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1.
Timber production possibilities of the Norwegian forest area and measures for a sustainable forestry
《Forest Policy and Economics》2002,4(3):187-200
This paper presents long-range forest management analyses with the objective of mapping consequences for the timber production potential when forest management treatments are changed in an environmentally oriented direction. Sample plots from the National Forest Inventory, covering the entire productive forest area in Norway, were aggregated into 10000 treatment units. Management strategies maximising the net present value of the forest-land, with certain environmentally oriented constraints, were analysed. The following environmentally oriented constraints were considered: (i) areas of current old forest set aside, either proportionally or cost-efficiently, for permanent preservation, (ii) minimum target levels for area covered by old forest through time, (iii) retention of trees at final felling, and (iv) restricted management for border zone areas. With a real rate of discount of 2.5%, and all the constraints imposed simultaneously, the annual harvest potential was reduced by 30% for the first 10-year period, while the net present value was reduced by 21.5%. The results further demonstrated significant efficiency gains of letting the preservation of old forest be allocated cost-efficiently, compared with a strategy of setting aside an equal portion on all eligible areas. 相似文献
2.
《Forest Policy and Economics》2008,10(3):98-107
The objectives of nature conservation can often only be realised by changing forest management regimes. Thus far, mainly institutional regulations have been used to achieve these goals. However, in Germany there is strong political interest in encouraging contract-based forest management whereby forest owners receive financial compensation for losses when changing over forest management regime. Such compensation is commonly paid in the German agricultural sector but is absent in forestry.When managing forests for social convenience, forest enterprises are faced with financial losses. With regard to practical experience in forestry there is a considerable lack of information about the economic consequences.To estimate the losses related to changes in silvicultural treatment, a calculation scheme based on the annuity method has been developed and figures have been calculated for different tree species and age classes. The annual timber production value determined per ha and year is documented in tables and, as shown by examples, could be applied to evaluate typical changes in forest management such as the renunciation of forest production, change of tree species, premature harvest and the preservation of mature stands.Standardised annual timber production values for different tree species, yield classes, management schemes etc. can be helpful to estimate the financial losses for forest-land owners when changing the management strategy. These financial losses can also be interpreted as the minimum price which has to be offered to forest land owners when a contract-based forest management is striven for by the government. 相似文献
3.
Pascal Côté Rebecca Tittler Christian Messier Daniel D. Kneeshaw Andrew Fall Marie-Josée Fortin 《Forest Ecology and Management》2010
Forest management has been criticised in the last 20 years for its negative impact on the native species, structures and functions of the forest. Of many possible alternatives proposed to minimize these effects, the functional zoning (or TRIAD) approach is gaining popularity in North America. The goal of this approach is to minimize the negative environmental impacts of forestry while maintain timber supply by dividing the forest into three broad land-use zones: (1) conservation, (2) ecosystem management, and (3) wood production. In this study, we used a spatially explicit landscape model to simulate the effects of fire and six different forest management scenarios on a boreal mixedwood forest management unit in central Quebec. The management scenarios examined included the current practices scenario, a scenario proposed by the provincial government, and four TRIAD scenarios varying in the amount of forest allocated to each of the three zones. For each scenario, we examined the harvest volume, percentage old-growth forest or old forest managed to favour old-growth attributes, and effective mesh size of forest patches by 20-year age classes. With more area set aside for conservation and high-retention partial cut harvesting techniques designed to maintain the attributes of old-growth stands, all TRIAD scenarios resulted in higher percentages of stands with old-growth attributes than the current practices scenario and the government proposed scenario, and two of the four TRIAD scenarios also resulted in higher harvest volume over the long term. All forest management scenarios resulted in significantly lower effective mesh size than the fire-only scenario, but this difference was not as pronounced for the four TRIAD scenarios as for the current practice and government proposed scenarios. We conclude that the TRIAD approach has the potential to minimize some of the negative impacts of forestry on the landscape, while maintaining timber supply over the long term. 相似文献
4.
Anu Korosuo Per Sandström Karin Öhman Ljusk Ola Eriksson 《Scandinavian Journal of Forest Research》2014,29(7):234-251
In northern Sweden, the forests are used simultaneously for both timber production and reindeer husbandry. During the winter months, lichen is the most important fodder for reindeer. Forest management operations are generally considered having a negative impact on reindeer husbandry as harvesting and dense stands remove or obscure the ground lichen cover. In this study, we simulate three different scenarios for forest management, differing in the intensity and types of harvest operations. The resulting 100-year scenarios are analyzed with respect to their estimated suitability for providing reindeer pasture areas. Suitability is determined by vegetation type, stand density and stand height. The results indicate that the current trend of a decrease in lichen area will continue if existing forestry practice prevails. Implementing continuous cover forestry as a management alternative and carrying out precommercial thinning could halt the decrease in reindeer pasture area and even lead to a future increase in pasture area, with losses of approximately 5% in the net present value of forestry. 相似文献
5.
Carbon sinks constitute an important element within the complex phenomenon of global climate change,and forest ecosystems are important global carbon sinks.The Natural Forest Protection Program(NFPP) is an ecological program in China that was established after catastrophic flooding in the country in 1998.The goals of the NFPP are to curb the deterioration of the ecological environment,strengthen the protection and restoration of habitat to increase biodiversity,and rehabilitate natural forests to support sustainable development in forest regions.This study looked at changes in carbon sequestration in a forested area of northeast China after the inception of the NFPP.The program divides China's natural forests into three classes—commercial and two types of noneconomic forests—that are subject to management regimes prescribing varying levels of timber harvest,afforestation,and reforestation.During the 18-year period from 1998 to 2015,the total amount of carbon sequestration increased at an average annual rate of 0.04 MT C.This trend reflects a transformation of forest management practices after implementation of the NFPP that resulted in prohibited and/or restricted logging and tighter regulation of allowable harvest levels for specific areas.In documenting this trend,guidelines for more effective implementation of forestry programs such as the NFPP in other countries in the future are also suggested. 相似文献
6.
Kihachiro Ohba 《Forest Ecology and Management》1983,6(3):245-262
Forestry practice differs from agricultural crops practice owing to the huge size of trees, their longevity and the variety of uncontrollable conditions under which they grow. Even with intensive forest management, the actual effects of investment of labour and materials in the forest seem to be fairly small because of the size of the forest and the long harvest rotation. Since we expect to produce both a higher quantity and a higher quality of timber with intensive forestry, it is very important to have adequate counter-measures to the fatal or destructive factors which affect forest establishment and growth. In Japan, in the field of forest tree breeding, we are making maps as information sources for decision making, in which iso-lines show the degrees of damage due to fatal factors such as pests and diseases. If there is more than one fatal factor overlapping in an area, it might be difficult to grow forests for commercial purposes. We have to decide how to use the forest land in these areas, or how to take counter-measures such as tending, chemical control, genetic improvement or even a change in the tree species. As forestry has a long harvest rotation, it is necessary to have ‘a quality control system’ in management, in which a follow-up assessment of planting materials, tending techniques in combination with site conditions, and fatal factors will be made. In this situation, forest tree improvement (breeding) seems to be of prime importance in intensive forest management in the future. 相似文献
7.
Uneven-sized forestry is gradually gaining popularity and acceptability also in the Nordic countries. This is because of the willingness of the public and some forest owners to avoid clear-fellings and pursue more near-nature forest structures. It has also been realized that the profitability of uneven-sized forestry may be competitive with even-aged forestry. In Finland, management of uneven-sized stands is hampered by the lack of information about the dynamics of such stands, and about the yield and profitability of uneven-sized forestry. This study developed models which allow managers to simulate the growth and yield of uneven-sized stands in Finland, making it possible to predict the yield and analyze the sustainability of different management options. The model set consists of individual-tree diameter increment, height and survival models, and a model for ingrowth. The modeling data consisted of two long-term field experiments of uneven-sized forest management, a set of temporary sample plots measured earlier for growth modeling purposes, and the sample plots of the third National Forest Inventory of Finland. The application area of the models covers all growing sites, all main tree species, and the whole surface area of Finland. According to the models, the sustainable harvest of a fertile (Oxalis-Myrtillus site) uneven-sized Norway spruce forest varies between 5.5 and 7 m3 ha−1 a−1 in Central Finland, depending on the length of the cutting cycle, stand density, and shape of the diameter distribution. It is profitable to harvest large diameter classes more heavily than small ones. Due to the large amount of data the models for diameter increment are highly significant and reliably show the growth level of trees in uneven-sized stands. The weakest models are the ingrowth models, which are based on a clearly smaller data set than the other models. 相似文献
8.
林权抵押贷款是农村金融体系的重要组成部分,在支持林业发展、推动乡村振兴中发挥着重要作用。文中从交易费用视角探讨林权抵押贷款的发展演变规律发现:发展演变的本质是对森林资源价值属性的不断认识与确认,发挥林地的财产功能;发展演变的动力是交易费用通过新的制度安排转化成外部利润,形成规模收益;发展演变是朝着降低交易费用的方向进行。由此提出如下建议:及时改善交易市场环境,鼓励多种市场主体参与贷款交易,不断设计和完善利益分配机制,创新符合林业普惠金融与林业规模化经营双重要求的信贷模式。 相似文献
9.
《Forest Ecology and Management》2007,238(1-3):167-174
Knowledge about the nutrient and carbon budgets in forest soils is essential to maintain sustainable production, but also in several environmental issues, such as acidification, eutrophication and climate change. The budgets are strongly influenced by atmospheric deposition as well as forestry. This study demonstrates how budget calculations for nitrogen (N), carbon (C) and base cations (BC) can be used as a basis for policy decisions on a regional level in Sweden.The study was based on existing nutrient and C budget calculations on a regional scale in Sweden. The nutrient budgets have been calculated for each square in a national 5 km × 5 km net by means of mass balances including deposition, harvest losses, leaching, weathering (BC) and fixation (N). Scenarios with different deposition and forestry intensity have been run and illustrated on maps. A simplified C budget has been estimated by multiplying the N accumulation with the C/N ratio in the organic layer, based on the assumption that the C/N ratio in the accumulating organic matter is equal to the ratio in the soil organic matter pool. The budget approaches differ from earlier budget studies since they involve regional high resolution data, combine deposition and forestry scenarios and integrate different environmental aspects.The results indicate that whole-tree harvesting will cause net losses of N and base cations in large parts of Sweden, which means that forestry will not be sustainable unless nutrients are added through compensatory fertilization. To prevent net losses following whole-tree harvesting, compensatory fertilization of base cations would be required in almost the whole country, whereas N fertilization would be needed mainly in the northern half of Sweden. The results further suggest that today's recommendations for N fertilization should be revised in southern Sweden by applying the southwest–northeast gradient of the N budget calculations. The C and N accumulation calculations show that C sequestration in Swedish forest soils is not an effective or sustainable way to decrease the net carbon dioxide emissions. A better way is to apply whole-tree harvesting and use the branches, tops and needles as biofuel replacing fossil fuels. This could reduce the present carbon dioxide emissions from fossil fuels substantially.The study shows that high resolution budget calculations that illuminate different aspects of sustainability in forest ecosystems are important tools for identifying problem areas, investigating different alternatives through scenario analyses and developing new policies. Cooperation with stakeholders increases the probability that the research will be useful. 相似文献
10.
以登封国有林场为试验对象,开发了国有林场森林资源信息管理系统,并得到应用。基本上实现了登封国有林场森林资源管理的信息化,为森林资源的科学管理和决策,以及可持续发展提供了技术支持。 相似文献
11.
森林资源调查是建立或更新森林经营方案、制定森林采伐限额、进行林业工程规划设计和森林资源管理的基础,也是制定区域国民经济发展规划和林业发展规划、实行森林生态效益补偿和森林资源资产化管理、指导和规范森林科学经营的重要依据。近年来,以微电脑为基础的3S（RS、GIS、GPS）集成技术进行的高精度面积测量和GIS自动成图,为提高面积测量精度和不同地类准确定位提供了重要技术保障。星源通掌上森林资源调查仪是以3s集成技术为基础研制的森林资源调查仪器,为检验其测量精度,在汪清林业局不同林地选择地形明显、最易勾绘的10个小班进行精度检验,小班的勾绘面积最小为1．34hm^2,最大为35．80m^2。结果表明,测量精度最低为98．0％,最高为99．2％,平均为98．71％;星源通掌上森林资源调查仪可广泛应用于森林资源调查、伐区调查设计、造林地验收、林火损失评估、征占用林地调查等多个方面。 相似文献
12.
龙陵县林业可持续发展战略思考 总被引：2，自引：1，他引：1
龙陵县具备自然条件优越、森林资源丰富、林业产业初具规模、劳动力资源丰富等林业可持续发展的优势,但林业发展中仍面临着林业产业化水平低、综合管理水平低、森林资源监测和管理薄弱等困难和问题.藉此,提出以各种重点林业工程建设为基础进行"开源节流"、建立和完善相关的政策法规、提高森林经营管理水平、加强基础设施和队伍建设、优化林业产业结构等林业可持续发展战略. 相似文献
13.
实行森林分类经营需要处理好的六个关系 总被引：1，自引：0，他引：1
林业分类经营改革是实行林业可持续发展的关键，为了推进林业分类经营改革，笔者以六个方面分析阐述了在分类经营改革中需处理好的六个关系。即：分类经营与综合经营的关系；分类经营与市场经济的关系；分类经营与传统林业的关系；商品林与公益林的关系；分类经营与林业企业转机建制的关系；分类经营与可持续发展的关系。 相似文献
14.
《Forest Ecology and Management》2006,236(1):113-126
Forest management shapes landscape patterns, and these patterns often differ significantly from those typical for natural disturbance regimes. This may affect wildlife habitat and other aspects of ecosystem function. Our objective was to examine the effects of different forest management decisions on landscape pattern in a fire adapted ecosystem. We used a factorial design experiment in LANDIS (a forest landscape simulation model) to test the effects of: (a) cut unit size, (b) minimum harvest age and (c) target species for management. Our study area was the Pine Barrens of northwest Wisconsin, an area where fire suppression has caused a lack of large open areas important for wildlife. Our results show that all three management choices under investigation (cut unit size, minimum harvest age and target species for management) have strong effects on forest composition and landscape patterns. Cut unit size is the most important factor influencing landscape pattern, followed by target species for management (either jack pine or red pine) and then minimum harvest age. Open areas are more abundant, and their average size is larger, when cut units are larger, target species is jack pine, and minimum harvest age is lower. Such information can assist forest managers to relate stand level management decision to landscape patterns. 相似文献
15.
林地可持续经芝模式评价的研究 总被引：2，自引：0，他引：2
林业可持续发展是目前国内外讲座的一个热点，林地可持续经营是林业可持续发展的一个重要基础。本文结合实例探讨了林地可持续经芝投资项目评价的特点、过程与方法，并据此筛选出杉木多代萌芽林地可持续经营优化模式－杉阔轮栽模式。 相似文献
16.
本文根据湖南省天然林资源的现状,结合保护实施方案,对湖南天然林保护与林业可持续发展进行了探讨,并提出了初步实施措施. 相似文献
17.
Community forestry is an emerging success model of state–community partnership for forest management and poverty reduction. Bhutan's initial experience of forest management by user group is promising, but merits further study on how community forests have experienced with harvesting and income generation consistent with national forest policy. This study quantifies whether community forestry contribute to household income with equitable products and income distribution and gender inclusive participation; and community forests are managed applying the principles of sustainable harvest without compromising regeneration and productivity. We applied a combination of social and ecological methods using household interview and forest sampling plots. Our findings revealed that community forestry contributes to household income through harvesting and marketing of large trees, and non-wood forest products where markets are accessible. Household income, however, vary widely between rich and poor households with former capitalizing on commercial and latter on subsistence products. Timber harvesting is consistent with the principles of sustainable harvest without altering species composition, regeneration and productivity. To narrow income inequality, pro-poor approach to community forestry needs to target poor households with income diversification activities and market accessibility. The promising results are context-driven and warrant consolidation from other community forests experiencing harvest in Bhutan. 相似文献
18.
19.
《Forest Policy and Economics》2008,10(5):326-335
The paper examines the economic impacts of sustainable forest management (SFM) policies in Canada. Specifically, the marginal costs (MC) of old-growth preservation in an even-aged boreal forest in northeastern Ontario are examined under the condition that forest managers need to achieve multiple objectives for SFM. Furthermore, the trade-offs of old-growth preservation are estimated, allowing the levels of three specific SFM objectives to vary, namely, providing a consistent supply of timber in each period, meeting terminal volume targets at the end of the planning horizon, and maintaining a desired age structure of the forest. MCs are higher for harvesting regimes constrained by SFM objectives compared with that in which only profit maximization is considered. We observed that MCs for these three scenarios varied more when the area allotted for old-growth preservation is small. When the area of protected old-growth forest reaches about 66% of the maximum possible, the MCs are almost the same. All MCs are iso-elastic. The even-flow volume per period has the highest marginal cost among the three cases. If managers choose to provide terminal volume that is greater than or equal to the initial volume, instead of a lesser terminal volume, then old-growth forest can be preserved at no extra cost. The study emphasizes the need for integrated and simultaneous achievement of complementary goals of SFM for better economic return and minimization of the negative economic impact of SFM on the forestry sector. 相似文献
20.
上杭县林业发展潜力和可持续经营分析 总被引：1，自引：0，他引：1
根据森林和林业资源消长的客观规律,遵循“法正林”概念和经营模式,运用林木生长和收获模型研究结果,采用动态比较的方法,分析上杭县的林业资源结构及其缺陷,研究并提出了分类指导的经营策略。分析表明,通过科学规划和经营,县域用材林林分在实施分类经营的前提下,可以适度缩减面积,保留生长(立地)类型良好的林分实施集约化经营,在10 a经营期内,可以增加2倍的采伐量,林木蓄积增长73%。同时可以促进竹林、经济林、薪材林等资源的增长,促进林区生产的多样化,实现林业生产、林区经济的协调、可持续发展。 相似文献