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广西亚热带酸性土丘陵山地草丛的群落学特点及其合理利用的方向 被引量:1
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作者 王献溥 胡舜士 《自然资源学报》 1986年第1期65-78,共14页
我国亚热带酸性土丘陵山地,当常绿阔叶林或山地常绿、落叶阔叶混交林被采伐以后,在采伐迹地上遭火烧的情况下,无论垦殖与否,都会出现大片的以禾本科草类或蕨类植物占优势的草丛。如果连年都遭受火烧,它就能保持稳定,成为所谓的火烧顶极... 我国亚热带酸性土丘陵山地,当常绿阔叶林或山地常绿、落叶阔叶混交林被采伐以后,在采伐迹地上遭火烧的情况下,无论垦殖与否,都会出现大片的以禾本科草类或蕨类植物占优势的草丛。如果连年都遭受火烧,它就能保持稳定,成为所谓的火烧顶极。一旦火烧停止,阳性乔灌木树种就会迅速侵入,几年之后就会发展成为灌丛,并向森林的方向发展。热带许多地方的情况也是这样。毫无疑问。 展开更多
关键词 地面芽植物 群落学特点 亚热带 高位芽植物 重要值指数 丘陵山地 合理利用 地下芽植物 酸性土 野古草
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破碎化景观格局中热带干旱森林的结构、多样性与保护价值
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作者 Oscar R.Lanuza Fernando Casanoves +3 位作者 Sergio Vílchez-Mendoza Josep Maria Espelta Josep Peñuelas Guille Peguero 《Journal of Plant Ecology》 SCIE CSCD 2023年第1期163-176,共14页
尽管热带干旱森林是世界上退化和破碎化程度最严重的生物群落之一,但我们对它们的基本生态特征和保护状况仍然知之甚少,尤其是在新热带地区。在本研究中,我们对尼加拉瓜破碎化景观格局中的热带干旱森林的多样性、组成、结构和保护价值... 尽管热带干旱森林是世界上退化和破碎化程度最严重的生物群落之一,但我们对它们的基本生态特征和保护状况仍然知之甚少,尤其是在新热带地区。在本研究中,我们对尼加拉瓜破碎化景观格局中的热带干旱森林的多样性、组成、结构和保护价值进行了评估。我们在河流廊道、次生林、绿篱和林间牧地之中和沿线地区建立了31处样地和样带。我们使用希尔数(Hill number)对胸高处直径≥2.5 cm的所有树木进行了记录,并对每种森林类型中树木的丰富性和多样性进行了估算,接着计算了种级分类和科级分类上的重要值指数(Importance Value Index,IVI),最后则使用Bray-Curtis相似性指数进行了非度量多维标度(Non-Metric Multidimensional Scaling,NMDS)排序和相似性分析(Analysis of Similarities,ANOSIM)。不同森林类型之间在多样性上存在差异,但物种丰富度却不存在差异。豆科植物的IVI值最高,其次是桑科植物和锦葵科植物。Vachellia pennatula、Guazuma ulmifolia和Bursera simaruba的IVI值都>30%,其中前两种是所有森林类型中最为丰富的树木。对群落的相似性进行分析后可知每种森林类型都有着不同的组成,从而凸显了对所有这些不同类型的土地覆盖开展保护的重要性。 展开更多
关键词 豆科植物 破碎化 希尔数(Hill number) 重要值指数 河流廊道 热带干旱森林
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Comparative regeneration status in a natural forest and enrichment plantations of Chittagong (south) forest division, Bangladesh
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作者 M. Kamal Hossain M. Lutfor Rahman +1 位作者 A. T. M. Rafiqul Hoque M. Khairul Alam 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期255-260,共6页
The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat metho... The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference. 展开更多
关键词 REGENERATION Natural forest Enrichment plantations Relative density Frequency ABUNDANCE Importance Value Index
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