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《中国林业科技(英文版)》2010,(1):67-73
In China, Pinus pumila is mainly distributed in Daxing’anling, while those growing in the eastern Daxing’anling are primarily covered under the jurisdiction of Huzhong Forest Bureau. P. pumila is an evergreen shrub, 3-6 m high, and always grows vigorously. Its trunks creep along the ground, usually 10 m long or more. It is easily flammable because of the large amounts of resins and volatile oils in its body. Attacking forest fires is a dangerous work, especially in P. pumila scrubs. The fires in P. pumila scrubs are very different from those in other forest types, e.g. fierce combustion and heavy smoke. In this paper, the distribution characteristics of P. pumila scrubs were presented. Attacking techniques and safety precautions for attacking fires in P. pumila scrubs were also discussed. 相似文献
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《中国林业科技(英文版)》2010,(4):59-64
In recent years, many serious forest fires occurred in precious Pinus pumila forests in Daxing'anling Mountains of Heilongjiang Province and Inner Mongolia. But up to now, there is still a lack of proper understanding of fire occurrence environments in P. pumila forests. In present paper, we investigated and studied the fire occurrence environments. The results showed that fires in P. pumila forests had their own special fire environments. Abundant fuel, drought weather, dry thunder and high altitude terrai... 相似文献
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通过户外观测和室内饲养,在吉林市对危害榆树Ulmus pumila及其变种垂榆Ulmus pumila var.pendula,金叶榆Ulmus pumila‘Jinye’的害虫进行多年调查研究。明确害虫种类的同时,发现5种新害虫。其中,库鞘蛾Coleophora kuehnella(Goeze)和榆花象Anthonomus yuasai K?no为中国新记录种;黄腹异跗萤叶甲Apophylia eoa Ogloblin、双条隐头叶甲Cryptocephalus sinensis Weise和黑盾肿鳃长蝽Arocatus rufipes St■为吉林省新记录种。记述这5种害虫的形态特征、发生时期和危害特性等,并配有生态照片。 相似文献
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垂榆是白榆(Ulmus pumila)的变种(Ulmus pumila var.pendulaRehd.),从新疆引种到内蒙古。由于垂榆在集通铁路沿线未有嫁接栽植,从1999年至2003年,在商都铁路苗圃进行了较系统的嫁接试验,并用该苗木在集通铁路沿线的锡林郭勒盟白旗和桑根达来地区进行了栽植试验,取得了具有实用价值的试验数据,为该地区栽植垂榆提供了宝贵的经验。 相似文献
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LIU Gui-feng DONG Jing-xiang JIANG Ying LU Yan-fang JIANG Jing ZHAO Guang-yi 《林业研究》2005,16(3):213-215
Genetic relationship of 12 species of Section Strobus was analyzed with ISSR markers. 117 loci were detected with 12 ISSR primers. Percentage of polymorphic bands （PPB） varied from 5.93% to 19.92%. P. pumila had the highest levels of genetic differentiation and P. flexilis had lowest. Total genetic diversity （Hr） of 12 species in Section Strobus was 26.21%, of which intraspecific genetic diversity （Hs） was 7.66%, and interspecific genetic diversity （DST） was 18.55%, and the genetic variation in interspecies accounted for 70.78% of the total genetic diversity. According to the cluster results of genetic distance, the 12 species were classified into two groups. The first group included P. griffithii, P.armandi, P. fenzeliana, P. kwangtungensis, P. strobus, P. monticola and P. wangii. The second group included P. albicaulis, P pumila, P. flexilis, P. sibirica and P koraiensis. 相似文献
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WANG Mingyu SHU Lifu TIAN Xiaorui LI JieInstitute of Forest Protection Chinese Academy ofForestrv Forest fire management office. State Forestry Administration 《中国林业科技(英文版)》2003,(4)
Lightning fire is one of natural fires; its mechanism is very complex and difficult to control. Daxing'an Mountain is the main region that lightning fires occur in China. Research on lightning fires indicates that special fuel, dry-storm weather and high altitude form the lightning fire environment. Lightning fires have close relation with lights. When lightning occurs, especially dry-lightning which brings little precipitation with surface temperature growing and fuel dehydrating, these often lead to lightning fires. Lightning fires have characteristics of geography, time and topography. The higher altitude forest region in Daxing'an Mountain, the more lightning fires occur. Valley with altitude above 800 m in the north of 51.N and Larix gmelinii-Pinus pumila, Pinus sylvestris var. mongolica -Pinus pumila forests on the top of mountain are the most concentrating region where lightning fires occur. One serial dry-storming can ignites many lightning fires, the furthest between them is as long as 150 km. 相似文献
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中华金叶榆（Ulmus pumila cv.jinye）,榆科榆属,系白榆变种。叶片金黄色,有自然光泽,色泽艳丽;叶脉清晰,质感好;叶卵圆形,平均长3~5cm,宽2~3cm,比普通白榆叶片稍短;叶缘具锯齿,叶尖渐尖,互生于枝条上。中华金叶榆是由河北省林业科学研究院、 相似文献
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<正> 榆长喙壳菌[Ceratocystis ulmi (Buism.)C. Morean]属子囊菌纲,小囊菌目。无性阶段为Graphium ulmi Schwartz;同种异名为Ophiostoma ulmi (Buism.) Nanrf、Ceratosto-mella ulmi Buism;普通称为荷兰榆病。寄主主要寄主是榆树(Ulmus spp.)。美洲榆(U. americana)很易感病;而亚洲的榆树,如西伯利亚榆(U. pumila)则较抗病。 相似文献
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(10)桴树Glandbearing Oak 或Japanese Quercus glandulifera Bl.Silkworm Oak(11)大果栎Bur Oak,Mossy—cup White Quercus macrocarpa Michx.Oak 或Overcup Oak (栽)(12)沼栎Pin Oak 或Swamp Spanish Quercus palustris Muenchh.Oak, (栽)10.榆科Elm Family, Ulmaceae(1)刺榆David Hemiptelea, Hemiptelea davidii Planch(2)榆Dwarf Elm,或Siberian Ulmus pumila L. 相似文献
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本文建立了苹果(Malus pumila Miller)果实品质鉴评的模糊综合评判模型,并对苹果品种元帅(Delicious)的果实品质进行模糊综合评判。 相似文献