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851.
Black R 《Disasters》2003,27(2):95-108
Notable strides have been made in recent years to develop codes of conduct for humanitarian intervention in conflicts on the part of international NGOs and UN organisations. Yet engagement by the academic and broader research communities with humanitarian crises and ongoing complex political emergencies remains relatively ad hoc and unregulated beyond the basic ethical guidelines and norms developed within universities for research in general, and within the governing and representative bodies of particular academic disciplines. This paper draws on a case study of research on humanitarian assistance to Liberia during that country's civil war from 1989 to 1996. The difficulties faced by humanitarian agencies in Liberia led to the development of two key sets of ethical guidelines for humanitarian intervention: the Joint Policy of Operations (JPO) and Principles and Policies of Humanitarian Operations (PPHO). This paper seeks to address what lessons, if any, these ethical guidelines, together with different experiences of conducting research in war-torn Liberia, can provide in terms of the role of academic researchers--and research itself--in humanitarian crises. 相似文献
852.
The US Clean Water Act and habitat replacement: evaluation of mitigation sites in Orange County,California, USA 总被引:2,自引:2,他引:0
Both permit requirements and ecological assessments have been used to evaluate mitigation success. This analysis combines
these two approaches to evaluate mitigation required under Section 404 of the United States Clean Water Act (CWA) and Section
10 of the Rivers and Harbors Act, which allow developers to provide compensatory mitigation for unavoidable impacts to wetlands.
This study reviewed permit files and conducted field assessments of mitigation sites to evaluate the effectiveness of mitigation
required by the US Army Corps of Engineers for all permits issued in Orange County, California from 1979 through 1993. The
535 permit actions approved during this period allowed 157 ha of impacts. Mitigation was required on 70 of these actions,
with 152 ha of enhanced, restored, and created habitat required for 136 ha of impacts. In 15 permit actions, no mitigation
project was constructed, but in only two cases was the originally permitted project built; the two cases resulted in an unmitigated
loss of 1.6 ha. Of the remaining 55 sites, 55% were successful at meeting the permit conditions while 11% failed to do so.
Based on a qualitative assessment of habitat quality, only 16% of the sites could be considered successful and 26% were considered
failures. Thus, of the 126 ha of habitat lost due to the 55 projects, only 26 ha of mitigation was considered successful.
The low success rate was not due to poor enforcement, although nearly half of the projects did not comply with all permit
conditions. Mitigation success could best be improved by requiring mitigation plans to have performance standards based on
habitat functions. 相似文献
853.
Richard F. Hadley William W. Emmett 《Journal of the American Water Resources Association》1998,34(3):629-637
ABSTRACT: A flood-control dam was completed during 1979 on Bear Creek, a small tributary stream to the South Platte River in the Denver, Colorado, area. Before and after dam closure, repetitive surveys between 1977 and 1992 at five cross sections downstream of the dam documented changes in channel morphology. During this 15-year period, channel width increased slightly, but channel depth increased by more than 40 percent. Within the study reach, stream gradient decreased and median bed material sizes coarsened from sand in the pools and fine gravel on the rime to a median coarse gravel throughout the reach. The most striking visual change was from a sparse growth of streamside grasses to a dense growth of riparian woody vegetation. 相似文献
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857.
Cost-effective use of permeable reactive barriers for groundwater treatment requires properly estimating the amount of reactive material required and choosing the best means of emplacing it. The weight of reactive material per unit cross section of the plume can be estimated from laboratory reaction kinetics data and basic knowledge of the plume and the remediation goals. This parameter has implications regarding the choice of permeable barrier design and emplacement method. The use of tremie tubes, trenching machines, high-pressure jetting, and deep soil mixing may be appropriate for different situations depending on the amount of reactive material required, the dimensions of the plume, and other factors. The specific application considered here is the use of granular iron to treat groundwater contaminated with chlorinated solvents. 相似文献
858.
Gerald T. Ankley Nelson A. Thomas Dominic M. Di Toro David J. Hansen John D. Mahony Walter J. Berry Richard C. Swartz Robert A. Hoke A. Wayne Garrison Herbert E. Allen Christopher S. Zarba 《Environmental management》1994,18(3):331-337
Due to anthropogenic inputs, elevated concentrations of metals frequently occur in aquatic sediments. In order to make defensible
estimates of the potential risk of metals in sediments and/or develop sediment quality criteria for metals, it is essential
to identify that fraction of the total metal in the sediments that is bioavailable. Studies with a variety of benthic invertebrates
indicate that interstitial (pore) water concentrations of metals correspond very well with the bioavailability of metals in
test sediments. Many factors may influence pore water concentrations of metals; however, in anaerobic sediments a key phase
controlling partitioning of several cationic metals (cadmium, nickel, lead, zinc, copper) into pore water is acid volatile
sulfide (AVS). In this paper, we present an overview of the technical basis for predicting bioavailability of cationic metals
to benthic organisms based on pore water metal concentrations and metal-AVS relationships. Included are discussions of the
advantages and limitations of metal bioavailability predictions based on these parameters, relative both to site-specific
assessments and the development of sediment quality criteria. 相似文献
859.
Andrew D. Kliskey Christopher C. Hoogsteden Richard K. Morgan 《Journal of Environmental Planning and Management》1994,37(4):431-445
The paper examines the application of a spatial‐perceptual approach to the wilderness management issue of preserving natural ecological processes while also permitting appropriate wilderness use in protected areas. An approach to delimit the spatial extent of multiple perceptions of wilderness held by backcountry users is used—the wilderness perception mapping (WPM) methodology. The results obtained from employing the WPM.methodology are considered for the North West Nelson region of New Zealand. The map product provides new and useful information that has applicability to protected areas management. The role of WPM is discussed with reference to wilderness management in North West Nelson and New Zealand, and to protected areas management in general. The study demonstrates how a technology can be combined with a critical and sensible analysis of needs and procedures to give useful results, and highlights the value of applied interdisciplinary research. 相似文献
860.
Martin M. Karpiscak Richard G. Brittain Kennith E. Foster 《Journal of the American Water Resources Association》1994,30(2):329-334
ABSTRACT: In May 1993, a single-family home and adjoining information center opened to the public at the Desert Botanical Garden in Phoenix, Arizona. Desert House is designed as an example of what can be achieved today using available technology to improve residential water and energy efficiency. The home is expected to reduce water and energy use by 40 percent compared with that for the typical three-bedroom, single-family residence in the Phoenix area. Water-conserving features include: landscape design employing low-water use plants, minimum turf area, mulch around plants to reduce evaporation, and drip irrigation system; spa cover for evaporation reduction; rainwater harvesting; low-flow shower heads, faucets, and toilets; and graywater reuse system. The home will be occupied by a family and monitored for water and energy use by computer. Visitors are able to access real time water and energy use data about the home, as well as tour the information center, technical exhibits, surrounding landscape, and the home when it is open (one afternoon a week). 相似文献