaluate the impact of leachates on groundwater through the comparison of their hydrochemical nature. Results suggest the existence of an empirical relationship between some specific indicator parameters like heavy metals of all three above mentioned sample type. Further, K/Mg ratio also indicates three groundwater samples heavily impacted from leachate contamination. A good number of samples are also showing higher values for and Pb than that of World Health Organization (WHO) drinking water regulation. Predominance of Fe and Zn in both groundwater and solid waste samples may be due to metal plating industries in the area. Factor analysis is used as a tool to explain observed relation between numerous variables in term of simpler relation, which may help to deduce the strength of relation. Positive loading of most of the factors for heavy metal clearly shows landfill impact on ground water quality especially along the hydraulic gradient. Cluster analysis, further substantiates the impact of landfill. Two major groups of samples obtained from cluster analysis suggest that one group comprises samples that are severely under the influence of landfill and contaminated leachates along the groundwater flow direction while other assorted with samples without having such influence.  相似文献   

7.
Air pollution is one of the most pressing environmental problems which affects likewise urban, industrial and rural areas. Environmental planners, regulators and decision makers need reliable, scientifically based tools to find out strategies for controlling air pollution in a cost-effective way, taking into account the whole productive system. In this framework the basic elements of energy-environmental planning have to be extended to include also waste processing technologies amongst the usually considered pollution sources. Bottom-up optimizing models, based on linear programming techniques and customized for specific cases, represent a powerful tool in energy-environmental management. This paper focuses on the integrated modeling of material flows and energy system performed on a local scale case study (Basilicata Region, Southern Italy) using the linear programming model IEA-MARKAL. We have evaluated the feasibility of the model in representing the waste management system to estimate the environmental impact of the waste processing technologies in the context of the whole productive system. A sensitivity analysis has been carried out to emphasize the connections between tariffs, waste disposal technologies assessment and atmospheric emissions. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
A probability-based sample of 48 of the 152 lakes in the Sawtooth Wilderness, Idaho was conducted in summer 1988. Results from this sample were compared to the Environmental Protection Agency's 1985 probability survey of lakes throughout the western United States, which included 17 lakes in the Sawtooth Wilderness. Although methods differed in several respects, including year, season, sampling location within the lakes, holding times, and sample size, general characterization of lake chemistry for the population of lakes in the wilderness based on the two surveys was very similar. The results indicate that general lake characterization in difficult-to-access wilderness areas of the West can be achieved with a modest investment in resources with the use of volunteers. However, accurate measurement of some non-conservative and low-level analytes such as NO 3 ,NH 4 + , total P, and aluminiun in the lakes probably requires more rigorous attention to sampling protocols and holding times. A two-stage sampling strategy employing extensive use of conductivity on a large number of lakes and intensive detailed chemical characterization on a smaller number of lakes offers an alternative design for describing large populations of wilderness lakes. The relatively high concentrations of fluoride and sulfate in many of the study lakes reflect the weathering of minerals not usually identified on geologic maps. These natural sources of acid anions violate the assumptions in commonly employed empirical models of acidification.  相似文献   

9.
10.
Harbours are heavily stressed coastal habitats characterised by high concentration of contaminant and low diversity of benthic community. The west coast of India harbours most of the major harbours compared to the east coast. Very few studies have compared the macrobenthic community between different Indian harbours. The present study was therefore conducted in three important harbour (Ratnagiri, Goa, Karwar) along the central west coast of India. The paper discusses the health status of the three harbours diagnosed using various biotic indices. Sediment samples were collected using van Veen grab (0.11 m(2)) on board CRV Sagar Sukti. A total of 55 macrobenthic taxa were identified and were numerically dominated by polychaete. Biomass was high (0.14-145.7 g m(-2)) and was made largely by echiurans (>80%). Overall, polychaete dominated the macrobenthic diversity. Opportunistic P.pinnata, Notomastus sp. and Mediomastus sp., dominated the macrobenthic community responding to the increased in the harbour. Biotic indices (Polychaete:Amphipod ratio, ABC curve and geometric class abundance) and the dominance of opportunistic species indicate that, the three harbours are under stress from anthropogenic activities.  相似文献   

11.
Recently, Australian interest in farm dams has focused on rates of harvest of surface waters (runoff), and the impact this has on nearby natural systems. Little research has been directed towards the role of these artificial water bodies in sustaining biological reserves within the wider ecosystem. Macroinvertebrate communities in three farm dams in the Central Tablelands of New South Wales were surveyed, and water quality variables were correlated with species richness and abundance. Community responses to habitat factors including sediment depth, stock use, vegetation and debris were also examined. Communities were described at several taxonomic levels in addition to allocation to trophic groups and primary functional feeding groups.Species richness and abundance of communities were found to vary between dams and between habitat types within dams. The extent of these differences was decreased when communities were described by either trophic status or functional feeding mechanisms. Habitats were influenced by water quality and by physical features of the habitat, with the two factors interacting to define equilibrium conditions. Localised conditions resulted in different macroinvertebrate communities. Physicochemical parameters that correlated most closely with communities included light penetration, chlorophyll-a and conductivity. Habitat factors that were most frequently linked with communities were sediment depth and canopy cover, with localised disturbances related to stock use affecting feeding groups rather than specific taxa.One of the major problems associated with increasing modification of landscapes by agriculture or urbanisation is the fragmentation of undisturbed habitats. Creation of joint aquatic and woodland habitats enhances biodiversity corridors. The recognition of the potential for farm dams as reservoirs of biodiversity and development of management practices that optimise this neglected biodiversity reserve may have much wider benefits biologically, aesthetically and productively.  相似文献   

12.
Available water quality indices have some limitations such as incorporating a limited number of water quality variables and providing deterministic outputs. This paper presents a hybrid probabilistic water quality index by utilizing fuzzy inference systems (FIS), Bayesian networks (BNs), and probabilistic neural networks (PNNs). The outputs of two traditional water quality indices, namely the indices proposed by the National Sanitation Foundation and the Canadian Council of Ministers of the Environment, are selected as inputs of the FIS. The FIS is trained based on the opinions of several water quality experts. Then the trained FIS is used in a Monte Carlo analysis to provide the required input-output data for training both the BN and PNN. The trained BN and PNN can be used for probabilistic water quality assessment using water quality monitoring data. The efficiency and applicability of the proposed methodology is evaluated using water quality data obtained from water quality monitoring system of the Jajrood River in Iran.  相似文献   

13.
The complexity of today’s research problems increasingly demands that scientists move beyond the confines of their own discipline. In this special issue, the basics of a transdisciplinary framework are established and problems analyzed in a specific discipline are successfully integrated in this transdisciplinary network. The intent has been to go beyond only statements about the importance of enabling early stage researchers to work across disciplinary boundaries, and to show that important discoveries are being made at the intersection of disciplines. Embedding various research projects in a more global framework can meet the demands of an interdisciplinary or transdisciplinary approach (especially for early stage researchers) and contribute significantly to sustainable research.  相似文献   

14.
In this article we take a closer look at resistance to the practice of Environmental Impact Assessment (EIA) in mining and energy projects in Guatemala. Collectivities resisting mining and hydropower projects in Guatemala are increasingly using the evaluations of EIAs conducted by international independent professionals. Reaching out to international experts is facilitated by local communities' engagements in transnational networks bringing together activists, NGOs, scientists, journalists and others. We argue that resistance movements resort to international professionals to challenge the limits imposed on them by the national legislation and institutional arrangements as well as by the way in which EIAs are performed in the country. Further, the engagements in networks that facilitate access to knowledge contribute to strengthen the legitimacy of communities' claims. Challenges to and complaints about EIAs are ways in which affected communities try to reclaim their right to participate in decision-making related to their local environment and the development of their communities. Both complaints about EIAs and the use of transnational networks to attain better participation in decision making processes at local levels, illustrated in this study for Guatemala, are common responses to the advancement of extractive industries and hydropower development across Latin America. The widespread of initiatives to challenge EIAs involving international experts in the region show that EIAs have become a sort of a transnational battleground.  相似文献   

15.
Two approaches for setting ecological class boundaries, response curves and a simplified mathematical boundary-setting protocol, were tested for coastal, transitional and open waters in the Gulf of Riga, Baltic Sea. The simplified mathematical boundary-setting protocol defines acceptable ecological status based on expert judgment by a uniform relative deviation from reference conditions. In contrast, response curves derive class boundary definitions from observed changes in biological quality elements along environmental pressure gradients for class boundary definitions. Identification of relevant environmental pressures for the construction of response curves was based on a conceptual model of eutrophication in the Gulf of Riga. Response curves were successfully established for summer chlorophyll a and transparency, as well as for macrozoobenthos abundance in the Central Gulf, macrozoobenthos biotic coefficient in the Southern Gulf, and maximum depth of phytobenthos in the Northern Gulf. In the Gulf of Riga response curves almost always permitted a larger deviation from reference conditions than the 50% deviation applied for the simplified mathematical boundary-setting protocol. The case study clearly demonstrated that class boundary definitions should take into account the sensitivity of the target water body. Also, the class boundaries for different ecological quality elements were internally more consistent than those derived by the simplified mathematical boundary-setting protocol.  相似文献   

16.
This article presents a case study of a successful effort to reach agreement on one of the most intractable environmental issues of our time: wolf management. This case is unusual in several ways. In this case, the members of the negotiating team were ordinary citizens rather than leaders of organized groups. This team was given an unusually high level of authority to write the plan as they saw fit; the agency pledged to implement “whatever they came up with.” The agency convened the process, but agency personnel were not members of the team and attended only when they were invited. The team members were able to reach agreement on this tough issue even though polar opposites were at the table—one who felt that wolves are a “spiritual essence” and another who felt that, as he put it, “wolves, coyotes, and cockroaches have a lot in common”. They produced a detailed plan that addressed all the issues in just 5 months. Another unusual aspect of this effort is that the final agreement does not list the team members. They explained that they wanted their plan to “stand alone” and be judged based on what it said, not on who was involved.However, just after their agreement was completed, a new, pro-wolf control government was elected that refused to endorse the plan. While the government gave various reasons for not ratifying the plan, more and more diverse interest groups came out in support for both the plan and the process that created it. Eventually, overwhelming public support forced the government to sign and implement the plan as written. This demonstrates that, while it is important for a team to seek the sanction of decision-makers, it is perhaps even more important for the general public to see the effort and the final agreement as fair. Strong support from a broad spectrum of the public can help win the necessary political support.In addition to discussing the unorthodox aspects of this consensus-building effort, this article also attempts to give the reader a front row seat to this process by using the informants' own words—words rich in detail, brimming with color and spoken straight from the heart. Certainly their experience dispels any notion that such efforts are simply a matter of following a recipe. During the process, members of the negotiating team experienced the entire gamut of emotions—anger, defeat, humor and, finally, a genuine sense of pride. As team member Patty Denison put it, “We showed that a random group of people could work together and do something truly monumental.”  相似文献   

17.
Biodiversity monitoring surveys are rarely optimised statistically before being initiated. Here, we optimised the monitoring of plants in a temperate forest. The total inventory cost, the number and size of quadrats were optimised to detect a 10% change in species richness over 5 years with α = β = 0.05, using data from ongoing long-term floristic monitoring programs. The procedure showed that the inventory cost would be ca 15% lower using 100-, 200-m2 quadrats instead of 300- or 400-m2 quadrats. Despite the cost associated with the optimisation (e.g. gathering preliminary data) and the imprecise estimates (due to the typically small sample size of the pilot studies), optimisation would often be a better option than expert opinion when designing a monitoring survey.  相似文献   

18.
The inorganic nitrogen transformations occurring at a municipal waste leachate treatment facility were investigated. The treatment facility consisted of a collection well and an artificial wetland between two aeration ponds. The first aeration pond showed a decrease in ammonium (from 3480 (± 120) to 630(± 90) mg ⋅ L−1), a reduction in inorganic nitrogen load (3480 to 1680 mg N ⋅ L−1), and an accumulation of nitrite (< 1.3 mg-N ⋅ L−1 in the collection well, to 1030 mg-N ⋅ L−1). Incomplete ammonium oxidation was presumably the result of the low concentration of carbonate alkalinity (∼2 mg ⋅ L−1), which may cause a limitation in the ammonium oxidation rate of nitrifiers. Low carbonate alkalinity levels may have been the result of stripping of CO2 from the first aeration pond at the high aeration rates and low pH. Various chemodenitrification mechanisms are discussed as the reason for the reduction in the inorganic nitrogen load, including; the reduction of nitrite by iron (II) (producing various forms of gaseous nitrogen); and reactions involving nitrous acid. It is suggested that the accumulation of nitrite may be the result of inhibition of nitrite oxidizers by nitrous acid and low temperatures. Relative to the first aeration pond, the speciation and concentration of inorganic nitrogen was stable in the wetlands and 2nd aeration pond. The limited denitrification in the wetlands most probably occurred due to low concentrations of organic carbon, and short retention times.  相似文献   

19.
This paper describes the use of statistical regression models to characterize temporal trends in groundwater monitoring data collected between 1980 and 1990 on 15 wells and 13 parameters (195 cases in all) at the KL Avenue landfill site in Kalamazoo County, Michigan. This site was used as a municipal landfill prior to 1980, then was placed on the Superfund site list in 1982 after ground-water contamination was found.Six temporal regression trend models were defined using linear and quadratic regression models. These trends were used to classify each of the 195 cases as: improving, deteriorating, or stable over the 1980–1990 time period. Using these classifications it was determined that there were more than twice as many improving cases as deteriorating conditions at the KL site during this time period. These models provide a method for visualizing and interpreting trends in ground-water quality at individual well locations within the contaminant plume and for assessing the chemical trend behavior of the overall plume. The improving, deteriorating, and stable trend categories were developed for two purposes. The first purpose is to facilitate comprehension of information contained in large amounts of water quality data. The second is to assist communication among the many different groups of people who recommend actions, including remediation responsibilities at Superfund sites, like the KL site.A normal probability model was used in the trend classifications. This model contained provisions to accommodate nondetect data and other abnormal laboratory determinations which can influence the trend selection process. The robustness of this classification procedure was examined using a lognormal probability model. The overall conclusions about the KL site using the lognormal model were similar to those obtained using the normal model. However, some individual trend indications were different using the lognormal model. The Shapiro-Wilk test was used to check the adequacy of both the normal and lognormal models. The lognormal model was found to be a somewhat more adequate model for fitting the KL site data, but was not found to be superior to the normal model for each case.The normal and lognormal models were both found to be suitable for determining overall trend conditions at this site. Both models are recommended for these purposes assuming an understanding of the statistical constraints and hydrochemical context. However, it is recommended that the search for more adequate trend models continues.  相似文献   

20.
Problems associated with urban wastes are now at crisis stage in Nigeria. All efforts made to solve the problems have failed, as the efforts were directed towards instant cleaning rather than long lasting programs to cope with problems associated with environmental sanitation. Measurements were taken of the domestic waste generated by randomly selected households in Ilorin, to predict the generation rate for the city. The data was subjected to various analyses. The models used in developed nations were found inappropriate to predict the waste generation rate of the people at Ilorin because of cultural factors. Various methods to cope with the environmental sanitation problems of cities of developing areas were then suggested.  相似文献   

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