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1.
Forest bioenergy is an alternative to fossil energy.Although forest bioenergy is of great value to ease energy supply,there is still a strong call for the research of what impact forest bioenergy plantation will exert on environment if under large scale development.By discussing the resource potential and development status of forest bioenergy,the paper attempts to explore the potential impact of forest bioenergy on environment and give some recommendations to mitigate and even avoid negative impact.  相似文献   

2.
γ-戊内酯是以木质纤维素生物质为原料制备的一种潜力巨大的平台化合物,它既可转化为高密度燃料、相关高分子材料以及其他高价值化学品,也可作为绿色溶剂促进木质生物质向其他高值方向转化。在化石能源日益紧俏、环境问题日益严重的今天,对γ-戊内酯进行深入研究显得尤为重要。但在实际生产中,仍存在产量低、除杂难等经济环保类问题需要解决。基于γ-戊内酯研究的最新进展,从γ-戊内酯的制备与应用两方面进行了论述,综述了生物质催化生产γ-戊内酯的研究进展,说明不同底物生产γ-戊内酯的理论基础与优缺点,并以贵金属和非贵金属催化剂为界,分类讨论了多种用于合成γ-戊内酯的催化剂。最后,结合γ-戊内酯在纤维素生物质转化应用方面的进展情况,探索了γ-戊内酯与其他相关有机物之间的制备关系,为γ-戊内酯的进一步开发利用提供了思路。  相似文献   

3.
Abstract

A partial equilibrium forest sector model which is augmented to include bioenergy was applied to project the use of bioenergy based on forest fuels and forest industry by-products in Norway for three different scenarios of the future prices of electricity and oil. The impacts on forestry and forest industries of the different energy price scenarios were also studied. The advantage of the suggested methodology is that it allows for assessments of the economic potential of bioenergy, taking into account the competition for raw materials, the specific heat demand of various regions, and interregional and international trade. Bioenergy will, according to this study, be fairly competitive in some market segments with the current price levels of electricity and oil, and only a minor increase (decrease) in energy (roundwood) prices would release substantially increased bioenergy production levels. Pulpwood prices of pine and non-coniferous species are projected to increase substantially when assuming increasing energy prices. Except for particleboard mills, production levels of forest industries appeared relatively insensitive to the energy price changes.  相似文献   

4.
Growing concerns over emissions of green-house gases causing climate change as well as energy security concerns have spurred the interest in bioenergy production pushed by EU targets to fulfil the goal of 20 per cent renewable energy in 2020, as well as the goal of 10 per cent renewable fuels in transport by 2020. Increased bioenergy production is also seen to have political and economic benefits for rural areas and farming regions in Europe and in the developing world. There are, however, conflicting views on the potential benefits of large scale bioenergy production, and recent debates have also drawn attention to a range of environmental and socio-economic issues that may arise in this respect. One of these challenges will be that of accommodating forest uses – including wood for energy, and resulting intensification of forest management – with biodiversity protection in order to meet EU policy goals. We note that the use of biomass and biofuels spans over several economic sector policy areas, which calls for assessing and integrating environmental concerns across forest, agriculture, energy and transport sectors.In this paper, we employ frame analysis to identify the arguments for promoting bioenergy and assess the potential policy conflicts in the relevant sectors, through the analytical lens of environmental policy integration. We conclude that while there is considerable leverage of environmental arguments in favour of bioenergy in the studied economic sectors, and potential synergies with other policy goals, environmental interest groups remain sceptical to just how bioenergy is currently being promoted. There is a highly polarised debate particularly relating to biofuel production. Based on our analysis, we discuss the potential for how those issues could be reconciled drawing on the frame conflict theory, distinguishing between policy disagreements and policy controversies.  相似文献   

5.
《林业研究》2021,32(1)
Tachi-branco(Tachigali vulgaris,L.F.Gomes da Silva H.C.Lima) is a leguminous tree species native to the Amazon rainforest that has drawn attention for its remarkably fast growth,a required trait for biomass/bioenergy plantations.In evaluations of biomass production and wood properties of T.vulgaris planted in homogeneous plantations at different spacings in the Amazonian state of Para,Brazil,biomass of 7-year-old trees was quantified for individual trees and the entire population.Wood was also sampled to assess properties relevant to bioenergy applications.The choice for spacing dimension for planting nonclonal T.vulgaris should consider whether the priority is greater productivity per tree,achieved with greater spacings(9.0 m~2 and 12.0 m~2),or productivity per area,achieved with closer spacings(6.0 m~2 and 7.5 m~2).Genetic variability of the T.vulgaris seed stand and/or high heritability of wood traits overcame the effect of different spacing on all morphological,physical,chemical and energetic properties of T.vulgaris wood.This species has moderate basic density when cultivated at spacings larger than 6 m~2 and net heating value above 7.95 MJ/kg,which is suitable for bioenergy purposes.The high variation in wood properties within tree spacing is strongly indicative of great potential for genetic breeding.The fast growth and the suitable moderate wood basic density confirm the outstanding potential of homogeneous plantations of T.vulgaris for providing wood for bioenergy.  相似文献   

6.
世界生物质能利用的现状和展望   总被引:16,自引:0,他引:16  
本文分析了世界生物质能利用的现状, 包括生物质能在世界能源消费结构中的地位, 近20年来在其开发利用方面的进展;根据世界能源发展的形势, 从开发利用潜力、环境保护、科学技术、政策法令等方面对生物质能的发展前景作了展望。  相似文献   

7.
论我国林业生物质能源林培育与发展   总被引:8,自引:0,他引:8  
能源危机和生态环境压力使世界发达国家纷纷转向发展和利用生物质能源,发展生物质能产业也是我国缓解能源供应压力和解决环境问题的途径之一。林业生物质能资源培育是一项系统工程,要从统筹资源培育和产业发展、进行现状及发展潜力调查评价、制定资源培育及产业发展总体规划、加强科技和加强优惠财税政策等方面做好工作;同时,处理好产业与生态、森林多目标培育的关系,处理好国家、企业和能源林经营者三者之间的关系,以促进我国林业生物质能产业健康快速发展。  相似文献   

8.
In the past the use of woody biomass for bioenergy was considered carbon neutral. However, this changed when analyses were made of cases of land use change or old growth forest logging for bioenergy purposes. These analyses showed a significant carbon debt that could take hundreds of years to be compensated by the substitution factor of the bioenergy.Currently, carbon debt analyses are often carried out: 1) at one hectare scale, or 2) against the hypothetical case of allowing the managed forest to grow to an old-growth state, or 3) in a comparison against short term policy goals. All three are not realistic for European forests. Here we analysed carbon debt and parity of realistically increased harvesting over large forest areas in Europe. We found that under such realistic cases, a carbon debt does not occur. i.e. the large scale average stocks in the forest are not reduced. What does occur is a parity compared to the baseline harvesting levels. The parity effect was eventually also compensated for. However it took long, especially if final fellings were increased for bioenergy; which is a rather hypothetical case. In case of increased thinnings, the parity equality was often reached within 80 years compared to burning coal. Removal of harvesting residues was often compensated within 1 decade. However, parity is a theoretical comparison against a higher baseline C stock in the forest. It is not certain that this higher stocking under the baseline will be sustained, because there is an increasing chance of natural disturbances. Thus the parity may be much shorter than analysed here.  相似文献   

9.
This study investigates the combined impact of carbon and bioenergy markets on upland oak dominated mixed hardwood forests in the Central Hardwood Forest Region (CHFR) of the United States. A modification of the Hartman model was used for the economic analysis of carbon sequestration and using wood-based biomass for bioenergy. A life-cycle assessment was used to determine the amount of carbon sequestered due to stand growth and emitted during harvesting and decay of wood products. Two scenarios were taken, one where additionality of carbon is considered and the other where it is not. Sensitivity analysis was done with the range of carbon and bioenergy prices. The results show that net carbon payments have more impact on land expectation value (LEV) when additionality is not considered; in contrast, bioenergy payments have more impact on LEV when additionality is considered. Carbon and bioenergy prices also influenced the amount of stand level supply of forest products and carbon in both scenarios. In general, sawtimber, wood bioenergy, and carbon supply increased with an increase in carbon prices, whereas, pulpwood supply decreased. With few exceptions at higher carbon prices, bioenergy supply decreased with the increase in wood bioenergy prices, showing a backward bending supply curve in both scenarios.  相似文献   

10.
Biochar is normally produced as a by-product of bioenergy. However, if biochar is produced as a co-product with bioenergy from sustainably managed forests and used for soil amendment, it could pro- vide a carbon neutral or even carbon negative solution for current envi- ronmental degradation problems. In this paper, we present a comprehen- sive review of biochar production as a co-product of bioenergy and its implications. We focus on biochar production with reference to biomass availability and sustainability and on bioehar utilization for its soil amendment and greenhouse gas emissions reduction properties. Past studies confirm that northwestern Ontario has a sustainable and sufficient supply of biomass feedstock that can be used to produce bioenergy, with biochar as a co-product that can replace fossil fuel consumption, increase soil productivity and sequester carbon in the long run. For the next step, we recommend that comprehensive life cycle assessment of bio- char-based bioenergy production, from raw material collection to bioehar application, with an extensive economic assessment is necessary for making this technology commercially viable in northwestern Ontario.  相似文献   

11.
咖啡产业是保山市的一大特色农业,大力发展咖啡产业是繁荣山区经济和实现乡村振兴的一条有效出路。从自然条件、政府政策、产业体系、市场前景等方面梳理保山咖啡产业发展现状。研究发现,虽然咖啡产业在保山市具有一定规模,成为特色产业,国内市场前景看好,但其存在易受国际期货价格波动影响,种植端粗放,加工端配套不足,销售端推广不成熟等问题。藉此,提出标准化生产,健全咖啡产业保险机制,提升管理和科技水平,强化品牌营销等策略。  相似文献   

12.
This article examines alternative forest harvesting regimes when ecosystem services in terms of water quality, biodiversity conservation and climate change mitigation are included in the analysis. The harvesting regimes are whole-tree harvesting with stump removal and conventional stem-only harvesting. The harvesting regimes are evaluated under two alternative climate policy contexts. The first alternative is a carbon neutral bioenergy policy, which assumes the carbon dioxide (CO2) neutrality of bioenergy and produces substitution benefits, as bioenergy replaces fossil fuels. The second alternative climate policy, a carbon non-neutral bioenergy policy, takes into account the fact that bioenergy causes carbon dioxide emissions, producing substitution costs, and that harvested woody biomass affects the ability of a forest to act as a carbon sink. We extend the traditional Faustmann (1849) rotation model to include nutrient load damage, biodiversity benefits, and climate impacts. The empirical analysis is based on Finnish data from a catchment experiment carried out on drained peatland forests. The empirical results show that under a carbon neutral bioenergy policy, whole-tree harvesting with stump removal produces the highest net social benefits. However, if a carbon non-neutral bioenergy policy is assumed, the net social benefits are greater under stem-only harvesting.  相似文献   

13.
国内外林业遥感应用研究概况与展望   总被引:3,自引:1,他引:2  
林业遥感技术不仅可以直接获取森林资源管理的数据,更能进一步揭示森林经营管理的生态影响。伴随合成孔径雷达、激光雷达、高光谱、热红外等高分辨率遥感设备和技术的快速发展,遥感在森林生物生态属性上的定量和定性测绘与监测方面发展十分迅速。文中重点介绍近几年国内外遥感在森林分布、组成、结构、动态和干扰、生产力监测上的应用概况,并从拓展林业遥感研究目标和维度、加大投入、提升平台建设能力和重点关注林业工程及数字林业规划等方面提出林业遥感未来的发展趋势。  相似文献   

14.
Current forest industries in south-western Australia are based on regrowth natural eucalypt forests and Pinus and Eucalyptus spp. plantations, and restricted to areas with >600 mm y?1 annual rainfall. Dryland farming systems have been developed across 20 million ha in a zone with 300–600 mm y?1 annual rainfall and a Mediterranean climate. This zone is beset with land degradation problems, such as salinity and wind erosion, and there has been considerable effort in the last three decades to develop reforestation options to stabilise the landscapes. Traditional forestry approaches using pulp wood or sawlog production in this zone have been limited by unfavourable economics driven by modest tree growth rates, large transport costs to processing and export facilities, and high labour costs. Given that salinity results from a disruption of the landscape water balance, reforestation has represented a major component in attempts to tackle the problem. Issues with reforestation include (1) obtaining sufficient scale of activity to impact watershed water balances, (2) obtaining a hydrological response without displacing farm production and rural communities and (3) gaining payment for non-forest benefits. This paper reviews the approaches that have been used to integrate trees into the dryland farming (300–600 mm y?1 annual rainfall) systems of south-western Australia, and have resulted in at least 113 286 ha of reforestation. These included both traditional (pine and eucalypt sawlogs) and new (sandalwood, biodiversity restoration and carbon mitigation through bioenergy and carbon sequestration) projects. Ongoing investment has centred on carbon sequestration as this represents one of the few profitable options for the management of dryland salinity in this region. Approaches developed in this region to encourage farmland reforestation will be applicable in other dryland regions, particularly with the interest in using the land-sector to meet climate mitigation targets.  相似文献   

15.
Increased forest biomass production for bioenergy will have various consequences for landscape scenery, depending on both the landscape features present and the character and intensity of the silvicultural and harvesting methods used. We review forest preference research carried out in Finland, Sweden and Norway, and discuss these findings in relation to bioenergy production in boreal forest ecosystems. Some production methods and related operations incur negative reactions among the public, e.g. stump harvesting, dense plantation, soil preparation, road construction, the use of non-native species, and partly also harvest of current non-productive forests. Positive visual effects of bioenergy production tend to be linked to harvesting methods such as tending, thinning, selective logging and residue harvesting that enhance both stand and landscape openness, and visual and physical accessibility. Relatively large differences in findings between studies underline the importance of local contextual knowledge about landscape values and how people use the particular landscape where different forms of bioenergy production will occur. This scientific knowledge may be used to formulate guiding principles for visual management of boreal forest bioenergy landscapes.  相似文献   

16.
对我国便携式林业机械参与国际标准化的思考   总被引:1,自引:1,他引:0  
我国便携式林业机械发展迅速,但生产企业参与国际标准制定的很少,试验设施严重短缺,自主产品份额低.发达国家便携式林业机械标准化的现状与发展是从专利和标准层面主控世界市场,将加工重心移向发展中国家,而把工作重心转向负责其国际标准的制定.文章提出了改善我国便携式林业机械国际标准化现状的建议.  相似文献   

17.
李海波 《绿色科技》2020,(4):39-40,42
基于海南省生活垃圾处理设施现状情况,综合分析了产生强度、设施规模化效应、运输距离等因素,对如何科学合理地在全省统筹规划布局生活垃圾焚烧厂进行了研究,提出了规划布局的方案和建议,为海南省今后生活垃圾焚烧厂的布局提供参考。  相似文献   

18.
现有生物质能转换利用技术综合评价   总被引:1,自引:0,他引:1  
本文介绍了生物质能转换利用的方法,对现有生物质能转换技术进行了比较,运用层次分析法从技术先进性、经济可行性和环境安全性三个方面对现有生物质能转换利用技术进行了综合评价,提出了生物质能转换利用技术的优先发展顺序和发展方向,为我国生物质能转换利用技术的发展和应用提供参考依据.  相似文献   

19.
近年来,随着大学办学规模的不断扩大,大学校园的面积也在不断扩大。然而,由于招生规模的不断扩大,校园内的运动场地愈发紧张。针对校园运动场地与学生运动需求的矛盾,文章以福建农林大学校园为例,以校园内的运动场地为感知客体,建立评价指标体系;综合运用AHP法、SD法、因子分析法对校园内运动场地的满意度进行综合评价和分析,以期为大学校园运动场地的优化和管理以及运动场地的新建提供建议。  相似文献   

20.
Indonesia has abundant forest biomass resource, which should not be considered as a low economic value resource. This forest biomass resource can be converted into bioenergy through various technologies and it becomes one of sources in Indonesia's energy mix. This paper focuses on forest residues generated primarily from the harvesting of natural production forests and industrial forest plantations; and wood processing mill residues. The estimated total potential forest biomass in Indonesia for bioenergy in the year 2013 was 132 PJ. About 50.4% resulted from harvesting residues and 49.6% from wood processing residues. Riau province has the largest potential bioenergy followed by Central Kalimantan, East Kalimantan, East Java, South Sumatera, Central Java and Jambi, which all together accounted for 87% of total potential bioenergy. Moreover, three major islands accounted for 95% of total potential bioenergy. Using a conversion return approach, the economic value of forest biomass when it was pelletized was estimated to be about US$ 5.6 per ton wood residues. The economic value of forest biomass is more sensitive to changes in the price of wood pellet than to changes in the collection and hauling cost of wood residues.  相似文献   

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