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The introduction of national parks in areas where existing authorities have traditionally been responsible for developing policies, preparing plans and making decisions on development proposals, can be a threat to longstanding interests. This paper explores this problem by examining the struggle for control of planning in one of Scotland's first national parks, the Cairngorms. Recent research (McCarthy et al., 2002) has established the policy context for this investigation. Informed by research focusing on the consultation process which led to the establishment of the national park, this paper analyzes how alternative approaches to the allocation of planning powers were captured in competing storylines, around which polarized coalitions of interest formed. Opening such insights into the considerations that shape institutional design—a combination of contested problem framing and straightforward political struggles over the locus of regulatory power—starkly reveals the challenges to the new park authority as it seeks to establish consensus between conflicting interests. 相似文献
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Transport of lead and diesel fuel through a peat soil near Juneau, AK: a pilot study 总被引:3,自引:0,他引:3
Deiss J Byers C Clover D D'Amore D Love A Menzies MA Powell J Walter MT 《Journal of contaminant hydrology》2004,74(1-4):1-18
A set of peat column experiments was used to determine the transport potential of lead (Pb) and diesel range organics (DRO) in palustrine slope wetlands near Juneau, AK. This project is important to southeast Alaskan communities because limited land resources are forcing development of regional wetlands. This study was instigated by concerns that proposed modifications to a nearby rifle range using DRO-contaminated soil posed a potential risk to an anadromous fish-bearing stream 250 m from the site. Three pairs of peat columns were extracted from the rifle range for analysis, one pair along and two pairs across the natural bedding planes of the soil. One column in each pair was spiked with Pb and DRO and the other was used as a control. Approximately 1-year worth of water (171 cm) was passed through each column and leachate was collected at regular intervals. The results showed that substantial DRO transport only occurred along the bedding planes. Leads was surprisingly mobile, both along and across the bedding planes with estimated soil-water partition coefficients several orders of magnitude lower than commonly published values, probably because the peat was heavily Pb-loaded by lead from bullets and because the peat's acidic, organic-rich environment enhanced Pb mobility. The chemical outflow behavior agreed with a simple macropore transport model. These results underscore the need for caution when developing regional wetlands. 相似文献
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On the basis of a Solomon Islands case study, we report that tropical rainforests hitherto perceived as untouched, pristine, virgin, etc., are actually sites of former settlement, extensive forest clearance, and irrigated/swidden agriculture. An unusually wide range of sources--rainforest ecology, forest classification and mapping, ethnobotany, land-use history, oral traditions, ethnographic and archaeological observations--supports our conclusions. These observations have bearings for contemporary perspectives on scenarios for rainforest regeneration after logging. They also force a revision of certain assumptions concerning Melanesian prehistory and historical demography, and indicate that interdisciplinary links between botany, archaeology and social anthropology are needed to achieve a better appreciation of rainforest dynamics. 相似文献
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David L. Rick John W. Davis Shari L. Kram Michael N. Mang Tim D. Lickly 《Journal of Polymers and the Environment》1998,6(3):143-157
An epoxy-based thermoplastic polyester, poly(hydroxy ester ether), was incubated under aerobic conditions in a laboratory-scale compost system for 168 days to evaluate its potential for biodegradation. Radiolabeled test polymer [uniformly 14C ring-labeled, poly(hydroxy ester ether)] was incorporated into a mature compost and a sludge-amended compost at a loading of 3 mg test polymer/g compost. 14C-Cellulose was used as the positive control and a biologically inhibited control reactor was used to assess abiotic degradation of the test polymer. Degradation of the test polymer was assessed by measuring the amount of 14C-CO2 from each of the test reactors. In addition, at selected time intervals subsamples of the compost were collected and serially extracted with water, methanol, and dimethylformamide to monitor degradation of the 14C-test polymer and provide a partial characterization of the degradation intermediates. Extensive degradation of 14C-poly(hydroxy ester ether) was observed in the test reactors with degradation half-life of the parent polymer (t
1/2) of approximately 32 days. By the end of the study, only 2% of the total 14C activity in the test reactors was attributed to intact polymer, with most of the measurable 14C activity converted to either 14C-CO2 (26% of total 14C activity) or nonextractable products (accounting for 60% of the total activity). In contrast to the test reactors, only 3% of the 14C-poly(hydroxy ester ether) added to the biologically inhibited control reactor was mineralized to 14C-CO2. The results obtained from the microbially active and biologically inhibited compost systems indicate that the poly(hydroxy ester ether) polymer was degraded, at least in part, by a biologically mediated process. 相似文献
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R. Thomas. James James Martin Tim Wool P F Wang 《Journal of the American Water Resources Association》1997,33(3):661-678
ABSTRACT: The influence of sediment resuspension on the water quality of shallow lakes is well documented. However, a search of the literature reveals no deterministic mass-balance eutrophication models that explicitly include resuspension. We modified the Lake Okeechobee water quality model - which uses the Water Analysis Simulation Package (WASP) to simulate algal dynamics and phosphorus, nitrogen, and oxygen cycles - to include inorganic suspend. ed solids and algorithms that: (1) define changes in depth with changes in volume; (2) compute sediment resuspension based on bottom shear stress; (3) compute partition coefficients for ammonia and ortho-phosphorus to solids; and (4) relate light attenuation to solids concentrations. The model calibration and validation were successful with the exception of dissolved inorganic nitrogen species which did not correspond well to observed data in the validation phase. This could be attributed to an inaccurate formulation of algal nitrogen preference and/or the absence of nitrogen fixation in the model. The model correctly predicted that the lake is light-limited from resuspended solids, and algae are primarily nitrogen limited. The model simulation suggested that biological fluxes greatly exceed external loads of dissolved nutrients; and sediment-water interactions of organic nitrogen and phosphorus far exceed external loads. A sensitivity analysis demonstrated that parameters affecting resuspension, settling, sediment nutrient and solids concentrations, mineralization, algal productivity, and algal stoichiometry are factors requiring further study to improve our understanding of the Lake Okeechobee ecosystem. 相似文献
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