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21.
Since the establishment, following World War II, of the World System, by which the affluent industrialized countries established various international assistance agencies (including the multilateral development banks, UN affiliates, and Bilaterals), these assistance agencies have invested very large sums in helping finance planning and construction of community sewerage and water supply facilities in the developing countries. However, much of this large investment has been ineffective and wasted, primarily because of the lack of understanding by the staff of the assistance agencies that the design criteria for the facilities must be modified to suit the socio-economic status of the developing country. The developing countries are relatively very poor in terms of available finances, hence cannot afford to emulate Western environmental standards and design practices, especially as related to operation and maintenance, hence much simpler approaches must be used. Experiences in several Asian countries are discussed, and a recommendation is made on how to go about resolving this problem.  相似文献   
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Savannas occur across all of northern Australia and are extensively used as rangelands. A recent surge in live cattle exports to Southeast Asia has caused excessive grazing impacts in some areas, especially near watering points. An important ecological and management question is "how resilient are savanna ecosystems to grazing disturbances?" Resilience refers to the ability of an ecosystem to remain in its current state (resist change) and return to this state (recover) if disturbed. Resilience responses can be measured using field data. These responses can then be modelled to predict the likely resistance and recovery of savannas to grazing impacts occurring under different climatic conditions. Two approaches were used to model resilience responses. First, a relatively simple mathematical model based on a sigmoid response function was used. This model proved useful for comparing the relative resilience of different savanna ecosystems, but was limited to ecosystems and conditions for which data were available. Second, a complex process model, SAVANNA, was parameterised to simulate the structure and function of Australian savannas. Simulations were run for 50 years at two levels of grazing to evaluate resistance and then for another 50 years with no grazing to evaluate recovery. These runs predicted that savanna grasslands were more resistant to grazing (changed less) than red-loam woodlands, which recovered relatively slowly from grazing impacts. The SAVANNA model also predicted that these woodlands would recover slightly slower under the climate change scenario projected for northern Australia.  相似文献   
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Climate change and sea level rise (SLR) pose risks to coastal communities around the world, but societal understanding of the distributional and equity implications of SLR impacts and adaptation actions remains limited. Here, we apply a new analytic tool to identify geographic areas in the contiguous United States that may be more likely to experience disproportionate impacts of SLR, and to determine if and where socially vulnerable populations would bear disproportionate costs of adaptation. We use the Social Vulnerability Index (SoVI) to identify socially vulnerable coastal communities, and combine this with output from a SLR coastal property model that evaluates threats of inundation and the economic efficiency of adaptation approaches to respond to those threats. Results show that under the mid-SLR scenario (66.9 cm by 2100), approximately 1,630,000 people are potentially affected by SLR. Of these, 332,000 (~20%) are among the most socially vulnerable. The analysis also finds that areas of higher social vulnerability are much more likely to be abandoned than protected in response to SLR. This finding is particularly true in the Gulf region of the United States, where over 99% of the most socially vulnerable people live in areas unlikely to be protected from inundation, in stark contrast to the least socially vulnerable group, where only 8% live in areas unlikely to be protected. Our results demonstrate the importance of considering the equity and environmental justice implications of SLR in climate change policy analysis and coastal adaptation planning.  相似文献   
25.
The extent to which existing ozone monitoring data can be used to represent concentrations outside the area immediately surrounding a monitoring station is investigated. The results should be of Interest to those who wish to define areas within which standards are likely to have been exceeded. Relationships are established between the observed second-maximum hour-average ozone concentrations and the area within which It is possible to state with reasonable probability that National Ambient Air Quality Standards (NAAQS) have or have not been exceeded. All pairs of SAROAD stations (Storage and Retrieval of Aerometric Data) separated by 500 km or less which had nearly complete annual data sets were considered for the years 1974 through 1977 to determine the probability that the NAAQS would be exceeded at one station of the pair, given station separation and the observed second-maximum hourly ozone concentration at the other station. The resulting relationship was applied to SAROAD data for 1977, and circles were drawn around each SAROAD monitoring site to show the area within which it is 90% probable that the 120 ppb NAAQS was exceeded during 1977.  相似文献   
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If the goal for managing rangelands is to achieve a balance between production and conservation, then monitoring is essential to detect change and apply corrective action. In some range-land areas of northern Australia, monitoring has detected a tilt in the production-conservation balance towards excessive production. How big is this imbalance? Can it shift back? Robust monitoring is needed to answer these questions. The aim is to know what to monitor, and where. For example, to detect changes caused by livestock on rangeland forage production and soil erosion, indicators linking grazing disturbances to landscape function are needed, that is, indicators that signal how well landscapes are capturing, concentrating, and utilizing scarce water, nutrient, and organic resources. Studies in Australia and the USA document that simple vegetation and soil patch attributes can be measured as indicators of the 'state of health' of landscape function. For example, field and remote sensing-based grazing studies in Australia document that landscapes with a high cover of perennial plant patches function effectively to capture runoff water and nutrients in sediments, whereas landscapes with a low cover of these patches do not — they are dysfunctional — as indicated by large patches of bare soil. Aerial videography is proving to be a robust technique for measuring indicators of landscape function such as small patches of vegetation and the extent of bare soil. These indicators typically have a sigmoidal response to grazing impacts. We illustrate that if these indicators are measured on monitoring sites established near the sigmoidal 'point of inflection’ then small changes in these indicators can be detected.  相似文献   
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Changes in social framework conditions, accelerated by globalization or political inventions, have created new societal demands and requirements on companies. The concept of corporate social responsibility (CSR) is often considered a potential tool for meeting societal demands and criticism as a company voluntarily takes responsibility for society. The spotlight of public attention has only recently come to focus on agribusiness-related aspects of CSR. It is therefore the objective of this paper to provide an overview and a critical examination of the current state of research into CSR in agribusiness from different perspectives. Upon that this paper goals to define CSR special cases in agribusiness and derive implications for further research. CSR in agribusiness is a multi-dimensional and complex concept, which is sensitive to ongoing exchange processes between companies and stakeholders. We conclude with the special position of CSR in agribusiness and that future research should focus on adding value to industry-specific CSR aspects in the general CSR framework borrowed from management literature. Explorative fieldwork such as expert interviews with different stakeholders might be suitable for gaining insights into agribusiness-specific aspects of CSR in firms.  相似文献   
29.
Summary In the past, the water supply and sewage services for the urban regions of developing countries have been provided, in the main, only for the more affluent areas of these cities. This paper, dealing especially with those countries with tropical monsoon climates, advocates the construction of more comprehensive systems.Experience drawn from a wide range of projects and a review of the relevant literature provokes the authors to emphasise the need for suitable manuals of appropriate technology for use in these developing countries. These manuals should provide a full set of environmental guidelines for the design of water supply and sewage/sanitation systems for use in these countries.Dr Harvey F. Ludwig is Chairman and Greg Browder is Environmental Engineer for SEATEC International Consulting Engineers, Bangkok, Thailand.  相似文献   
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