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森林资源的消长与社会经济发展密切相关,而林业的兴衰又直接关系到国民经济和社会的发展。当前,世界林业面临的“四大危机”大部分又是与热带林的破坏密切相关的。因此,研究热带林发展战略是研究当前世界林业的核心问题。本文根据国际组织和各国的大量文献着重就世界热带林的经营管理和发展战略等问题进行了论述。 相似文献
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热带森林森林在许多国家的经济发展以及全球环境保护中发挥着十分重要的作用。国际社会关于森林和环境保护的焦点最初集中在热带林的毁林问题上，并于８０年代中期先后创立了两个国际性的政府间协作计划，即热带林业行动计划和国际热带木材协定１９８３。热带林业行动计划... 相似文献
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作者分析了当前世界林业发展趋势和普遍关注的问题,结合中国林业面临的主要矛盾,提出了今后林业发展对策:1.解决林业的认识问题,摆正林业在国民经济中的位置;2.林业政策要长期稳定,制定有利于发展林业的一系列经济扶持改策;3.要制定全国林业发展的战略规划;4.加强以法治林;5.把林业科研、教育当作战略重点来抓;6.逐步完善和加强林业产业的宏观管理体系;7.加强国际间的经济、技术合作与交流工作。 相似文献
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国家林业局退耕还林赴美培训团 《中国林业》2003,(3)
美国是世界经济强国，也是林业发达国家。美国和世界其他许多发达国家一样，同样经历了毁林开荒、毁林兴牧的历史。随着人们对生态环境的日益重视，为了增加森林面积，美国联邦政府鼓励退耕还林，采取了有力的政策措施，并较好解决了资源开发与利用的矛盾以及实现林业可持续发展等重大问题。一、美国林业概况美国的林业资源比较丰富。北有阿拉斯加的寒带林，大陆本土有广阔的温带林，在波多黎各和夏威夷还有繁茂的热带雨林。全国国土面积为９．３６亿公顷，森林和草地的面积为６．５亿公顷，其中森林面积约３亿公顷。森林覆盖率约为３３％。… 相似文献
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作者分析了当前世界林业发展趋势和普遍关注的问题,结合中国林业面临的主要矛盾,提出了今后林业发展对策:1.解决林业的认识问题,摆正林业在国民经济中的位置;2.林业政策要长期稳定,制定有利于发展林业的一系列经济扶持改策;3.要制定全国林业发展的战略规划;4.加强以法治林;5.把林业科研、教育当作战略重点来抓;6.逐步完善和加强林业产业的宏观管理体系;7.加强国际间的经济、技术合作与交流工作。 相似文献
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综述了目前热带森林资源的现状和变化，分析了热带毁林的成因，并根据国家重点野外科学观测试验——海南尖峰岭热带林生态系统定位研究站及其他热带地区的研究成果，从热带毁林的角度探讨了热带森林生态系统的生态环境保护功能。热带毁林不仅导致林地蓄水、调洪补枯、保护森林生态系统的营养循环、调节气候等生态功能失效，而且对生物多样性保护、大气温室气体含量增加等全球性的生态环境问题产生巨大的影响，说明了保护热带森林的重要性。 相似文献
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文章介绍了德意志帝国乃至联邦德国的森林利用史,林业的起源,各个历史时期的管理政策以及林业发展过程中的经验教训。作者据此认为,联邦德国林业发展道路是:农业毁林、工业毁林、工业扶林和农地还林。 相似文献
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森林认证的现状与发展趋势 总被引：17，自引：3，他引：14
森林认证出现于20世纪90年代初,10年来,森林认证在全球范围内取得了快速的发展。文中介绍了森林认证的起源和发展现状,指出了森林认证的发展趋势,并对我国开展森林认证提出了建议。 相似文献
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印度是个千年古国,在发展林业方面有着独到之处。几百年来印度林业经历了森林破坏阶段、巩固和保护阶段、开发和扩大阶段、集约经营阶段和生态林业阶段。作者对于印度发展社会林业、森林发展公司,以及缓解薪炭材危机所采取的对策作了重点介绍,同时还指出了存在的问题和采取的措施。 相似文献
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Jochen Schngart 《Forest Ecology and Management》2008,256(1-2):46-58
Against a background of increasing human populations in developing countries, and global climate change, conservation of tropical forests remains one of the most important ecological challenges of our time. One of the biggest difficulties for ecologically sustainable management of tropical forests is obtaining reliable growth data for trees, which is a prerequisite for determining harvesting volumes and cutting cycles. GOL is the first concept for sustainable management of tropical timber resources in Amazonian floodplain forests (várzea) based on species-specific management criteria, such as minimum logging diameters (MLDs) and cutting cycles. From timber species with varying wood densities of different successional stages, volume stocks have been estimated in 1-ha plots and 12 growth models have been developed based on tree rings, which are annually formed as a consequence of the regular, long-term flooding. The MLDs of timber species vary between 47 and 70 cm and the estimated cutting cycles differ the 10-fold, from 3 to 32 years. These enormous differences in the growth rates between tropical timber species are not considered in current management practices, which apply only one diameter cutting limit and one cutting cycle to harvest many tree species. This practice risks the overexploitation of slow-growing timber species, while the fast-growing timber species with low wood densities cannot be efficiently used. Based on the timber stocks and lifetime growth rates, the GOL concept has been created as an aid to improve forest management in the Central Amazonian várzea. The model is unique for tropical silviculture. 相似文献
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Biodiversity loss is a major problem in terms of loss of genetic and ecosystem services and more specifically via impacts on the livelihoods, food security and health of the poor. This study modeled forest management strategies that balance economic gains and biodiversity conservation benefits in planted tropical forests. A forest-level model was developed that maximized the net present value (NPV) from selling timber and carbon sequestration while maintaining a given level of biodiversity (as per the population density of birds). The model was applied to Eucalyptus urophylla planted forests in Yen Bai Province, Vietnam. It was found that the inclusion of biodiversity conservation in the model induces a longer optimal rotation age compared to the period that maximizes the joint value from timber and carbon sequestration (from 8 to 10.9 years). The average NPV when considering timber values plus carbon sequestration was 13 million Vietnamese Dong (VND) ha− 1 (765 USD ha− 1), and timber, carbon sequestration and biodiversity values were 11 million VND (676 USD) ha− 1. Given this differential, governments in such tropical countries may need to consider additional incentives to forest owners if they are to encourage maximizing biodiversity and its associated benefits. The results also have some implications for implementing the climate control measure of “Reducing Emissions from Deforestation and Forest Degradation-plus (REDD +)” in developing countries, i.e., payment for carbon sequestration and biodiversity benefits in planted forests. 相似文献
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Norman Myers 《Forest Ecology and Management》1983,6(1):59-79
Tropical moist forests (TMFs) are undergoing three principal types of exploitation — commercial logging, large-scale ranching and small-scale cultivation — that generally amount to unsustainable use. These modes of exploitation, or rather over-exploitation, focus on only a very few of the many products available from the forest ecosystems, resulting in degradation if not destruction for the rest. Through systematic screening of raw materials such as phytochemicals and genetic resources for industry, agriculture, and medicine, we could make expanded use of tropical forests — and the harvesting of these low-volume products need cause little disruption of forest ecosystems. Moreover, tropical forests offer many environmental services, whose value is increasingly apparent as deforestation proceeds. A comprehensive development strategy is required if we are to make best use of these forests, with a shift in emphasis from short-term, narrow-interest exploitation of a few products, to long-term, broad-scale utilization of whatever goods and services can be made available without degradation of the ecosystem. 相似文献
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世界毁林趋势及其原因和后果 总被引：1，自引：0，他引：1
全球森林每年消毁达1100万公顷,主要是发展中国家的热带森林,温带森林变化不大,有些国家还有所增加。但面临着酸雨的危害,造成部分地区森林片状衰亡。森林消毁的原因是:(1)滥伐而不更新;(2)砍伐森林转为农业用地或牧场;(3)砍伐大量燃料用材。森林大幅度消减后所带来的后果;(1)影响气候变化,使全球性水文循环失调,改变了大气的组成,增加大气中二氧化碳含量,造成增温;(2)加剧水源区土壤侵蚀,造成河流下游泥沙淤积;(3)不少动植物物种濒临灭绝。 相似文献
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菲律宾“国家造林计划”是世界十大重点生态工程之一。为了遏制森林破坏，恢复退化的热带林和红树林，改善生态状况，提供就业机会，促进乡村发展，菲律宾于1987年启动“国家造林计划（NFP）”。该计划到2010年完成造林202.6万hm2。为加大生态建设力度，2011年又开展了二期的“国家绿化计划（NGP）”（2011—2022年），计划造林270万hm2，而2011—2020年实际完成造林200多万hm2。“国家造林计划”和随后的“国家绿化计划”总目标为造林510万hm2（去除重叠部分），到2020年底实际完成造林410万hm2。在计划实施中，采取了促进人工造林、加强社区森林管理、坚持高层推动、完善规划和政策等多项措施，在生态、经济和社会方面都取得了良好成效。菲律宾“国家造林计划”对我国的主要政策启示包括谋划新的工程、实行依法治理、坚持共建共享、强化科技支撑、重视宣传发动。 相似文献
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Portugal's forests in the 12th century were dominated by the Fagaceae represented by Quercus and Castanea, and several pine species.From the 12th century onwards, forests underwent changes in their management starting with protection and ultimately leading to intense exploitation. The massive naval construction during the maritime expansion(mainly in the 15th–16th centuries) involved felling of approximately 5 million trees mainly Quercus suber, Pinus pinea and other Quercus species. Cumulative fuel-wood consumption of 959 Mm3 during 1300–1854 was attributed to demographic expansion while the deforestation rate during 1636–1854 accounted for a minimum of 72.6% and a maximum of 96% of total forest cover. The volume of timber used in railway sleepers from 1856 onwards might have reached 0.5 Mm3. The last quarter of the 20th century increased the forest cover of Portugal through the World Bank program of Eucalyptus globulus reforestation. 相似文献