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1.
Optimum natural resource management and biodiversity conservation are desirable goals. These, however, often exclude each other, since maximum economic benefits have promoted drastic reductions in biodiversity throughout the world. This dilemma confronts local stakeholders, who usually go for maximizing economic inputs, whereas other social (e.g., academic) sectors are favor conservation practices. In this paper we describe the way two scientific approaches—landscape and participatory research—were used to develop sound and durable land use scenarios. These two approaches included expert knowledge of both social and environmental conditions in indigenous communities. Our major emphasis was given to detect spatially explicit land use scenarios and capacity building in order to construct a decision support system operated by stakeholders of the Comunidad Indigena de Nuevo San Juan Parangaricutiro in Mexico. The system for decision-making was fed with data from inventories of both abiotic and biotic biodiversity components. All research, implementation, and monitoring activities were conducted in close collaboration with members of the indigenous community. As a major result we obtained a number of forest alternative uses that favor emerging markets and make this indigenous community less dependent on a single market. Furthermore, skilled members of the community are now running the automated system for decision-making. In conclusion, our results were better expressed as products with direct benefits in local livelihoods rather than pure academic outputs.  相似文献   

2.
A multivariate statistical technique, cluster analysis, was used to assess the logged surface water quality at an irrigation project at Al-Fadhley, Eastern Province, Saudi Arabia. The principal idea behind using the technique was to utilize all available hydrochemical variables in the quality assessment including trace elements and other ions which are not considered in conventional techniques for water quality assessments like Stiff and Piper diagrams. Furthermore, the area belongs to an irrigation project where water contamination associated with the use of fertilizers, insecticides and pesticides is expected. This quality assessment study was carried out on a total of 34 surface/logged water samples. To gain a greater insight in terms of the seasonal variation of water quality, 17 samples were collected from both summer and winter seasons. The collected samples were analyzed for a total of 23 water quality parameters including pH, TDS, conductivity, alkalinity, sulfate, chloride, bicarbonate, nitrate, phosphate, bromide, fluoride, calcium, magnesium, sodium, potassium, arsenic, boron, copper, cobalt, iron, lithium, manganese, molybdenum, nickel, selenium, mercury and zinc. Cluster analysis in both Q and R modes was used. Q-mode analysis resulted in three distinct water types for both the summer and winter seasons. Q-mode analysis also showed the spatial as well as temporal variation in water quality. R-mode cluster analysis led to the conclusion that there are two major sources of contamination for the surface/shallow groundwater in the area: fertilizers, micronutrients, pesticides, and insecticides used in agricultural activities, and non-point natural sources.  相似文献   

3.
This paper describes an online water quality monitoring and management system that was developed by combining a chemical oxygen demand sensor with an artificial neural network technology and a virtual instrument technique. The system was used to model the hydrological environment of the Liming River basin in Daqing City, China, in an effort to maintain the water quality in this basin at a level compatible with the status of Daqing City as a scenic resort. Operation of the system during the past 2 years has shown that an optimal allocation of water (including water released from an environmental reservoir to mitigate pollution events) could be achieved for the basin using the information gathered by the system; using mathematic models established for this system, the quantity of water released from the reservoir is adequate to improve the overall water environment. The results demonstrate that the system provides an effective approach to water quality control for environmental protection.  相似文献   

4.
Runoff from crop production in agricultural watersheds can cause widespread soil loss and degradation of surface water quality. Beneficial management practices (BMPs) for soil conservation are often implemented as remedial measures because BMPs can reduce soil erosion and improve water quality. However, the efficacy of BMPs may be unknown because it can be affected by many factors, such as farming practices, land-use, soil type, topography, and climatic conditions. As such, it is difficult to estimate the impacts of BMPs on water quality through field experiments alone. In this research, the Soil and Water Assessment Tool was used to estimate achievable performance targets of water quality indicators (sediment and soluble P loadings) after implementation of combinations of selected BMPs in the Black Brook Watershed in northwestern New Brunswick, Canada. Four commonly used BMPs (flow diversion terraces [FDTs], fertilizer reductions, tillage methods, and crop rotations), were considered individually and in different combinations. At the watershed level, the best achievable sediment loading was 1.9 t ha(-1) yr(-1) (89% reduction compared with default scenario), with a BMP combination of crop rotation, FDT, and no-till. The best achievable soluble P loading was 0.5 kg ha(-1) yr(-1) (62% reduction), with a BMP combination of crop rotation and FDT and fertilizer reduction. Targets estimated through nonpoint source water quality modeling can be used to evaluate BMP implementation initiatives and provide milestones for the rehabilitation of streams and rivers in agricultural regions.  相似文献   

5.
Increasing salinity is one of the most significant and widespread forms of groundwater pollution in coastal areas. This paper presents the causes and impacts of saline water intrusion in coastal areas. Various causes of salt water intrusion, and approaches for the determination of its extent and various measures to control the salt water intrusion are described. An aquifer performance test (APT) approach is presented to identify the extent of existing salt water intrusion in the study area located in the southwest coastal region of Gujarat State (India). A resistivity based experimental technique is used to identify the quality of the groundwater available at different depths. A methodology is presented to assess the extent of available fresh and saline groundwater and to find out the limit up to which lower saline groundwater can be withdrawn for industrial purposes without affecting the upper fresh water layer which can be made available for domestic purposes.  相似文献   

6.
Energy Systems Theory (EST) provides a framework for understanding and interpreting sustainability. EST implies that "what is sustainable" for a system at any given level of organization is determined by the cycles of change originating in the next larger system and within the system of concern. The pulsing paradigm explains the ubiquitous cycles of change that apparently govern ecosystems, rather than succession to a steady state that is then sustainable. Therefore, to make robust decisions among environmental policies and alternatives, decision-makers need to know where their system resides in the cycles of change that govern it. This theory was examined by performing an emergy evaluation of the sustainability of a regional system, the San Luis Basin (SLB), CO. By 1980, the SLB contained a climax stage agricultural system with well-developed crop and livestock production along with food and animal waste processing. The SLB is also a hinterland in that it exports raw materials and primary products (exploitation stage) to more developed areas. Emergy indices calculated for the SLB from 1995 to 2005 revealed changes in the relative sustainability of the system over this time. The sustainability of the region as indicated by the renewable emergy used as a percent of total use declined 4%, whereas, the renewable carrying capacity declined 6% over this time. The Emergy Sustainability Index (ESI) showed the largest decline (27%) in the sustainability of the region. The total emergy used by the SLB, a measure of system well-being, was fairly stable (CV?=?0.05). In 1997, using renewable emergy alone, the SLB could support 50.7% of its population at the current standard of living, while under similar conditions the U.S. could support only 4.8% of its population. In contrast to other indices of sustainability, a new index, the Emergy Sustainable Use Index (ESUI), which considers the benefits gained by the larger system compared to the potential for local environmental damage, increased 34% over the period.  相似文献   

7.
The present study investigates the physical, chemical, and biological characteristics of spring water samples in Shoubak area in the southern Jordan. The samples were collected from May 2004 to May 2005. All samples were analyzed for temperature, conductivity, dissolved oxygen, pH, major cations (Ca2+, Mg2+, K+, Na+), major anions (Cl, NO3, HCO3, SO42−, PO43−, F), and trace metals (Fe2+, Al3+, Mn2+, Cu2+, Cr3+, Ni2+, Zn2+, Pb2+, Cd2+). Water quality for available springs showed high salinity through long period of contact with rocks. The ion concentrations in the water samples were from dissolution of carbonate rocks and ion exchange processes in clay. The general chemistry of water samples was typically of alkaline earth waters with prevailing bicarbonate chloride. Some springs showed elevated nitrate and sulfate contents which could reflect to percolation from septic tanks, cesspools, and agricultural practices. The infiltration of wastewater from cesspools and septic tanks into groundwater is considered the major source of water pollution. The results showed that there were great variations among the analyzed samples with respect to their physical, chemical and biological parameters, which lie below the maximum permissible levels of the Jordanian and WHO drinking water standards. The results indicate that the trace metals of spring’s water of Shoubak area do not generally pose any health or environmental problems. Factor analysis was used to identify the contributers to water quality. The first factor represents major contribution from anthropogenic activities, while the second one represents major contribution from natural processes.  相似文献   

8.
The study investigated the response of surface water quality to urbanization in Xi'an, China. We qualitatively described the change in urban land use from 1996 to 2003, analyzed the status of the surface water environment, and constructed a model of urban expansion to simulate the water environment's response to urbanization. Our results revealed that patterns of land use changed dramatically, the rate of economic growth exceeded that of urbanization during the study period, and increasing urban land use was correlated with fluctuations in water quality. The simulated results suggested that urbanization had reached the environmental carrying capacity based on the average land utility and the marginal costs of pollution.  相似文献   

9.
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.  相似文献   

10.
The relationship between stream water quality and landscape activities is difficult to evaluate where the principal source of stream flow is ground water seepage because the average travel time from ground water recharge areas to stream discharge positions can be on the order of decades. We tested the idea that past and future baseflow water quality can be predicted based on a synoptic survey of ground water recharge age-dates (based on chlorofluorocarbon [CFC] measurements) and water quality measurements obtained at the ground water-surface water interface. In this study we (i) characterize the discharge-weighted age distribution and water quality of ground water seepage into the Little Plover River (LPR); (ii) use this information to backcast and forecast baseflow NO(3)(-) concentrations; and (iii) evaluate NO(3)(-) backcasts against historical baseflow data (1960 to 2000). The discharge-weighted apparent CFC age of ground water seepage into the LPR was 23.7 (+/-7) yr. Baseflow backcasts matched the four decade rise of baseflow NO(3)(-) from 2 to 8 mg L(-1). Baseflow forecasts included three scenarios. Scenario A projects the historical rise of NO(3)(-) in the LPR basin's ground water recharge through 2050. Scenario B projects a leveling off of NO(3)(-) in ground water recharge in the year 2000. Scenario C projects a leveling off in the year 1985. Under Scenario A, LPR baseflow NO(3)(-) will increase steadily from 8 to 19 mg L(-1) between 2000 and 2050. Under scenarios B and C baseflow NO(3)(-) will plateau at 13 mg L(-1) in 2030 and at 10 mg L(-1) in 2010, respectively. The approach developed in this study can be used to (i) reconstruct historical baseflow water quality patterns in the absence of long-term monitoring data and (ii) project the effects of potential management decision on future water quality.  相似文献   

11.
Environmental impacts of the construction-phase drainage congestion along the Dhaka City Flood Control Embankment were assessed by a pilot questionnaire survey (in 1991) among the target population adjacent to the embankment. The results of the survey indicated that, despite significant alleviation of river flooding, the majority of the respondents experienced a new type of flood problem in the form of stagnant water inside the embankment, immediately following its construction. Not only had this stagnant water flooded and damaged their property, it had exposed them to a number of other environmental problems, such as accumulation of municipal sewage, foul odors, mosquitoes, and growth of water hyacinth. The study found that the respondents' assessments of these environmental problems differed significantly according to the magnitude of the impact of stagnant water upon two subgroups within the target population. A postsurvey follow-up in 1994 indicated that this problem of drainage congestion had largely been alleviated by completing the construction of a number of drainage regulators. The study concludes by stressing the importance of synchronizing the construction of drainage structures with that of the embankment systems and by underlining policy implications for flood-vulnerable land use adjacent to embankments.  相似文献   

12.
13.
Two years of experience with EIA in Flanders (northern Belgium) was evaluated in order to gain perspective on the effectiveness of the administrative procedure. The four essential characteristics of the EIA procedure that were evaluated are: completeness, open and public character, objectivity, and verifiability. Representatives of all parties involved in the EIA procedure were interviewed. The result of the evaluation is a list of major problems with EIA. Recommendations for a more efficient procedure are suggested at a time when a proposal for a new, comprehensive, and permanent EIA decree is being discussed. The evaluation of the administrative procedure for EIA in Flanders shows that several vital characteristics of the EIA procedure are lacking. This reduces the obligatory and open nature of the process, resulting in insufficient guarantees that the environment receives the altention it deserves during the decision-making process.  相似文献   

14.
15.
Residents' perceptions of water quality change following remediation work in the upper Pymme's Brook catchment (north London) were elicited by questionnaire and compared with monitored changes in Escherichia coli count and BMWP (The Biological Monitoring Working Party (BMWP)) score. The wider usefulness of consumer perception surveys was then discussed. Monthly data collected between 1990 and 1996 shows that both E. coli count and BMWP score improved following flushing of the foul sewerage system in 1992, but that only E. coli count improved following the subsequent completion of large-scale remedial engineering works. Local residents were surveyed regarding their awareness of the scheme, and the causes of pollution, together with their perceptions as to the effects of the engineering works and of the resulting water quality improvements. Most respondents selected and ranked indicators in a way that suggested they had an awareness of the significance of various indicators of pollution severity. Following completion of the remediation scheme, residents perceived the watercourse to contain less rubbish and sewage fungus, and to have an improved colour and smell, which corresponds favourably to the monitored improvements. However, respondents' perceptions were found to vary when the study population was sub-divided using a range of parameters. For instance, frequent observers of the brook were most likely to correctly identify sewage as the main form of pollution. These divergent perceptions suggest that there may be considerable difficulties when perception surveys are used to quantify 'benefits' following environmental improvement programmes. Nevertheless, the survey was clearly beneficial in enhancing residents' awareness of their environment and the role of their voice in its management.  相似文献   

16.
Soil variability in watersheds accounts for the problem of partitioning downstream water quality data and evaluating sources of non-point pollution. This review of previous water quality studies was conducted to examine more closely the influence of soil properties on pollutant export. The approach used in this paper was to start with data from the two largest watersheds (Maumee and Sandusky) and then compare them on a unit area export basis with data from intermediate-size and smaller watersheds. General relationships between pollutant levels at the river mouth and upstream soil conditions are vague and seemingly contradictory at the large-watershed scale. With smaller watersheds, it can be determined that soil texture, slope, and internal drainage are controlling factors for pollutant export. Although Paulding (very-fine, illitic, nonacid, mesic Typic Epiaquept) and Roselms (very-fine, illitic, mesic Aeric Epiaqualf) soils occupy only 5% of the Maumee basin, they generate more than 10 times as much sediment per unit area as the tile-drained Hoytville (fine, illitic, mesic Mollic Epiaqualf) soils that occupy 16% of the Maumee basin. Tile drainage of very poorly drained soils that are formed from either glacial till or silty to sandy lake deposits reduces runoff and increases downward movement of soluble nutrients into tile drains. The assumption that sloping moraine areas are the primary source of pollutants should be reexamined based on this review.  相似文献   

17.
The Urban Cleaning Company of the City of Rio de Janeiro - COMLURB launched the Recycling Separation Center Project (Projeto Central de Separação de Recicláveis or CSR) in 2003. The objectives of the project were the adequate disposal of solid urban waste as well as the generation of employment and income. The COMLURB Project had economic, environmental and social facets, and the researchers sought to establish whether COMLURB had prepared reports that would enable evaluation of the investment made and the results obtained. In particular, the researchers sought to establish whether COMLURB financial statements set out the results of actions inherent to the CSR. We concluded from our analysis of the Project that the three elements of sustainability (social, environmental and economic), despite being fully present, were not adequately demonstrated. This study therefore proposes a model report with a view to enabling various information users to evaluate the results of the CSR Project.  相似文献   

18.
An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.  相似文献   

19.
Summary This paper measures the diversity of environmental impacts inherent within a proposal by the Central Electricity Generating Board (CEGB) to build a demonstration wind farm at Langdon Common in the North Pennines, UK. This assessment was made in April, 1989 in the wake of the European Community Directive on Environmental Impact Assessment (EIA) and its subsequent interpretation within the UK Town and Country Planning (Assessment of Environmental Effects) Regulations (1988).Langdon Common lies within an Area of Outstanding Natural Beauty (AONB) and within a Site of Special Scientific Interest (SSSI). These designations create a contentious choice of site made by the CEGB and the extent of environmental impact is subsequently made more broad. While the conclusions drawn are specific to Langdon Common, the methodology evolved within the project lends itself to further application to other sites in the future. The following Environmental Impact Assessment can, therefore, be seen as a step towards the reconciliation of the acceptable siting of wind turbines in the UK and the capacity of the planning system to regulate such development.This paper by Alex Steele received the Institution of Environmental Sciences award and First Prize for the best undergraduate environmental project in the UK in 1989. Alex Steele graduated from Sunderland Polytechnic in that year and now works as an Environmental Planner for a leading company of Environmental Management Consultants.  相似文献   

20.
In this paper we quantify the additional water quality benefits that can be achieved through coordinated cumulative impact management. To do this we simulate coordinated and un-coordinated revegetation investments and compare their impact on achieving regional water quality goals. Our results show that coordination between multiple mining companies achieves additional benefits since prioritization is enabled across a broader range of investment opportunities. Additionally, when coordinated investment is permitted beyond the boundaries of coal mining leases, results show that additional benefits are greatly enhanced since these regions provide more rewarding investment opportunities. Results illustrate (a) how regional coordination may influence reputational benefits of investments, and (b) that coordination is beneficial when investment opportunities are unevenly distributed across the landscape. When additional benefits are achievable, we suggest that mining companies should develop collective investment projects with an understanding of how coordination influences project costs. Similarly, investment projects should be developed with an understanding of investment tradeoffs and how these may adversely impact on regional stakeholders and hence industry reputation. The mining industry has significant potential to contribute to regional wellbeing; however, land management policies must be flexible and promote incentives to enable companies to invest beyond compliance.  相似文献   

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