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61.
江西三清山珍稀濒危植物考察研究 总被引:9,自引:1,他引:8
三清山有珍稀濒危植物33种,隶属30属22科,其中蕨类植物1科1属1种,裸子植物6科12属12种;被子植物15科17属20种。主要讨论了三清山珍稀濒危植物地理分布及保护。 相似文献
62.
鹅掌楸(Liriodendron chinense(Hemsl.) Sarg.)是中国特有珍稀树种.鉴于目前还鲜有野生鹅掌楸组培过程生理生化变化的相关报道.本研究以峨嵋山野生鹅掌楸茎尖芽为外植体进行组织培养,并对其继代培养再生过程中超氧阴离子自由基(O_2~-)、过氧化氢(H_2O_2)和丙二醛(MDA)含量的变化进行了测定.研究结果表明,随着培养时间的延长,植物体中O_2~-和MDA含量呈现逐渐增加的变化趋势.这表明在连续继代培养条件下,植物体内活性氧会积累,引起膜脂过氧化.H_2O_2含量"S"形曲线变化,并随着再生芽的分化而上升,因此,H_2O_2不仅参与了膜脂过氧化过程,还可能作为一种细胞信号物质参与诱导细胞分化和再生芽的形成.该研究也为进一步用组织培养法保存峨眉山珍稀植物鹅掌楸种质资源提供了参考. 相似文献
63.
该文以福建武夷山亚热带常绿阔叶林为研究对象, 通过设置3个氮(N)添加梯度的野外实验, 研究了群落内乔木植物、灌木植物、草本植物、蕨类植物和苔藓植物叶片N、磷(P)化学计量特征对N沉降的响应, 以及不同功能群和物种化学计量特征对N沉降响应的差异。在已开展5年人工N添加的样地内, 3年的监测结果表明: N添加整体上提高了植物叶片N含量, 草本层植物叶片N含量对N添加的响应比乔木层和灌木层植物更加敏感, 优势种米槠(Castanopsis carlesii)、草本植物砂仁(Amomum villosum)、蕨类植物狗脊(Woodwardia japonica)的叶片N含量显著增加。N添加整体上增加了植物叶片P含量, 乔木层植物和灌木层植物叶片P含量没有显著变化, 草本层植物叶片P含量显著增加, 而苔藓植物叶片P含量显著减少。N添加促使武夷山亚热带常绿阔叶林植物叶片N:P由18.67上升至19.72, 加剧了植物生长的P限制; 乔木物种N:P的变化较灌木和草本物种更加稳定。N添加条件下, 植物叶片N:P的变化主要受到叶片P含量而非N含量变化的影响, N添加对生态系统P循环的影响显著。 相似文献
64.
Aaron Sell Daniel Sznycer Leda Cosmides John Tooby Andre Krauss Silviu Nisu Cristina Ceapa Michael Bang Petersen 《Evolution and human behavior》2017,38(3):334-340
There is substantial evidence from archaeology, anthropology, primatology, and psychology indicating that humans have a long evolutionary history of war. Natural selection, therefore, should have designed mental adaptations for making decisions about war. These adaptations evolved in past environments, and so they may respond to variables that were ancestrally relevant but not relevant in modern war. For example, ancestrally in small-scale combat, a skilled fighter would be more likely to survive a war and bring his side to victory. This ancestral regularity would have left its mark on modern men's intergroup psychology: more formidable men should still be more supportive of war. We test this hypothesis in four countries: Argentina, Denmark, Israel, and Romania. In three, physically strong men (but not strong women) were significantly more supportive of military action. These findings support the hypothesis that modern warfare is influenced by a psychology designed for ancestral war. 相似文献
65.
Competition and facilitation may lead to asymmetric range shift dynamics with climate change 下载免费PDF全文
Forecasts of widespread range shifts with climate change stem from assumptions that climate drives species' distributions. However, local adaptation and biotic interactions also influence range limits and thus may impact range shifts. Despite the potential importance of these factors, few studies have directly tested their effects on performance at range limits. We address how population‐level variation and biotic interactions may affect range shifts by transplanting seeds and seedlings of western North American conifers of different origin populations into different competitive neighborhoods within and beyond their elevational ranges and monitoring their performance. We find evidence that competition with neighboring trees limits performance within current ranges, but that interactions between adults and juveniles switch from competitive to facilitative at upper range limits. Local adaptation had weaker effects on performance that did not predictably vary with range position or seed origin. Our findings suggest that competitive interactions may slow species turnover within forests at lower range limits, whereas facilitative interactions may accelerate the pace of tree expansions upward near timberline. 相似文献
66.
67.
鼎湖山人工松林生态系统蒸散力及计算方法的比较 总被引:9,自引:0,他引:9
Based on the consecutive measurement (1995-1997) of meteorology and microclimate of artificial Pinus forest in Mount Dinghu, we calculated the potential evapotranspiration by using four different methods to discuss the method which is fit for forest ecosystem. The results are given as follows.1) In terms of the enviromental conditions of forest ecosystem, we redefined some parameters in Penman equation and used it to calculate the potential evapotranspiration of artificial Pinus forest ecosystem in Mount Dinghu.Preliminary result is that Penman equation is worth spreading for calculating the potential evapotranspiration of forest ecosystem,compared with several other methods.2) The annual average potential evapotranspiration of the artificial Pinus forest in Mount Dinghu is 937.55mm,according to Penman equation. It is 50% of the rainfall in the corresponding period. The highest mean monthly potential evapotranspiration is July and the lowest mean monthly potential evapotranspiration is January. This is completely consistent with the variations of temperature. 相似文献
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69.
JARLE W. BJERKE HARRIE J. M. SIPMAN 《Botanical journal of the Linnean Society. Linnean Society of London》2007,153(4):489-499
The genus Menegazzia (Parmeliaceae, lichenized ascomycetes) in Malaysia and Indonesia is studied. Some specimens from Papua New Guinea are also included. The great majority of available specimens are from Kinabalu Park, State of Sabah, Malaysia. Three species are described as new to science, namely the two sorediate species M. capitata (from Sabah and Pahang in Malaysia) and M. sabahensis (from Sabah), and the fertile, primary species M. monospora (from Sabah and Papua New Guinea). M. asahinae , M. dissoluta , and M. efflorescens are reported for the first time from Malaysia, and M. subsimilis is reported for the first time from Malaysia and Indonesia. The subgenus Megamenegazzia is newly described to accommodate the large, broad-lobed species with numerous perforations on the lower surface. M. efflorescens is selected as the type species for the new subgenus. Notes are also provided on the type specimens of Hypogymnia pectinatula , a species originally considered as belonging to Menegazzia . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 489–499. 相似文献
70.
生态系统文化服务(CES)的核心是人与自然之间的情感连接,利益相关者视角下的参与式制图是感知与保护热点文化服务地区的有效方法。采用参与式制图与访谈、问卷相结合的方式调查了游客和居民2类群体对武夷山市CES的感知情况;利用空间分析、热点分析和相关性分析比较分析了游客和居民CES的感知差异特征、影响因素及其空间分布格局。结果表明:(1)除了居民月收入对感知有影响外,游客和居民对武夷山市CES认知基本不受人口学特征(性别、年龄、职业和文化程度)的影响(P>0.05);(2)居民的CES价值人均支付保护意愿较游客高。文化遗产、游憩与生态旅游、教育、美学价值是游客和居民都重视的4类子文化服务。游客对文化遗产价值服务的支付意愿最高,而居民则对教育价值服务支付意愿最高。(3)居民对CES价值感知分布空间范围较广,几乎涵盖了武夷山市大部分乡镇;而游客则相对集中,主要位于旅游点密集区域,对其他地区的感知程度较低。CES价值冷热感知程度与旅游点分布呈现相同的空间分布格局,游客和居民对CES价值热点区的感知强度从南向北逐渐降低。(4)从不同文化服务类型权衡/协同关系上看,除了“精神与宗教价值”和“游憩... 相似文献