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简要介绍阿坝州在实施生态工程建设中造林绿化的情况,并根据阿坝州的立地条件,气候条件等因子分析了在干旱河谷和半干旱河谷地带,阳坡和半阳坡地带,阴坡和半阴坡地带运用地膜覆盖技术的造林试验和应用前景。 相似文献
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<正>石灰岩山区的阳坡和半阳坡土层薄、砾石多,干旱贫瘠,是造林绿化的难点和重点。经过近年来的摸索与实践,遵化市林业局的技术人员利用侧柏营养钵大苗在石灰岩山区阳坡和半阳坡进行人工雨季荒山造林取得了比较显著的效果,在该地区的荒山披绿工程中发挥了积极作用。1整地整地是造林过程中的一个基础环节。由于石灰岩山区干旱缺水、土薄地贫,立地条件差,因此高标准整地对苗木成活就显得尤为重要。在土壤分布不均、坡面破碎的山地造林,大鱼鳞坑整地 相似文献
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针对冀北山地造林树种短缺的问题,选择黄檗(Phellodendron amurense)、华山松(Pinus armandii)、毛棶(Cornus walteri)、花楸(Sorbus pohuashanensis)、胡桃楸(Juglans mandshurica)、黄栌(Cotinus coggygria)6个树种进行造林试验,结果表明黄檗、胡桃楸、毛梾、华山松和花楸5个树种均适宜在阴坡宜林荒山造林,黄栌适宜在阳坡宜林荒山造林,可作为本区宜林荒山人工造林树种。黄檗在半阳坡宜林地造林虽然成活率与保存率较高,但生长量与健壮程度显著低于阴坡造林地,因此水肥条件差的半阳坡宜林地不宜营造黄檗林。胡桃楸在石质沟谷地造林虽然生长量与保存率低于阴坡造林地,但保存率在85%以上且生长较好,为该立地条件较佳的造林树种和造林模式。 相似文献
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阳坡、半阳坡干旱,土层浅,立地条件恶劣,造林投资大、成活率低,一度被视为禁区。总结了东会林场阳坡、半阳坡油松、华北落叶松造林成功的经验,介绍了阳坡、半阳坡造林技术。 相似文献
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论辽宁省造林绿化目前存在的问题和解决对策王伯铎（辽宁省林业厅造林处沈阳１１０００１）辽宁省是森林资源较少的省份，全省有林面积４１５万ｈｍ２，森林覆盖率为２８．７％．按现在有林面积计算，已绿化面积占全省规划到本世纪末实现绿化规划造林任务的８０％。造林绿... 相似文献
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酸石榴干旱阳坡造林技术研究 总被引：1，自引：0，他引：1
针对大行山干旱阳破造林树种单一，成活率低，经济效益低等问题，采用不同坡向、整地方法、造林时期、截干高度，进行酸石榴造林技术研究。结果表明：选择阳坡，断沟状整地，８月上旬（雨季）截干（保留干高２０～４０ｃｍ）栽植，成活率可达９５％以上。 相似文献
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随着世界银行贷款三期造林、太行山绿化工程、京津风沙源治理工程等重点林业工程的全面实施，五台林区立地条件较好的宜林地基本上披上了绿装，剩下了立地条件较差的宜林地，其中干旱阳坡造林比例逐渐增大。如何保证造林成活率，已成为五台林区营林工作的关键。为了解决干旱阳坡造林技术难题，我们将各林场干旱阳坡造林的小经验、小措施融合在一起，并结合一些适合当地的新办法、新技术， 相似文献
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四川国有林区伐区更新造林检验管理信息系统的研建开发＊方建刘清龙（四川省甘孜州林业检验处）李国明（四川省林业厅）前言四川是全国重点林区之一。全省国有林业生产单位每年承担着完成４００多万立方米商品木材和约１．５万公顷迹地更新，以及近０．６万公顷成片造林的... 相似文献
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提高人工直播造林成效技术措施探讨①郭利华赵义民毛海生（河南省林业勘察设计院）为了加快绿化速度，巩固和提高飞播造林成效，１９９１年以来我省积极开展了人工直播造林。截至１９９４年底累计直播造林９７３３３ｈｍ２，其中合格面积７１３３３ｈｍ２，占直播造林面积... 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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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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以德国南部小城镇加米施-帕滕基兴(Garmisch-Partenkirchen)市为例,在介绍该市园林绿化概况的基础上,重点介绍其民居庭院绿化与阳台绿化的特色;并对如何更好地发展中国小城镇绿化进行了探讨。
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森林病虫害防治是国家减灾工程的重要组成部分,对保护森林资源,改善生态环境,促进国民经济和社会可持续发展具有十分重要的意义。 相似文献