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251.
Biodiversity offsets seek to compensate for residual environmental impacts of planned developments after appropriate steps
have been taken to avoid, minimize or restore impacts on site. Offsets are emerging as an increasingly employed mechanism
for achieving net environmental benefits, with offset policies being advanced in a wide range of countries (i.e., United States,
Australia, Brazil, Colombia, and South Africa). To support policy development for biodiversity offsets, we review a set of
major offset policy frameworks—US wetlands mitigation, US conservation banking, EU Natura 2000, Australian offset policies
in New South Wales, Victoria, and Western Australia, and Brazilian industrial and forest offsets. We compare how the frameworks
define offset policy goals, approach the mitigation process, and address six key issues for implementing offsets: (1) equivalence
of project impacts with offset gains; (2) location of the offset relative to the impact site; (3) “additionality” (a new contribution
to conservation) and acceptable types of offsets; (4) timing of project impacts versus offset benefits; (5) offset duration
and compliance; and (6) “currency” and mitigation replacement ratios. We find substantial policy commonalities that may serve
as a sound basis for future development of biodiversity offsets policy. We also identify issues requiring further policy guidance,
including how best to: (1) ensure conformance with the mitigation hierarchy; (2) identify the most environmentally preferable
offsets within a landscape context; and (3) determine appropriate mitigation replacement ratios. 相似文献
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253.
PROBLEM: While agricultural injury has been identified among the major causes of occupational injury mortality and morbidity, data have been limited pertinent to the magnitude, consequences, and potential risk factors for animal-related injuries -- a major source of morbidity among agricultural operations. METHODS: Demographics, exposure, and injury data were collected for 1999 and 2001 among agricultural households in a five-state region. Causal models facilitated survey design, data analyses, and interpretation of results; directed acyclic graphs guided multivariate modeling. RESULTS: From 7,420 households (84% response of eligible), a total of 5,045 injury events were reported; 1,016 (20.1%) were animal-related. Multivariate analyses revealed increased risks for those <20 years; residents of all states compared to Minnesota; all age groups compared to 0-4 years; >0 hours worked; and prior agricultural injury history. For those 20+ years, increased risks were identified for: South Dakota residents; males; >0 hours worked; and prior agricultural injury history. For those cases <20 and 20+ years of age, 58% and 46%, respectively, resulted in lost work time on their agricultural operations (31% and 50%, one week or more). CONCLUSIONS: Animal-related injury has a major impact on the agricultural industry. Results serve as a basis for interventions and further research. IMPACT ON INDUSTRY: The impact of animal-related injuries on the agricultural industry appears significant; among age groups <20 and 20+, 85% and 82%, respectively, had some resulting restriction. For all events combined, 29% and 30%, respectively, involved restriction from one week to 3+ months; 12% and 15% involved restriction for one month or more. Among those <20 and 20+ years of age, 58% and 46%, respectively, lost work time on their own agricultural operation as a result of injuries associated with their own operation; 22% and 15% lost one week or more. Moreover, of the non-agriculture-related injuries, 31% and 50% resulted in lost work time on their own operation; 15% and 28%, respectively, lost one week or more. Restrictions such as these can affect the productivity of the operation, resulting in financial impacts, especially on small operations that have few people to manage the required tasks. 相似文献
254.
Performance of Gd-doped Ti-based Sb-SnO2 anodes for electrochemical destruction of phenol 总被引:2,自引:0,他引:2
The performance of electrodes for the electro-catalytic decomposition of a model pollutant (phenol) was enhanced using Gd-doped Ti/SnO(2)-Sb electrodes prepared by a thermal deposition method. Phenol degradation followed first-order rate kinetics, with the maximum rate achieved using a 2% Gd doping level (molar ratio based on Gd:Sn) for tests conducted over a doping range of 1-10%. The first-order rate constant with 2% Gd was 0.044 min(-1), versus 0.026 min(-1) obtained with the control (plain Ti/SnO(2)-Sb). TOC removal and UV scans revealed that different intermediates were produced for different Gd contents, and that destruction efficiencies of these intermediates also varied with Gd doping levels of 1-5%. Electrodes were characterized by scanning electron microscopy, X-ray diffraction, electron dispersive spectrometry, and X-ray photon-electron spectroscopy. It is suggested that the state of specific active sites on the electrode surface and the oxygen transfer activity at the electrode/electrolyte interface affect the performance of anodes with different compositions. 相似文献
255.
Chemical solutions for greywater recycling 总被引:1,自引:0,他引:1
Pidou M Avery L Stephenson T Jeffrey P Parsons SA Liu S Memon FA Jefferson B 《Chemosphere》2008,71(1):147-155
Greywater recycling is now accepted as a sustainable solution to the general increase of the fresh water demand, water shortages and for environment protection. However, the majority of the suggested treatments are biological and such technologies can be affected, especially at small scale, by the variability in strength and flow of the greywater and potential shock loading. This investigation presents the study of alternative processes, coagulation and magnetic ion exchange resin, for the treatment of greywater for reuse. The potential of these processes as well as the influence of parameters such as coagulant or resin dose, pH or contact time were investigated for the treatment of two greywaters of low and high organic strengths. The results obtained revealed that magnetic ion exchange resin and coagulation were suitable treatment solutions for low strength greywater sources. However, they were unable to achieve the required level of treatment for the reuse of medium to high strength greywaters. Consequently, these processes could only be considered as an option for greywater recycling in specific conditions that is to say in case of low organic strength greywater or less stringent standards for reuse. 相似文献
256.
A 25-item scoring instrument was developed to measure perceptions of the extent to which performance appraisals are affected by organizational politics. The survey was administered to 157 francophone managers. A factor analysis revealed that the perceptions of the extent to which political considerations affect the appraisal an employee receives can be sensibly interpreted in terms of a single general factor. The internal consistency and test-retest reliability of the instrument was high. Moderate support was found for the instrument's convergent and discriminant validity. 相似文献
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259.
Toshihide Hamazaki Bruce C. Thompson Brian A. Locke Kenneth G. Boykin 《Journal of Environmental Planning and Management》2003,46(2):239-256
In developing conservation strategies, it is important to maximize effects of conservation within a specified land tract and to maximize conservation effects on surrounding area (ecological context). The authors proposed two criteria to select biotic entities for conservation foci: (1) the relative occurrence of fauna or flora in a tract is greater than that of an ecological context region; and (2) occurrence of the fauna or flora is relatively limited in the ecological context region. Using extensive spatial data on vegetation and wildlife habitat distribution, the authors identified strategic vegetation and fauna conservation foci for the 400 000 ha Fort Bliss military reservation in New Mexico and Texas relative to a 164 km radius ecological context region intersecting seven ecological zones and the predicted habitat distribution of 616 animal species. The authors set two specific criteria: (1) predicted area of a species' occurrence is <50% of the ecological context region; and (2) percentage of Fort Bliss intersecting the species' or vegetation community predicted areas in the ecological context region is >5% (Fort Bliss is 4.2% of the region). These criteria selected one vegetation class and 40 animal species. Further, these vegetation and animal foci were primarily located in two areas of Fort Bliss. Sensitivity analyses with other analytical radii corroborated the context radius used. Conservation of the two areas and associated taxa will maximize the contribution of Fort Bliss's conservation efforts in its ecological proximity. This relatively simple but information-rich process represents economical and defensible preliminary contextual analysis for detailed conservation planning. 相似文献
260.
Bruce Feldstein 《Disasters》1983,7(2):86-87
Accidents and sudden illness constitutes a major public health problem in many countries. Emergency medicine had developed as a vigorous new specialty in the U.S. and has fully integrated itself within the American medical and hospital system to provide improved emergency medical care. Emergency medicine plays a central role in disaster medical services, planning, and management and is the only specialty in American civilian medicine that includes disaster medicine as a primary field within its domain. Now that the basic framework of emergency medicine has been established, the American College of Emergency Physicians is implementing a nationwide training program on disaster planning and management for emergency physicians. 相似文献