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481.
Palmer JF 《Journal of environmental management》2008,89(3):167-183
The scenic effects of clearcutting have been a volatile issue for the American public for much of the past century. A better understanding of the scenic perceptions associated with the cumulative visible effects of clearcutting should contribute to better decisions about its use. This study evaluates the scenic impacts of simulated alternative clearcutting management systems for the White Mountain National Forest. Alternatives represented an unharvested view, and views with removal of 1–5% of the timber every 12 years using either scattered or concentrated clearcut units of 5, 15 and 30 acres in two viewsheds. A random sample of local citizens, four groups of opinion leaders, and US Forest Service employees evaluated these alternatives. Each factor accounts for significant differences in scenic value. All groups rated the scenic value of unharvested scenes very high. All groups find a large drop in scenic value with the introduction of even the least intense harvesting activity. All groups indicated a statistically significant decrease in visual quality as the intensity of harvesting increases. This effect continues throughout the range of harvesting intensities until the level of sustainable yield is reached. In addition, patches 12–15 acres in size were preferred to larger and smaller ones. 相似文献
482.
The article considers the impact of introducing government co-management policy in the form of Joint Forest Management (JFM) in an area with a five-decade-old self-organized community forest management system in Orissa, India. We ask a question that appears not to have been previously examined: What happens when JFM replaces an already existing community forest management arrangement? Our comparison of the JFM arrangement with the self-organized community forest management regime (pre- and post-2002 in a selected village) provides three conclusions: (1) The level of villager participation in forest management has declined, along with the erosion of the bundle of common rights held by them; (2) multiple institutional linkages between the village and outside agencies, and reciprocal relations with neighboring villages have been abandoned in favor of a close relationship with the Forestry Department; and (3) the administration of the forestry resource has become politicized. We conclude that the “one-size-fits-all” approach of the JFM, with its pre-packaged objectives and its narrow scope of forest management, is likely to limit experimentation, learning, and institutional innovation that characterizes community forest management. 相似文献
483.
淡竹森林公园地处括苍山脉中部,保存有括苍山脉最好、最完整的常绿阔叶林,是浙中和浙东沿海区域原生性最强的原始次生森林。在系统调查的基础上,分析得出淡竹森林公园旅游资源的6大特点——风景资源品味较高,天然常绿阔叶林景观较典型,水体景观多姿多彩,山体和岩体景观奇妙,森林环境优异,山区风情较淳厚;提出了淡竹森林公园旅游开发的5条基本思路,即依法开发、保护为先,体现特色与周边景区互补相结合,突出重点与循序发展相结合,旅游产品应以自然性休闲型为主导,塑造主题旅游形象,强化宣传促销。 相似文献
484.
Until the 20th century, forest policies across the globe focused primarily on effective forest utilization for timber production. Subsequent loss of forest land prompted many countries to review and amend such policies, in an attempt to incorporate the principles of conservation and sustainable forest management. One of the countries to implement such changes was India, which introduced new policies, acts and programmes to regulate forest conversion and degradation, beginning in the 1980s. These policies, acts, and programmes included the Forest Conservation Act of 1980, the National Forest Policy of 1988 and the Hon. Supreme Court Order of 1996. All of these regulations affected the timber supply from government forest areas, and created a huge gap in timber supply and demand. Currently, this deficit is met through imports and trees outside forests (TOFs). Timber production from government forest areas is abysmally low (3.35% of total demand) compared to potential timber production from TOFs, which fulfil 45% of the total timber demand in India. This implies that TOFs have immense potential in meeting the growing timber demand; however, they have not been fully utilized due to discrepancies in state level TOFs’ policies. The present paper provides a review of different forest policies, acts and guidelines in relation to timber production in India, and provides specific recommendations in order to maximize timber production in the context of increasing demand for timber products. 相似文献
485.
India's forest biodiversity management regime is analysed at the policy, legal and institutional levels, from the perspective of the triple objectives of the Convention on Biological Diversity and the principles of the Indian constitution. The forest biodiversity management regime has both structural and functional flaws that render it largely incapable of facing the challenge of increasing biodiversity degradation and deepening poverty among the Adivasis and other forest‐dependent communities. The paper argues for the reform of the forest biodiversity management regime and offers recommendations in regard to most aspects of the regime, with a view of putting the country's conservation enterprise on a course that is effective, sustainable and inclusive, rejecting the report of the High Power Committee (HPC) (also known as the Subramanian Committee), which is premised on easing corporate access to forests. 相似文献
486.
Climate change incurs costs, but government adaptation budgets are limited. Beyond a certain point, individuals must bear
the costs or adapt to new circumstances, creating political-economic tipping points that we explore in three examples. First,
many Alaska Native villages are threatened by erosion, but relocation is expensive. To date, critically threatened villages
have not yet been relocated, suggesting that we may already have reached a political-economic tipping point. Second, forest
fires shape landscape and ecological characteristics in interior Alaska. Climate-driven changes in fire regime require increased
fire-fighting resources to maintain current patterns of vegetation and land use, but these resources appear to be less and
less available, indicating an approaching tipping point. Third, rapid sea level rise, for example from accelerated melting
of the Greenland ice sheet, will create a choice between protection and abandonment for coastal regions throughout the world,
a potential global tipping point comparable to those now faced by Arctic communities. The examples illustrate the basic idea
that if costs of response increase more quickly than available resources, then society has fewer and fewer options as time
passes. 相似文献
487.
Surface water concentrations of dissolved organic carbon ([DOC]) are changing throughout the northern hemisphere due to changes
in climate, land use and acid deposition. However, the relative importance of these drivers is unclear. Here, we use the Integrated
Catchments model for Carbon (INCA-C) to simulate long-term (1996–2008) streamwater [DOC] at the four Swedish integrated monitoring
(IM) sites. These are unmanaged headwater catchments with old-growth forests and no major changes in land use. Daily, seasonal
and long-term variations in streamwater [DOC] driven by runoff, seasonal temperature and atmospheric sulfate (SO4
2−) deposition were observed at all sites. Using INCA-C, it was possible to reproduce observed patterns of variability in streamwater
[DOC] at the four IM sites. Runoff was found to be the main short-term control on [DOC]. Seasonal patterns in [DOC] were controlled
primarily by soil temperature. Measured SO4
2− deposition explained some of the long-term [DOC] variability at all sites. 相似文献
488.
489.
490.
Hyacinth Eme Ichoku William M. Fonta Abbi Kedir 《Environment, Development and Sustainability》2009,11(3):509-521
The objectives of this study are twofold. First it aims to establish empirical grounds for pricing the services of a new environmental
management initiative in Enugu state, Nigeria. A joint initiative of the UK Department for International Development (DfID),
Enugu State Environmental Protection Agency (ENSEPA) and the State and Local Government Programme (SLGP). The second is to
test the empirical performance of a new approach to the contingent valuation method (CVM) i.e., the Stochastic Payment Card
(SPC) design proposed by Wang (Contingent valuation of environmental resources: A stochastic perspective, 1997a, Journal of Environmental Economics & Management, 32:219–232, 1997b). The SPC design unlike many of the conventional CVM elicitation formats, takes into account the stochastic nature of individuals’
valuation decisions. The data for the analysis were obtained from a random sample survey of a district in Enugu metropolis.
The results show that, on average, households in this city are willing to pay (WTP) 215 Naira ($1.6) monthly as against 200 Naira
($1.5) currently charged for the service by ENSEPA. Analysis of individual’s valuation distribution function indicates that
this amount is positively and significantly related to the gender of the respondent, household income and the respondent’s
perception of environmental quality.
相似文献
Abbi KedirEmail: |