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1.
We examine the financial aspects of three silvicultural systems to encourage the sustainability of valuable hardwood species in mixed-dipterocarp forests of southwest Sri Lanka. We compare the net present value (NPV) of the current forest management approach (diameter limit harvests) with shelterwood harvests that promote light hardwood timber species. In this analysis, we also consider the potential of enrichment planting various precious timber (Diospyros quaesita — calamander), and non-timber forest product (NTFP) species (Caryota urens — fishtail palm; Elettaria cardamomum var. major — cardamom; Calamus zeylanicus — rattan) in conjunction with timber harvests. Two real (inflation adjusted) discount rates were used, 4 and 6%, respectively. Results show that when real discount rates are low (4%), and advance regeneration is present, NPV is highest for the one-cut shelterwood (US $9983 ha−1). At a high discount rate (6%), reflecting the current short-term concession system and unstable rights to harvest, and where no advance regeneration was present, the diameter limit system (US $7173 ha−1) was the optimum. On sites with advanced regeneration, the one-cut shelterwood system is clearly preferable. For all but rattan, shelterwood treatments provide higher NPVs for NTFPs than diameter limit cuttings primarily because of the higher light regimes and more growing space made available early in the rotation. The value for tea cultivation (US $26,000 ha−1) far exceeds the value of managing these lands for timber alone, explaining the dramatic expansion in tea plantations on private lands. However, our results suggest that managing these lands for a combination of timber and enrichment plantings of NTFPs (US $23,000 ha−1) can be comparable to tea plantations. By managing for NTFPs and timber, forest managers have new opportunities to solve the old problems of high-grading and land-use conversion.  相似文献   

2.
The roots of American ginseng have been harvested from the hardwood forests of the eastern United States, alongside timber, since the mid-1700s. Very little is known about this non-timber commodity relative to timber, although significant volumes of ginseng root have been harvested from the same forests along with timber. The harvest of ginseng correlated positively and significantly with hardwood forest area, hardwood growing stock volume, and timber removals. Also, it correlated with hardwood growing stock on public forestlands in the region. The annual wholesale value of American ginseng was estimated at approximately $26.9 million compared to annual stumpage value of harvested hardwood timber of just over $1.27 billion. The volume of ginseng root harvested from natural forests represents substantial extraction of biomass, and the associated value represents substantial income for people living in an economically marginalized region. Co-management of eastern hardwood forests for timber and non-timber forest products could improve local economies and better conserve the biodiversity of these forests.  相似文献   

3.
Sustained yield policies designed to ensure an even annual flow of timber harvests remain the most common approach to forest management on public lands in Canada. Such policies have been criticized on the environmental grounds that timber production is emphasized at the expense of other values, and on the economic grounds that policy-makers try to maximize the harvests level without regard for economic optimality (measured by whether or not revenues cover variable costs of production). In a case study from Northern Ontario, we used a spatially explicit harvest scheduling model to evaluate financial outputs for various scenarios, introducing different timber flow constraints, as well as varying utilization policies. We show that current policies do contribute to firms harvesting at uneconomic levels. More specifically, our results show that reducing harvest levels could increase firm profitability (measured in an increase in net revenues associated with harvesting operations). We estimate that to meet the annual allowable cut (AAC) of approximately 375,000 cubic metres (m3), the firm loses $500,000 annually (measured by the amount by which total harvesting costs exceed log values delivered at the mill). Reducing the target AAC to just under 300,000 m3 leads to a reversed situation, harvesting revenues now exceeding costs by $1.2 million annually. Dropping the even flow constraint leads to even higher annual profitability of $3.5 million, with the drawback that harvesting levels show significant variation over the 100-year planning period. Our results also show that the largest factor influencing the level of profitability is attributed to access costs (principally roading costs). In this case, other harvesting policies, such as utilization standards, may not be significant factors affecting costs in this region of Northern Ontario.  相似文献   

4.
Widespread commercial harvesting of wild edible mushrooms from the forests of the Pacific Northwest United States (PNW-US) began 10–15 years ago. A large proportion of suitable forest habitat in this region is managed by the Forest Service (US Department of Agriculture) and Bureau of Land Management (US Department of the Interior). These lands are managed under an ecosystem management philosophy that entails multiple-use, sustainable forest product harvesting, resource monitoring, public participation in forest management issues, and holistic planning. Managing the harvest of edible mushrooms engages every aspect of this management philosophy. We examine a variety of issues raised by mushroom harvesting and how these issues interact with forest ecosystem management choices. We discuss regulations currently being used by managers to conserve the mushroom resource while further information is gathered, unique challenges and considerations inherent to sampling fungi, and current research and monitoring activities in the Pacific Northwest. Although current scientific evidence suggests that harvesting likely will not harm the resource in the short term, no statistically-based monitoring information exists about the cumulative impacts of intensive and widespread commercial harvesting over long-time periods. We outline a three pronged approach to long-term monitoring of the resource: (1) tracking harvest quantities in areas with intense commercial harvests; (2) sampling productivity in areas with no mushroom or timber harvests; and (3) conducting research to model the relations between forest management and mushroom productivity. Public participation and a broad collaboration among public land management agencies, private forest landowners, forest managers, researchers, and research organizations will make this approach cost effective and the results widely applicable.  相似文献   

5.
Timber investment returns were estimated for the principal exotic and selected native species in the Southern Cone of Latin America and in the Southern United States. Exotic eucalyptus plantations in South America were most profitable, with internal rates of returns (IRRs) ranging from 13% to 23%, followed by exotic loblolly pine, with IRRs from 9% to 17%. Average loblolly pine plantation returns in the US South were less profitable, with an IRR of about 9.5%, and natural forest management in the South had IRRs of 4% to 8%. Subtropical native species plantations of the best araucaria and nothofagus species had reasonable financial returns, with IRRs ranging from 5% to 13%. Subtropical or tropical native forests had fewer commercial timber species, and had much lower growth rates and returns. Their IRRs were less than 4%, or even negative for unmanaged stands. State subsidy payments for forest plantations or for timber stand improvements increased IRRs somewhat and reserving areas for environmental protection reduced their IRRs slightly. Including land costs in the cash flows decreased these internal rates of return substantially. Natural stand returns in Latin America were much less than those of plantations, but management of those stands offered better rates of return than only holding the land.  相似文献   

6.
This study reports the results from a 5 year simulation of forest thinning intended to reduce fire hazard on publicly managed lands in the western United States. A state simulation model of interrelated timber markets was used to evaluate the timber product outputs. Approximately 84 million acres (34 million hectares), or 66% of total timberland in the western United States, is publicly managed; of this 78 million acres (31.6 million hectares) are managed by the federal agencies. We considered three budget scenarios using a least-expensive highest-hazard area first policy. Our intention with this simulation is not to definitively answer questions about where or how to conduct treatments to reduce fire hazard on public lands but rather to begin to develop tools that can be used to inform such a policy debate. Considerable development of this tool is still needed before it will be useful for that purpose. Our initial simulations nonetheless provide insight into what might happen if available funds were allocated to the least-expensive highest-hazard areas across the west. Using assumptions of (1) an annual “subsidy” (payments for treatments), (2) the treatment costs, (3) the priority ranking by forest type, (4) fire hazard level, and (5) the wildland–urban interface (WUI) status, the simulation suggests that lodgepole pine (Pinus contorta), ponderosa pine (Pinus ponderosa), spruce (Picea spp.)–fir (Abies spp.) and Douglas-fir (Pseudotsuga menziesii) are projected to be major forest types treated in the West. A combination of our treatment ranking assumptions and the low total treatable WUI acres on public timberland caused the model to concentrate almost exclusively on all the WUI stands and non-WUI ponderosa pine forest type at the budget of $150 million and $300 million. With the further increase of budget, a large proportion of treated acres are lodgepole pine and spruce–fir forest types using the thin-from-below approach. About 41% of the volume removals are sawtimber for all the public timberland treated under the low budget scenario ($150 million/year), 58 for moderate budget ($300 million/year), 50 for the high budget scenario ($1500 million/year). Under the moderate budget case ($300 million a year), about 19% of the total wood removed is projected to come from trees less than 5-inches (12.7 cm) in diameter at breast height (dbh), and another 16% of the biomass is expected from trees 20-inches (50.8 cm) dbh and above.  相似文献   

7.
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   

8.
9.
世界原木出口量呈下降趋势;加工的半成品、产品出口量呈增长趋势。木材出口国和地区为北美、欧洲、苏联和东南亚,而进口国和地区主要有日本、欧洲、中国和南朝鲜。文中研究了木材贸易与经济周期的关系以及贸易保护主义和集团化倾向对木材贸易的影响。建议我国木材进出口应实行多元化和协调一致共同对外的方针,同时要优化木材产品结构并抑制某些木材产品的过热消费。  相似文献   

10.
Activities associated with timber harvesting have occurred within floodplain forests in the southern United States for nearly two hundred years. However, it is only in the last ten years that any information has become available about the effects of harvesting on the ecological functions of this valuable resource. Hydrology is the driving influence behind all ecological processes in floodplains, and timber harvesting alone usually has little long-term effect on hydroperiod. However, logging roads, built in association with harvest sites, can sometimes alter hydroperiod to the extent that vegetation productivity is raised or lowered. There is no evidence that harvesting followed by natural regeneration represents a threat to ground or surface water quality on flood plain sites, as long as “best management practices” are followed. Harvested floodplains may increase or have little effect on decomposition rates of surface organic matter. The nature of the effect seems to be controlled by site wetness. Data from recently harvested sites (i.e. within the last ten years) suggest that vegetation productivity is maintained at levels similar to those observed prior to harvests. During the early stages of stand development, tree species composition is heavily influenced by harvest method. Similarly, amphibian populations (monitored as bioindicators of ecosystem recovery) seem to rebound rapidly following harvests, although species composition may be different from that of unharvested stands.  相似文献   

11.
This paper addresses the effects of economic transition policies on forestry in China. The effects of de-collectivization and market liberalization on the forest land area and timber harvest are studied using panel data from four provinces covering the period 1978–1995. Fixed effects ordinary least squares models for forest land cover and annual harvests per hectare are estimated, allowing for differences across provinces and prefectures in northern and southern China. The results show that land tenure reform in general has had a positive effect on forest land expansion, but the absolute size of the effects varies from province to province. The positive impact of the reform on timber harvesting has not taken place at the cost of forest land cover. The claim that market liberalization leads to over-harvesting of forest resources in developing countries is not supported by our results.  相似文献   

12.
The effect of changes in roundwood harvests in Norway on the harvests in rest of the world is examined using a global forest sector model. About 60–100% of the harvest change in Norway is offset by an opposite change in the rest of the world. Such leakage rates vary over time, wood category, background scenario, and the size of the harvest change. Asymmetries between the effects of increasing and decreasing the harvests also exist. Hence, the magnitude of leakage rate is case specific, though considerable. Under tightening wood supply there is less need/room to respond to harvest increase/decrease in Norway with incremental/reduced harvests elsewhere. When the use of global forest resources intensifies with increasing wood demand in the future, leakage rates can be smaller than today. It is important to account for harvest leakage in order to avoid overestimating the climate benefits of policies that decrease or increase roundwood harvests. For instance, for full carbon sequestration benefits of increasing harvests for harvested wood products, creating fresh additional demand for these products should be prioritized. Else the origin of raw material and the place of production for these products may change instead of their stock.  相似文献   

13.
The US has a century of experience with the development of forest policies that have benefited from or been influenced by economic research activities in the forest sector. At the same time, increasing rigor in policy debates stimulated economics research. During the past four decades economic research has evolved to include increased understanding of consumer demands, producer behavior, landowner behavior and timber resource conditions. Bio-economic models have evolved that combine economic and resource models; these have been used in the US to provide the basis for forecasting future resource and market trends and to shape public perceptions. Economics research has also contributed frameworks for policy analysis using approaches like scenario planning to help decision-makers gauge uncertainty.  相似文献   

14.
Schultz  Robert P. 《New Forests》1999,17(1-3):71-88
Loblolly pine (Pinus taeda L.) was a minor component of the vast natural forests of the southern United States before the region was settled by immigrants. Extensive planting and natural regeneration of cutover forest land and abandoned farmland between 1930 and 1990 made loblolly the leading timber species in the United States. It now predominates on 13.4 million ha (45 percent) of the commercial forest land in the southern United States (between latitudes 28° N and 39° N and longitudes 75° W and 97° W) and directly or indirectly provides 110,000 jobs and $30 billion to the economy of the region. The extreme versatility of loblolly has also provided important environmental contributions to most southern states. These include landscape beautification, erosion control, soil amelioration, excellent wildlife habitat, and outstanding recreational opportunities. Incorporating existing pest management strategies into silvicultural systems can produce substantial and long-lasting insect and disease control with little cost or physical effort. Introductions of loblolly into numerous countries around the world (especially China, Brazil, and Argentina) have proven to be very successful, environmentally sound, and commercially profitable. In some locations, loblolly grows much faster than on sites of similar quality in the southern United States.  相似文献   

15.
Forest managers often seek to balance economic benefits from timber harvesting with maintenance of habitat for wildlife, ecosystem function, and human uses. Most research on the relationship between avian abundance and active timber management has been short-term, lasting one to two years, creating the need to investigate long-term avian responses and to identify harvest thresholds when a small change in habitat results in a disproportionate response in relative abundance and nest success. Our objectives were to identify trends in relative abundance and nest success and to identify landscape-scale disturbance thresholds for avian species and habitat guilds in response to a variety of harvest treatments (clear-cuts, heavy and light partial harvests) over 14 years. We conducted point counts and monitored nests at an industrial forest in the central Appalachians of West Virginia during 1996-1998, 2001-2003, and 2007-2009. Early successional species increased in relative abundance across all three time periods, whereas interior-edge and forest-interior guilds peaked in relative abundance mid-study after which the forest-interior guild declined. Of 41 species with >10 detections, four (10%) declined significantly, 13 (32%) increased significantly (only three species among all periods), and 9 (22%) peaked in abundance mid-study (over the entire study period, four species had no significant change in abundance, four declined, and one increased). Based on piecewise linear models, forest-interior and interior-edge guilds’ relative abundance harvest thresholds were 28% total harvests (all harvests combined), 10% clear-cut harvests, and 18% light partial harvests, after which abundances declined. Harvest thresholds for the early successional guild were 42% total harvests, 11% clear-cut harvest, and 10% light partial harvests, and relative abundances increased after surpassing thresholds albeit at a reduced rate of increase after the clear-cut threshold. Threshold confidence intervals for individual species overlapped their guild threshold intervals 91% of the time. Even though relative abundance of most species (80%) did not decline as the area affected by timber management increased, implementing management at or below our approximate forest-interior and interior-edge harvest thresholds would reduce the number of declining species by half, maintain higher relative abundances of four species with a net decline in abundance but that peaked in abundance mid-study, and maintain higher relative abundances of ten additional species. In contrast, this management strategy also would prevent the increase in relative abundance of seven species and limit the increase in abundance of three species that increased throughout the study.  相似文献   

16.
Abstract

Changing forest policies in both riparian and upland areas to help protect threatened and endangered species have contributed to the reduction of timber harvests in western Washington. The economic, biodiversity, and environmental impacts of these policy actions have been substantial. Policy simulations across 9.4 million acres of timber-land show that relative to proactive management strategies, current habitat conservation and environmental programs (largely based on a reservation strategy) result in net present value reductions to forestland owners of $9.9 billion. Accompanying these asset value reductions are employment losses (sustained) of 30% and tax receipt losses of 26%. The policy simulations further demonstrate that proactive management will not decrease the long-term percentage of the upland landscape occupied by functionally old forests relative to the reservation strategy. In the riparian area, adoption of a reservation strategy actually decreases (by 29%) the percent of the landscape occupied by functionally old forests relative to a proactive management approach. These results illustrate the importance of proactively managing western Washington forests to provide maximum functionally old forest habitat for endangered upland animals (such as the northern spotted owl and the marbled murrelet) as well as riparian species.  相似文献   

17.
National government policies on preventing global warming are becoming increasingly important in Japan, especially since the Kyoto Protocol became effective in 2005, and the first commitment period began in 2008. The Forestry Agency has combined policies promoting domestic forestry with those to prevent global warming and has developed a 10-year action plan. However, the forest resource database and related statistics represent serious problems in the forest management system in Japan and in the administrative work of the prefectural governments that manage the database. The database contains much incorrect data, which is difficult to correct because of insufficient budget and staff. The budget problem has seriously affected the entire administrative section of the Forestry Agency since the 1990s. Environmental taxes related to forests have recently been introduced in many prefectures, although the total revenue generated is small. The basic problem with the database is that the National Land Survey is incomplete and, consequently, the forest land size information in the database is unreliable. Furthermore, because prefectural governments are not required to report statistics on timber harvests, the cutting volume in each municipality is uncertain. Considering this situation, it may be difficult for the private forest sector to contribute greatly to the Kyoto Protocol without changes in the forest management system by both national and prefectural governments.  相似文献   

18.
We assessed the impact on the world forest sector of a progressive elimination of illegal logging. The analysis compared predictions from 2007 to 2020, with and without a gradual reduction of illegally logged industrial roundwood from 2007 to 2011. A large part of the curtailment of timber supply due to the stoppage of illegal logging would be compensated by increased legal production incited by higher prices. As a result, without illegal logging the world annual production of industrial roundwood would decrease by no more than 1%, even though it would decrease by up to 8% in developing countries. World prices would rise by 1.5 to 3.5% for industrial roundwood and by 0.5 to 2% for processed products, depending on the assumption on illegal logging rates. World consumer expenditures for wood products and producer revenues would rise by 1 to 2% without illegal logging. World value added in forest industries would remain the same. However, the changes in consumer expenditures would be more than double the changes in producer revenues in countries dependent on illegally logged timber of domestic or foreign origin such as Indonesia and China. Symmetrically, changes in producer revenues would be almost twice the changes in consumer expenditures in countries with little illegal logging and efficient industries, such as Canada, Germany and the United States. Value added in forest industries would decrease most in countries with heavy illegal logging (12% in Indonesia and up to 9% in Brazil), and it would increase most in Germany, Canada (4%), and the United States (2%). Without illegal logging, the world forest inventory would increase slightly, as the increase in developing countries would more than compensate the decrease in developed countries.  相似文献   

19.
The global forest sector model EFI-GTM was applied to assess regional impacts in Europe of increased timber supply caused by potential acceleration of forest growth in Europe. The EFI-GTM is a multi-periodic partial equilibrium model, which contains 31 European regions and 30 regions for the rest of the world, and trade between the regions. The endogenous sectors include 26 forest industry products and six wood categories. Three alternative forest growth scenarios were analysed: a base line assuming the present annual rate of growth in the European countries, and two accelerating growth scenarios corresponding to a 20 and 40% increase after 20 years in the forest growth relative to the baseline growth. In the accelerated growth scenarios equilibrium prices for logs and sawnwood decreased significantly from the baseline levels, whereas the other forest product prices were not affected much. Depending on region and timber category, the log prices in 2020 were 7–9 and 13–17% lower than the base line prices in the medium and high forest growth scenarios, respectively. For sawnwood, the corresponding price decreases were 2 and 3.5–4.5%. In Western Europe, log harvest and sawnwood production increased because accelerated forest growth substituted for imports of these commodities from Russia and Eastern European countries. This decreased the harvests in Russia and Eastern Europe relative to the base case. In all the three forest growth scenarios the forest owners income as well as the forest industry profit increase over time.  相似文献   

20.
The objective of this study was to project the effects on the world forest sector of eliminating quickly all import tariffs. The projections were done for two scenarios: (1) progressive tariff reduction according to the current schedule of the General Agreement on Tariffs and Trade; (2) complete elimination of all tariffs within the Asia-Pacific Economic Cooperation (APEC) countries. The projections were obtained with the global forest products model (GFPM), for the years 1998–2010. The model gave market equilibrium projections of quantities produced, consumed, imported and exported for each of 180 countries, and for 14 commodity groups, covering roundwood, sawnwood, wood-based panels, pulp and recycled fibers and paper and paperboard. The model also projected world equilibrium prices. The results showed that, with or without ATL agreement, the world consumption and trade of all forest products would continue to grow along the historical trends, and the world prices of forest products would increase moderately. With the elimination of tariffs in APEC countries, the projected world production and consumption of all products would change little (less than 0.5%). The tariff reduction effects would be larger for trade, and the commodity composition of world trade would shift from raw materials to more processed products. The timber harvest would change in a number of countries, but the net effect at the world scale would be small. While the US consumption and production of forest products would change little, the US would reduce its export of logs and increase exports of most processed products. The US timber harvest was expected to be indistinguishable compared to what it would be in the absence of the Accelerated Tariff Liberalization agreement.  相似文献   

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