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581.
Michael C. Morris 《Journal of Agricultural and Environmental Ethics》2000,13(3-4):205-217
Fly strike is a painful conditioncaused by live maggots eating at the flesh of sheep.Remedies for this disorder are traumatic, with sheepundergoing painful mulesing and tail dockingoperations to protect against flystrike. In an attemptto find control solutions and to understand thedisorder, Australasian researchers increase sheepsuffering by conducting experiments that artificiallyinduce fly strike. Some of these experiments have noapplication in prevention and control of fly strike.Many others could be modified or replaced with lesspainful techniques.Anecdotal evidence through communication withorganic farmers suggests that fly strike is largelypreventable if farmers keep sheep healthy and inspectthem regularly. Some organic farmers have largelyeliminated fly strike from their farm. Investigationson fly strike control using non-intrusive techniquesare also progressing in Australasia and the UnitedKingdom.Since it is possible to conduct useful research andto run profitable farms with little or no fly strike,much of the current management, research and policy onsheep farming is ethically questionable even to thoseholding the moderate view that animals can be used forhuman purposes providing suffering is kept to aminimum. Sheep farmers will need to take animalwelfare problems into consideration. Greatercommunication among researchers needs to be encouragedto prevent unnecessary duplication of experiments.International trade regulations will also need toallow trade barriers based on animal welfareconcerns. 相似文献
582.
Jonathan M. Gallimore Barbara B. Brown Carol M. Werner 《Journal of environmental psychology》2011,31(2):184-191
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions. 相似文献
583.
Marshall Flug Robert H. Montgomeiy 《Journal of the American Water Resources Association》1988,24(5):1073-1081
ABSTRACT: A basic problem in the management of rivers has been how to balance the tradeoffs between instream and out-of-stream uses. Traditionally, the problem has been addressed by optimizing the economic benefits of flow diversions and regulated releases with instream uses as a flow constraint. An alternative method is to model the effect different river flows have on various recreational uses (e.g., boating, fishing) and then use the results as an additional function or piece of information to determine river project operations and benefits. A methodology that is based on multiobjective decision theory and that relates instream recreational preferences to river flow is proposed. The methodology consists of determining, standardizing, and combining recreational benefit functions, and incorporating potential sources of uncertainty into an estimate of total instream benefits. Thus different types of flow patterns, resulting from reservoir regulation (out-of-stream water uses), can be analyzed to determine their potential instream impact. The methodology is applied to the New River Gorge, West Virginia, which has been designated as a National River. 相似文献
584.
Peter N. Swift 《Environmental management》1993,17(1):83-97
The United States Department of Energy is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for
the disposal of transuranic wastes generated by defense programs. Because changes in climate during the next 10,000 years
(10 ka) may affect performance of the repository, an understanding of long-term climate variability is essential for evaluating
regulatory compliance.
Fluctuations in global climate corresponding to glaciation and deglaciation of the northern hemisphere have been regular in
both frequency and amplitude for at least 780 ka. Coolest and wettest conditions in the past have occurred at the WIPP during
glacial maxima, when the North American ice sheet reached its southern limit roughly 1200 km north of the WIPP and deflected
the jet stream southward. Average precipitation in southeastern New Mexico during the last glacial maximum 22-18 ka before
present (BP) was approximately twice that of the present. Driest conditions (precipitation approximately 90% of present) occurred
6.5-4.5 ka BP, after the ice sheet had retreated to its present location. Wet periods of unknown duration have occurred since
the retreat of the ice sheet, but none have exceeded glacial conditions. Global climate models suggest that anthropogenic
climate changes (i.e., warming caused by an increased greenhouse effect) will not result in an increase in precipitation at
the WIPP. The climate of the last glacial maximum is therefore suitable for use as a cooler and wetter limit for variability
during the next 10 ka. 相似文献
585.
Dina E. Flockhart Chi Ho Sham Yan Xiao 《Journal of the American Water Resources Association》1993,29(6):957-964
ABSTRACT: Public awareness of the importance of protecting the nation's water supplies is growing. Recent studies have shown a substantial increase in the perceived value of protecting water supplies for future use. In the Northeast, much of the water supply comes from ground water. This paper examines three test cases, each with different approaches for using geographic information systems (GIS) for ground water protection planning. In Wellfleet, Massachusetts, build-out scenarios were used to support regulatory and land acquisition decisions for siting a public water supply well. In Hadley, Massachusetts, the focus was on a decision support model for septic suitability assessment in support of regulatory efforts and infrastructure expansion. For Cortland County, New York, an interactive graphic user interface was created to facilitate the manipulation and recombination of a large volume of data by county officials to target ground water pollution prevention efforts. As personal computers become more powerful and inexpensive, and GIS data become more readily available, community and county governments are turning to GIS as a tool for developing comprehensive resource protection plans. Once appropriate data are input, a GIS can effectively and efficiently be used to derive outcomes of various land use plans and regulations. 相似文献
586.
Riparian functions such as the recruitment of wood to streams take decades to recover after a clear-fell harvest to the stream edge. The implications of two sets of riparian management scenarios on the short- and long-term recruitment of wood to a hypothetical stream (central North Island, New Zealand) were compared through simulation modeling. In the first set (native forest buffer), a designated treeless riparian buffer was colonized by native forest species after a pine crop (Pinus radiata) had been harvested to the stream bank. In the second set (pine to native forest buffer), native forest species were allowed to establish under the pine canopy in a designated riparian buffer. In general, the volume of wood was greater in streams with wider buffers (5-m to 50-m) and this effect increased with forest age (800 years). The pine to native forest buffer supplied more wood to the stream more quickly, and matched the long-term supply to the stream from the native forest buffer. For the native forest buffer, total wood volume was minimal for the first 70 years and then increased uniformly for the remainder of the simulation. In contrast, the pine to native forest buffer produced a bimodal response in total wood volume with the initial sharp peak at year 100 attributed to pine recruitment and a second more gradual peak lasting for the rest of the simulation, which was similar to levels in the native forest simulations. These results suggest that existing plantations could be an important source of wood to the stream during the first 100+ years of native forest development. 相似文献
587.
Mike R. Scarsbrook Chris G. McBride Graham B. McBride Graham G. Bryers 《Journal of the American Water Resources Association》2003,39(6):1435-1447
ABSTRACT: Associations between the El Nino Southern Oscillation (ENSO) climate pattern and temporal variability in flow and 12 water quality variables were assessed at 77 river sites throughout New Zealand over a 13‐year period (1989 through 2001). Trends in water quality were determined for the same period. All 13 variables showed statistically significant linear regression relationships with values of the Southern Oscillation Index (SOI). The strongest relationships were for water temperature (mean R2= 0.20), dissolved reactive phosphorus (0.18), and oxidized nitrogen (0.17). The association with SOI varied by climate region. The observed patterns were generally consistent with known ENSO effects on New Zealand rainfall and air temperature. Trends in water quality variables for the periods 1989 through 1993, 1994 through 1998, and 1989 through 1998 were reasonably consistent with trends in SOI, even when the influence of river flow was removed from the data. This suggests that SOI effects on water quality are not necessarily a direct consequence of changes in flow associated with rainfall variation. In addition, both Baseline (32 upstream) and Impact (45 downstream) sites showed similar trends, indicating that changes in management were not directly responsible. We conclude that interpretation of long term water quality datasets in rivers requires that climate variability be fully acknowledged and dealt with explicitly in trend analyses. 相似文献
588.
Caruso BS 《Environmental management》2006,37(6):840-861
Ecological restoration is increasingly becoming a primary component of broader environmental and water resources management
programs throughout the world. The New Zealand Department of Conservation implemented Project River Recovery (PRR) in 1991
to restore unique braided gravel-bed river and wetland habitat in the Upper Waitaki Basin in New Zealand’s high country of
the South Island, which has been severely impacted by hydroelectric power development. These braided rivers are highly dynamic,
diverse, and globally important ecosystems and provide critical habitat to numerous native wading and shore bird species,
including several threatened species such as the black stilt. The objective of this study was to review and summarize PRR
after more than 10 years of implementation to provide information and transfer knowledge to other nations and restoration
programs. Site visits were conducted, discussions were held with key project staff, and project reports and related literature
were reviewed. Primary components of the program include pest plant and animal control, wetland construction and enhancement,
a significant research and monitoring component, and public awareness. The study found that PRR is an excellent example of
an ecological restoration program focusing on conserving and restoring unique habitat for threatened native bird species,
but that also includes several secondary objectives. Transfer of knowledge from PRR could benefit ecological restoration programs
in other parts of the world, particularly riverine floodplain and braided river restoration. PRR could achieve even greater
success with expanded goals, additional resources, and increased integration of science with management, especially broader
consideration of hydrologic and geomorphologic effects and restoration opportunities. 相似文献
589.
The recent events at Chernobyl have again brought the issues of nuclear safety to the forefront of the nuclear power debate. Fortunately, our experience with such incidents has been very limited, but it is important to learn as much as possible from such events so as to minimize the cost and effect of any other nuclear incidents, be they small or large. Much of the discussion about the possible effects of nuclear incidents has centered around the human cost in terms of health. While this is undoubtedly of paramount concern, the effect of the release of radiation from Chernobyl on the agricultural resource base in Europe can provide valuable insights on how to reduce the costs associated with the contamination of agricultural areas. This article outlines some of the lessons that can be learned using the livestock-raising industry in northern Wales as an example. 相似文献
590.
This paper reports on a nationwide survey of environmental farm plan programmes and plan characteristics, towards determining New Zealand's (NZ's) capability and eligibility for reporting on the Organisation for Economic Cooperation and Development's (OECD) environmental whole farm management plan agri-environmental indicator. Considerations regarding the validity of the indicator are discussed. Environmental farm planning in NZ is widespread, fragmented, and diverse. Nine of NZ's 16 regional authorities have environmental farm plan programmes involving 20 different types of environmental farm plans. Potentially half of NZ's total area of farmland is included, but this is reduced by limited and selective use of environmental farm plans as policy instruments. Three authorities are capable of readily reporting the number and coverage of their environmental farm plans; six would need to manually compile the information. Compliance monitoring is mostly informal, but necessary for checking the implementation of plan works and actions. Eligibility of NZ environmental farm plans cannot be determined until the OECD define acceptance standards. A contemporary definition of environmental farm plans is proposed, along with additional criteria necessary to ensure such plans are credible indicators of issue ownership, adoption of best management practice, and landscape changes intended to improve environmental quality. 相似文献