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11.
Environmental planners often propose tourism as a means of financing programmes to protect significant environmental areas. Surveys of tourists can provide useful information about the significance of environmental problems, trade-offs among policy objectives, willingness to pay (WTP) for protection programmes and preferences for different payment mechanisms. In Khanh Hoa Province, the provincial People's Committee, the Ministry of Fisheries and the World Conservation Union are working to implement Viet Nam's first marine protected area (MPA) in Nha Trang Bay. This paper reports the results of a survey of local and other Vietnamese and foreign tourists to islands that will be included in the MPA. The majority of respondents thought rubbish on the beaches, water pollution and vendors on beaches were problems and that the MPA was a good idea. Foreign tourists were significantly more likely to perceive environmental problems than were Vietnamese tourists, and persons who agreed there were environmental problems were significantly more likely to support the concept of an MPA, despite the potential for possible economic effects with distributive consequences. WTP for protection was modest and positively correlated with education and income. Although foreign tourists were on average willing to pay more, a larger proportion of Vietnamese tourists were willing to pay some amount to support the MPA. Analyses indicate that changes in income and education expected with economic development will increase both awareness of problems and WTP for protection. The results of this analysis are both encouraging and cautionary. The need for an MPA is clearly recognized by most tourists, and most tourists are willing to pay small fees to support the MPA. Given that education has significant impacts on both perceptions of problems and WTP, educational programmes may be an effective strategy for managing the competing objectives of protection and use. 相似文献
12.
Preferred modes of travel among older adults: What factors affect the choice to walk instead of drive? 总被引:1,自引:0,他引:1
Rebecca B. Naumann Author Vitae Ann M. Dellinger Author Vitae Author Vitae Amy E. Bonomi Author Vitae Author Vitae Robert S. Thompson Author Vitae 《Journal of Safety Research》2009,40(5):395-36
Introduction
There are many factors that influence older adults' travel choices. This paper explores the associations between mode of travel choice for a short trip and older adults' personal characteristics.Methods
This study included 406 drivers over the age of 64 who were enrolled in a large integrated health plan in the United States between 1991 and 2001. Bivariate analyses and generalized linear modeling were used to examine associations between choosing to walk or drive and respondents' self-reported general health, physical and functional abilities, and confidence in walking and driving.Results
Having more confidence in their ability to walk versus drive increased an older adult's likelihood of walking to make a short trip by about 20% (PR = 1.22; 95% CI: 1.06-1.40), and walking for exercise increased the likelihood by about 50% (PR = 1.53; 95% CI = 1.22-1.91). Reporting fair or poor health decreased the likelihood of walking, as did cutting down on the amount of driving due to a physical problem.Discussion
Factors affecting a person's decision to walk for exercise may not be the same as those that influence their decision to walk as a mode of travel. It is important to understand the barriers to walking for exercise and walking for travel to develop strategies to help older adults meet both their exercise and mobility needs. Impact on Industry: Increasing walking over driving among older adults may require programs that increase confidence in walking and encourage walking for exercise. 相似文献13.
Naumann RB Dellinger AM Anderson ML Bonomi AE Rivara FP 《Journal of Safety Research》2012,43(2):141-144
PurposeThis study compared the healthcare utilization and costs for specific types of medical services among older adult women who currently drive and those who no longer drive.MethodsThis study included 347 women aged 65 or older who were either former (had stopped driving) or current drivers, randomly sampled from a large U.S. health plan to participate in a telephone survey, and who had automated health records with healthcare utilization and cost data. Bivariate analyses and generalized linear modeling were used to examine associations between driving status and healthcare utilization and costs.ResultsAdjusting for age, income, and marital status, former drivers were more likely than current drivers to use mental health care services (RR = 3.37; 95% CI: 1.03, 10.98). Former drivers also tended to use more inpatient (RR = 1.85; 95% CI: 0.88, 3.87) and emergency services (RR = 1.89; 95% CI: 0.96, 3.70), but results did not reach statistical significance. Total annual healthcare costs in 2005 were almost twice as high for former drivers compared with current drivers ($13,046 vs. $7,054; mean difference = $5,992; 95% CI: -$360, $12,344), although this relationship was not statistically significant (CR = 1.61; 95% CI: 0.88, 2.96).Impact on IndustryFormer drivers were more than three times as likely as current drivers to use mental health services, and tended to use more emergency and inpatient services. Further research on factors that potentially mediate the relationship between driving status and health service use is warranted. 相似文献
14.
Jordan Ann Kevan de Haan 《The Environmentalist》2008,28(3):171-173
Currently, there is a need for a better multidisciplinary education system for tropical conservation, as well as a need for
more people from developing countries to receive such improved education and training. If this combination is achieved, universities
in both developed and developing nations will likely produce graduates who are better prepared for jobs involving non-academic
tropical conservation initiatives and, simultaneously produce graduates who may be better accepted as conservationists in
tropical destinations. 相似文献
15.
In this paper we question the importance of social capital as a primary indicator of a community's ability to engage in sustainable development as social capital can have both hindering and facilitating effects. We suggest that actor agency allows an individual or group to increase access to other critical forms of capital to overcome barriers and solve problems. We present 'bonding' social capital consisting of strong network ties as a negative in excess quantity as it can lead to the enforcement of social norms that hinder innovative change, and 'bridging' social capital consisting of weak network ties as a benefit that allows actors to bring about critical social changes. Communities achieve agency through a dynamic mix of bonding and bridging ties. We close with suggestions for fostering community agency and flag the need for further research in this area. 相似文献
16.
Assessment of GM Crops in Commercial Agriculture 总被引:1,自引:0,他引:1
The caliber of recent discourse regarding geneticallymodified organisms (GMOs) has suffered from a lack of consensuson terminology, from the scarcity of evidence upon which toassess risk to health and to the environment, and from valuedifferences between proponents and opponents of GMOs. Towardsaddressing these issues, we present the thesis that GM should bedefined as the forcible insertion of DNA into a host genome,irrespective of the source of the DNA, and exclusive ofconventional or mutation breeding.Some defenders of the commercial use of GMOs have referred to thescientific work of GMO critics as ``junk science.' Such a claim isfalse and misleading, given that many papers critical of both theutility and safety of GMOs have been published in peer reviewedjournals by respected scientists. In contrast, there is a dearthof peer reviewed work to substantiate the frequently heardassertions of either safety or utility in GMOs. The polarity,which now characterizes much of the public discourse on GMOs,reflects not simply scientific disagreement, but alsodisagreement in underlying value assumptions. Value differencesstrongly affect the assessment of both benefit and harm fromGMOs.The concept of substantial equivalence occupies a pivotalposition in the GMO risk assessment process that is used in bothCanada and the US. A GMO judged to be substantially equivalent toa conventional product – as have all submissions to date – ispresumed to be safe enough for commercialization. The conclusionof safety – from both human health and environmental perspectives– should be based on scientific evidence, corroborated by actualexperimentation. However, regulators infer safety largely fromassumptions-based reasoning, with little or no experimentalvalidation. The judgement of safety because of substantialequivalence is a dubious argument by analogy. 相似文献
17.
Cordylanthus palmatus is a hemiparasitic annual of the family Scrophulareacae. It is on both the federal and state lists of endangered species. Only four widely separated populations remain, all of them in alkali sinks, where the plant thrives in saline-sodic soils. The largest population is at Springtown, Alameda County, California. This article reports on efforts to develop a management plan for both the plant and the alkali sink ecosystem. The plan is based on: (1) characterization of hydrology, soils and geomorphology of the site; (2) characterization of the land use impacts to the site; (3) analysis of plant distribution in relation to gradients of elevation and soil chemistry; (4) studies on water potential and water stress inCordylanthus palmatus and associated species. On the basis of this plan, both the State of California and private groups are cooperating to create, restore, and manage a preserve in the Springtown Alkali Sink. 相似文献
18.
Recovery of temperate-stream fish communities from disturbance: A review of case studies and synthesis of theory 总被引:3,自引:0,他引:3
Naomi E. Detenbeck Philip W. DeVore Gerald J. Niemi Ann Lima 《Environmental management》1992,16(1):33-53
To evaluate the relative effect of autecologic factors, site-specific factors, disturbance characteristics, and community
structure on the recovery of temperate-stream fish communities, we reviewed case histories for 49 sites and recorded data
on 411 recovery end points. Most data were derived from studies of low-gradient third- or fourth-order temperate streams located
in forested or agricultural watersheds. Species composition, species richness, and total density all recovered within one
year for over 70% of systems studied. Lotic fish communities were not resilient to press disturbances (e.g., mining, logging,
channelization) in the absence of mitigation efforts (recovery time >5 to >52 yr) and in these cases recovery was limited
by habitat quality. Following pulse disturbances, autecological factors, site-specific factors, and disturbance-specific factors
all affected rates of recovery. Centrarchids and minnows were most resilient to disturbance, while salmonid populations were
least resilient of all families considered. Species within rock-substrate/nest-spawning guilds required significantly longer
time periods to either recolonize or reestablish predisturbance population densities than did species within other reproductive
guilds. Recovery was enhanced by the presence of refugia but was delayed by barriers to migration, especially when source
populations for recolonization were relatively distant. Median population recovery times for systems in which disturbances
occurred during or immediately prior to spawning were significantly less than median recovery times for systems in which disturbances
occurred immediately after spawning. There was little evidence for the influence of biotic interactions on recovery rates. 相似文献
19.
Analysis of bank erosion on the Merced River,Yosemite Valley,Yosemite National Park,California, USA 总被引:1,自引:0,他引:1
Channel changes from 1919 to 1989 were documented in two study reaches of the Merced River in Yosemite National Park through
a review of historical photographs and documents and a comparison of survey data. Bank erosion was prevalent and channel width
increased an average of 27% in the upstream reach, where human use was concentrated. Here, trampling of the banks and riparian
vegetation was common, and banks eroded on straight stretches as frequently as on meander bends. Six bridges in the upper
reach constrict the channel by an average of 38% of the original width, causing severe erosion. In the downstream control
reach, where human use was minimal, channel widths both decreased and increased, with a mean increase of only 4% since 1919.
Bank erosion in the control reach occurred primarily on meander bends. The control reach also had denser stands of riparian
vegetation and a higher frequency of large woody debris in channels. There is only one bridge in the lower reach, located
at the downstream end. Since 1919, bank erosion in the impacted upstream reach contributed a significant amount of sediment
(74,800 tonnes, equivalent to 2.0 t/km2/yr) to the river. An analysis of 75 years of precipitation and hydrologic records showed no trends responsible for bank erosion
in the upper reach. Sediment input to the upper reach has not changed significantly during the study period. Floodplain soils
are sandy, with low cohesion and are easily detached by lateral erosion. The degree of channel widening was positively correlated
with the percentage of bare ground on the streambanks and low bank stability ratings. Low bank stability ratings were, in
turn, strongly associated with high human use areas. Channel widening and bank erosion in the upper reach were due primarily
to destruction of riparian vegetation by human trampling and the effect of bridge constrictions on high flow, and secondarily
to poorly installed channel revetments. Several specific recommendations for river restoration were provided to park management. 相似文献
20.
E. Ann Clark 《Journal of Agricultural and Environmental Ethics》1988,1(4):275-289
Changes in global patterns of grain production have affected the profitability of commercial, cash-crop agriculture in North America. The current financial crisis has highlighted a perceived conflict between the priorities of (1) strengthening net farm profit, (2) maintaining the productive potential of the land base, (3) enhancing the health and cohesiveness of the agricultural community, and (4) addressing societal demands for safe foodstuffs. Reducing input costs by reducing the need for privately owned machinery can minimize the scale-dependence of agricultural practices, as illustrated with examples involving silage and intensively managed pasture in Ontario. This approach could improve farming opportunities for nontraditional, part-time farmers, and at the same time, create a niche for professional custom operators and managers. Enhancing the viability of nontraditional farm operations, a historically neglected component of the farming community, as well as commercial farms is viewed as one approach to sustaining and improving both the agricultural land base and the agricultural community. Applying resource-extensive rather than resource-intensive approaches to forage management reveals that these apparently divergent priorities are, in fact, interlocking pieces of the same puzzle. 相似文献