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This article describes and tests a systems theory-based policy indicators model. The framework is used to examine propositions about linkages between states' ecological-spatial characteristics and subsequent selected solid waste management (SWM) -related environmental policies. It was hypothesized that state characteristics of: (1) population density (used as a garbage-per-land area index), (2) population convergence within urban areas, and (3) percent population change in the interval 1980–1985, could jointly explain state variation in both the number and the vigor of SWM policy outputs. Greater levels of spatial pressure were proposed to be related directly to more numerous, more convincing policies. Proposals are grounded in the literature of organizational search theory, crisis stimulation, and technological pressure. Results revealed that the sociospatial model in fact could explain a reasonable proportion of policy variation across states. However, not all hypotheses are supported. Population change shows an indirect, rather than the anticipated direct, relationship with policy output levels. In addition, when used in the model as a pollution intensity index, population density failed to contribute significantly to an explanation of differences in state SWM policy levels. The analysis raises questions about changes occurring over time in the nature and direction of linkages between sociospatial measures and policy responses. This study suggests that strengthening policy indicator models may require questioning key assumptions and theoretical bases, conducting longitudinal studies, and factoring in political, economic, and other policy environment forces.  相似文献   
43.
Remediation of streams impacted by non-point source contaminants requires an understanding of both the areas within a watershed that are contributing contamination to streams and the pathways of contaminant migration to streams. From 1998 to 2002, we studied the migration of 90Sr in the Borschi watershed, a small (8.5 km2) catchment three km south of the Chernobyl Nuclear Power Plant, Ukraine. Fuel particles, distributed in a heterogeneous pattern across the watershed, are weathering and releasing 90Sr from the fuel matrix. Depletion of (90)Sr, evaluated in comparison to the immobile fission product europium-154, is occurring in the channel and wetland sediment. Channel sediments are uniformly depleted in 90Sr with depth. In wetland sediments, there is a zone of depletion in the top 10 cm and a zone of accumulation at depths from 10 to 25 cm. Estimates of 90Sr depletion are used to map the effective source area that has contributed (90)Sr loading to the main channel. The effective source area includes channel bottom sediments, a wetland in the central region of the watershed, and periodically flooded soils surrounding the wetland. The total depletion from the effective source area is estimated to be 36 +/- 7 x 10(10) Bq. Based on observations of stream flow rate and water quality in 1999-2001, the annual 90Sr removal rate from the watershed is estimated to be 1.4 +/-0.2 x 10(10) or 1.5% of the inventory per year. When extrapolated over a 15-year period following the Chernobyl accident, the last value is in reasonable agreement with the estimated depletion of the source area based on 90Sr/154Eu ratios. The 90Sr yearly leaching rate considering the whole watershed is 0.2% while the 90Sr leaching rate considering the effective source area is an order of magnitude higher. Most of the 90Sr release in the watershed has originated from an effective source area of 0.62 km2, or 7% of the watershed area.  相似文献   
44.
This study compares the effectiveness of two regional planning agencies in terms of public support for various planning activities. The Adirondack Park Agency and the Temporary State Commission on Tug Hill have fundamentally different approaches to planning. The Adirondack Park Agency has implemented a restrictive regulatory program with little citizen participation by Adirondack residents. The Tug Hill Commission has implemented an advisory and coordinating program with an emphasis on public input. Residents of two towns in each region were surveyed to determine environmental concern and support for regional planning activities. Respondents from both regions favored a planning agency that incorporates citizen input; controls air, water, and toxic waste pollution; and develops recreation areas. They strongly opposed an agency that regulates private land-use. Basic demographic characteristics and levels of environmental concern were similar in all four towns, but receptivity to various planning activities was consistently greater among residents of the Tug Hill Region. Paired comparisons of the four towns demonstrated no differences between towns of the same region and significant differences between towns of different regions. Public support for regional planning is greater in the Tug Hill Region than in the Adirondack Park.  相似文献   
45.
Many small communities are concerned about health effects from environmental pollutants. One such community, Orwell, in Oswego County, New York, was investigated to determine if the level of cancer was significantly high in comparison to the county and the state. A pilot health study was administered among residents living in a defined area. Results of the survey demonstrated that cancer incidence was higher than both Oswego County and New York State, while cancer mortality was higher for men and lower for woman. A closer examination of the data showed that the way in which health surveys are usually analyzed may not be appropriate for small communities. In particular, some parametric statistics, such as chi-square analysis, might show significant differences between populations when standardized incidence and mortality rates are derived from small samples, yet standard deviations calculated from these data are so large as to cast doubt on the analysis. Researchers have discussed this problem theoretically, but empirical studies illustrating the difficulties have not heretofore appeared in the published literature. For health studies in small communities, greater consideration should be given to risk ratios and the implications of standard deviations.  相似文献   
46.
Environmental Science and Pollution Research - Sorption of pharmaceuticals onto sediments is frequently related to organic matter content. Thus, the present work aimed to compare the effect of...  相似文献   
47.
The Intergovernmental Panel on Climate Change quantified a cumulative remaining carbon budget beyond which there is a high likelihood global average temperatures will increase more than 2 °C above preindustrial temperature. While there is global participation in mitigation efforts, there is little global collaboration to cooperatively mitigate emissions. Instead, countries have been acting as individual agents with independent emission reduction objectives. However, such asymmetric unilateral climate policies create the opportunity for carbon leakage resulting from the shift in embodied carbon emissions within trade networks. In this analysis, we use an optimization-based model of the global crude trade as a case study to demonstrate the importance of a cooperative, system-level approach to climate policy in order to most effectively, efficiently, and equitably achieve carbon mitigation objectives. To do this, we first characterize the cost and life cycle greenhouse gas emissions associated with the 2014 crude production and consumption system by aggregating multiple data sources and developing a balanced trade matrix. We then optimize this network to demonstrate the potential for carbon mitigation through more efficient use of crude resources. Finally, we implement a global carbon cap on total annual crude emissions. We find that such a cap would require crude consumption to drop from 4.2 gigatons (Gt) to 1.1 Gt. However, if each country had an individual carbon allocation in addition to the global cap consistent with the nationally determined contribution limits resulting from the 2015 United Nations Climate Change Conference, allowable consumption would further decrease to approximately 770 million metric tonnes. Additionally, the carbon accounting method used to assign responsibility for embodied carbon emissions associated with the traded crude further influences allowable production and consumption for each country. The simplified model presented here highlights how global cooperation and a system-level cooperative approach could guide climate policy efforts to be more cost effective and equitable, while reducing the leakage potential resulting from shifting trade patterns of embodied carbon emissions. Additionally, it demonstrates how the spatial distribution of crude consumption and production patterns change under a global carbon cap given various carbon accounting strategies.  相似文献   
48.
BackgroundSouth African pesticide market sales data, for two years, 1994 and 1999, were audited to identify change in total and per hectare mass sold and acute toxicity indicator (ATI) (kg sold/rat oral LD50) in the grape, pome, stone fruit, potato and wheat sectors.ResultsTotal pesticide sales (62%), amount per hectare (42%) and number of active ingredients (23%) increased in 1999 compared to 1994 with the grape fruit sector, the most significant contributor over the two years. Total (14%) and per hectare ATI (19%) decreased in 1999, but not substantially with the potato sector the most significant contributor.ConclusionsToxic pesticides were still used in 1999 which highlights a need to develop alternative agricultural and non-chemical pest control methods that reduce usage of pesticides.  相似文献   
49.
Arsenic concentrations of 73 soil samples collected in the semi-arid Zimapán Valley range from 4 to 14 700 mg As kg(-1). Soil arsenic concentrations decrease with distance from mines and tailings and slag heaps and exceed 400 mg kg(-1) only within 500 m of these arsenic sources. Soil arsenic concentrations correlate positively with Cu, Pb, and Zn concentrations, suggesting a strong association with ore minerals known to exist in the region. Some As was associated with Fe and Mn oxyhydroxides, this association is less for contaminated than for uncontaminated samples. Very little As was found in the mobile water-soluble or exchangeable fractions. The soils are not arsenic contaminated at depths greater than 100 cm below the surface. Although much of the arsenic in the soils is associated with relatively immobile solid phases, this represents a long-term source of arsenic to the environment.  相似文献   
50.
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