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Eucalypt plantations 总被引：7，自引：0，他引：7
This paper reviews the historical development of the use of the eucalypt over 200 years, from its curiosity status in the botanical gardens of Europe to its extensive use as a fuelwood for the wood-burning locomotives of the national railway systems, and then to its more recent use as a major source of biomass for paper pulp, fiberboard, industrial charcoal, and fuelwood. Ecological and biological aspects of the genus Eucalyptus have made it successful as an exotic in industrial monocultures and as a multipurpose tree of benefit to small landholders. Social, policy, and economic aspects of growing Eucalyptus are examined, as are prospects for using the eucalypt in the twenty-first century as an industrial plantation tree and as a component of farming systems in the rural landscape. 相似文献
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本文从天然林的主要特点、功能和作用出发,论述了保护天然林资源的重要性,以及从砍伐天然林为主到砍伐人工林为主的这一转变的历和现实的必然性。 相似文献
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Natthanon Phaiboonsilpa Kazuchika Yamauchi Xin Lu Shiro Saka 《Journal of Wood Science》2010,56(4):331-338
Two-step hydrolysis of Japanese cedar (Cryptomeria japonica) was studied as treated by semi-flow hot-compressed water at 230°C/10 MPa for 15 min and 280°C/10 MPa for 30 min as the first
and second stages, respectively. At the first stage, hemicelluloses and para-crystalline cellulose, whose crystalline structure
is somewhat disordered, were found to be selectively hydrolyzed, as well as lignin decomposition, whereas crystalline cellulose
occurred at the second stage. In all, 87.76% of Japanese cedar could be liquefied by hot-compressed water and was primarily
recovered as various hydrolyzed products, dehydrated, fragmented, and isomerized compounds as well as organic acids in the
water-soluble portion. The remainder, 12.24%, could not be hydrolyzed and remained as the water-insoluble residue composed
entirely of lignin. Based on the distribution of various products from hemicelluloses in Japanese cedar, their decomposition
pathways were proposed as independent. 相似文献
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牟定县油茶产业发展现状与对策分析 总被引：2，自引：0，他引：2
介绍云南省牟定县适宜发展油茶产业的气候、土壤、土地资源、种苗供应等自然条件,发展木本油料产业的经验、投资环境优越等社会条件,以及油茶在牟定县的发展历史及现状.分析了油茶产业发展中存在的技术含量低,扶持力度不够,政策保障措施不够细化等问题,藉此提出了科学经营、实行行业标准化栽培管理、扶持龙头企业、建立油茶专业合作组织等对策. 相似文献
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广东省红树林生态系研究展望 总被引：2，自引：0，他引：2
广东省是我国红树林分布面积最大和台风多的省区,也是国际候鸟迁徙路线上停歇和越冬的主要站点,在减灾防灾、生物多样性和污染物生态修复等方面有极其重要的研究意义。因此,广东省红树林生态系研究要着重解决广东省现有红树林的生物多样性调查、生态功能评估、生态系统经营、大量红树果实加工利用、沿海困难滩涂与堤岸红树林营造等技术问题,为其红树林生态系恢复与管理及其红树林生态系资源的可持续利用提供技术支撑。 相似文献
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A Miscanthus Sinensis plantation in Galicia, Spain, provided the raw material for experimental fiberboards. After harvesting, the Miscanthus stems were cleaned and chipped. The chips were steam exploded with a thermo-mechanical aqueous vapor process in a batch reactor. The resulting material was dried, slightly milled, and used to produce fiberboard with no synthetic binders. The pretreatment and the pressing conditions that optimize the physico-mechanical responses were determined. Response surface methodology with a central composite design was used. The variables studied and their respective variation ranges were: pretreatment time, 4–14 min; pressing temperature, 195–245°C; pressing pressure, 1.9–14.6 MPa. The boards obtained were very good quality (modulus of elasticity as high as 7630 MPa, modulus of rupture as high as 61 MPa, internal bond as high as 4.1 MPa, thickness swelling as low as 2.5%, and water absorption as low as 8.9%) and more than satisfied the requirements of the relevant standard specifications. 相似文献
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介绍紫皮石斛种苗培育的有性及无性繁殖方法,阐述其栽培时间、地块的选择、整地方式、设施条件、基质制作与铺设、以及自然树放养法、木槽放养法、床式栽培等栽培方法.对田间管理的光照、温度、水分、霜冻、施肥等管理环节以及主要病虫害的防治技术等也作了阐述. 相似文献
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桉树人工林昆虫群落结构及其多样性初步调查 总被引：2，自引：0，他引：2
对桉树人工林系统昆虫种类进行调查和鉴定,记录了桉树人工林昆虫种类共有16目63科106种．从群落物种数来看．鞘翅目的物种丰富度最高（20．56％）;从物种的个体数量看,鳞翅目昆虫的数量最多（30．71％）;桉树林昆虫总的群落多样性指数为1．3933,均匀性指数为0．9301,鞘翅目的群落多样性指数（0．2937）和均匀性指数（0．2108）都最大．文中就昆虫群落多样性与稳定性的关系以及如何抑制害虫发生等问题进行了讨论． 相似文献
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Past,current and future drivers for the development of decision support systems in forest management
The potential for development in decision support for forest management is set by decision theory, available technology and methods. Demands for decision support are emerging from contemporary challenges and problems of forest management which act as stimuli for the science community. Objectives and approaches in forest management as well as technologies have been changing throughout history. Accordingly, the demand for tools to support planning and decision-making has evolved. In this contribution, the authors review the historic development of decision support systems (DSS) for forest management and discuss past, current and future drivers. Based on evidence from scientific literature, case studies in the frame of the Forest Management Decision Support Systems (FORSYS) action, as well as experiences of the authors some hypotheses about the future of DSS are drawn. It is shown that in the past, the drivers evolving from forest management as well as decision support technologies have influenced the way of how models and methods have been applied as well as how DSS architectures have been designed. It is concluded that in the future, the challenges for DSS development will increase, as the complexity of decision-making processes and the related models will compete with the user demands which ask for simplicity. 相似文献
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在分析森林旅游产品基本内涵的基础上,充分考虑森林旅游产品的特征、发展趋势等因素,总结出森林旅游产品的开发模式,即以可持续发展为原则、以主题定位为理念、以产品创新为核心、以休闲体验为重点、以乡土开发为特色。以期对不断发展的森林旅游产品开发及经营提供建议和参考。 相似文献