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41.
Ecotourism: The Santa Elena rainforest project 总被引:1,自引:0,他引:1
Stephen Wearing 《The Environmentalist》1993,13(2):125-135
Summary This paper outlines an ecotourism project undertaken in the Santa Elena community in the Monteverde region of Costa Rica. The community is seeking to establish a rainforest reserve on a parcel of land that has been permanently leased to their high school by the Costa Rican Government. The Community and Youth Challenge International are developing an ecotourism project that will provide a wider economic basis for the area and employment for students graduating from the high school. This project seeks to achieve sustainable development and fulfil the development requirements of the population surrounding the project. This is in the belief that it is only when conservation projects benefit local communities, and are set up with an infrastructure that vests control within local communities, that genuine ecotourism is achieved.Stephen Wearing is a lecturer in the School of Leisure and Tourism Studies at the University of Technology, Sydney, Australia, and he lectures and consults in the area of Tourism and Environmental Planning, and Parks Protected Area Management. His particular interest is in ecotourism projects with local communities. He is linked with Youth Challenge International and people interested in becoming involved or looking for assistance in projects can contact him at the above address. 相似文献
42.
43.
Healy S 《Journal of environmental management》2009,90(4):1644-1654
This article uses an analysis of the 'knowledge politics' of the Botany Community Participation and Review Committee (CPRC) to argue that the Habermasian ideals framing the CPRC are flawed. Habermasian communicative ethics centre upon the notion that fair, free and open forms of debate and communication ensure that no one form of reasoning and/or knowledge dominates others, and so commonly frame attempts to facilitate public participation in technical decision-making. However, in practice, Habermas' advocacy of 'the power of the better argument' (1984) supports adversarial debate and favours conventionally validated (i.e. scientific) forms of knowledge over others. This article identifies this departure from the vision underpinning communicative ethics with the routine deployment of a flawed conception of knowledge. This view - that knowledge is representational in character (that is, in effect, a 'mirror' onto the world) - marginalises lay contributions by rendering them of secondary status (i.e. that they are 'values'); diminishes them by insisting that they take conventional 'expert like' representational form; and supports 'deficit model' approaches (the belief that public antipathy results from knowledge 'deficits' resolvable by expert mediated enhancements in technical literacy). A non-representational epistemology is used to argue that effective participation must rather account for how knowledge is constructed by and through processes, including those of participation/deliberation, rather than existing autonomously of them. The implications of this emphasis on processes, rather than on the sources of and formal characteristics of knowledge, are examined both for public participation and for the dynamics of late-modernity more generally. 相似文献
44.
F. Dale Parent Stephen B. Lovejoy 《Journal of the American Water Resources Association》1982,18(4):593-597
ABSTRACT: Concern over the pollution of our lakes and streams has become a major issue in the United States. Sedimentation from sigricultural lands has been identified as a significant factor in water pollution. Some citizens suggest that government should force compliance with soil loss standards, while others suggest that we ask farmers to voluntarily comply. Related questions are “DO farmers think government should be involved in controlling erosion and protecting water quality?”“To what extent should government be involved?” What level of government should be involved? Federal? State? Local?“Why should pay for water quality projects?” Farmers from a small watershed in northeastern Indiana were interviewed before and after a major demonstration project. Their responses suggest that farmers feel that individual landowners should be responsible for controlling erosion and agricultural nonpoint source water pollution. However, over 60 percent of the study fanners indicated that the federal government should play an important role, in terms of both technical and financial assistance. 相似文献
45.
Peter Wathern Stephen N. Young Ian W. Brown Dawn A. Roberts 《Environmental management》1987,11(1):7-12
The EEC Shellfish Directive is a policy designed to protect and, where necessary, improve the quality of designated shellfish waters. Its implementation within the UK, however, has had no effect upon water quality for two reasons. First, the policy has important defects, having ambiguities concerning public health provisions and lacking designation criteria. Second, UK government has sought to achieve formal compliance, while at the same time ensuring that its full financial impact on public expenditure has been contained. Consequently, only those fisheries which already comply with water quality standards have been designated. Within Wales, one fishery has been designated, while other, commercially more important, but grossly contaminated shellfisheries have not. 相似文献
46.
Expansion of the distribution of exotic rainbow trout is thought to be a leading cause for the decline of native brook trout since the 1930s in Great Smoky Mountains National Park, USA. An experimental rehabilitation project was conducted from 1976 to 1981 using backpack electrofish shockers on four remnant brook trout populations sympatric with rainbow trout. The objectives were to evaluate the effectiveness of the technique to remove the exotic rainbow trout, to determine the population responses by native brook trout, and to evaluate the usefulness of the technique for trout management in the park.Rainbow trout populations were greatly reduced in density after up to six years of electrofishing, but were not eradicated. Rainbow trout recruitment, however, was essentially eliminated. Brook trout populations responded by increasing in density (including young-of-the-year), but rates of recovery differed among streams. The maximum observed densities ir each stream occurred at the end of the project.The findings suggest that electrofishing had a major negative impact on the exotic species, which was followed by positive responses from the native species in the second and third order study streams. The technique would probably be less effective in larger (fourth-order) park streams, but as an eradication tool the technique may have its highest potential in small first order streams. Nonetheless, the technique appears useful for population control without causing undue impacts on native aquatic species, although it is labor intensive, and capture efficiency is greatly influenced by fish size and stream morphology. To completely remove the exotic fish from selected streams, different technologies will have to be explored and developed. 相似文献
47.
Stephen J. Kalkhoff 《Journal of the American Water Resources Association》1995,31(4):593-604
ABSTRACT: An investigation to determine the relation between stream water quality and geohydrology in the Roberts Creek watershed, Clayton County, Iowa, was conducted during selected base-flow periods in 1988–90. Discharge measurements were made and water samples collected for analyses of nutrients and selected herbicides in 19 subbasins along the main stem and tributaries of Roberts Creek. The areal extent of unconsolidated and bedrock units subcropping in each subbasin was quantified. The hydrologic data were correlated statistically with the geologic data to determine relations. Roberts Creek generally gained water and had larger nitrogen concentrations in subbasins in which bess and alluvial material were underlain primarily by low-permeability till and shale units. Roberts Creek generally lost water and had lower nitrate concentrations in subbasins with subcroppmg karstic units. Nitrogen concentrations decreased in streams underlain by the karstic units because the nitrogen removed by biological processes was not replaced by ground-water inflow. Seepage from Roberts Creek to ground water in areas of subcropping karstic carbonate rocks reduced the flow, which reduced the velocity, causing increased residence time of water in the stream. The additional residence time may allow additional time for biological processes to remove nitrogen from solution. There was no significant relation between dissolved orthophosphate or atrazine and the underlying geology. 相似文献
48.
She-Kong Chong Stephen M. Moore 《Journal of the American Water Resources Association》1983,19(2):277-282
ABSTRACT: Twenty-two gaging stations were selected for developing a regional flood frequency curve for small (area less than 2 square miles) watersheds in southern Illinois. Five probability functions were compared, and the extreme value type I function was selected to develop the regional flood curve. The curve was generated with the index flood method and also another empirical method that related the function parameters to the watershed area. Estimated peak discharges with various return periods were compared with the results obtained from multiple regression analysis. 相似文献
49.
Climatic and stream-flow controls on tree growth in a Western montane riparian forest 总被引:2,自引:0,他引:2
Humans have severely impacted riparian ecosystems through water diversions, impoundments, and consumptive uses. Effective
management of these important areas is becoming an increasingly high priority of land managers, particularly as municipal,
industrial, and recreational demands for water increase. We examined radial tree growth of four riparian tree species (Pinus jeffreyi, Populus trichocarpa, Betula occidentalis, and Pinus monophylla) along Bishop Creek, California, and developed models relating basal area increment (BAI) and relative basal area increment
(RBAI) to climatic and stream flow variables. Between years 1995–1999, univariate regression analysis with stream flow explained
29 to 61% of the variation in BAI and RBAI among all species except P. trichocarpa; growth by P. trichocarpa was not significantly related to stream flows over this period. Stepwise linear regression indicated that species responded
differently to climatic variables, and models based on these variables explained between 33 to 86% of variation in BAI and
RBAI during the decade of the 1990s. We examined branch growth of P. trichocarpa for sensitivity to differences in stream flow regimes and found that annual branch growth did not vary between a high- and
low-flow site, but that annual branch growth was significantly higher in wet years with greater stream flows. Our results
support the establishment of site-specific management goals by land managers that take into account all of the important tree
species present in riparian ecosystems and their differential responses to altered hydrologic condition. Instream flow requirements
for maintaining tree growth and vigor are only one of the species-specific responses that need to be evaluated, and these
assessments should attempt to separate experimentally stream-flow (managed) controls from climatic (unmanaged) controls on
growth. 相似文献
50.
This study develops and tests a leadership model that focuses on managers' motivation for attempting the leadership of change. The construct of leadership self‐efficacy (LSE) is defined, and a measure comprising three dimensions (direction‐setting, gaining followers' commitment, and overcoming obstacles to change) is developed. Based on Bandura's (1986) social cognitive theory, the primary hypothesis is that high LSE managers will be seen by direct reports as engaging in more leadership attempts. Relationships are also proposed between LSE and several factors that are expected to influence this confidence judgment. Managers' organizational commitment and crisis perceptions are modelled as potential moderators of the relationship between LSE and leadership attempts. The model was tested through surveys distributed to managers (n = 150) and their direct reports (n = 415) in a real estate management company and an industrial chemicals firm. Positive relationships (p < 0.05) were found between the first two dimensions of LSE and managers' leadership attempts. An interaction effect involving organizational commitment was discovered for the LSE/overcoming obstacles dimension (p < 0.05). Several positive relationships were found between LSE dimensions and proposed antecedents, including self‐esteem (p < 0.05), subordinates' performance abilities (p < 0.05), and managers' job autonomy (p < 0.05). Copyright © 2002 John Wiley & Sons, Ltd. 相似文献