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61.
ABSTRACT: The psychosocial impact of a large water impoundment project upon members of a small farming community located within central Ohio was evaluated using a study-restudy research design. Attitudes toward selected community variables were examined during the initial stages of land acquisition and reevaluated four years later at the completion of the project. The findings revealed that fragmentation of the “social fabric” of the community did not occur. Several statistically significant differences were observed between the two data sets but the findings indicated that community residents held more positive attitudes toward their community following the development action than at the beginning of the project.  相似文献   
62.
ABSTRACT. Construction of water impoundment projects often necessitates relocation of numerous rural residents which can result in social disruption of established interaction patterns within affected groups. A research study was conducted within two communities in West Virginia and two communities in Ohio which had recently been subjected to watershed development. The objective of the research was to evaluate the social-psychological response of local residents to the forced relocation and subsequent disruptive effects of the resettlement. The dependent variable used in the research was community alienation. The findings revealed that the affected community groups were not significantly different in terms of alienation from the non-affected base groups. This finding suggests that forced relocation did not consistently lead to personal alienation from the changed community. It was noted, however, that negative attitudes were identifiable among the affected community members but the negative comments appeared to be directed toward the change agency and toward physical relocation rather than the community per se.  相似文献   
63.
This paper considers how regional greenhouse gas emissioninventories can be determined. It presents a greenhousegas emissions inventory, by source, for the East Midlandsthat has been compiled as part of a regional study intoclimate change impacts in the United Kingdom. This hasused available local data, and national emissions datawith appropriate scaling factors. Total greenhouse gasemissions for the region are estimated to be 59 milliontonnes of carbon dioxide equivalent (CO2 equivalent)for 1997. Of these emissions, approximately 86% werecarbon dioxide emissions, 7% methane emissions, and 5%were nitrous oxide, with emissions of hydrofluorocarbons(HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride(SF6) contributing less than 2% of total emissions.  相似文献   
64.
This paper describes the progress that local authorities in England and Wales are making in adapting to the threat of climate change and taking action to reduce greenhouse gas emissions. The responses from surveys of local authorities in England and Wales carried out in 2000 (IDeA, Reducing Greenhouse Gas Emissions: survey of activities and initiatives by local authorities. (Questionnaire and results) Improvement and Development Agency, 2000) and 2002 (Allman et al., Climate Change: a survey of local authorities, Local Government Association, 2002) were compared. Progress in implementing the International Council for Local Environmental Initiatives (ICLEI) five-step methodology (ICLEI, Local Government Implementation of Climate Protection—report to the United Nations, International Council for Local Environmental Initiatives, 1997) was used to identify the 'successful' local authorities. The barriers faced by these authorities were then compared with those faced by the remaining local authorities.

Most local authorities are not making substantial progress. However, a small number have successfully prepared greenhouse gas emissions inventories, developed strategies and implemented adaptation and greenhouse gas reduction measures. These successful authorities have made progress despite the fact that addressing climate change is not a legal requirement.

Their success is due to three key factors. Firstly, they have recognised the secondary benefits of tackling climate change, e.g. potential employment, improved quality of life and reduction in fuel poverty. Secondly, they have the strong political, professional and technical support necessary to champion climate change activities. Finally, they have worked in partnership with utilities, private, public and voluntary groups to raise the finance needed to implement measures both to adapt to climate change and to reduce greenhouse gas emissions.  相似文献   
65.
Declines in populations of and reproductive success of wood storks and other wading birds have occurred in the Florida Everglades over the past several decades. These declines have been concurrent with major changes in the Everglades’ landscape characteristics. Among the plausible hypotheses that relate to landscape change are the following: (1) general loss of habitat; (2) heavy loss of specific habitat, namely, short-hydroperiod wetlands that provide high prey availability early in the breeding season; and (3) an increase in frequency of major drying out of the central slough areas, which can affect prey availability late in the breeding season. These three hypotheses were compared using an individual-based model of wood stork (Mycteria americana) reproduction. This model simulated the behavior and energetics of each individual wood stork in a breeding colony on 15-min time intervals. Changes in water depth and prey availability occurred on daily time steps. Simulation results showed a threshold response in reproductive success to reduction of wetland heterogeneity. Model comparisons in which (1) only short-hydroperiod wetlands were removed and (2) wetlands of both long and short hydroperiods were removed showed that, for the same loss of total area, the specific habitat removal caused a much greater reduction in wood stork reproduction, indicating hypothesis 2 may be a more likely explanation than hypothesis 1. Reduction of initial prey availability in the central slough areas (simulating frequent drying; hypothesis 3) reduced fledging success by an average of more than 90% in the model.  相似文献   
66.
ABSTRACT: The biogeochemistry of a coastal old-growth forested watershed in Olympic National Park, Washington, was examined. Objectives were to determine: (1) concentrations of major cations and anions and dissolved organic C (DOC) in precipitation, throughfall, stemflow, soil solution and the stream; (2) nutrient input/output budgets; and (3) nutrient retention mechanisms in the watershed. Stemilow was more acidic (pH 4.0–4.5) than throughfall (pH 5.1) and precipitation (pH 5.3). Organic acids were important contributors to acidity in throughfall and stemflow and tree species influenced pH. Soil solution pH averaged 6.2 at 40 cm depth. Stream pH was higher (7.6). Sodium (54.0 μeq L-1) and Cl (57.6 μeq L?1) were the dominant ions in precipitation, reflecting the close proximity to the ocean. Throughfall and stemflow were generally enriched in cations, especially K. Cation concentrations in soil solutions were generally less than those in stemilow. Ion concentrations increased in the stream. Dominant ions were Ca (759.7 μeq L?1), Na (174.4 μeq L?1), HCO3 (592.0 μeq L?1), and SO4 (331.5 μeq L?1) with seasonal peaks in the fall. Bedrock weathering strongly influenced stream chemistry. Highest average NO3 concentrations were in the stream (5.2 μeq L?1) with seasonal peaks in the fall and lowest concentrations in the growing season. Nitrogen losses were similar to inputs; annual inputs were 4.8 kg/ha (not including fixation) and stream losses were 7.1 kg/ha. Despite the age and successional status of the forest, plant uptake is an important N retention mechanism in this watershed.  相似文献   
67.
68.
Wetlands in the Rainwater Basin in Nebraska are vulnerable to sediment accumulation from the surrounding watershed. Sediment accumulation has a negative impact on wetland quality by decreasing the depth and volume of water stored, and the plant community species composition and density growing in the wetland. The objective of this study was to determine the amount of sediment that has accumulated in five selected wetlands in the Rainwater Basin in Nebraska. Soil cores were taken at five or six locations along transects across each wetland. This study used the fly ash, which is generated by coal‐burning locomotives that were present generally in the late 1800s and early 1900s, as a marker to quantify the sediment deposition rates. The cores were divided into 5 cm sections and the soils were analyzed using a fly ash extraction and identification technique. Results indicate that the average depth of sediment ranged from 23.00 to 38.00 cm. The annual average depth of sediment accumulation ranged from 0.18 cm/yr to 0.29 cm/yr. The annual sediment accumulation rate from both wind erosion and water erosion in these five sampling wetlands was between 1.946 and 3.225 kg/m2/yr. The results of this research can be used to develop restoration plans for wetlands. The fly ash testing technology can also be applied to other areas with the railroads across the United States.  相似文献   
69.
The southern interior ecoprovince (SIE) of British Columbia, Canada represents the northernmost extent of the great western North American deserts, it is experiencing some of the nation's fastest economic and population growth making it one of Canada's most water‐stressed regions, and it includes two headwater basins of the transboundary (Canada‐US) Columbia River. Statistical trend analyses were performed on 90‐year regional indicator time series for annual conditions in observed temperature, precipitation, and streamflow reflecting the three major SIE river basins: the Thompson, and transboundary Okanagan and Similkameen. Results suggest that regional climate has grown warmer and wetter, but with little net impact on total water supply availability. The outcome might reflect mutual cancellation of increases in precipitation inputs vs. evapotranspiration losses. Conclusions appeared largely insensitive to low‐pass data filtering, Pacific Decadal Oscillation effects, or solar output variability. Ensemble historical global climate model runs over the same time interval support this absence of appreciable trend in regionally integrated annual runoff volume, but a possible mismatch in precipitation results suggests a direction for further study. Overall, while important changes in hydrologic timing and extremes are likely occurring here, there is limited evidence for a net change in overall water supply availability over the last century.  相似文献   
70.
The aim of this study was the development of analytical methods for the simultaneous determination of 25 selected pharmaceuticals, metabolites, and pesticides, belonging to the various chemical classes, in river sediments and their corresponding surface and ground water with the purpose of monitoring the contamination levels. The methods were based on the solid-phase extraction as the sample preparation method for water samples, and the ultrasonic solvent extraction for the sediment samples, followed by the liquid chromatography–tandem mass spectrometry. High recoveries were achieved for extraction from both water and sediment samples for the majority of analytes. Low limits of detection were achieved for all investigated compounds in the water sample (1–5 ng L?1) as well as in the sediment (1–3 ng g?1). Applicability of the developed methods was demonstrated by determination of pharmaceutical and pesticide residues in 30 surface water, 44 groundwater, and 5 sediment samples from the Danube River Basin in Serbia. Sixty percent of target compounds were detected in environmental samples. The most frequently detected analytes in river sediments were the pesticides dimethoate and atrazine, while carbamazepine and metamizole metabolites 4-AAA and 4-FAA were the most frequently found in water samples.  相似文献   
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