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51.
The diversity of bryophyte and lichen collections in 9 of the oldest preserved herbaria (dating from ca 1542 to 1577) was compared, including the first reports of bryophytes and lichens from the ‘En Tibi’ herbarium (possibly 1542–1544) and the herbarium of Leonhard Rauwolf (1560–1563). Bryophytes and lichens formed only a minority in each herbarium compared to the numbers of vascular plant specimens; numbers ranged from representatives of 21 genera in the herbarium of Ulisse Aldrovandi to the single genus Conocephalum in the Rauwolf herbarium. The focus was on large, handsome species of bryophytes and macrolichens, apart from small amounts of additional species collected as ‘by-catch’ in mixed collections. All herbaria together included 34 genera of bryophytes (36 species and 10 specimens identified to genus level) and 13 genera of lichens (24 species and 4 specimens identified to genus level). The diversity of mosses was higher than that of liverworts, and pleurocarpous mosses were more diverse than acrocarpous mosses. The collectors probably aimed at selecting material that was either characteristic of the vegetation in the respective areas of collecting or used for certain purposes (or both). The former hypothesis is supported by the small overlap in taxonomic diversity between the herbaria, and the latter by the fact that several moss, liverwort, and lichen genera are included whose traditional uses are well documented.  相似文献   
52.
Abstract

Panbiogeographic track analysis is applied to the distribution of several groups of mosses which occur in the New Zealand region. The analysis highlights areas of biogeographic interest (nodes) in the New Zealand region as follows: 1. New Guinea, 2. New Caledonia, 3. New South Wales/Queensland border in Australia, 4. northern New Zealand, 5. Rapa Island, 6. subantarctic New Zealand.

New Zealand is connected to these nodes by the following standard tracks: 1. New Guinea—New South Wales/Queensland border—Tasmania—subantarctic New Zealand, 2. New Guinea—New Caledonia—New Zealand—subantarctic New Zealand, 3. a central Tasman Sea transversal track; New South Wales/Queensland border—New Caledonia. Rapa Island is connected to the Tasman region by northern New Zealand and New Caledonia.  相似文献   
53.
黔西北两铜矿4种藓类植物重金属元素分析   总被引:2,自引:0,他引:2  
坝口铜矿和长箐沟铜矿是峨眉山玄武岩型铜矿。利用3种光谱仪对卷叶丛本藓(Anoectangium thomso-niiMitt.)、酸土藓[Oxystegus cylindricus(Brid.)Hilp.]、硬叶扭口藓[Barbula rigidula(Hedw.)Mild.]和齿边异齿藓[Regmatodon serrulatus(Dozy et Molk.)Bosch et Lac.]及其基质中的Cu、Zn、Ca、Mg、Cd、Pb、Hg和As8种元素进行测定及分析,并计算出富集系数。结果表明,两铜矿Cu、Zn、Cd和Hg的背景值均超标,特别是Hg和Cu的平均含量分别是其标准值的10.28倍和2.33倍。长箐沟铜矿受Hg污染较重,坝口铜矿比长箐沟铜矿含Cu高。Cu-Cd、Zn-Ca、Ca-Pb和Hg-As均在0.05水平显著相关,Zn-Pb在0.01水平显著相关。Cu-Cd、Zn-Pb和Hg-As均产生协同效应。Zn-Ca和Ca-Pb均产生拮抗效应。富集系数有显著意义。4种藓类植物对Cu、Cd和Pb的吸收能力均是同一水平,可以作为指示植物,构成藓类植物组合来鉴别富集Cu、Cd和Pb的矿区。可利用卷叶丛本藓作为特征植物降低矿区As的污染。  相似文献   
54.
中国藓类植物无性繁殖体的初步观察   总被引:1,自引:0,他引:1  
无性生殖在苔藓植物的生活史中起着重要的作用,并且常通过各种无性繁殖体来完成。无性繁殖体的形态常被用来辅助鉴定一些不育的藓类植物。本文通过对38种藓类植物的无性繁殖体进行显微观察,结果显示:无性繁殖体在不同的藓类植物之间已经过多次演化;无性繁殖体的形态在种内是相对稳定的,且与其着生位置、配子体的分枝方式密切相关,而与植物的系统位置以及生境并无直接的关系;无性繁殖体的颜色与其胞壁的厚度以及表面纹饰密切相关。此外,无性繁殖体的产生常常与假根、原丝体有共存关系。在研究中发现,藓类植物的无性繁殖体主要包括原丝体芽胞、无性芽胞(叶生芽胞、中肋芽胞、枝生芽胞)、芽体、假根芽胞和假根状块茎;其中原丝体芽胞和无性芽胞最为常见。  相似文献   
55.
Representatives of the genus Trachyphyllum are shown to form a monophyletic group. The presence of papillae at both ends of leaf cells, investigated here using SEM, is suggested as a possible synapomorphy. The position of the genus at the family level is discussed and changed to Pylaisiadelphaceae. In addition, the geographic distribution of Trachyphyllum in the New World is updated.  相似文献   
56.
对云南乃古石林出现频度最高的5种藓类植物做了水土保持作用研究。5种藓类植物鳞叶藓(Taxiphyl-lum taxirameum(Mitt.)Fleisch.)、灰白青藓(Brachythecium albicans(Hedw.)B.S.G.)、小牛舌藓全缘亚种(Anomodon minor subsp.integerrimus(Mitt.)Iwats.)、中华细枝藓(Lindbergia sinensis(C.Muell.)Broth.)和拟扁枝藓(Homaliadelphus targionianus(Mitt.)Dix.et P.Varde)的生物量等测定结果显示:平均生物量为24.31~103.78 g/m2,平均饱和吸水率为818.24%~1462.02%,最高的达到1659.27%,最低的也达到了590.95%;平均饱和吸水量为216.92~791.80 g/m2,最高的达到1790.28 g/m2;平均成土率为47.32%~111.58%,最高的达到194.82%,最低的也达到19.33%;平均成土量为9.01~46.73 g/m2,最高的达到110.17 g/m2。小牛舌藓全缘亚种的平均饱和吸水量和平均生物量远远高于其他4种藓类,分别为:791.80 g/m2和103.78 g/m2。相关性分析表明,小牛舌藓全缘亚种的保水成土相关性最显著。它的干重与饱和吸水重、生物量与干重、生物量与饱和吸水量、生物量与成土量、饱和吸水量与成土量都是呈正极显著相关。研究结果表明,在乃古石林剑状喀斯特这种缺少土壤、干旱且保水能力弱的景区环境,藓类植物以其特有的生态功能在石林景观多样性、水土保持等方面具有十分重要的作用。  相似文献   
57.
《Journal of bryology》2013,35(2):339-346
Abstract

Type material is studied for six names of southern hemisphere Racomitria, viz. R. dustro-georgicum Par., R. amoenum (Broth.) Par., R. substenocladum Card., R. skottsbergii Card. et Broth., R. substenocladum fo. *nigrescens Card. et Broth., and R. austro-georgicum var. kranckii Riov. They are all placed as synonyms of R. sudeticum (Funck) Bruch et Schimp., which accordingly is bipolar. Racomitrium austro-sudeticum Broth. in Herz. belongs to the genus Grimmia.  相似文献   
58.
Atewa Forest is a biodiverse tropical forest in the Eastern Region of Ghana, highly threatened by illegal mining, farming and hunting activities, and by proposals for industrial-scale bauxite mining. Conservation bodies are active in trying to save the forest and promote its future as a national park. Very little is known about its bryophyte flora, and this short expedition was intended as a first step to remedy that situation. Survey work in March 2014 was targeted mainly at areas thought likely to be bryophyte-rich, notably swamp forest and upland evergreen forest. A total of 164 species was recorded, including about 58 new to Ghana and at least one new species. The importance of Atewa Forest for biodiversity in western Africa is reinforced.  相似文献   
59.
Six different mosses have been recognised in samples taken from the intestinal contents of the 5,200-year-old Iceman from the Eastern Alps. Four of the species are important in understanding the lifestyle of the man and/or bear on the events during the last few days of his life: Anomodon viticulosus, Hymenostylium recurvirostrum, Neckera complanata and Sphagnum imbricatum. The past and present chorology and habitats of the Hymenostylium are discussed in detail, as is the ethnobotany of the Sphagnum concerning both the Iceman and Kwäday Dän Ts’ìnchí, the first ancient glacier body from North America.  相似文献   
60.
中国藓类植物孢子萌发和原丝体发育的初步研究   总被引:16,自引:2,他引:14  
关于苔藓植物的孢子萌发(Spore Germination)和原丝体发育(ProtonemaDevelopment)的研究,对阐明苔藓植物的各分类群之间的关系和种系发生及系统演化等有重要意义。虽然早在1782年J. Heduing就报告过藓类植物的原丝体形态,但后来长时间内研究较少,直到20世纪50年代开始增多了研究者从事本项工作。到1978年  相似文献   
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