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以通化县林业局三棚林场为例,论述了红松采种林基地建设的有关技术设计方案及经营管理措施。进而阐述了保护和开发好吉林省东部地区红松优良种质基因资源,对恢复吉林省东部森林生态系统,改善生态环境,建设生态省,实现可持续发展的战略规划具有重大意义。 相似文献
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提出发挥森林资源管理作用,提高林地生产力的重要性和紧迫性,进一步完善森林资源监测体系,才能发挥出森林经营方案在科学组织林业生产中的作用。 相似文献
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Harri Kilpeläinen Olli Salminen Kari Härkönen Jari Miina 《Scandinavian Journal of Forest Research》2018,33(4):378-386
In many areas, picking wild berries constitutes an important forest commodity offering food, recreational services, and revenues. Intensified forest management has negatively affected bilberry yields. In this study, regional-level scenario analyses were conducted to investigate the effects of four approaches to the inclusion of bilberry yields on the economics, management, and resulting forest structures in North Karelia. The current approach ignoring bilberries resulted in decreasing bilberry yields and increasing younger forests. When bilberries were valued at market price (1.72?€?kg?1), bilberry yields still decreased despite the fact that forest management were slightly modified to favour bilberry. Adding non-declining sustainability constraints to bilberry yields resulted in a slightly lower total net present value of timber and bilberry since forest management favoured longer rotation lengths, which increased bilberry yields. Similar effects occurred when the bilberry price was tripled to include the implicit ecosystem benefits of bilberries. When forests were managed only for bilberries (timber zero-priced), bilberry yields started to increase immediately resulting in 1.5-fold difference in 50 years as compared to timber only scenario. In conclusion, managing forests for both timber and bilberry production has rather minor effects on economics, but it can have clear positive effect on bilberry yields. 相似文献
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R. Moore 《Agroforestry Systems》1992,20(1-2):167-186
About 21% of agricultural land in Australia is seriously degraded by salination and wind erosion. Trees can contribute to overcoming these problems. There is potential for trees to also produce wood, thereby diversifying farmers' incomes, reducing Australia's bill for importing wood and increasing exports of wood products. Even though many of these multiple purpose plantings would be widely scattered and growth rates low in some regions, Australian farmers should have a comparative advantage in wood production because trees also provide substantial landcare and agricultural productivity benefits. The establishment of new industries based on wood from farmland requires leadership from Government, planning at national, regional and local levels, and innovative techniques to finance planting. Removal os taxation disincentives for wood producers and the introduction of legislation to allow profit à prendre contracts would provide more favourable conditions for investment. 相似文献
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T. Heinonen T. Pukkala V.-P. Ikonen H. Peltola A. Venlinen S. Dupont 《Forest Ecology and Management》2009,258(7):1567-1577
Wind is the major abiotic risk factor in Finnish forests. Therefore, tools that help managers to assess the risk of wind damage are required. This study developed simple regression models for predicting the critical wind speed needed to uproot Scots pine, Norway spruce and birch trees at the stand edges in Finnish conditions, using the characteristics of the retained forest both downwind and upwind stands as predictors. Using information on the prevailing wind conditions in the region, the critical wind speeds were converted into probabilities of wind damage, from which a mean risk index was calculated. The mean risk index was used as an objective variable in heuristic optimisation. The results of minimizing the mean risk index were compared to other objective variables such as minimal height differences between adjacent stands. The residuals of the regression models of critical wind speeds were small, especially in Scots pine and birch. Increasing tree height of the downwind stand or area of the upwind stand (gap size) decreased the critical wind speed regardless of tree species, whereas increases in the dbh/height ratio of the downwind stand increased the critical wind speed. The shelter effect of upwind stand height was stronger in Norway spruce than in other tree species, whereas the effect of tree height of the downwind stand was larger in Scots pine and birch. Minimization of the mean risk of wind damage within forest landscapes led to smooth and non-fragmented landscape structures in terms of tree height. Incorporating even-flow constraints into the planning model led to a slight increase in the mean risk of wind damage. Of the surrogate methods for risk assessment minimization of height differences between adjacent stands performed well but not equally well as minimization of the mean risk index. 相似文献
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森林资源可持续经营探讨 总被引:2,自引:0,他引:2
随着改革开放的不断深入,人民生活水平的不断提高,整个社会对环境的要求越来越高,保持森林资源可持续经营势在必行。文章通过分析森林资源分类经营,森林资源管理和保持等方面存在的问题,阐述了如何实现森林实现森林资源可持续经营的策略。 相似文献
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ZHANG Gui-lian WANG Kai-yun LIU Xin-wei PENG Shao-lin 《林业研究》2006,17(4):305-311
Introduction Masson pine (Pinus massoniana) is important both economically and ecologically in subtropical mountainous areas in China, and it is vital not only as an important source of commercially harvested timber and charcoal fuel, but also as a pionee… 相似文献
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Christopher Baraloto Eric Marcon François Morneau Sandrine Pavoine Jean-Christophe Roggy 《Annals of Forest Science》2010,67(3):303-303
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An integrated assessment approach to optimal forest bioenergy production for young Scots pine stands
《Forest Ecosystems》2015,(3)
Background: Bioenergy is re-shaping opportunities and imperatives of forest management. This study demonstrates,through a case study in Scots pine(Pinus sylvestris L.), how forest bioenergy policies affect stand management strategies.Methods: Optimization studies were examined for 15 Scots pine stands of different initial stand densities, site types, and temperature sum regions in Finland. Stand development was model ed using the Pipe Qual stand simulator coupled with the simulation-optimization tool Opti For Bioenergy to assess three forest bioenergy policies on energy wood harvest from early thinnings.Results: The optimal solutions maximizing bare land value indicate that conventional forest management regimes remain optimal for sparse stands. Energy harvests occurred only when profitable, led to lower financial returns. A forest bioenergy policy which included compulsory energy wood harvesting was optimal for denser stands. At a higher interest rate(4 %), increasing energy wood price postponed energy wood harvesting. In addition, our results show that early thinning somewhat reduced wood quality for stands in fertile sites. For less fertile sites, the changes were insignificant.Conclusions: A constraint of profitable energy wood harvest is not rational. It is optimal to carry out the first thinning with a flexible forest bioenergy policy depending on stand density. 相似文献
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The species composition of wood-inhabiting fungi (polypores and corticoids) was investigated on 1138 spruce logs and 992 pine logs in 90 managed and 34 natural or near-natural spruce and pine forests in SE Norway.Altogether, the study included 290 species of wood-inhabiting fungi. Comparisons of logs with similar properties (standardized tree species, decay class, dimension class) in natural and managed forests showed a significant reduction in species number per log in managed spruce forests, but not in managed pine forests. The species number per log in managed spruce forests was 10-55% lower than on logs from natural spruce forests. The reduction was strongest on logs of large dimensions. A comparison of 200-400 spruce logs from natural and managed forests showed a 25% reduction in species richness corresponding to a conservative loss of ca. 40 species on a regional scale.A closer inspection revealed that species confined to medium and very decayed spruce logs were disfavored in managed forests, whereas species on early decay classes and decay generalists were unaffected. Similarly, species preferring large spruce logs were disfavored in managed forests. Forest management had strongest impact on low-frequent species in the spruce forests (more than 50% reduction), whereas common species were modestly affected. Corticoid fungi were more adversely affected than polypore fungi.These results indicate that wood-decaying fungi in pine forests are more adapted to forest disturbances than spruce-associated species. Management measures securing a continuous supply of dead wood are more important in spruce forests than in pine forests. 相似文献
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The achievement of sustainable forest management requires the incorporation of risk and uncertainty into long-term planning. Climatic change will have significant impacts on natural disturbances, species and ecosystems, particularly on landscapes influenced by forest management. Understanding where vulnerabilities lie is important in managing the risks associated directly or indirectly with climatic change. The vulnerability of landscapes to natural disturbances, the resilience of ecosystems and distribution of species are all important components that need to be considered when undertaking forest planning, but climatic change is rarely factored into such planning. In this study, the vulnerability of fire potential, fire regimes, ecosystems and species to climatic change was modelled for a 145,000 ha landscape in the south-central interior of British Columbia, Canada. The results from these analyses were used to guide forest zoning, using the triad zoning framework, and for the development of a “climate-smart” management framework. The use of climate-smart management is advocated as a decision-making framework for managing forested landscapes based on an understanding of landscape vulnerability to future climatic change. From this understanding, the maintenance of ecosystem health and vitality could be achieved. 相似文献
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The potential for traditional and local ecological knowledge to contribute to biodiversity conservation has been widely recognized, but the actual application of this knowledge to biodiversity conservation is not easy. This paper synthesizes literature about traditional and local ecological knowledge and forest management in the Pacific Northwest to evaluate what is needed to accomplish this goal. We address three topics: (1) views and values people have relating to biodiversity; (2) the resource use and management practices of local forest users, and their effects on biodiversity; (3) models for integrating traditional and local ecological knowledge into biodiversity conservation on public and private lands. We focus on the ecological knowledge of forest users belonging to three groups who inhabit the region: American Indians, family forest owners, and commercial nontimber forest product harvesters. 相似文献
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Xiao CW Yuste JC Janssens IA Roskams P Nachtergale L Carrara A Sanchez BY Ceulemans R 《Tree physiology》2003,23(8):505-516
We estimated above- and belowground biomass and net primary production (NPP) of a 73-year-old Scots pine (Pinus sylvestris L.) forest stand in the Belgian Campine region. Total biomass for the stand was 176 Mg ha(-1), of which 74.4% was found in stems. The root system contained 12.6% of total biomass, most of it in coarse roots (> 5 mm). Fine roots (< 5 mm) comprised only about 1.7% of total biomass, and more than 50% of fine root biomass was retrieved in the litter layer and the upper 15 cm of the mineral soil. The ratio of belowground biomass to aboveground biomass was 0.14, which is lower than that of other Scots pine forests and other coniferous forests. Between 1995 and 2001, mean annual NPP was 11.2 Mg ha(-1) year(-1), of which 68.7% was allocated to aboveground compartments. Stems, needles and cones made relatively high contributions to total NPP compared with branches. However, branch NPP was possibly underestimated because litterfall of big branches was neglected. The proportion of total NPP in belowground components was 31.3%. Coarse root NPP (2% of total) was low compared with its biomass. Fine root NPP was 3.3 Mg ha(-1) year(-1), representing about 29.5% of total NPP; however, the estimate of fine root NPP is much more uncertain than NPP of aboveground compartments. The ratio NPP/GPP (gross primary production) was 0.32, which was low compared with other coniferous forests. 相似文献
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Integrating regional climate change into allometric equations for estimating tree aboveground biomass of Masson pine in China 总被引:1,自引:0,他引:1
Liyong Fu Xiangdong Lei Zongda Hu Weisheng Zeng Shouzheng Tang Peter Marshall Lin Cao Xinyu Song Li Yu Jingjing Liang 《Annals of Forest Science》2017,74(2):42
Key message
A climate-sensitive aboveground biomass (AGB) equation, in combination with nonlinear mixed-effects modeling and dummy variable approach, was developed to examine how climate change may affect the allometric relationships between tree diameter and biomass. We showed that such changes in allometry need to be taken into account for estimating tree AGB in Masson pine.Context
As a native species and being widely distributed in subtropical China, Masson pine (Pinus massoniana Lamb.) forests play a pivotal role in maintaining forest ecosystem functions and mitigation of carbon concentration increase at the atmosphere. Traditional biomass allometric equations do not account for a potential effect of climate on the diameter–biomass relationships. The amplitude of such an effect remains poorly documented.Aims
We presented a novel method for detecting the long-term (2041–2080) effects of climate change on the diameter–biomass relationships and the potential consequences for long-term changes of biomass accumulation for Masson pine.Methods
Our approach was based on a climate-sensitive AGB model developed using a combined nonlinear mixed-effects model and dummy variable approach. Various climate-related variables were evaluated for their contributions to model improvement. Heteroscedasticity was accounted for by three residual variance functions: exponential function, power function, and constant plus function.Results
The results showed that diameter at breast height, together with the long-term average of growing season temperature, total growing season precipitation, mean temperature of wettest quarter, and precipitation of wettest quarter, had significant effects on values of AGB. Excessive rain during the growing season and high mean temperature in the wettest quarter reduced the AGB, while a warm growing season and abundant precipitation in the wettest quarter increased the AGB.Conclusion
Climate change significantly affected the allometric scale of biomass equation. The new climate-sensitive allometric model developed in this study may improve biomass predictions compared with the traditional model without climate effects. Our findings suggested that the AGB of Masson pine trees with the same diameter at breast height under three climate scenarios including representative concentration pathway (RCP) 2.6, RCP 4.5, and RCP 8.5 in the future period 2041–2080 would increase by 24.8 ± 32.7% (mean ± standard deviation), 27.0 ± 33.4%, and 27.7 ± 33.8% compared with the constant climate (1950–2000), respectively. As a consequence, we may expect a significant regional variability and uncertainty in biomass estimates under climate change.17.
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Jorge Aldea Fernando Martínez-Peña Luis Diaz-Balteiro 《European Journal of Forest Research》2012,131(6):1991-2003
Some non-timber forestry products, such as mushrooms, have not typically been included in forest management plans, creating a scenario whereby timber production is the main objective and fungal resources are an afterthought. However, in certain forests, wild mushrooms reach a significant level of production. This paper researches a strategic forest management plan that would include the production of both timber and mushrooms as principal objectives while still adhering to constraints normally considered within forest management. A case study is provided featuring two main groups of edible wild mushrooms, where the two aforementioned objectives have been optimised individually. Lacking a satisfactory solution for the decision-maker, a model based on multi-criteria decision analysis (compromise programming) has been constructed to yield more attractive solutions. Information regarding mushrooms is based on the actual amount collected in the forest and not on potential production. Measured in monetary terms, mushroom production can be easily compared with timber production. Income associated with mushroom production is equal to approximately 20 % of that generated by timber throughout the planning horizon when final inventory and regulation constraints are imposed. 相似文献
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