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1.
The National Forest Management Act (NFMA) requires the Forest Service to provide for diversity of plant and animal communities and maintain viable wildlife populations. Changes in forest stand structure, species composition and disturbance patterns within ponderosa pine (Pinus ponderosa)-Douglas-fir (Pseudotsuga menziesii) habitat types on the Boise National Forest make it difficult to meet NFMA direction. Three management strategies, including "no action," were evaluated in terms of the risk of wildfire's effects on plant community diversity and distrbution, dispersal, and local population viability for the pileated woodpecker (Dryocopus pileatus) and flammulated owl (Otus flammeolus). The no action alternative appeared to have the greatest long-term risk to plant community diversity and wildlife species distribution and dispersal. Landscape analysis that considers the capabilities and risks associated with different-management strategies is recommended to meet NFMA direction while responding to diverse public expectations of the Forest.  相似文献   

2.
文章回顾了美国国有林的发展历程,并介绍了一些重大历史事件。作者着重阐明了美国国有林的管理体制和技术经济政策。  相似文献   

3.
During the 1980s and early 1990s, the New Zealand economy went through radical economic changes, overhauling almost all aspects of economic policy. The New Zealand Forest Service was not exempt from these changes. This paper describes two major aspects of that change: the way the New Zealand Forest Service, like many other state trading activities, was restructured first through corporatisation under the State-Owned Enterprises Act 1986 which has ultimately led to privatisation; and secondly through the enactment of the New Zealand Resource Management Act 1991 which has fundamentally altered environmental management in New Zealand. The Act's underlying principle is based on the principle of sustainable management. This principle forms the foundation of forest management in New Zealand. Whether the restructuring and privatisation will produce a more efficient forestry sector is an issue that the author does not address. The Crown Assets sales are an ongoing and dynamic process which still have not been completed. This is a shortened version of a chapter originally presented in her LL.M. Thesis in 1995.  相似文献   

4.
The National Environmental Policy Act (NEPA) of 1970 changed the landscape of natural resource management by requiring federal agencies to assess the environmental consequences of their proposed actions and to include the public in their decision-making processes. Of all federal agencies in the United States, the Forest Service prepares the most Environmental Impact Statements under NEPA. The U.S. Forest Service manages the National Forest System, public forestlands comprising approximately 9% of the United States land area. The overall objectives of this study were to (1) determine the litigants, success rates, and management activities disputed for NEPA litigation involving the Forest Service from 1970 to 2001 and (2) examine differences and patterns in cases among the U.S. District, Circuit, and Supreme Courts. Methods include a historical analysis of published court cases and results show an increasing trend in the number of NEPA-Forest Service cases in the federal courts. Environmental groups were the most common litigants in NEPA-Forest Service cases and timber harvesting, management plans, and endangered species were the subject of the majority of cases in both the U.S. District Court and the U.S. Circuit Court of Appeals. The Forest Service won a preponderance of cases in which they were involved with success rates of 60% in U.S. District Court, 57% in the U.S. Circuit Court of Appeals, and 100% in the U.S. Supreme Court.  相似文献   

5.
This article demonstrates that the opportunity cost (return forgone) of cutting principles imposed by the Swedish forest policy is economically significant. The Swedish Forestry Act of 1979 recommends a management strategy for sustaining high yields of valuable timber referred to here as the Balance Strategy. However, the Forestry Act allows for a range of different forest management strategies. The Act establishes both a minimum cutting volume for a ten‐year‐period and a maximum final cut area referred to here as the Minimum and Maximum Strategies, respectively. These strategies were compared to a management plan, referred to as the Economic Strategy, for minimizing the opportunity cost for the forest owner. Based on data from a recent forest management plan, a simulation model was used to predict yields and economic returns for a period of one hundred years. The results show that at a 4% interest rate the Economic Strategy produces a gain of approximately 8200 SEK ha‐1. The Economic Strategy, however, emphasizes volume and its implementation results in a forest far different from that developed under the Balance Strategy, in which quality timber is also produced. The Economic Strategy may also have less favourable effects on biodiversity, conservation of the natural environment and the recreational value of the forest.  相似文献   

6.
SANZEN-BAKER  R. G. 《Forestry》1970,43(2):105-123
The Forest of Dean has been an area of outstanding nationaleconomic importance because of its mineral wealth and timberresources. Iron ore had been mined and smelted with the aidof charcoal since the earliest times. Coal-mining subsequentlybecame a major industry in the nineteenth century and coke replacedcharcoal in the ironworks. Exploitation of the timber resourcesof the Forest reached its peak in the middle of the seventeenthcentury. This was accentuated by excessive grazing of sheep,pigs, and other animals. There was national concern for thedisappearing supplies of naval ship-timber. This culminatedin the Dean Forest (Reafforestation) Act of 1668 Forest management had its ups and downs. The Napoleonic Warsmade tremendous demands on the Dean oak and the nineteenth centurysaw a new wave of reafforestation and the tending of oak speciallyfor shipbuilding. Unfortunately the demand for oak ship-timberceased about the middle of the century because of the developmentof iron warships. The twentieth century has not only seen twoworld wars deplete the Forest of its timber but has witnessedthe introduction of planned forest management and the large-scaleuse of conifers, some of which are particularly suited to theDean environment. More than half the woodland is now stockedwith conifers but there have been amenity safeguards and theeffect is not unpleasing.  相似文献   

7.
Restoring altered forest landscapes toward their ranges of natural variability (RNV) may enhance ecosystem sustainability and resiliency, but such efforts can be hampered by complex land ownership and management patterns. We evaluated restoration potential for southern-boreal forests in the ∼2.1 million ha Border Lakes Region of northern Minnesota (U.S.A.) and Ontario (Canada), where spatially distinct timber harvest and fire suppression histories have differentially altered forest conditions (composition, age–class distribution, and landscape structure) among major management areas, effectively resulting in forest landscape “bifurcation.” We used a forest landscape simulation model to evaluate potential for four hypothetical management and two natural disturbance scenarios to restore forest conditions and reduce bifurcation, including: (1) a current management scenario that simulated timber harvest and fire suppression practices among major landowners; (2) three restoration scenarios that simulated combinations of wildland fire use and cross-boundary timber harvest designed to emulate natural disturbance patterns; (3) a historical natural disturbance scenario that simulated pre-EuroAmerican settlement fire regimes and windthrow; and (4) a contemporary fire regime that simulated fire suppression, but no timber harvest. Forest composition and landscape structure for a 200-year model period were compared among scenarios, among major land management regions within scenarios, and to six RNV benchmarks. The current management scenario met only one RNV benchmark and did not move forest composition, age–class distribution, or landscape structures toward the RNV, and it increased forest landscape bifurcation between primarily timber-managed and wilderness areas. The historical natural disturbance scenario met five RNV benchmarks and the restoration scenarios as many as five, by generally restoring forest composition, age–class distributions, and landscape structures, and reducing bifurcation of forest conditions. The contemporary natural disturbance scenario met only one benchmark and generally created a forest landscape dominated by large patches of late-successional, fire-prone forests. Some forest types (e.g., white and red pine) declined in all scenarios, despite simulated restoration strategies. It may not be possible to achieve all objectives under a single management scenario, and complications, such as fire-risk, may limit strategies. However, our model suggests that timber harvest and fire regimes that emulate natural disturbance patterns can move forest landscapes toward the RNV.  相似文献   

8.
9.
本文以南平地区建瓯水西林场的现实森林为研究对象,重点以杉木中径材作为主要材料,根据该场对树种结构的要求和适地适树原则,运用线性规划方法建立该经营类型的森林收获调整模型,并分析了调整期内各分期的面积变化情况。  相似文献   

10.
Forest owners’ cooperatives are one of the leading organizations in the forest sector in Japan. Yusuhara Forest Owners’ Cooperative (YFOC) in Kochi Prefecture is one of such examples, which obtained FSC forest certification as a resource manager of the forest, which belongs to more than 1,200 small-scale forest owners. YFOC has successfully expanded sales of FSC-labeled timber in recent years. Most of their certified timber is purchased by house builders in urban cities including Osaka. This paper analyzes who desires FSC-certified timber from YFOC and why. Six case studies are reported, which reveal that ecology-oriented house builders are interested in using FSC certified timber because of traceability of the timber, price advantage from direct dealing, environmentally sound forest management of YFOC, and relatively high quality of the timber.  相似文献   

11.
陆文达  王冬香  凌楠 《林业研究》1999,10(2):124-126
lntroductionChina'sterritoryisvast,buttheforestedareaisless.About29%areaofChinaisdesertandbaremOuntains(Zhangetal.1997).ThefourthnationaIforestsurvey,whichwasconductedbytheMinistryofForestryin1989~1993,indicatesthat133.7millionhm2or13.92%oftheIandareaofChinaareforest.Thestockoflivingtreesis11.785bilIionm',ofwhich1o.1biIIionisinforest.Thenetgrowthofstandingvolumeiso.4biIIionm3peryear,whiIethecutisO.3billionm',ofwhichatleastonethirdisfarfueIwood.Sotheforestresourcesarenotrich,forestcoveri…  相似文献   

12.
The Regional Forest Agreement process has dominated Australian forest policy for the past decade. The RFA process set in place a mechanism by which benchmark conservation values were established for forest ecosystems, whilst addressing the needs of the timber industry. The outcomes of a number of RFA's have been fraught with controversy. Key stakeholder groups have shown disagreement with processes and outcomes of methods employed by government both in establishing conservation reserves and areas allocated to timber harvesting. This research uses non-linear techniques to examine the dynamical behavior in stakeholder responses and to identify patterns of behavior that may lead to prediction of stakeholder responses. The method developed in this research provides a bridge between social sciences and Chaos theory.1  相似文献   

13.
The Santiago Declaration identified seven criteria and 67 indicators for assessing the conservation and sustainable management of temperate and boreal forests. Data collected by the Forest Inventory and Analysis (FIA) program of the US Department of Agriculture Forest Service can be used to directly address at least 11 biological indicators.The FIA program has conducted periodic inventories of forestland for several decades. These inventories provide statistical estimates of forest area, timber volume, growth, removals, and mortality. Recent legislation has mandated that the Forest Service inventory the forestland of the US on an annual basis measuring the entire set of national sample plots over a 5-year period.This paper identifies which criteria and indicators can be addressed by FIA data; the scale at which it may be appropriate to use these data; and how recent changes will impact the Forest Service’s ability to provide information needed to address these indicators. Data from the two most recent inventories of Iowa (1974 and 1990) and Minnesota (1977 and 1990) are used to show how criteria and indicators relate to trends in forest composition and extent, timber resource utilization, and the population size of native and non-native trees. These two states have distinctly different forest resources, ranging from sparse to dense, and provide a good test of the effectiveness of using forest inventory data to provide criteria and indicator information at the state level.Analysis of the data for the last two inventories of Iowa and Minnesota reveals that the area of timberland has increased by 34 and 8%, respectively, while growing-stock volumes have increased by 47 and 23%. Volumes of most native species increased over the period, especially for pioneer species such as Juniperus virginiana L. [Little (1979). Agricultural Handbook No. 541, USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Ft. Collins, CO] (eastern red cedar). A notable exception was the 52% decline of Ulmus americana L. (American elm) due to the spread of Dutch elm disease. The number of non-native species also increased. In Iowa, the estimated number of live Ulmus pumila L. (Siberian elm) trees, a non-native species, went from 0 in 1974 to 675×103 in 1990. During the 1990 inventory of Minnesota another non-native species, Ailanthus altissima (Mill.) Swingle (tree of heaven), was sampled for the first time.  相似文献   

14.
中国林木资源利用管理政策主要包括森林采伐限额管理、凭证采伐林木制度、年度木材生产计划管理、木材运输管理和木材经营加工管理等内容,该文在参考《中华人民共和国森林法》和《中华人民共和国森林法实施条例》等法规和政策的基础上,梳理了中国木材资源利用管理政策,以促进国家木材政策体系的完善.  相似文献   

15.
本文介绍了美国农业部林务局(USDAFS,简称美国林务局)的林业计划体系及其计划分析工具,论述了美国林务局林业计划体系的组织形式和执行方式,特别是在制订不同层次的复杂的林业计划时所采用的民主、科学的管理手段,很值得我们学习与借鉴。  相似文献   

16.
Yusuhara Forest Owners’ Cooperative (YFOC) in Kochi Prefecture in Japan received its forest management certification from the Forest Stewardship Council (FSC) in 2000. YFOC is recognised as the resource manager of its members’ forests, and they were the first organisation to gain such certification in Japan. With the continuous efforts of selling FSC certified wood in the domestic housing construction market, YFOC has substantially increased their timber sales in recent years. It is a noteworthy event in Japanese small-scale forestry, which has been struggling with declining economic performance for many years. This paper analyses the detail of forestry activities and changes which occurred in YFOC after certification by FSC. An interesting effect of increasing economic performance is found to have come from an unexpected direction. It is concluded that the FSC certification system is a possible tool to revitalise Japanese small-scale forestry as well as obtain favourable environmental outcomes.  相似文献   

17.
We evaluate the economic efficiency of even- and uneven-aged management systems under risk of wildfire. The management problems are formulated for a mixed-conifer stand and approximations of the optimal solutions are obtained using simulation optimization. The Northern Idaho variant of the Forest Vegetation Simulator and its Fire and Fuels Extension is used to predict stand growth and fire effects. Interest rate and fire risk are found to be critical determinants of the superior stand management system and timber supply. Uneven-aged management is superior with higher interest rates with or without fire risk. Alterations in the interest rate affect optimal stocking levels of uneven-aged stands, but have only minor effects on the long-run timber supply. Higher interest rates reduce rotation length and regeneration investments of even-aged stands, which lead to markedly reduced timber supply. Increasing fire risk increases the relative efficiency of even-aged management because a single age cohort is less susceptible to fire damage over the course of the rotation than multiple cohorts in uneven-aged stands. Higher fire risk reduces optimal diameter limit under uneven-aged management and decreases optimal rotation length and planting density under even-aged management.  相似文献   

18.
森林认证对林产品贸易的影响   总被引:6,自引:0,他引:6  
郑仰南  蒋敏元 《林业研究》2002,13(4):316-318
森林认证在森林经营政策方面扮演了一个重要的补充角色并对林产品贸易起到了极其重要的影响。在短短的10余年间,森林认证已得到许多国家政府和林业部门的关注和认可。森林认证工作在中国刚刚起步,我们应该让更多的人了解森林认证并推动该项工作的发展。本文分析了森林认证对世界林产品贸易的影响,包括认证进出口国的利益、贸易流向、企业竞争、以及人们对认证林产品的需求,论述了森林认证对中国林产品贸易的影响,提出了森林认证对中国森林经营和林产品贸易的影响是机遇与挑战并存。参8。  相似文献   

19.
Abstract

On fragmented forest lands, ecosystem or landscape management approaches must cut across multiple ownerships. Therefore, communication and joint planning between neighboring landowners may be necessary for successful implementation of ecosystem management. This study examines landowners' interest in, and attitude toward, ecosystem management. Specifically, we use a survey and logistic regression model to explain landowner interest in joint planning as a proxy for their interest in ecosystem management. Survey results show that almost 70% of the landowners are interested in joint planning. However, most landowners require certain conditions be met before they would participate. Variables pertaining to attitudes and beliefs about ecosystem management or property rights, and receiving incentives for cooperation across the landscape are more important than demographic, land management, or spatial characteristics in explaining landowners' interest in joint planning. Landowners who believe in managing forests for environmental, wildlife and water quality as well as timber are more likely to be interested. The primary concern of those interested in joint planning is the impact it may have on their timber and/or land values. Planners who develop ecosystem management approaches that involve landowner cooperation should make the environmental impacts and benefits clear, and ensure that it will not reduce land and timber values.  相似文献   

20.
木兰林管局华北落叶松大径级材培育基地建设初探   总被引:1,自引:0,他引:1  
建设大径级用材林基地是解决中国目前木材供需矛盾问题的出路之一,对中国、我省以及木兰林管局大径材基地培育的现状进行了系统的总结,并对木兰林管局发展大径级材培育提出了相关对策。  相似文献   

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