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1.
We used national scenario analyses to examine the effects of harvesting intensity on the development of forest resources, timber supply, carbon balance, and biodiversity indicators of Finnish forestry in nine 10-year simulation periods (90-year simulation period) under the current climate. Data from the 11th National Forest Inventory of Finland were used to develop five even-flow harvesting scenarios for non-protected forests with the annual harvest ranging from 40 to 100 million m3. The results show that the highest annual even-flow harvest level, which did not decrease the growing stock volume over the 90-year simulation period, was 73 million m3. The total 90-year timber production, consisting of harvested volume and change in growing stock volume, was maximized when the annual harvest was 60 million m3. Volume increment increased for several decades when harvested volume was less than the current volume increment. The total carbon balance of forestry was the highest with low volume of harvested wood. Low harvested volume increased the values of biodiversity indicators, namely volume of deciduous trees, amount of deadwood and area of old forest.  相似文献   

2.
Forest managers and policy-makers are being encouraged to incorporate carbon sequestration as a criterion for decision-making. This is a great challenge for small-scale forestry where the conspicuous lack of practical knowledge available for managers prevents the implementation of criteria to promote carbon sequestration. The carbon simulation model CO2FIX combined with local data could provide valuable information for C sequestration in these small-scale forestry systems. The research reported here focuses on community forestry located in the Juarez Mountain Range (Oaxaca State, Mexico), and analyzes the influences of forest management and wood-use (20 scenarios based on five forest management plans and four wood-use strategies) on the changes of C stock (biomass C, soil organic C, products C and fuelwood C) over time. The comparison of the whole stocks to reference results show that group-selection, based on an uneven-aged forest management system involving small patches, has only about half the C benefit relative to clear-cutting harvesting. A forest management strategy focused on oak logwood has a lower C benefit (70 %), and a forest management strategy focused on oak fuelwood has a higher C benefit (120 %) relative to the average of the studied wood-use strategies. Thus, in the study area forest managers and policy-makers who wish to mitigate climate change should increase the rotation period from 40 to 50 years in clear-cutting areas, continue with 40 years in group-selection areas, and promote the use of oak for bioenergy.  相似文献   

3.

Key message

High-elevation forests in the Alps protect infrastructure and human lives against natural hazards such as rockfall, flooding, and avalanches. Routinely performed silvicultural interventions maintain the required stand structure but are not commercially viable in remote forests due to high operational costs. Financial subsidies for the management of high-elevation protection forests are an efficient strategy to ensure sustainable forest cover.

Context

Presently, many high-elevation forests in the Alps are managed in order to ensure the provision of ecosystem services with emphasis on the minimization of natural hazards.

Aims

We studied the possible economic performance of a high-elevation protection forest from an owner’s perspective. We investigated whether the increase in productivity due to climate change and a favorable market for the dominating cembran pine (Pinus cembra L.) are sufficient for profitable timber production in protection forests.

Methods

We simulated the standing timber stock and the soil carbon pool for a 100-year period with climate-sensitive models and compared harvesting costs with expected revenues. Our scenarios included different climates, intensities of timber extractions, parameters of the timber market, and the availability of government subsidies.

Results

Overall, the productivity of forests increases by approximately 15% until the end of the century. In a zero-management scenario, the forest accumulates carbon both in the aboveground biomass and the soil. In the case of an extensive management with moderate timber extractions every 50 years, the carbon stocks decline both in biomass and soil. A more intensive management scenario with extractions every 30 years leads to substantial losses of the soil and biomass carbon pools. In addition, the stand structure changes and the protective function of the forest is not sustainably ensured. Timber production can be economically successful only with high selling prices of cembran pine timber and the availability of governmental subsidies for forest management. The admixed European larch (Larix decidua Mill.) contributes only marginally to the economic success. The main challenge are harvesting costs. The costs of timber extraction by a long-distance cableway logging system exceed the value of the harvested timber.

Conclusion

The intensification of forest management cannot be recommended from the perspective of timber production, sustainable forest management, and protection against natural hazards. Our simulation experiment shows that the extraction of timber at decadal intervals depletes the carbon stock that is insufficiently replenished from aboveground and belowground litterfall. Leaving the forest unmanaged does not impose a particular threat to stand stability and is under the encountered situation, a justified strategy.
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4.
Illegal logging has attracted worldwide attention, and some measures, such as timber procurement policies and timber regulations, have been taken. However, there are no studies that examine the governance of illegal logging using game theory. This paper applies game theory to analyze the subsidy policy for governing illegal logging as well as the effects of the subsidy on the benefits of suppliers and operators of forest products. The results show that controlling illegal logging has an impact on exporting enterprises, and the effects produced by subsidies and non-subsidies are different for enterprise. Enterprises that receive subsidies will occupy foreign markets and gain additional profits, while enterprises that are not subsidized will exit foreign markets. The amount of subsidies is related to enterprise’s governance cost. The benefit for operators and suppliers depend on the combination of supervision level and forest products’ legality. The critical point of regulation of operators is related to regulatory costs, the additional benefits of weak supervision of suppliers, and penalties for regulatory failure. The critical point for suppliers to select legal raw materials is related to suppliers’ operating costs, gray income, and the degree of punishment.  相似文献   

5.
The demand for wood as construction material, renewable source for energy and feedstock for chemicals is expected to increase. However, timber increments are currently only partly harvested in many European mountain regions, which may lead to supply shortages for local timber industries, decreases in forest resistance to disturbances and functioning as protection from gravitational hazards. Using an inventory-based forest simulator, we evaluated scenarios to increase wood mobilization in the 7105-km2 Swiss canton of Grisons for the period 2007–2106. Scenarios varied with respect to landscape-scale harvesting amounts and silvicultural strategies (low vs. high stand-scale treatment intensity) and accounted for regulations and incentives for protection forest management. With 50 and 100% increases of harvests, the current average growing stock of 319 m3 ha?1 was simulated to be reduced by 12 and 33%, respectively, until 2106 in protection forests of Northern Grisons, where management is prioritized due to subsidies. Outside protection forests and in Southern Grisons, growing stock was simulated to continually increase, which led to divergent developments in forest structure in- and outside protection forests and in the Northern and Southern Grisons. The effect of silvicultural strategies on simulated forest structure was small compared to the effect of future harvesting levels. We discuss opportunities and threats of decreasing management activities outside protection forests and advocate for incentives to promote natural regeneration also outside protection forests to safeguard long-term forest stability.  相似文献   

6.

Timber use in central Europe is expected to increase in the future, in line with forest policy goals to strengthen local wood supply for CO2-neutral energy production, construction and other uses. Growing stocks in low-elevation forests in Switzerland are currently high as exemplified by the Swiss canton of Aargau, for which an average volume of 346 ± 16 m3 ha−1 was measured in the 3rd Swiss National forest inventory (NFI) in 2004–2006. While this may justify a reduction of growing stocks through increased timber harvesting, we asked whether such a strategy may conflict with the sustainability of timber production and conservation goals. We evaluated a range of operationally relevant forest management scenarios that varied with respect to rotation length, growing stock targets and the promotion of conifers in the regeneration. The scenarios aimed at increased production of softwood, energy wood, the retention of potential habitat trees (PHTs) and the conversion to a continuous cover management system. They were used to drive the inventory-based forest simulator MASSIMO for 100 years starting in 2007 using the NFI sampling plots in Aargau. We analyzed model outputs with respect to projected future growing stock, growth, timber and energy yield and harvesting costs. We found growing stock to drop to 192 m3 ha−1 in 2106 if business-as-usual (BAU as observed between the 2nd and 3rd NFI) timber volumes were set as harvesting targets for the whole simulation period. The promotion of conifers and a reduction of rotation lengths in a softwood scenario yielded 25% more timber over the whole simulation period than BAU. An energy wood scenario that reduced growing stock to 200 m3 ha−1 by 2056 and promoted the natural broadleaved regeneration yielded 9% more timber than BAU before 2056 and 30% less thereafter due to decreasing increments. The softwood scenario resulted in higher energy yield than the energy wood scenario despite the lower energy content of softwood. Retaining PHT resulted in a reduction of timber harvest (0.055 m3 ha−1 yr−1 per habitat tree) and higher harvesting costs. Continuous cover management yielded moderate timber amounts throughout the simulation period, yet sustainably. Considering climate change, we discuss the risks associated with favoring drought- and disturbance-susceptible conifers at low elevations and emphasize that continuous cover management must allow for the regeneration of drought-adapted tree species. In conclusion, our simulations show potential for short-term increases in timber mobilization but also that such increases need to be carefully balanced with future forest productivity and other forest ecosystem services.

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7.
The effects of profit and land value tax on harvesting decisions of nonindustrial private forest owners are investigated. We use a model of a utility-maximizing forest owner with amenity preferences for timber, which extends the basic two-period harvesting model to include both thinning and clear-cutting harvests. It is demonstrated that with no amenity preference, the profit and land value taxes are neutral to clear-cutting and thinning decisions. Under small to medium amenity preferences, the profit tax decreases the optimal clear-cutting volumes. However, the effect on thinning may be positive or negative, depending on the amenity preference level. The total effect of the profit tax on the short-run timber supply is negative. The effects of the land value tax contrast with those of the profit tax. Also, a tax regime with a lowered profit tax rate combined with a land value tax is analysed. It is shown to be able to bring Pareto-improvement to a regime that uses a higher profit tax but no land value tax.  相似文献   

8.
The effects of profit and land value tax on harvesting decisions of nonindustrial private forest owners are investigated. We use a model of a utility-maximizing forest owner with amenity preferences for timber, which extends the basic two-period harvesting model to include both thinning and clear-cutting harvests. It is demonstrated that with no amenity preference, the profit and land value taxes are neutral to clear-cutting and thinning decisions. Under small to medium amenity preferences, the profit tax decreases the optimal clear-cutting volumes. However, the effect on thinning may be positive or negative, depending on the amenity preference level. The total effect of the profit tax on the short-run timber supply is negative. The effects of the land value tax contrast with those of the profit tax. Also, a tax regime with a lowered profit tax rate combined with a land value tax is analysed. It is shown to be able to bring Pareto-improvement to a regime that uses a higher profit tax but no land value tax.  相似文献   

9.
Great importance has been attached to the “Agriculture-Rural-Farmer” issue by the Communist Party of China (CPC) Central Committee and the State Council of China. In recent years, a series of agricultural supporting subsidy policies, such as direct subsidies to grain, seed, material, and machinery purchases have been enforced, and these policies have greatly promoted the agricultural production and the incremental income of farmers. However, from the perspective of increasing the farmers’ income, although the subsidy coverage is expanding from fields to hilly areas where the farmers have made major contributions to the supply of wood and ecological security, the farmers have a low income without enough aid from the forestry fiscal subsidy policy. Foresters cannot enjoy the same policy support as farmers, because the level of forestry fiscal subsidies is obviously lower than the level of agricultural subsidies. Therefore, based on investigation, this article suggests giving more support to forest workers in terms of the promotion and optimization of forestation, forest tending, seeds and insurance subsidies, and further expanding the forestry subsidies’ category and scope and improving its standards.  相似文献   

10.
Forest management can result in net losses of carbon stock. To quantify the impact of the management it is important to assess losses or gains of carbon, as well as the sustainability of the management system. This study quantified the impact management under a Small-Scale Sustainable Forest Management Plan, which is a recently created category of authorized management for small managers in the state of Amazonas, Brazil. Impact was quantified on the number of individuals, the biomass of natural regeneration, and the damage to the remaining trees 2 months after logging. The impact of these changes on carbon stock was estimated. The study was carried out in the Uatumã Sustainable Development Reserve, Amazonas, Brazil, where two areas of small-scale forest management and one control were evaluated. Average total carbon stock previous to logging was estimated at 161.25 ± 9.66 MgC ha?1. Two months after logging, reductions were found of 3% in one managed area (MA1) and 8.3% in the other (MA3), including the carbon stock from the harvested timber. For each harvested tree, the logging caused damage to 12 trees in MA1 and four trees in MA3. The reductions in carbon stock and number of trees damaged per harvested tree were less than the reductions found for higher impact forest management and other experiences in community forest management. No significant alteration was found in the carbon stock of natural regeneration. However, there was an increase in the number of individuals, both in the logged areas and in their respective control areas.  相似文献   

11.
An increase in the amount of harvested wood products (HWP) from sustainable forestry would help to reduce levels of atmospheric carbon. In the first commitment period of the Kyoto Protocol (2008–2012), this carbon stock effect of HWP is ignored, and forest harvesting is treated as an instantaneous emission of carbon dioxide. However, in the next commitment period of the United Nations Framework Convention on Climate Change from 2013, the carbon stock changes resulting from HWP will be taken into account in the national greenhouse gas inventories. The Japan Wood Research Society called for a roundtable conference of eight research societies, industrial associations, and nongovernmental organizations that are involved with wood utilization. At the conference, accounting approaches for HWP were discussed and a consensus was reached that the stock change approach should be adopted in the next commitment period.  相似文献   

12.
工业化国家林业产业当前面临的主要问题是环境污染对大面积森林构成的严重危胁和对分散的私有林无法进行现代化经营。此外,尚有财政危机和某些国家的林产品过度依赖进口等问题。在90年代,甚至更长的时期内,发达国家林业产业政策的调整方向是,保护和改造现有林,通过实施分类经营战略发挥森林的多种效益,兼用行政和经济手段引导私有林的发展,进一步调整林产品结构和大力发展木材培育业。  相似文献   

13.
Community-based forest management, such as Community Forest Enterprises (CFEs), has the potential to generate positive socioenvironmental and economic outcomes. We performed a detailed survey of financial and production parameters for 30 of the approximately 992 CFEs in Mexico in order to estimate costs, income, profits, and sustainability of harvest levels for forest management, harvest, and sawmilling. Fourteen of the 30 CFEs harvested more timber than they grew in 2011, suggesting issues with sustainability, but only two of these had harvest far above annual growth, and five of those were only a fraction more than annual growth. All of the 30 CFEs except one made profits in forest management and timber growing. For timber harvesting, 22 of 30 CFEs made profits, but the losses were small for the other CFEs. For the 23 CFEs with sawmills, 18 made profits and five had losses; the greatest returns for the CFEs accrued to those with sawmills for lumber production. On average, the CFEs surveyed had high costs of production relative to other countries, but the CFEs were still profitable in national lumber markets. If Mexico were to begin importing large amounts of lumber from lower cost countries, this could pose a threat to CFE profitability.  相似文献   

14.
This paper presents a short-run roundwood supply analysis of self-employed Norwegian forest owners, based on a two-period utility maximising consumption-savings model. The supply function was estimated by applying the Tobit model on an unbalanced panel of approximately 160 Norwegian farmers, from 1976 to 1997, representing a total of 3413 observations. Simultaneity between the single forest owner's harvesting level and his individual tax rate was allowed by estimating simultaneous equations Tobit models. The current roundwood price and standing stock per hectare had significant positive impacts on the supply, while harvesting costs, age of the owner, tax rate and lagged roundwood price (representing expected price) had negative impacts. Price and cost elasticities were relatively sensitive to the prices forecasted for the owners who did not supply roundwood in a given period. These results suggest that price subsidies and operating subsidies, as well as tax relieves, could increase the harvest level, which is considerably lower than the sustainable harvest level. An operating subsidy seems at least as efficient as a price subsidy, while tax reliefs are the least efficient of the three policy means.  相似文献   

15.
Temperate forests are an important carbon sink, yet there is debate regarding the net effect of forest management practices on carbon storage. Few studies have investigated the effects of different silvicultural systems on forest carbon stocks, and the relative strength of in situ forest carbon versus wood products pools remains in question. Our research describes (1) the impact of harvesting frequency and proportion of post-harvest structural retention on carbon storage in northern hardwood-conifer forests, and (2) tests the significance of including harvested wood products in carbon accounting at the stand scale. We stratified Forest Inventory and Analysis (FIA) plots to control for environmental, forest structural and compositional variables, resulting in 32 FIA plots distributed throughout the northeastern U.S. We used the USDA Forest Service's Forest Vegetation Simulator to project stand development over a 160 year period under nine different forest management scenarios. Simulated treatments represented a gradient of increasing structural retention and decreasing harvesting frequencies, including a “no harvest” scenario. The simulations incorporated carbon flux between aboveground forest biomass (dead and live pools) and harvested wood products. Mean carbon storage over the simulation period was calculated for each silvicultural scenario. We investigated tradeoffs among scenarios using a factorial treatment design and two-way ANOVA. Mean carbon sequestration was significantly (α = 0.05) greater for “no management” compared to any of the active management scenarios. Of the harvest treatments, those favoring high levels of structural retention and decreased harvesting frequency stored the greatest amounts of carbon. Classification and regression tree analysis showed that management scenario was the strongest predictor of total carbon storage, though site-specific variables were important secondary predictors. In order to isolate the effect of in situ forest carbon storage and harvested wood products, we did not include the emissions benefits associated with substituting wood fiber for other construction materials or energy sources. Modeling results from this study show that harvesting frequency and structural retention significantly affect mean carbon storage. Our results illustrate the importance of both post-harvest forest structure and harvesting frequency in carbon storage, and are valuable to land owners interested in managing forests for carbon sequestration.  相似文献   

16.
Carbon stocks and stock changes in a chronosequence of 24 red spruce (Picea rubens Sarg.) dominated stands in Nova Scotia, Canada, were compared against predictions from the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3). Regression analysis of the observed versus simulated total ecosystem C stocks indicates the model's predictions accounted for 81.1% of the variation in the observed biomass data and for 63.2% of the variation in total ecosystem C data; however, the simultaneous F-test for bias was significant. Discrepancy between the observed and simulated total ecosystem C data was primarily caused by differences in dead organic matter C pool estimates, with the model consistently predicting higher soil C throughout stand development. Changes to model parameters were not warranted however, as the field data measured only a portion of the mineral soil profile represented in the model.

Clear-cut and partial-cut harvesting scenarios for red spruce stands were simulated to examine the impacts of clear-cut and partial-cut harvesting on C stocks. Total ecosystem C increased in the partial-cut stand throughout the 240-year simulation from 308.9 to 327.3 Mg C ha−1, while it decreased in the clear-cut stand to 305.8 Mg C ha−1. Enhanced C sequestration in the partial-cut stand was a consequence of the residual standing biomass providing a continuous source of litterfall and reducing decomposition rates of the forest floor. Choice of harvest system clearly affects forest ecosystem C stocks, but also affects the amount of C removed from forests to meet society's needs. Over the period of the simulation, partial cutting provided 115.6 Mg C ha−1 of merchantable timber, while clear-cutting provided 132.4 Mg C ha−1. Strategies aimed at using forest management to mitigate atmospheric C increases need to assess both the direct impacts on the forest ecosystem and the indirect impacts through product and energy substitution associated with the use and storage of harvested biomass.  相似文献   


17.
An extremely fragmented timber supply, high harvesting costs, low profitability, high subsidies and insufficient competitiveness characterise forest enterprises in Switzerland. In a case study using a forest district in the state of Solothurn as an example, it was sought to identify strengths and weaknesses of wood production and to formulate possible improvement opportunities. The results indicate that there is considerable potential for industry rationalisation. The greatest handicaps are the small sized forest holdings, excessive numbers of staff, insufficient use of modern harvesting technology and costly business administration. The most eminent of the proposed improvement measures are those which aim to increase concentration of timber supplies and reduce production costs. These include greater centralising of timber sales as well as planning and steering of production, making full use of modern harvesting systems, reducing transaction costs, supporting administration, planning and steering of wood production with modern information technology and reducing input on stand tending. In principle, amelioration can be best achieved by close cooperation with neighbours or even merger of enterprises. Consequently, there is a need for related business tasks to be combined in functions. The paramount prerequisite for success is the willingness and readiness of all affected stakeholders to make changes. The situation described is typical for Swiss forestry and the proposed solutions could well be used as models for a wide range of Swiss forest districts.  相似文献   

18.
Global climate change poses new opportunities and challenges for forestry development, and therefore developing multiple-purpose forestry is an important measure to strengthen forestry response to climate change. At present, plantation in China ranks the world first in area, but with relatively low productivity. Constantly expanding forest area and improving forest management for enhancing multiple functions and purposes of plantations are the key measures to upgrade plantation capacity to mitigate and adap...  相似文献   

19.
Sasaki  Nophea; Kim  Sophanarith 《Forestry》2009,82(1):105-115
The role of forests in absorbing atmospheric carbon has beenrecognized under the Kyoto Protocol, which allows signatorycountries to use forests as a mitigation option. Although severalstudies have estimated carbon stock changes in Japanese forests,most only estimate changes up to 1995 or ignore carbon stockchanges in natural forests. This study is the first attemptto estimate carbon stock changes in Japanese forests from 1966to 2012, to coincide with the final year of the Kyoto Protocol'sfirst commitment period. Forest area and growing stock datawere analysed. Then, two models for predicting the change inforest area and growing stock were developed. Results showedthat most natural forest loss resulted from conversion to plantationforest. The total above-ground and below-ground carbon stockin Japanese forests has been estimated to have increased from1114.8 TgC in 1966 to 2076.0 TgC in 2012, representing an increaseof 20.9 TgC year-1 over the same period. During the first commitmentperiod of the Kyoto Protocol (2008–2012), annual carbonsinks were estimated at 20.1 TgC, of which 76.9 per cent weresequestered in plantation forests. Of the 20.1 TgC year-1, eligiblecarbon sinks are estimated at 10.2 TgC or 78.7 per cent of themaximum or capped amount as allowed under the Marrakesh Accord.Although further effort is needed so that the capped amountof 13 TgC year-1 could be achieved, this study suggests thatcarbon sinks through forest management could be used to offsetindustrial carbon emissions.  相似文献   

20.
林业运输线路优化是林业物流和林业企业木材生产流程中重要部分。以吉林省汪清林区为研究区,基于网络最短路径模型和GIS、RS技术以及伐区、集材和运材等环节约束条件,构建伐区运输线路优化模型,确定伐区木材运输最优线路,并对选取的运输线路进行综合实证分析。  相似文献   

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