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山旺化石产自临朐县城东22公里的一个名叫“山旺”的小山村,因所产化石种类繁多,保存精美完好而闻名于海内外。早在1980年2月国务院即已批准山旺为国家级重点自然保护区,面积1.2平方公里。1999年10月又被国土资源部、国家环保总局确定为国家地质遗迹保护区。2001年12月,国土资源部又将其批准为国家地质公园。 相似文献
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本研究对国家大豆核心种质在黄淮夏播生态区的农艺性状和适应性进行初步评价和研究,结果认为国家大豆核心种质在黄淮夏播生态区种植农艺性状变异丰富:主要农艺性状的变异系数在11 39%~54 12%之间,结荚高度、有效分枝和单株总荚数的变异系数分别达54 12%、52 50%和51 70%;50%以上的品种有1个或1个以上主要农艺性状与黄淮夏播生态区审定品种近似,部分品种单株荚数超过200个,在育种工作中具有实用价值.各生态类型大豆品种在黄淮夏播生态区的农艺性状与原生态区相比有所改变:除长江春大豆外,东北春大豆、北方春大豆、南方春大豆和南方夏大豆的生育期变异均变小;东北春大豆和北方春大豆的适应性不同,这验证了东北春大豆和北方春大豆是不同生态类型的观点;不同生态类型品种的生育期、株高、百粒重均有一定的改变,株高随着生长坏境的变化较易改变,生育期次之,百粒重表现较稳定.本研究为国家大豆核心种质在该地区的利用提供了参考. 相似文献
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广东石门台亚热带典型常绿阔叶林和亚热带山顶矮林群落特征 总被引:1,自引:0,他引:1
为了研究亚热带典型常绿阔叶林和亚热带山顶矮林的物种组成和群落结构,在广东石门台国家自然保护区内分别建立了1 hm2亚热带典型常绿阔叶林样地和1 hm2亚热带山顶矮林样地,以样地内所有胸径(DBH)≥1 cm的乔木、灌木和藤本为研究对象,分析两种森林类型的物种组成、密度、径级和株高结构。结果显示:(1)两种森林的Srensen物种相似性指数为0.41,优势种不同,但优势科却较相似;其中,茶科和杜鹃花科在两种森林中所占比例较高;(2)亚热带典型常绿阔叶林的幼苗(1 cm≤DBH〈2.5 cm)和幼树(2.5 cm≤DBH〈12.5 cm)密度都显著小于亚热带山顶矮林,但两种森林的小树(12.5 cm≤DBH〈25 cm)和大树(DBH≥25 cm)密度均无显著差异;亚热带典型常绿阔叶林幼苗和大树的平均胸径都显著大于亚热带山顶矮林,而幼树的平均胸径则显著小于亚热带山顶矮林,小树的平均胸径无显著差异;亚热带典型常绿阔叶林中小树和大树的平均高度都显著大于亚热带山顶矮林,而幼苗的平均高度显著小于亚热带山顶矮林,幼树的平均高度无显著差异。综合分析表明,亚热带典型常绿阔叶林和亚热带山顶矮林的物种组成、密度、胸径和高度结构差异较大,亚热带典型常绿阔叶林群落稳定性强于亚热带山顶矮林。 相似文献
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正贡嘎山位于四川省康定以南,是大雪山的主峰。周围海拔6000米以上的山峰有45座,主峰更耸立于群峰之巅,海拔7 556米,高出其东侧大渡河6 000米,被喻为"蜀山之王"。特定的地理环境和特殊的气候条件,形成了多层次的立体植物带和特有的自然景观。海拔5 000米以上的山峰,终年积雪;低海拔、无人烟的坡麓地带森林密布,郁郁葱葱,生态环境原始。这里的森林受人类活动的影响小,植被完整,几乎拥有从亚热带到高山寒带能生存的所有植物物种。珍稀植物种类繁多,拥有植物4 880余种,属国家保护的珍稀物种达400余种。而栖息在这里的野生动物达400余种,珍稀保护动物有28种,堪称世界野生动植物的大观园。 相似文献
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《植物生态学报》2014,38(6):576
Aims An understanding on the living communities of the state’s key protected wild plants and the ability in utilizing resources and occupying ecological spaces by different populations is essential to the protection and propagation of rare and endangered plant species. We use our findings to highlight the knowledge gaps in the conservation strategies for the endangered species.
Methods Field investigations were conducted during 2009-2011. Based on the survey data on 70 forest plots in the Bawangling protected area, the niche breadths and overlaps of 12 species listed as the state’s key protected plants were calculated and analyzed.
Important findings The 12 species, by their niche breadth values in descending order, include Aquilaria sinensis, Nephelium topengii, Camellia sinensis var. assamica, Alseodaphne hainanensis, Keteleeria hainanensis, Podocarpus imbricatus, Firmiana hainanensis, Parakmeria lotungensis, Cephalotaxus mannii, Michelia hedyosperma, Ixonanthes reticulata, Dacrydium pierrei. The niche breadth value of a species is closely related to its range of geographical distribution; both Dacrydium pierrei and Parakmeria lotungensis had a narrow niche breadth corresponding to their narrow ranges of altitudinal distribution. In general, the niche overlap value is higher between species with greater niche breadth; the highest niche overlap value of 0.872 was found between Camellia sinensis var. assamica and Keteleeria hainanensis. However, the niche overlap value between species with smaller niche breadth could also be high; e.g. the niche overlap value was relatively high (0.693) between two species with smaller niche breadth, Michelia hedyosperma and Firmiana hainanensis, indicating that niche overlap value is dependent upon the biological characteristics and requirements for environmental resources of the species of comparison. Some species with low niche breadth values (e.g. Michelia hedyosperma and Ixonanthes reticulata) were found to have smaller populations. Due to lack of suitable community and habitats, these plant species are in dire need of more attention and prioritization for conservation. In conclusion, for the better protection and propagation of these endangered plants in the future, we should combine knowledge of their biological characteristics with that of their living communities such as the montane rainforests, etc. 相似文献
Methods Field investigations were conducted during 2009-2011. Based on the survey data on 70 forest plots in the Bawangling protected area, the niche breadths and overlaps of 12 species listed as the state’s key protected plants were calculated and analyzed.
Important findings The 12 species, by their niche breadth values in descending order, include Aquilaria sinensis, Nephelium topengii, Camellia sinensis var. assamica, Alseodaphne hainanensis, Keteleeria hainanensis, Podocarpus imbricatus, Firmiana hainanensis, Parakmeria lotungensis, Cephalotaxus mannii, Michelia hedyosperma, Ixonanthes reticulata, Dacrydium pierrei. The niche breadth value of a species is closely related to its range of geographical distribution; both Dacrydium pierrei and Parakmeria lotungensis had a narrow niche breadth corresponding to their narrow ranges of altitudinal distribution. In general, the niche overlap value is higher between species with greater niche breadth; the highest niche overlap value of 0.872 was found between Camellia sinensis var. assamica and Keteleeria hainanensis. However, the niche overlap value between species with smaller niche breadth could also be high; e.g. the niche overlap value was relatively high (0.693) between two species with smaller niche breadth, Michelia hedyosperma and Firmiana hainanensis, indicating that niche overlap value is dependent upon the biological characteristics and requirements for environmental resources of the species of comparison. Some species with low niche breadth values (e.g. Michelia hedyosperma and Ixonanthes reticulata) were found to have smaller populations. Due to lack of suitable community and habitats, these plant species are in dire need of more attention and prioritization for conservation. In conclusion, for the better protection and propagation of these endangered plants in the future, we should combine knowledge of their biological characteristics with that of their living communities such as the montane rainforests, etc. 相似文献
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斑马鱼是一种新兴的脊椎模式动物。在过去的30年中,斑马鱼已被广泛应用于生命科学、健康科学、环境农业等诸多科研领域。为了满足不同的科研需要,研究人员开发和利用各种技术创建了大量的斑马鱼基因突变和转基因品系,这些品系已成为开展相关科学研究的宝贵资源。为了更好地保藏和利用这些资源,在全球范围内建设有多个规模不一的斑马鱼资源库。2012年,我国的国家斑马鱼资源中心(http://zfish.cn)在中国科学院水生生物研究所正式成立。本文将重点介绍全球斑马鱼资源的开发和保藏情况,以及我国国家斑马鱼资源中心的最新建设进展。 相似文献