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61.
An assessment of the heavy metal content and biological pollution burden of an abattoir dumpsite, an automobile carwash, the Ikpoba River, and a private water borehole located near the abattoir dumpsite was conducted in Benin City in Southern Nigeria, during the rainy and dry seasons. The water samples’ pH was lower than the permissible values, with the river water displaying color and possessing a slight odor. Iron concentrations exceeded the permissible limits for drinking water at all four of the sampling stations in the study area, although not in samples collected from the control station, station 5, a public water borehole that is located some distance away. Lead values were higher than drinking water standards in the samples collected from stations 1 through 4, with some exceptions during the rainy season. Copper, nickel, arsenic, chromium, and aluminum were detected in three out of the four sampling stations located within the study area. However, these metals were detected at levels that were within regulatory limits. The detection of three metals (iron, lead, and zinc) within the study area at levels exceeding drinking water limits suggested that a complete cycle of movement of pollutants into the sampling stations had occurred. Significant biological presences were also detected, as the Ikpoba River water had a standard plate count (SPC) of 130 most probable number (MPN) and a 22 MPN presumptive coliform count (PCC) or 22 MPN. However, Escherichia coli (E. coli) confirmatory tests recorded less than 2 MPN in both seasons. The study has shown that the quality of water in the river may be compromised by effluent discharges from the dumpsite and the carwash channel. Therefore, this situation requires more stringent enforcement of local environmental laws and maintenance of safe distances between domestic and industrial waste sources and domestic or private water wells.  相似文献   
62.
Generally, one expects evapotranspiration (ET) maps derived from optical/thermal Landsat and MODIS satellite imagery to improve decision support tools and lead to superior decisions regarding water resources management. However, there is lack of supportive evidence to accept or reject this expectation. We “benchmark” three existing hydrologic decision support tools with the following benchmarks: annual ET for the ET Toolbox developed by the United States Bureau of Reclamation, predicted rainfall‐runoff hydrographs for the Gridded Surface/Subsurface Hydrologic Analysis model developed by the U.S. Army Corps of Engineers, and the average annual groundwater recharge for the Distributed Parameter Watershed Model used by Daniel B. Stephens & Associates. The conclusion of this benchmark study is that the use of NASA/USGS optical/thermal satellite imagery can considerably improve hydrologic decision support tools compared to their traditional implementations. The benefits of improved decision making, resulting from more accurate results of hydrologic support systems using optical/thermal satellite imagery, should substantially exceed the costs for acquiring such imagery and implementing the remote sensing algorithms. In fact, the value of reduced error in estimating average annual groundwater recharge in the San Gabriel Mountains, California alone, in terms of value of water, may be as large as $1 billion, more than sufficient to pay for one new Landsat satellite.  相似文献   
63.
This work highlights the evolution of flood disasters and their impacts upon environmental and socioeconomic aspects both worldwide and in Small Island Developing States (SIDS) in particular. For our research, we reviewed the stress factors affecting flood disasters and performed surveys of two focus groups in Funchal municipality on Madeira Island (Portugal). Our research identifies the main causes of the serious impacts that flash floods can have on Funchal city. These include:
  • The occupation of floodplain areas,
  • Canalization of water courses,
  • Erosion and transport of soil from upstream hillslopes due to deforestation, and
  • Intensive precipitation of long duration.
  相似文献   
64.
In the Wasatch Range Metropolitan Area of Northern Utah, water management decision makers confront multiple forms of uncertainty and risk. Adapting to these uncertainties and risks is critical for maintaining the long‐term sustainability of the region's water supply. This study draws on interview data to assess the major challenges climatic and social changes pose to Utah's water future, as well as potential solutions. The study identifies the water management adaptation decision‐making space shaped by the interacting institutional, social, economic, political, and biophysical processes that enable and constrain sustainable water management. The study finds water managers and other water actors see challenges related to reallocating water, including equitable water transfers and stakeholder cooperation, addressing population growth, and locating additional water supplies, as more problematic than the challenges posed by climate change. Furthermore, there is significant disagreement between water actors over how to best adapt to both climatic and social changes. This study concludes with a discussion of the path dependencies that present challenges to adaptive water management decision making, as well as opportunities for the pursuit of a new water management paradigm based on soft‐path solutions. Such knowledge is useful for understanding the institutional and social adaptations needed for water management to successfully address future uncertainties and risks.  相似文献   
65.
There is a growing demand for alternatives to Sweden’s current dominant silvicultural system, driven by a desire to raise biomass production, meet environmental goals and mitigate climate change. However, moving towards diversified forest management that deviates from well established silvicultural practices carries many uncertainties and risks. Adaptive management is often suggested as an effective means of managing in the context of such complexities. Yet there has been scepticism over its appropriateness in cases characterised by large spatial extents, extended temporal scales and complex land ownership—characteristics typical of Swedish forestry. Drawing on published research, including a new paradigm for adaptive management, we indicate how common pitfalls can be avoided during implementation. We indicate the investment, infrastructure, and considerations necessary to benefit from adaptive management. In doing so, we show how this approach could offer a pragmatic operational model for managing the uncertainties, risks and obstacles associated with new silvicultural systems and the challenges facing Swedish forestry.  相似文献   
66.
Islamic banking has established for the last 40 years, yet only recently researchers acknowledge social failures of Islamic banking and finance. This has led to a proposition of forming new forms of banking and non-banking institutions that include social banking. It is argued that in considering the developmentalist needs of the Muslim societies in Malaysia, there is a need to go back to fundamentals of Islamic finance in realising the aspirational Islamic moral economy that emphasises on the social good, capacity development at the individual and social levels. This paper aims to explore the concept of social banking and search for the possibilities for internalisation in Malaysian Islamic banking. To gain understanding on this pertinent issue, an empirical investigation was conducted at 17 Islamic banks in Malaysia. A mixed method was employed. For the primary data collection, 477 respondents of Islamic banks clients and employees participated in a self-administrated survey, and 11 respondents from the executive and managerial level of eight Islamic banks involved in a semi-structured interview survey. The integrated analysis implies that Islamic banking significantly contributes to socio-economic development. On the contrary, financial and economic practices in everyday life do not reflect the social economic justice. The result further illustrates that the Islamic banks lack social contributions as they prone to practice efficiency-oriented institutions. Hence, a social banking model is needed to solve the lack of socio-economic development issue in the current practice of Islamic bank.  相似文献   
67.
Young, Charles A., Marisa I. Escobar‐Arias, Martha Fernandes, Brian Joyce, Michael Kiparsky, Jeffrey F. Mount, Vishal K. Mehta, David Purkey, Joshua H. Viers, and David Yates, 2009. Modeling the Hydrology of Climate Change in California’s Sierra Nevada for Subwatershed Scale Adaptation. Journal of the American Water Resources Association (JAWRA) 45(6):1409‐1423. Abstract: The rainfall‐runoff model presented in this study represents the hydrology of 15 major watersheds of the Sierra Nevada in California as the backbone of a planning tool for water resources analysis including climate change studies. Our model implementation documents potential changes in hydrologic metrics such as snowpack and the initiation of snowmelt at a finer resolution than previous studies, in accordance with the needs of watershed‐level planning decisions. Calibration was performed with a sequence of steps focusing sequentially on parameters of land cover, snow accumulation and melt, and water capacity and hydraulic conductivity of soil horizons. An assessment of the calibrated streamflows using goodness of fit statistics indicate that the model robustly represents major features of weekly average flows of the historical 1980‐2001 time series. Runs of the model for climate warming scenarios with fixed increases of 2°C, 4°C, and 6°C for the spatial domain were used to analyze changes in snow accumulation and runoff timing. The results indicated a reduction in snowmelt volume that was largest in the 1,750‐2,750 m elevation range. In addition, the runoff center of mass shifted to earlier dates and this shift was non‐uniformly distributed throughout the Sierra Nevada. Because the hydrologic model presented here is nested within a water resources planning system, future research can focus on the management and adaptation of the water resources system in the context of climate change.  相似文献   
68.
Stormwater runoff from the University of California, Davis/U.S. Department of Energy Laboratory for Energy‐Related Health Research (UCD/US DOE LEHR) Superfund site located on the University of California campus in Davis, California, has been found to contain over 500 ng/L of total recoverable mercury, which is about ten times the California Toxics Rule criterion. This stormwater runoff is discharged to Putah Creek, which is Clean Water Act Section 303(d) listed as impaired for excessive mercury bioaccumulation in edible fish. A discussion is presented on the potential impact of the mercury in stormwater runoff from LEHR leading to excessive bioaccumulation of mercury in Putah Creek fish. The mercury in the stormwater runoff is derived from former flooding of the soils near the creek, which contains mercury derived from abandoned upstream mercury mines located in the Coast Range Vaca Hills to the west of LEHR. The implications of this situation for implementing a Total Maximum Daily Load (TMDL) to control mercury in stormwater runoff to Putah Creek are presented. © 2009 Wiley Periodicals, Inc.  相似文献   
69.
70.
Real-time particle sizers provide rapid information about atmospheric particles, particularly peak exposures, which may be important in the development of adverse health outcomes. However, these instruments are subject to erroneous readings in high-humidity environments when compared with measurements from filter-based, federal reference method (FRM) samplers. Laboratory tests were conducted to evaluate the ability of three inlet conditioners to dry aerosol prior to entering a real-time particle sizer for measuring coarse aerosols (Model 3321 Aerodynamic Particle Sizer, APS) under simulated highly humid conditions. Two 30 day field studies in Birmingham, AL, USA were conducted to compare the response of two APSs operated with and without an inlet conditioner to that measured with FRM samplers. In field studies, the correlation of PM(10-2.5) derived from the APS and that measured with the FRM was substantially stronger with an inlet conditioner applied (r2 ranged from 0.91 to 0.99) than with no conditioner (r2 = 0.61). Laboratory experiments confirmed the ability of the heater and desiccant conditioner to remove particle-borne moisture. In field tests, water was found associated with particles across the sizing range of the APS (0.5 microm to 20 microm) when relative humidity was high in Birmingham. Certain types of inlet conditioners may substantially improve the correlation between particulate mass concentration derived from real-time particle sizers and filter-based samplers in humid conditions.  相似文献   
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