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This paper examines the relationship between North American beef consumption and deforestation in South and Central America.
Some writers have argued that consumption of hamburgers in North America, particularly hamburgers consumed in fast food restaurants,
contributes to the depletion of the rainforest in South and Central America. We survey the published policy literature on
the causes of rainforest depletion in the region. We also review the published estimates of the rate and extent of clearing
of rainforest that has occurred in South and Central America since 1970. Finally, we review the data on beef imports and consumption
in Canada and the United States in a effort to assess the importance of South and Central America as suppliers of beef to
the North American market. We conclude that the relationship between beef consumption in North America should not be considered
an important cause of forest depletion in South and Central America. Domestic policies and market forces in the countries
where rainforests are located are the leading causes of rainforest depletion in this region. This lesson seems to have been
lost on some popular and even some textbook writers on this subject.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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W.I. Ford J.F. Fox D.T. Mahoney G. DeGraves A. Erhardt S. Yost 《Journal of the American Water Resources Association》2020,56(4):692-711
In the Ohio River (OR), backwater confluence sedimentation dynamics are understudied, however, these river features are expected to be influential on the system’s ecological and economic function when integrated along the river’s length. In the following paper, we test the efficacy of organic and inorganic tracers for sediment fingerprinting in backwater confluences; we use fingerprinting results to evidence sediment dynamics controlling deposition patterns in confluences used for wetland and marina functions; and we quantify the spatial extent of tributary drainages with wetland and marina features in OR confluences. Both organic and inorganic tracers statistically differentiate sediment from stream and river end‐members. Carbon and nitrogen stable isotopes produce greater uncertainty in fingerprinting results than inorganic elemental tracers. Uncertainty analysis of the nonconservative tracer term in the organic matter fingerprinting application estimates an apparent enrichment of the carbon stable isotopes during instream residence, and the nonconservativeness is quantified with a statistical approach unique to the fingerprinting literature. Wetland and marina features in OR confluences impact 42% and 11% of tributary drainage areas, respectively. Sediment dynamics show wetland and marina confluences experience deposition from river backwaters with longitudinally linear and nonlinear patterns, respectively, from sediment sources. 相似文献
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Increasing abundance of geese in North America and Europe constitutes a major conservation success, but has caused increasing conflicts with economic, health and safety interests, as well as ecosystem impacts. Potential conflict resolution through a single, ‘one size fits all’ policy is hindered by differences in species’ ecology, behaviour, abundance and population status, and in contrasting political and socio-economic environments across the flyways. Effective goose management requires coordinated application of a suite of tools from the local level to strategic flyway management actions. The European Goose Management Platform, established under the Agreement on the Conservation of African-Eurasian Migratory Waterbirds, aims to harmonise and prioritise management, monitoring and conservation efforts, sharing best practice internationally by facilitating agreed policies, coordinating flyway efforts, and sharing and exchanging experiences and information. This depends crucially upon adequate government financing, the collection of necessary monitoring data (e.g., on distribution, abundance, hunting bags, demography, ecosystem and agricultural damage), the collation and effective use of such data and information, as well as the evaluation of outcomes of existing management measures. 相似文献
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Simulating Land-Cover Change in Montane Mainland Southeast Asia 总被引:6,自引:0,他引:6
We used the conversion of land use and its effects (CLUE-s) model to simulate scenarios of land-cover change in Montane mainland
southeast Asia (MMSEA), a region in the midst of transformation due to rapid intensification of agriculture and expansion
of regional trade markets. Simulated changes affected approximately 10 % of the MMSEA landscape between 2001 and 2025 and
16 % between 2001 and 2050. Roughly 9 % of the current vegetation, which consists of native species of trees, shrubs, and
grasses, is projected to be replaced by tree plantations, tea, and other evergreen shrubs during the 50 years period. Importantly,
4 % of this transition is expected to be due to the expansion of rubber (Hevea brasiliensis), a tree plantation crop that may have important implications for local-to-regional scale hydrology because of its potentially
high water consumption in the dry season. 相似文献
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Fourteen streams in the Sierra Nevada in the USA were sampled to determine whether diversions of streamflow for hydroelectric development had caused significant changes in riparian vegetation. Several streams showed significant differences in vegetation cover, community composition, or community structure between pairs of diverted and undiverted reaches. On some streams, environmental conditions rather than streamflow diversions may have been responsible for vegetation differences. Streams in the Sierra Nevada respond individualistically to diversions. Prediction of vegetation responses must take into consideration environmental characteristics of specific stream reaches. 相似文献
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Inconsistent findings have been reported in the few studies investigating the relationship between the perceived value of pay and incentive performance. One hundred and seventy-eight female incentive employees with a nine-week, non-judgmental performance measure responded to a developed valence of pay scale. This measure used items assessing the perceived ability of pay to address employee needs. Three factor-scales were found within these items. Support for the hypothesized positive relationship between pay valence and incentive performance was found, dependent on which of the three scales was used. These findings provide initial insight into the means by which pay, with its ability to address different needs, might provide differential employee motivation and performance levels. This study and future research issues are discussed. 相似文献
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