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森林认证对林产品贸易的影响 总被引：6，自引：0，他引：6
森林认证在森林经营政策方面扮演了一个重要的补充角色并对林产品贸易起到了极其重要的影响。在短短的10余年间,森林认证已得到许多国家政府和林业部门的关注和认可。森林认证工作在中国刚刚起步,我们应该让更多的人了解森林认证并推动该项工作的发展。本文分析了森林认证对世界林产品贸易的影响,包括认证进出口国的利益、贸易流向、企业竞争、以及人们对认证林产品的需求,论述了森林认证对中国林产品贸易的影响,提出了森林认证对中国森林经营和林产品贸易的影响是机遇与挑战并存。参8。 相似文献
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Pan Jianping 《林业研究》1995,6(1):23-26
The disastrous fire occurred in northern area of Daxing’anling forest region on May 6, 1987, destroyed a large area of forests.
The broad-leaved tree species, such as poplar, birch had regenerated in a great quantity after the fire, but the coniferous
species such as larch and scotch pine had difficult to regenerate naturally, This paper put forward that the coniferous forest
could be recovered by the planting method of effect strip and effect islet based on the principle of borderline effects and
by making full use of the condition of broad-leaved trees. 相似文献
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长白山典型林区森林资源变化及目前质量分析 总被引：4，自引：0，他引：4
利用研究区1985年和1999年两期遥感数据,将两期图像的矢量化图像中变动幅度较大的主要类别进行叠加,通过图像单元统计及图像叠加分析,得知各类地物在十五年间的变化情况及相应类别变化的量化归属。研究表明,十五年间采伐迹地、人工幼林变化剧烈,人类活动是造成研究区地物剧烈变化的最主要原因。选择研究区中二个干扰与经营状况不同的林场进行重点剖析,结果表明经营强度及方式的不同,对森林资源质量有较大的影响。东升林场采伐利用强度相对较小,目前仍保存有面积约占该林场1/3左右的地带性植被,过熟林面积比例较高,成熟针叶林单位面积蓄积量高达536.27m3hm-2,与长白山自然保护区的阔叶红松林单位面积蓄积量大体相当;西林河林场因采伐强度较大,目前林分多为原始林被破坏后形成的次生林,成过熟林比例相对较低,单位面积蓄积量也较小。二个林场森林状况以及营林措施方面具有一定代表性,其森林演替具有天然、人为干预两个方面的性质,作为重点剖析对象对研究区未来森林资源经营具有一定的指导意义。本文还就研究中发现的问题进行了剖析,并对当地的营林策略提出了可行性建议。图6表4参13。 相似文献
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YUDe-yong HAOZhan-qing XlONGZai-ping WANGDian-zhong YANGXiu-ying 《林业研究》2004,15(3):171-176
The utilization and changes of forest resources were studied in the Lishuihe Forest Bureau. Based on remote sensing images in 1985 and 1999, changes of major forest resources were analyzed by statistical and overlap method and classified quantitatively. The results showed that in recent 15 years, logging spots and man-made young forest changed violently, which was due to human activities. Different forest management manners and harvesting intensity played an important role in forest resources change. Dongsheng and Xilinhe tree farms were typical cases of different forest status and management for the Bureau, where forest succession was intervened by either human or natural disturbance. Dongsheng Tree Farm underwent a lighth arvest intensity and maintained a unit stock volume of 536.27 m^3. hm^-2, as much as that of broadleaf/Korean pine forest of Changbai Mountain Natural Reserve; Xilinhe Tree Farm underwent an intense harvest and was composed of secondary forests,where mature forests just had a small percentage and the unit stock volume was low. The study was useful to guide future forest management. What‘s more, problems found in the research were also analyzed and reasonable advice was given to the local forest management. 相似文献
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The current forest planning system of Japan has been in place since the formulation of the Forest Law back in 1897. During this time, although addressing specified forests as demonstrated in the system for protection forests, in a more general sense, the execution of the forest planning system has placed forestry management at the core. In other words, it has instead been forest administration delivered in a manner relevant to forestry management. This trend is exhibited in, for instance, policies for the reorganization of common forest, the forest management planning system, forest owners associations, the proceeds-sharing reforestation system, cooperative silviculture management, and valley forestry revitalization; which have all been implemented.In this paper I review the results of these practices and explore the contemporary forest owners pattern of behavior. I also discuss the passive attitudes among forest owners, especially in comparison with the attitudes prevalent during the postwar reforestation era, continuing up to the 1960s, and the current tendency towards neglect in the afforested areas, as well as the increasing number of forest owners giving up forestry practice.In the postwar era (up to the 1960s), forestry had been following an upward trend of development that motivated forest owners to afforest, as this was the optimal choice for increasing the familys stocks for future generations (in the manner of holding an asset), and thus a rapid expansion of plantation forests resulted. By the 1970s, when domestic wood supply became less than a half of all domestic wood demand (it is still declining now), forest owners gradually began to lose interest in reforestation and care of the forest as a method of increasing assets. The current share of domestic wood supply in total consumption has dropped to 20%, and the annual cut volume is only 23% of the annual volume increment.Forests are as much a public property as they are private and, moreover, represent a globally significant resource. Active stewardship, such as materializing internationally agreed notions of sustainable forest management, promoting forest certification systems, and complying with the Kyoto Protocol, are now important issues, both domestically and internationally.The paradoxical gap between current forestry trends and public aspirations for forests is widening with each year, thus creating a grave social problem. I have been focusing on forestry revitalization as the primary step towards the resolution of this issue. As the logical basis for executing this policy, I review the relations between forest resource policies and forestry policies.At the same time, by reviewing the forest planning system and its developmental process, I sought to investigate what new policies would fulfill the need to realize the public functions of forests while revitalizing forestry, form the point of view of forestry policies and their influence on the forest planning system. I have concluded that there is a case for separating forest management from forest ownership in units of forest compartments; namely to establish an incorporative management system by which forest owners can invest in their stands. 相似文献
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分析了完达山区域水平地带性和垂直地带性的森林特征,并对该林区不同区域分布的不同森林类型进行了评价。 相似文献
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结合沾益县实际情况和各类经济建设规划,指出沾益县制定林地使用控制规划的必要性,并着重从林地资源消长分析、使用林地数量控制、使用林地总量控制三方面简要介绍了沾益县林地使用控制规划的主要内容。 相似文献
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The forest resource of Heilongjiang province has important position in china. On the basis of the six times of national forest inventory data （1973-1976, 1977-1981, 1985-1988, 1989-1993, 1994-1998, 1999-2003） surveyed by the Forestry Ministry of P. R. China from 1973 to 2003, the carbon storage of forests in Heilongjiang Province are estimated by using the method of linear relationship of each tree species between biomass and volume. The results show that the carbon storage of Heilongjiang forests in the six periods （1973-1976, 1977-1981, 1985-1988, 1989-1993, 1994-1998, 1999-2003） are 7.164×10^8 t, 4.871×10^8 t, 5.094×10^8 t, 5.292×10^8 t, 5.594×10^8 t and 5.410×10^8 t, respectively., which showed a trend of decreasing in early time and then increasing. It indicated that Heilongjiang forests play an important role as a sink of atmospheric carbon dioxide during past 30 years. Based on the data of forest fires from 1980 to 1999 and ground biomass estimation for some forest types in Heilongjiang Province, it is estimated that the amount of mean annual consumed biomass of forests is 391758.65t-522344.95t, accounting for 6.4%-8.4% of total national consummation from forest fires, and the amount of carbon emission is 176 291.39t-235 055.23t, about 8% of total national emission from forest fires. The emission of CO2, CO, CH4 and NMHC from forest fires in Heilongjiang Province are estimated at 581761.6-775682.25 t, 34892.275-46523.04 t, 14091.11-18788.15 t and 6500-9000 t, respectively, every year. 相似文献
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lNTR0DUCTI0NTheauthorhadachancetotakepartintheinvestigationworkofTibetforest.WestartcdfromLhasa(elevation3658m)'wentdownalongNiyangandYaluzangburivers,crossedtheMinlaMountainGorgeelevated4900mandSeJilaMountainGorgecIevated472()m,wentthroughMozhugongka'Gongbu-JiangdaandothercountiesandgotintothemainforestareaofTibet.Linzhi(elevation3()()0m).thenwenttlu-oughTongmai(ele\'ation2l00m)torcachBomi(elevati0n275()m)whichwasthebigforingplaceofYaluzangbukiver.Theinvestigationonforestplantdisea… 相似文献
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文章通过乌兰夫纪念林的建设,就红色革命老区如何推进城市森林建设,城市绿化如何与红色文化结合、如何赋予绿色载体的爱国主义革命传统教育,如何展示林业工程的政治内涵和文化内涵进行深入思考并提出切实可行建议。 相似文献
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A multi-criterion index for the evaluation of local tropical forest conditions in Mexico 总被引：1，自引：0，他引：1
S. Ochoa-Gaona C. Kampichler B.H.J. de Jong S. Hernández V. Geissen E. Huerta 《Forest Ecology and Management》2010
Despite the ecological and economical importance of tropical forests they are currently affected by human activities, mainly through deforestation and selective extraction. With the aim of making an opportune diagnosis of the condition of forests, we developed an ecological index based on qualitative and semi-quantitative data, allowing a quick diagnosis in order to manage and conserve tropical forests. We evaluated 44 plots of tree vegetation, measuring canopy height, number of strata, tree cover, dominant trees, number of tree species, as well as the management of and damage to the forest. The data of each parameter was classified in categories of 3, 4 or 5, which were normalized between 0 and 1 for the worst and best characteristics, respectively. For the purpose of analysis, the average, a set of IF–THEN rules, and fuzzy logic were applied and as a result we obtained a model that measures the ecological condition of the tropical forests. The model has the advantages of having an ecological basis, allows data to be gathered quickly and is clear and easy to manage and interpret. When running the model, the value of each intermediate variable is displayed, thus allowing the detection of where necessary action is required to improve the ecological condition of the forest. We expect this index to contribute in evaluating the effectiveness of forest management and possibly offer advice for the short-term management and conservation of the remnants of tropical forests. 相似文献
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保证森林采伐与天保工程有机的统一.首先要提高采伐与天保工程统一性的认识;然后要合理采伐.大力培育速生护林;其次要处理好当前与长远的关系。 相似文献
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In the western Mediterranean region of Catalonia (NE Spain), during the last 20 years of the 20th century, the range of many forest bird species has expanded. Our objective was to characterize the roles of (a) spatial population processes (related to dispersal), (b) changes in forest structure (due to forest maturation and management), and (c) landscape composition (resulting from afforestation and fires) in the range expansion of these bird species at the landscape scale (10 × 10 km). After correcting for the differences in sampling effort, colonizations appeared to be more likely near areas in which the species had been present in the 1980s. Patterns of the range expansion were also strongly associated with forest maturation, which seems to affect the spatial arrangement of birds at multiple scales. Changes in forest landscape composition due to afforestation and fires were minor determinants of range changes, and forest management did not seem to prevent range expansion at the spatial scale studied. Colonization events appeared to be driven primarily by landscape changes occurring in nearby localities rather than within the colonized locations themselves, presumably because of source–sink dynamics and connectivity patterns. Our results showed that in Catalonia, at a landscape scale, the impact of forest management on forest bird communities is much smaller than the impact of the widespread maturation of forests following a large-scale decline in traditional uses. 相似文献
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