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我所认识的美国林务局魏列杰美国农业部林务局是管理美国森林与草地的联邦机构,也是世界上最大的林业研究组织。它向美国国有或私有林业机构提供财政与技术支持。美国林务局第一任局长杰福特·皮查特总结林务局业务时说,林务局“长时期为大多数人民提供最大量的物品”,... 相似文献
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美国是一个地方分权的联邦制国家 ,联邦政府在农业部下设林务局。林务局内部设有行政管理、国会关系与企划、国有林管理、研究与发展、州有林及私有林和国际项目等 6个司。林务局是管理国有林地和公共草场及水域湿地的联邦机构 ,也是世界上最大的林业研究组织 ,为国有和私有林业机构提供技术和经济资助。美国林务局以实现多种用途和利益为目的来管理森林 ,以保证再生资源 (木材生产、牧业生产、野生动物、水资源和娱乐活动 )的持续发展。林务局的工作宗旨是“关爱土地 ,服务人民”,并通过以下 5个方面的工作来实现 :(1)保护和管理国有林区的… 相似文献
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在美国,森林的所有制形式有国有、州有及私有等多种形式。国有林出现在100多年以前。目前,国有森林主要由林务局和国土资源部两个部门管理,而其中绝大部分由林务局管理。 相似文献
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根据美国林务局1992年森林资源数据更新汇总等有关材料,介绍了美国森林资源总量,以及按各类面积、蓄积、权属的分配情况,指出了用美国的森林资源与我国森林资源相比时应注意的问题。介绍了美国的森林资源调查方法、调查成本、机构和调查历史以及美国林务局负责森林调查的主要机构—FIA近十年5个方面的主要工作和研究项目。 相似文献
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韦面勤 《云南林业调查规划设计》1999,24(1):51-53,50
根据美国林务局1992年森林资源数据更汇总等有关材料,介绍了美国森林资源总量,以及按各类面积、蓄积、权属的分配情况,指出了用美国的森林资源与我国森林资源相比时应注意的问题,介绍了的森林资源调查方法,调查成本、机构和调查历史以及美国林务局负丽森林调查的主要机构-FIA近十年5个方面的主要工作和研究项目。 相似文献
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Dry forests across the United States have become subject to declining resilience and, consequently, increased vulnerability to catastrophic wildfires. These disturbances cause severe environmental and social damages and may dislodge the forest into a different ecological regime. Forests provide many valuable services, such as the provisioning of timber and the sequestering of carbon that would otherwise contribute to climate change. The high-severity conflagrations that have become regular occurrences in many dry forests impinge the delivery of such benefits, particularly in the event of a regime shift. Sustainable forest management should take these risks into account. This article analyzes the economics of resilience in dry forests with respect to catastrophic fires and ecological thresholds. We illustrate how to price ecosystem resilience for the fire-prone ponderosa pine forests of the western United States. This analysis demonstrates that pricing forest resilience also establishes the economic value of ecological restoration with respect to ecosystem services, thereby operationalizing forest management as an investment in natural capital. 相似文献
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《Forest Ecosystems》2015,(4)
Background:With the loss of species worldwide due to anthropogenic factors,especially in forested ecosystems,it has become more urgent than ever to understand the biodiversity-ecosystem functioning relationship(BEFR).BEFR research in forested ecosystems is very limited and thus studies that incorporate greater geographic coverage and structural complexity are needed.Methods:We compiled ground-measured data from approx.one half mil ion forest inventory sample plots across the contiguous United States,Alaska,and northeastern China to map tree species richness,forest stocking,and productivity at a continental scale.Based on these data,we investigated the relationship between forest productivity and tree species diversity,using a multiple regression analysis and a non-parametric approach to account for spatial autocorrelation.Results:In general,forests in the eastern United States consisted of more tree species than any other regions in the country.The highest forest stocking values over the entire study area were concentrated in the western United States and Central Appalachia.Overall,96.4 % of sample plots(477,281)showed a significant positive effect of species richness on site productivity,and only 3.6 %(17,349)had an insignificant or negative effect.Conclusions:The large number of ground-measured plots,as well as the magnitude of geographic scale,rendered overwhelming evidence in support of a positive BEFR.This empirical evidence provides insights to forest management and biological conservation across different types of forested ecosystems.Forest timber productivity may be impaired by the loss of species in forests,and biological conservation,due to its potential benefits on maintaining species richness and productivity,can have profound impacts on the functioning and services of forested ecosystems. 相似文献
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Andrew Youngblood 《Forest Ecology and Management》2011,261(5):937-947
The United States Department of Agriculture (USDA) Forest Service celebrated the 100th anniversary of its network of experimental forests in 2008. For a century, the network of experimental forests have contributed immensely—both in the US and around the world—to the practical understanding of the environment and to the formation of management approaches and policies that affect our use of forests and the natural resources they contain. Experimental forests provide places for long-term science and management studies in major vegetation types across the 789,140 km2 of public land administered by the Forest Service. They also provide an incredible wealth of records and knowledge of environmental change in natural and managed forest ecosystems across the United States. Pringle Falls Experimental Forest (Pringle Falls), southwest of Bend, Oregon, is the oldest experimental forest in the Pacific Northwest and is the site of some of the earliest forest management and silviculture research in this region. Research at this site began in 1914, and it was formally established as part of the national network of experimental forests in 1931 as a center for silviculture, forest management, and insect and disease research in ponderosa pine forests east of the Oregon Cascade Range. As part of the celebration of the Centennial Anniversary of the network of experimental forests, it is timely to examine a few of the ecological lessons that have resulted from long-term studies at Pringle Falls. Two different yet interconnected themes are traced: (1) management of existing old-growth ponderosa pine; and (2) management of young or immature ponderosa pine. Examples of ecological lessons, drawn from long-term studies established or followed by James W. Barrett, Matt D. Busse, Patrick H. Cochran, Walter G. Dahms, F. Paul Keen, Ernest L. Kolbe, Edwin L. Mowat, William W. Oliver, Ram Oren, Chester T. Youngberg, and Jianwei Zhang illustrate how work at Pringle Falls has both pursued and influenced societal demands for forest management strategies, and how this trajectory has cycled back to the themes under which the experimental forest was first established. Finally, these two themes are integrated as drivers for new landscape-scale long-term research at Pringle Falls, designed to evaluate the effects of thinning and fuel reduction treatments on multiple, interacting forest stresses of fire, insects, wind, and climate change. 相似文献
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森林景观设计研究综述 总被引:2,自引:1,他引:1
合理的森林景观设计可以使森林同时发挥经济、社会和生态效益。文中介绍了各种流派的森林景观设计定义及体系, 如英国主动设计途径、美国视觉管理系统、加拿大不列颠哥伦比亚设计途径的理论和方法等; 系统阐述了英国主动设计途径与美国视觉管理系统2种主要设计途径在西班牙和爱尔兰的应用; 结合我国的审美理念, 提出了建立有中国特色的森林景观设计体系的建议。 相似文献