共查询到20条相似文献,搜索用时 78 毫秒
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辽宁省沙棘资源现状及发展对策 总被引:1,自引:0,他引:1
辽宁省沙棘引种驯化及开发利用研究起步于20世纪50—60年代。据统计,全省现有人工沙棘林面积达13.33万hm^2,沙棘加工企业10余家,年产值达6000多万元。沙棘不仅有效地提高了辽宁省干旱、半干旱地区的植被覆盖率,改善了生态环境。同时,沙棘已逐渐发展为一项开发潜力较大的生态型产业。章针对目前辽宁省沙棘资源保护和产业发展中存在的问题,提出了一些合理的对策和建议:突出沙棘在生态建设中的地位和作用,加大沙棘建设力度;加强沙棘资源的管理,保证资源的可持续利用;大力发展沙棘产品精深加工业,推进沙棘产业化进程;加强沙棘科学研究,提高沙棘资源经营管理水平;切实加强领导,为沙棘建设与开发创造良好的环境。 相似文献
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关于搞好沙棘资源行业管理的思考张广军(西北林学院)1我国的沙棘资源及开发利用现状从80年代中期起,我国的沙棘开发利用形成了热潮。经林业、水利、轻工、医药等部门的相互配合,有关专业人员及产区人民群众的共同努力,我国的沙棘资源建设及开发利用均呈现出蓬勃发... 相似文献
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太原市郊不同产区沙棘果实成分分析 总被引:1,自引:0,他引:1
山西省的沙棘资源占全国的50%,开发利用沙棘资源有着良好的前景。现对太原市郊不同自然类型区的沙棘果实成分进行了分析测试,以为沙棘品种选育和营造人工沙棘林及综合开发利用提供参考数据。 相似文献
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镇赉县是国家林业主管部门确定的全国30个沙棘产业建设重点县之一。搞好沙棘产业化建设对于促进镇赉县乃至全省农业经济发展,农民脱贫致富奔小康以及防风固沙、保护农田、改善农业生产条件具有重要意义。目前,镇赉县沙棘资源建设仍处于发展阶段。为了今后的沙棘产业化建设和管理,要扩大面积,形成规模;引进良种,营造沙棘园;建立沙棘系列产品加工厂,做好对沙棘资源的开发利用;加强组织领导,建立管理技术保障体系,使沙棘种植和加工形成良性循环。 相似文献
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南斯拉夫共有杨柳树林地15万公顷,仅占森林面积的1.5%,但其木材产量却占全国木材总产量的8%。杨木产量由1950年的10立方米,提高到1985年的120万立方米,增加了11倍,成为当今国际杨树委员会的重要成员国之一。该国杨树发展速度之所以快,与其有一支稳定的科研队伍密切相关。本文较详细地介绍了南斯拉夫杨树育种的成就和经验,并结合我国的实际情况,提出了作者的看法和建议。 相似文献
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美洲黑杨及其杂种在世界和我国杨树栽培中的地位与作用 总被引:2,自引:0,他引:2
本文介绍了美洲黑杨的天然分布, 生长状况。西欧各国对其珍贵基因资源的重视和利用, 我国引种美洲黑杨的现状及其作用等, 并对我国进一步利用美洲黑杨的基因资源, 促进我国杨树栽培的发展提出了一些看法。 相似文献
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由于特殊的地理和气候特征。使甘孜州高丘区阳坡,半阳坡以及金沙江,雅砻江,大渡河等“两江-河”河谷及其干流的绿化成为全州,全省,全国乃至全世界造林难题之一。目前甘孜州造林已经由立地条件较好的深沟采伐迹地更新全面转向上述难造林地区。通过多年的摸索。认为甘孜州造林要依靠科技,充分挖掘,利用州内丰富多样的植物资源,从解决四大问题入手,一是绿化思路(先灌,草绿化覆盖,后乔,灌结合造林;突破常规的投入和设计,实行稀树造林,宽带造林和多种围栏造林)的突破与创新,二是造林树草种(乡土地草种的选择和全光照营养袋培育雨季造林)选育,三是造林后期管护(落实专人,村组农户,专业队),四是进一步密切造林本身与广大农牧民增收的关系(发展名特优干果,地道药材的人工,半人工抚育和种植,造林绿化与环境美化,香化,服务生态旅游事业),逐步解决林牧矛盾,林农问题,不断提升林业在社会,经济发展中的地位和作用。 相似文献
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实施西部大开发,再造祖国秀美山川,是以江泽民同志为核心的党的第三代领导集体高举邓小平理论伟大旗帜,把握历史,面向未来,高瞻远瞩,审时度势,总揽全局,站在跨世纪我国经济发展的战略高度作出的决策,是加快西部地区经济发展,逐步缩小东西部地区差距,确保国家长治久安,人民安居乐业,促进共同繁荣,实现中华民族伟大复兴的重要举措。在实施西部大开发中,人力资源的开发与利用至关重要。 相似文献
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D. G. Hunt 《Wood Science and Technology》1989,23(4):323-333
Summary Non-linearity of softwood in axial mechano-sorptive creep during moisture cycling can be characterised as departure from linear behaviour. Linear behaviour is shown by experimental measurement to be a gradual approach to a creep limit with exponentially decreasing increments of compliance, Ji, per moisture cycle, when tested under a constant stress. On the other hand, when the stress is progressively increased by a small increment after each moisture cycle, the compliance increments will progressively increase, having a value of
, where n is the cycle number. By subtracting one compliance increment from the succeeding one, the value of Ji can be obtained. Analysis of experimental results in bending tension and compression showed that the compression test pieces departed from linearity at total strains around 0.14% to 0.15%, the bending test pieces showed slight evidence of non-linearity at about the same strain, whilst the tensile pieces were approximately linear up to 0.18% strain.This project was supported by the U.K. Science and Engineering Research Council and by the European Commission 相似文献
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文章简要地分析了围垦湖沼、上游截流、过度利用及工艺技术落后等人为因素对湿地资源的破坏情况与负面影响,给人们赖以生存的湿地生态环境带来严重的不可逆转的后果,并有针对性地提出了几点建议。 相似文献
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Forest cover change is one of the defining contemporary environmental changes that validate the proposition of the Anthropocene narrative. Forest transition is a well-recognized global phenomenon, which has been studied and explained in well elaborated forest transition theory. Forest transition has been observed in over 30 countries, and it has been a trend in multiple countries in Asia. Forest transition is most relevant for the Anthropocene narrative, as it suggests that forest cover decline may eventually be followed by a forest cover increase at the global scale. The paper reviews evidence of forest transition in eight Asian countries and juxtaposes this with global forest cover trends. In Asia countries like China, India, Japan, Philippines, South Korea, and Japan and Vietnam are among the countries that have experienced an increase in the area under some kind of tree cover. Complex interplays of forest cover, population growth, economic development, demand for forest goods and services and governance effectiveness are the driving forces of forest transition. While it is not possible to extrapolate Asia's forest transition to the global scale, the Asian experience makes it possible to make statements on possible global forest cover scenarios. Ultimately, forest transition theory in general, and the experience of forest transition in Asia also support the concept and related narrative of the Anthropocene. 相似文献
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Mir Mozaffar FALLAHCHAI 《中国林学(英文版)》2012,14(2):131-136
In this study the regeneration diversity of Syahkal forests afforestated and natural stands in north of Iran was studied and compared from the point of view of evenness and diversity index.In order to accomplish this study two natural and man-made stands that almost are located in the same height above the sea level were chosen.The area of each stand was 30 ha and the inventory was done by the random-systematic method with a 5R land measurement(500 m2)selected.Also,in order to study the regeneration in the center of each sample piece 125 square meters micro plots were formed.The results show that regeneration diversity index in natural stands is more than that in man-made stands which in this case Mc-Arthur index with 2.41 has the most amount while Simpson index with 0.543 has the least amount.But the evenness indexes in man-made stands are more than that in natural stand which the main reason is the purity of the man-made stand. 相似文献
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