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41.
This paper examines the potential role of forest set-asides in global carbon sequestration policy. While set asides that protect
forests from timber harvests and land-use conversion may alleviate concerns with permanence, and they may provide large ancillary
environmental benefits, they may also lead to large leakage. This paper uses a global land use and forestry model to examine
the efficiency of three crediting schemes for set-asides. The results show that if set-asides are integrated into a global
forestry carbon sequestration program that includes a wide range of other management options, then 300 million hectares of
land would be set-aside, and up to 128 Pg C could be sequestered in global forests by 2105. Under alternative policies that
focus exclusively on set-asides, more forestland can be set-asides, up to 3.2 billion hectare, but these policies invite large
leakage in the near-term, and in the long-run, they less net carbon is removed from the atmosphere. Specifically, leakage
is estimated to be 47–52%, depending on the policy, and by the end of the century, up to 17% less carbon will be sequestered
in all forests. 相似文献
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The co-production of land use and livelihoods change: Implications for development interventions 总被引:1,自引:0,他引:1
In a previous paper [McCusker, B., Carr, E.R., 2006. The co-production of livelihoods and land use change: Case studies from South Africa and Ghana. Geoforum 37 (5), 790–804], we argued that land use and livelihoods could best be understood as co-produced, where land use and livelihoods are not separate objects of knowledge related to one another through abstract processes, but different manifestations of social processes through which individuals and groups come to understand the challenges facing their everyday lives, the various resources available to them to negotiate these challenges, and the strategies by which they can conduct that negotiation. In this paper, we examine the theoretical basis for “co-production” with the goal of using this approach to inform development interventions. 相似文献
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通过对岩浆冷却过程的数字模拟研究,揭示出岩浆在冷却成矿过程中的温度分布和变化规律及影响因素.在此基础上,进一步应用高精度的温龄计组合来限定岩浆成矿体系的热演化和剥露历史,精确地计算出岩浆的初始侵位时间和深度、矿物结晶时间、冷却速率、冷却和暴露地表时间,以及剥露和剥蚀速率等重要参数,并将模拟结果应用于斑岩铜矿床的成矿研究中.研究表明,将精确的年龄测试手段与计算机模拟技术相结合,可为定量研究岩浆矿床的热演化和剥露史、深入了解矿床的成因机制提供一种有效方法. 相似文献
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Natural Hazards - Informing and warning beach users about the danger posed by the rip current hazard remain a difficult challenge. Recent evidence suggests that warning signs and flags alone have... 相似文献
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Recent studies have suggested that poikilothermic animals, such as fish, may represent a previously overlooked source of the faecal indicator bacteria (FIB) used for the assessment of water quality. However, quantitative studies of FIB in poikilotherms are scarce. We investigated the presence of FIB in the faeces of five freshwater fish species. E. coli and enterococci were detected in 71 and 76% of faecal samples, respectively. Concentrations were highly variable, with maximum concentrations (2.1?×?104 E. coli and 1.3?×?106 enterococci per gram of faecal material) up to four orders of magnitude higher than present in the water column. FIB were not detected in faecal samples from marine fish. Our findings suggest that FIB ingested from the environment may be capable of replication within the fish gut, making fish a potential source and transport mechanism for FIB in New Zealand freshwaters. This may have implications for water quality monitoring. 相似文献
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Adam C. Landon Maarten H. Jacobs Craig A. Miller Jerry J. Vaske Brent D. Williams 《社会与自然资源》2020,33(5):574-593
AbstractIncreasing wolf populations are a concern for wildlife managers in the Midwestern U.S. Understanding the psychological mechanisms that contribute to public perceptions of risk will enable development of strategies that seek to mitigate these risks, and suggest where outreach efforts may facilitate acceptance of wolves. We examined the psychological factors that influence Illinois residents’ perceived risks from wolves. We hypothesized that individuals’ perceived risks from wolves were a function of their attitudes toward wolves, negative affect toward wolves, and basic beliefs about wildlife. Data were obtained from a survey of the Illinois public (n?=?784). Negative affect and attitudes toward wolves were direct predictors of perceived risks. Basic beliefs predicted attitudes and negative affect toward wolves. Negative affect predicted attitudes. Basic beliefs had direct and indirect effects on perceived risks. 相似文献
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