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1.
为了查明阿尔泰山两河源国家级自然保护区树附生地衣物种组成成分,以及探讨影响该地区树附生地衣群落分布格局与环境因素之间的关系,以附生地衣覆盖度为指标,应用除趋势对应分析(DCA)对样点进行分组,运用典范对应分析(CCA)分析附生地衣分布与环境因素的关系,结果表明:1)阿尔泰山两河源自然保护区树附生地衣共有49种隶属于15科30属。2)根据DCA分析将该地区树附生地衣划分为3个样点组,样点组1共有地衣22种,总盖度为2.639%,物种多样性指数为1.603;样点组2共有地衣27种,地衣总盖度为3.717%,物种多样性最大为1.972;样点组3:共有地衣12种,地衣总覆盖度为1.036%,物种多样性最小量为0.871。3)CCA排序结果表明:低海拔区,人为干扰强度高,地衣多样性较低;中海拔区,森林郁闭度高,湿度适中,干扰较少,地衣多样性较高;高海拔区,森林郁闭度较低,树种较少,光强度较强,干扰较少,主要以壳状地衣为主,多样性较低。  相似文献   
2.
新疆北部山脉生态环境多样,是地衣植物生长分布的理想区域.根据多年的实地调查资料和前人研究资料,对新疆北部树花属(Ramalina Ach.)地衣的种类以及它们的分布区、区系成分和垂直分布进行了初步的研究.结果表明,分布在新疆北部的树花属地衣共有8种,它们分别是撕裂树花Ramalina dilacerata(Hoffm.)Hoffm.、粉树花Ramalina farinacea(L.)Ach.、岩生树花Ramalina intermedia (Del.ex Nyl.)Nyl.、裂树花Ramalina minuscule Nyl.、钝树花Ramalina obtusata(Arn.)Bitt.、粉粒树花Ramalina pollinaria(Westr.)Ach.、中国树花Ramalina sinensis Jatta、亚细长树花Ramalina subleptocarpha Rundel & Bowler等主要分布在天山和阿尔泰山.同时根据它们对环境的适应特征和选择性, 将新疆北部树花属地衣的地理分布区类型划分为如下2种:(1) 环北方种R.pollinaria,R.intermedia、 (2) 两极-大西洋种R.obtusata.研究还发现分布在阿尔泰山和天山的树花属的垂直分布有明显的差异.  相似文献   
3.
提取地衣真菌总DNA的简便方法   总被引:7,自引:0,他引:7  
利用液氮破碎地衣体的上下表皮层及藻层,再用氯化苄在弱碱条件下破坏真菌细胞壁,从而获得地衣真菌总DNA.此方法简便、省时、价廉,获得的总DNA蛋白质污染少,产量高,可进一步进行PCR扩增.  相似文献   
4.
叶嘉  张浩  韩留福 《安徽农业科学》2010,38(29):16689-16691
对采自武安国家森林公园地衣种类进行了鉴定与分类,初步确定地衣15属21种,其中河北省地衣新记录种1种:裂果双缘衣Diploschistes actinostomus(Pers.)Zahlbr.,并对21种地衣的基物、地理分布特点以及新记录种的形态特征作了初步的讨论。  相似文献   
5.
Abstract

Service life of timber structures in the north of Europe is decreased mainly by biological agents. Increasing risk of biological infestation due to global warming is widely discussed nowadays. Historic timber structures which have been monitored for decades provide us with valuable information on this subject. An investigation of the structures in the Kizhi museum, located in the northwest of Russia was carried out in the 1970s and in 2011–2012. Identification of wood-decay fungi that destroy constructive elements of seventeenth- and nineteenth-century monuments showed that the most frequent damages are caused by brown rot fungi. At the same time, imperfect fungi and ascomycetes which cause soft rot began to play a significant role in damaging historic timber structures. Borers (Hadrobregmus pertinax L. and H. confusus Kraaz) play the leading part in reducing the service life of seventeenth- and nineteenth-century heritage objects. During a forest inventory, some wood-borers not registered previously as timber structure pests in the Kizhi archipelago region (Republic of Karelia, Russia) were found. Twenty-seven species of foliose and fruticose lichens and ten species of crustose lichens were found on the monuments' structural elements.  相似文献   
6.
通过对后河国家级自然保护区地衣资源进行调查,发现湖北省地衣1个新记录属,即癞屑衣属,对应3个湖北省地衣新记录种,分别为膜癞屑衣、灰白癞屑衣、淡蓝癞屑衣并对其形态特征进行了简要描述,为湖北省地衣资源研究和利用提供新资料。  相似文献   
7.
为了查明天山一号冰川岩面生地衣群落主要种群对环境资源的利用特点及其分布格局,沿海拔梯度设立15个样方,利用生态位宽度和生态位重叠指数,分析了30种岩面生地衣的生态位特征,并以生态位重叠值为指标,应用聚类分析和主坐标排序法对它们进行了分类,用最小生成树对其种间关系进行分析。结果表明:大部分的岩面生地衣生态位宽度属于中等偏窄,其中丽石黄衣Xanthoria elegans(Link) Th. Fr.和地图衣Rhizocarpon geographicum(L.) DC.的Shannon-Wiener和Levins生态位宽度指数最大,广泛的分布在研究区不同海拔的各个样方,对环境适应能力强,对群落结构具有重要作用。研究区地衣种对间生态位重叠现象普遍,但大部分重叠值偏低,物种间形成了生态位的分化,且生态位宽度和生态位重叠值之间无明显相关。最小生成树反映了地衣种对间在生境因子上的相似性,与聚类分析和主坐标排序结果一致,将30种岩面生地衣分成3个生态类群。  相似文献   
8.
利用石蜡切片法对岩溶石漠化石面12 种不同小生境的藓类植物茎进行比较解剖学研究。结果表明:12种石生藓类茎的形状、表皮毛、中轴有无和形状以及所占比例等特征因种类不同而存在差异。12 种石生藓类茎的解剖结构表现出表皮细胞排列紧密、细胞壁强烈增厚或增厚明显,1~2 层不等,以1 层居多,较多种类具有向外突起伸长形成多细胞腺体;除沼生真藓未见明显的内外皮层分化外,其余11 种藓类均有内外皮层的分化,外皮部细胞胞壁增厚明显;除小胞仙鹤藓(Atrichum undulatum)和真藓(Bryum argenteum)有明显的中轴分化外,其余8 种石生藓类分化不明显,而短叶小石藓(Weisin semipallida C. Muell.)和穗枝赤齿藓(Erythrodontium julaceum)茎无中轴的分化。说明喀斯特石漠化地区石生藓类对水分吸收和传导以外导水型为主,混合导水型为辅。因此,石生藓类茎的解剖结构特征能反映所处的环境,具有重要的生态适应意义。  相似文献   
9.
以乌鲁木齐南部山区小渠子林场54个样方岩面生叶状地衣调查结果为依据,应用典范对应分析法对群落物种分布与环境参数之间的关系进行了分析。结果表明:小渠子林场岩面生叶状地衣共26种,属于8科、11属、4个目,它们组成了菊叶黄梅+淡肤根石耳+托敏氏褐梅;暗褐梅+膜地卷;网脊平石耳+垫脐鳞衣+皮果衣三个叶状地衣群落。地衣分布与海拔高度、森林郁闭度、大气湿度等有关。人为干扰和基物对岩面生叶状地衣分布的影响不显著。  相似文献   
10.
To date, no global data on carbon sequestration at the initial weathering phase of tephra deposits are available. To study carbon storage in the new volcanic deposit, tephra layers were reconstructed for a period of 46 months. The tephra samples were collected immediately after eruption of Mount (Mt.) Talang on 12 April 2005, over portions of the Solok District in West Sumatra, Indonesia. Pot experiments were filled with and without soil materials and covered with the collected tephra. The pot experiments were conducted in a wired house. The tephra was applied in 0, 2.5 and 5 cm depths to simulate natural tephra deposition. Every day 250 ml of filtered water was added and allowed to percolate. Solid fraction from the tephra layer was collected and analyzed at regular intervals and primary plant succession was observed over a period of 4 years. After 2 months, blue-green algae (cyanobacteria) started to colonize the bare surface tephra layer to form an algae mat. After 16 months, the surface was transformed into a green biofilm of lichen. Vascular plants (grasses and shrubs) started to be established after 2 years. Total carbon (TC) content of the tephra layer was increased significantly from 0.19 to 1.75% or eight times higher after 46 months of incubation. Higher TC storage was found in the 2.5 cm compared to that of the 5.0 cm tephra layer, which was reconstructed above the soil, with values of 1.75 and 0.89%, respectively. On the contrary, lesser amount of TC was accumulated in the single tephra layer (without soil underneath). Between 71 and 90% of TC was considered as total organic carbon (TOC). The labile organic carbon (LOC) content in the 2.5 cm and 5.0 cm of tephra layer was found to be 0.22 and 0.77%, respectively, at the end of incubation. This experiment confirmed the potential of tephra to capture carbon from the atmosphere with the help of nonvascular plants and then by vascular plants and finally sink them in the tephra layer.  相似文献   
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