社区林业政策对尼泊尔农村生计的影响

尼泊尔引入社区林业管理已有20多年。虽然有社区林业管理促进了公有林和私有林树木生长的报道,但其对当地社区获得林产品,如木材、薪柴,以及其他非木材林产品(NWFP)的促进作用还没有完全得到证实。此外,社区林业的介入有明显的社会效益。通过资料收集和实地考察分析了尼泊尔中部山区执行社区林业政策对社会经济的影响。     

伐区机器人

伐区作业能否实现自动化?其它工业部门的经验表明,这是完全可能的。我们认为,在伐区可以使用多种用途的万能自动化系统,即机器人。根据 A·B·季莫菲耶夫在《机器人与人工智能》(莫斯科《科学》出版社1978,192页)一书的定义:“在主动与周围环境相互作用的过程中善于学习,并能用来模拟人在体力或智力劳动过程中完成各种作业的万能自动化系统”称为机器人。工业发达的国家,正处于推广程序机器人的生产和使用阶段。目前,这种机器人将近一万个。美国、日本、瑞典及其它国家制造了二百多种程序机器人。苏联也在积极进行机器人制造与使用工作,研制了三十余种机器人,部分已成批生产。     

Standard for Bamboo and its International Trend

1 INTRODUCTIONNational forestry ecological engineering, as afundamental affair for environmental protectioncontains combating desertification, soil and waterconservation. Two measures might be taken to preventsoil and water losses. One measure is to enlarge theforest area and to stop cutting or to decrease cuttingforest so as to make forest coverage keep rising at astable speed, forest resources should be examined byremote sensing technology. The other is to control thecirculation of wood…     

Monitoring Forest Fire with MODIS-NDVI Images in Beijing

INTRODUCTION The moisture content of fuel is a critical parameter in fire ignition because flammability is closely dependent on it (Dimitrakopoulos et al. 2001). Dead fuel lying on the forest floor (fallen branches, litter, foliage) is the most dangerous because it is drier than live fuel and more dependent on rapid atmospheric changes. The moisture content of live fuel plays a marginal role in fire ignition, but it is critical in fire propagation modeling because the amount of water is d…     

Interface Characteristics of Wood-hybrid Composites

In recent years, many researchers all over the worldhave used inorganic compounds to improve theproperties of wood, for inorganic compounds are cheapand can be obtained easily. Furthermore, they havegood functions and are environmental-friendly if theyare well controlled (Chen Zhilin, 2003). Wood-hybridcomposite is a kind of organic-inorganic hybridmaterial(OIH). OIH means that organicmacromolecule material and inorganic material becomea mixed in molecule level to get excellent capabilities…     

Discussion on Private Forestry Development in China

1 HISTORICAL PROCESS ANDPRESENT SITUATION ON PRIVATEFORESTRY IN CHINABefore 1978, all the private sectors were bannedto own forest tenure in China. At that time, forestwas managed by state-run forest farms, state-runforestry industry bureaus or collectives. When thereform and opening-up policy was initiated inChina, with the implementation of HouseholdResponsibility System (HRS) in rural areas, privatesectors began to participate in forestry. In March1981, the State…     

Assessing Threats and Setting Conservation Priorities for Plant Species between Forest and Meadow Ecotone in Sanjiangyuan Nature Reserve, China

INTRODUCTIONA large number of nature resources have fosteredhuman beings in the world. However, during the lastfew decades these nature resources and biodiversitywere subjected to various anthropogenic pressuressuch as plantation, deforestation, construction ofhydro-electric project, overgrazing and exploitation andother developmental activities (He Youjun, et al, 2004b;Li Ang, et al, 2002; Swamy, et al, 2000). In order toprotect environment and biodiversity, we have to facethe challenge…     

Study on Impacts of pH Value on Paulownia Wood Color

INTRODUCTIONPaulownia is one of important species with fastgrowth and high yield oriented to industry uses inChina, paulownia wood is widely used in furniture-making, decorating materials, musical instrumentsmanufacture (Jiang Jianping 1990), etc. Brown orblack stain often appears on the surface of paulowniawood during processing and using. Discolorationseriously affects paulownia utilization, and it cancause huge loss due to low grade and price causedby stain (Cheng Junqing 1983a, 1983b…     

Genetic and Environmental Variations in Leaf Oils of Six Eucalypt Species

Chemical analyses were conducted with leave oils of Eucalyptus smithii, E. bakeri, E. polybractea, E. dives, E. radiata and E. macarthurii vvhich were introduced to southwestern China from Australia. It was found that the leaf oils of E. smithii, E. bakeri and E. polybractea contained 81-90% of 1 ,8-cineole, and E. dives and E. radiata contained higher a-phelandrene and piperitone. There vvere significant inter- and intraspeciflc variations in leaf oil yield, it also varied with seasons in vvhich leaves vvere harvested. The results suggested that more research should be undertaken to identify genotypes with high-yield of leaf oils. These species could be applied to develop community forestry.