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31.
Most Great River ecosystems (GREs) are extensively modified and are not receiving adequate protection to prevent further habitat degradation and loss of biotic integrity. In the United States, ecological monitoring and assessment of GREs has lagged behind streams and estuaries, and the management of GREs is hampered by the lack of unbiased data at appropriate spatial scales. Properties of GREs that make them challenging to monitor and assess include difficult sample logistics and high habitat diversity. The U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program (EMAP) has developed a comprehensive, regional-scale, survey-based monitoring approach to assessment of streams and estuaries, but has not yet conducted research on applying these tools to GRE monitoring. In this paper we present an overview of an EMAP research project on the Upper Missouri River (UMR). We summarize the assessment objectives for the study, the design for selecting sample locations, the indicators measured at these sites and the tools used to analyze data. We present an example of the type of statements that can be made with EMAP monitoring data. With modification, the set of methodologies developed by EMAP may be well suited for assessment of GREs in general.  相似文献   
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Viewpoint     
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ABSTRACT: The purpose of this paper is to examine the correlates of attitudes toward alternative uses which could have been made of public resources employed to construct a multipurpose reservoir. A sample of 303 adult residents of a rural community impacted by lake construction was asked to evaluate several alternative development options which could have been implemented in lieu of the lake project. The alternative options evaluated were: rural industrialization, keeping land in agriculture and forests, improving public services, building a state or national park, drilling water wells for urban water supply, aid to small business, helping poor people, building several smaller impoundments, and private recreation development. The findings revealed the local people preferred the lake project to every option except keeping the land in agriculture and forest. Even this option was not strongly supported when compared with the lake project. Socio-demographic, attitude, and cost assessment factors were investigated using a “vested interest” perspective for hypotheses development. These findings demonstrated that costs and benefits were relatively good predictors of attitudes toward alternative development options and were supportive of the theoretical perspective advanced in this paper.  相似文献   
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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   
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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   
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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   
38.
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   
39.
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   
40.
Despite compelling reasons to involve nonscientists in the production of ecological knowledge, cultural and institutional factors often dis-incentivize engagement between scientists and nonscientists. This paper details our efforts to develop a biweekly newspaper column to increase communication between ecological scientists, social scientists, and the communities within which they work. Addressing community-generated topics and written by a collective of social and natural scientists, the column is meant to foster public dialog about socio-environmental issues and to lay the groundwork for the coproduction of environmental knowledge. Our collective approach to writing addresses some major barriers to public engagement by scientists, but the need to insert ourselves as intermediaries limits these gains. Overall, our efforts at environmental communication praxis have not generated significant public debate, but they have supported future coproduction by making scientists a more visible presence in the community and providing easy pathways for them to begin engaging the public. Finally, this research highlights an underappreciated barrier to public engagement: scientists are not merely disconnected from the public, but also connected in ways that may be functional for their research. Many field scientists, for example, seek out neutral and narrowly defined connections that permit research access but are largely incompatible with efforts to address controversial issues of environmental governance.  相似文献   
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