濒危植物厚叶木莲的群落学特征及其保护

根据从化三角山次生常绿阔叶林的样方调查结果,分析了中国特有植物厚叶木莲（ManglietiapachyphyllaChang）的天然分布特点,分布区的自然环境概况,群落的区系特点,群落学特征及其保护策略．厚叶木莲仅零散分布于广东从化三角山、龙门南昆山和新丰小沙罗等地海拔650－1000m的常绿阔叶林中,分布区非常狭窄．在1200m~2的样地里有维管植物132种,隶属于57科89属。Shannon－Wiener物种多样性指数为5．45,均匀度为84．39％,类似于其他类群的南亚热带常绿阔叶林,但较低于海南的热带雨林类群．本群落植物区系的分布类型是以泛热带分布和热带亚洲分布两大类为主,热带－亚热带区系植物成分在本群落中占有明显的优势,其区系特点具有从热带向亚热带过渡的性质．该群落命名为赤楠、假轮叶虎皮楠、厚叶木莲群落,可分为乔木层（2亚层）、灌木层及草本层等层次．本群落以中、小高位芽植物占优势,缺乏大高位芽、地面芽和一年生植物,叶型以中型叶为主．种群分布格局分析表明,大部分优势种呈集群分布,其中厚叶木莲呈集群分布。种群的立木结构分析表明,厚叶木莲种群已处于衰退模式,有即将在群落中消失的可能,属于濒危物种,应加以保护,对厚叶木莲及其群落的保护应立足于就地保护．     

珍稀植物华木莲的现代濒危机制:探析与展望

华木莲(Sinomanglietia glauca)在探讨木兰科系统演化与被子植物起源等方面具有重要科学价值,但其分布区域狭窄、种群规模较小,被列为我国濒危植物和极小种群植物。该文在系统综述华木莲生物生态学特性和更新维持机制的基础上,对华木莲的现代濒危原因进行了总结:(1)华木莲属古老残遗濒危植物,环境变迁、瓶颈效应、高频自交和遗传漂变,导致其遗传多样性下降、适应性差;(2)喜光喜肥的生物生态学特性和群落种间竞争驱赶作用,"林—窗"游击式更新是华木莲种群延续的重要方式,然而当前人类干扰导致有效林窗供给不足、种子传播效率下降、"游击"机会减少,更新难以完成;(3)毛竹扩张与林下箬竹过度增长严重影响华木莲开花结实,并妨碍其幼苗更新。今后应加强华木莲谱系地理与群落系统发育、群落环境对华木莲生长发育的影响及其应答、林窗更新机制与种子长距传播、群落结构调整与保护技术、遗传复壮与迁地保护等方面研究,为华木莲以及相似生物生态学特征的濒危植物保护提供理论指导。     

海南文昌维管植物区系特征分析

采用全面踏查结合文献研究的方法,对海南文昌地区维管植物组成、区系成分、分布区类型进行了研究。结果显示,文昌地区共计有维管束植物201科777属1397种,其中蕨类植物31科46属67种,种子植物170科731属1330种;野生种子植物634属1183种(包括珍稀濒危植物25种,海南特有种49种)。在属级水平上,文昌植物区系以热带成分占绝对优势,热带、亚热带成分占非世界分布总属数的93.23%。在种级水平上,热带亚洲成分和中国特有成分是该地区植物区系的主要组成部分,其中热带亚洲分布及其变型的分布种最多,占非世界广布种的47.26%;中国特有种占非世界广布种的12.01%。此外,村落风水林保存了大量当地珍稀植物和古树名木,对当地生物多样性保护具有重要意义,建议当地政府加强对村落风水林的保护。     

亚热带常绿阔叶林和暖温带落叶阔叶林叶片热值比较研究

植物干重热值(GCV)是衡量植物生命活动及组成成分的重要指标之一,反映了植物光合作用中固定太阳辐射的能力。利用氧弹量热仪测定了亚热带和暖温带两个典型森林生态系统常见的276种常见植物叶片的干重热值,探讨了亚热带和暖温带植物热值分布特征,以及不同生活型、乔木类型间植物热值的变化规律。实验结果发现:亚热带常绿阔叶林和暖温带落叶阔叶林叶片热值的平均值分别为17.83 k J/g(n=191)和17.21k J/g(n=85),整体表现为亚热带植物暖温带植物。不同地带性植被的植物叶片热值在不同生活型间表现出相似的规律,其中亚热带常绿阔叶林表现为:乔木(19.09 k J/g)灌木(17.87 k J/g)草本(16.65 k J/g);暖温带落叶阔叶林表现为:乔木(18.41 k J/g)灌木(17.94 k J/g)草本(16.53 k J/g);不同乔木类型间均呈现常绿乔木落叶乔木、针叶乔木阔叶乔木的趋势。落叶阔叶乔木表现为亚热带暖温带,而常绿针叶乔木则呈现亚热带暖温带的趋势。此外,我们对于两个分布区域内的4种针叶树种叶片热值进行了比较,发现华北落叶松(19.32 k J/g,暖温带)杉木(19.40 k J/g,亚热带)马尾松(19.82 k J/g,亚热带)油松(20.95 k J/g,暖温带)。亚热带常绿阔叶林和暖温带落叶阔叶林植物热值的特征及其变化规律,为森林生态系统的能量流动提供了理论基础。     

广东省沙溪自然保护区植被资源与分布

文章通过对沙溪自然保护区的植物资源调查,对保护区的植被类型进行了分类,并对野生植物资源的种类的分布进行了分析.调查发现保护区有7种植被类型,其中以亚热带常绿阔叶林为主要植被类型,主要分布于海拔100~850m左右的丘陵和山地.亚热带常绿针叶与阔叶混交林面积较大,主要分布在长坪一带.亚热带常绿与落叶阔叶混交林、亚热带常绿针叶林、灌丛草坡分布较少.竹林主要在村庄附近的沟谷两旁和山地,处于半自然状态.保护区野生维管植物191科630属1225种,其中野生国家级保护植物7种,珍稀野生保护植物7种.保护区内植物资源丰富,其中野生维管植物资源种类繁多,蕴藏量较大,不少种类具有巨大的经济价值和生态价值,这对保护区及北江流域生态环境的保护和改善提供了基础依据.     

中国野生凤仙花属物种多样性和地理分布数据集

凤仙花属(Impatiens)植物主要分布于旧世界的热带和亚热带山区, 对生长环境要求极度严苛, 深入分析其地理分布格局与特征, 可为种质资源调查和利用提供理论依据。本研究通过系统检索文献资料, 更新了该属植物物种名录, 整合其地理分布、海拔、特有性等信息, 建立了中国野生凤仙花属植物地理分布数据库。截至2022年3月, 中国共记载野生凤仙花属植物352种(包含18变种1亚种1变型), 其中中国特有种273种。除上海市外, 中国其他各省级行政区均有野生凤仙花属植物分布, 其中云南省分布有165种, 其次为四川省(119种)和西藏自治区(69种)。县级尺度上, 贡山独龙族怒族自治县和腾冲市以51种并列物种丰富度第一, 其次是福贡县(42种)。中国野生凤仙花属的分布总体呈现以热带、亚热带为中心向高纬度和高海拔区域扩散的格局, 广义横断山区、西藏南部地区、滇黔桂喀斯特区域、长江中下游等地为凤仙花属植物集中分布的热点地区。     

亚热带八个阔叶林内不同分布型植物的性状和生态习性差异

组成我国亚热带地区植被的植物区系来源多样。为了解共同生活在该地区的不同区系成分间在生态位上存在何种差异，以提高对该地区生物多样性维持机制的认识，该研究以中国亚热带地区8个阔叶林动态样地内木本被子植物群落为研究对象，通过采用谱系线性回归和方差分析(ANOVA)等统计方法，分析了温带和热带分布型属植物在生活史性状(叶习性和生长型)和生态习性(Ellenberg生态指示值)上的差异。结果表明：(1)对于涉及的265个属，分布型属具有一定的谱系保守性(Pagel’s λ=0.935,P<0.001)。(2)温带分布型属含落叶阔叶植物和乔木较多，热带分布型属则以常绿阔叶植物和灌木为主。(3)与热带分布型属植物相比，温带分布型属植物所处环境具有较强光照、较低温度和湿度，且在控制了叶习性和生长型的影响后，两者间的生态习性差异仍然存在。(4)对于所有植物，或者对于不同叶习性和生长型功能群而言，温带与热带分布型属植物的相对优势(物种数的比值)均受到年平均气温的影响。该研究结果有助于理解区系来源对亚热带阔叶林内木本被子植物的生活史性状和生态习性均具有重要影响，以及不同区系来源的植物在我国亚热带阔叶林...     

三种濒危木兰植物幼树光合特性对高温的响应

以3种木兰科濒危植物香木莲、大叶木莲及大果木莲为试材,利用LI-6400便携式光合作用测量系统、叶圆片氧电极仪及叶绿素荧光仪,在夏季对其气体交换特性及叶绿素荧光参数等进行了测定.结果表明,3种木兰幼树叶片净光合速率(Pn)的日变化曲线呈双峰型,第1个峰出现在08:00,第2个峰出现在14:00～16:00,12:00有明显的光合"午休"现象.3种木兰植物的最大净光合速率(Pmax)为5.2～7.4μmolm-2s-1 ,光补偿点(LCP)为14～17 μmolm-2s-1 ,光饱和光强(LSP)为500～800μmolm-2s-1,大叶木莲的Pmax、LSP和表观量子产额(AQY)显著高于香木莲和大果木莲.随着温度升高,3种木兰植物光合放氧速率先升后降,最适温度为35℃,香木莲的放氧速率显著低于大叶木莲和大果木莲.短期高温胁迫下(45～50℃)3种木兰植物的PSⅡ最大光化学效率(Fv/Fm)均明显降低,初始荧光(F0)升高,大叶木莲的Fv/Fm降幅和F0的升幅均显著低于香木莲和大果木莲.3种木兰植物的光合速率和耐高温能力的顺序为大叶木莲＞大果木莲＞香木莲.     

我国亚热带天然森林的开发与保护问题

森林在生物圈生态平衡上有举足轻重的位置,然而人类文明历史的发展却导致大面积原生型森林的毁灭。我国亚热带原生型森林以常绿阔叶林为代表,分布地域广,植物区系独特,珍稀古植物多,经济植物资源丰富且利用潜力大,是巨大的生物宝库。本文初拟了我国中亚热带分布较广的主要原生型森林类型,并引实例论述了这些原生型森林在近30年来受到极大破坏以及这类森林被破坏后造成的严重后果,最后提出了若干保护措施和建议,呼吁社会重视对我国亚热带自然资源的保护,以确保我国亚热带较完好的生态系统,为子孙后代造福。     

秦岭藓类植物区系特点与地理分布的初步研究

本文研究了:1.秦岭藓类植物水平分布与这一地区森林分布的格局是相一致的。垂直分布以北坡为例可划分为5个带;海拔2400—2900米是白齿藓属(Leucodon)种分化特别活跃的一带,作者认为秦岭地区可能是该属植物的分布中心和分化中心亦或是起源地;2.秦岭藓类138属中,热带和亚热带的属有21个,而且其中有14属仅各有1种,其它各属均为2—3种。这充分证明,秦岭南坡已是亚热带藓类分布的北部边缘。秦岭有80个属为温带属,在秦岭藓类植物中占有显著地位,这也充分说明秦岭藓类植物的地理成分是以温带为主,也就是泛北极区系成分为主;3.园枝藓属(Pterogonium)和拟直毛藓属(Kiaeria)是新分布于中国的属;4.秦岭藓类植物区系与我国西藏、东北两地藓类植物区系的关系。     

The Phytoeoenological Features of Mixed Evergreen and Deciduous Broadleaf Forest on Yellow-brown Soil Mountain in Guangxi

The mixed evergreen and deciduons broadleaf forest on yeIlow-brown soil mountain belongs to climax vegetation type in humid subtropics. Analysis of its phytocoenological features shows that its physiognomy is characterized by leathery and herbaceous, simpie-leaved, microphyllous and mesophyllous types of evergreen broadleaf phanerophytes and deciduous broadleaf phanerophytes. As the structure of the community, from the aerial top to the forest floor, there are three distinct layers, namely, the tree layer, the shrub layer and the herbaceous layer. Moreover, the tree layer can be subdivided into three sublayers. Synusia structure is considerably complex, and there are different dominant synusia in each layer. The epiphytes and liana are not as abundant as that of seasonal rain forest. Floristic composition of the community is dominanted by endamic chinese subtropical plant species and East Asian elements. This condition indicates that it can be considered as a special vegetational type of humid chinese subtropics. Analysis of population in the community shows that most of the edificators have different age groups indicating normal reproduction of saplings and seedlings. This means that the habitat is suitable for their growth and reproduction during a certain duration of time. The community will be able to maintain its relative stable status. However, such a forest area is not large, and it is necessary to be protected intensively. Many kinds of rare plants in this forest, for example, Fagus lucida, Fagus longipetiolata, Cyclobalanopsis multinervis, Pseudosassafras tsumu, Manglietia fordiana, Manglietia chingii, Michelia maudiae, Castanopsis lamontii, Schima argentea, Pterostyrax leveillei etc. are worth mentioning.     

中国木兰科11属40种植物的核形态研究

为了探讨木兰科属间系统学关系和一些种的分类学地位,对中国木兰科11属40种进行了核形态研究。所研究的20种木莲属植物都为二倍体,表明木莲属植物主要是在二倍体水平上进化的,不同的种类具有各自的遗传组成,细微的染色体结构变异可能导致种间形态发生了明显的变化。木兰属的染色体数目具多样性,表明属内存在着不同倍性水平上的进化,说明木兰属分布广泛、形态复杂多样有其细胞学基础。细胞学证据支持木莲属应为独立的属,不宜于归并到木兰属。已观察的含笑属都为二倍体,而木兰属玉兰亚属的大多数种类为多倍体。我们认为维持现有的含笑属的分类地位和范围是恰当的,不支持将含笑属和玉兰亚属合并为一属。拟单性木兰属都是多倍体。木兰科植物形态特征重叠,性状呈网状进化,细胞学证据在探讨一些大属属下种的分类地位时具有一定价值,但论及整个科的分类系统和属间亲缘关系时,作用比较微弱。本文在细胞学基础上,结合形态和地理分布,重点对木莲属一些种类的分类地位进行了讨论。     

Comparative Anatomical Studies on the Vessel Elements of Eight Genera in Magnoliaceae

This paper deals mainly with comparative studies on vessel elements of secondary xylem in Chinese Manglietia, Manglietiastrum, Alcimandra, Parakmeria, Paramichelia, Tsoongiodendron, Aromadendron and Liriodendron. There are some differences between the genera in vessel element length and width. Manglietia species all have scalariform perforation plates, only a few also have simple perforations. The other genera have scalariform perforation plates. only one (Tsoongiodendron odorum Chun) has simple perforations in addition. There are no spiral thickenings in Manglietia except for one species [Manglietia chingii Dandy (M. temuipes Dandy)] . Paramichelia and Liriodendron have no spiral thichenings, but they are present in the other genera. In addition, some other differences in vessel elements between these 8 genera are also discussed.     

Diversity and evenness of Hemiptera communities on naturally vegetated derelict land in NW England

Samples of Hemiptera were collected at sixteen naturally vegetated derelict sites using both suction apparatus and beating bags Sample sites were chosen to provide a broad range of vegetation types, representing changes in successional stage and soil pH Hemipteran diversity indices were significantly correlated with site area, but not with soil pH or site age Vegetation species diversity and evenness indices were not significantly correlated with site age, area or soil pH Hemipteran and vegetation evenness (using both Shannon evenness, J, and Heip's evenness, F₁₀) were significantly correlated Similar evenness correlations were found when sub-order Homoptera and vegetation were compared No significant correlations were found between the diversities of sub-order Heteroptera and vegetation Factors determining Hemiptera and vegetation diversity on these sites are discussed It is suggested that rare plant species are of importance in determining the presence of rare species of Hemiptera on the sites It is proposed that diversity as a concept is of most value in ecological studies when its two components, species richness and evenness are considered separately     

Manglietia guangzhouensis sp. nov. (Magnoliaceae) from Guangdong, China

Manglietia guangzhouensis A. Q. Dong, Q. W. Zeng & F. W. Xing, a new species of Magnoliaceae from Guangdong province, China, is described and illustrated. It is closely related to M. pachyphylla H. T. Chang, but differs primarily in its brown villose lower surface of leaves, brown tomentose and stout brachyblasts (peduncles), absence of pedicels, sparsely brown pubescent outer tepals and more numerous ovules (12–14) in each carpel. It is a very rare species with a highly restricted distribution.     

Montane outcrop vegetation of Banks Peninsula, South Island, New Zealand

Species composition patterns and vegetation?environment relationships were quantified for montane volcanic outcrops on Banks Peninsula. The flora of these habitat islands comprises 346 vascular plant species including 82 exotic species and 52 species that are nationally rare, regionally rare, or regional endemics. Both MDS ordination analysis and TWINSPAN results illustrated the high compositional and environmental heterogeneity across the outcrops. Multi-dimensional scaling revealed that primary environmental factors related to community composition comprise both regional-scale gradients of altitude and outcrop-scale gradients of slope steepness, soil pH, area available to plants, maximum vegetation height, and the percentage of the surrounding vegetation that is forest. Accordingly, TWINSPAN separated four outcrop communities that occur on steeper slopes, have less fertile soils and tend not to face north from three outcrop communities that have shallower slopes, more fertile soils and tend to face north. Types in the first group are more likely to be bordered by forest or taller shrublands, whereas those in the second group occur on outcrops primarily bordered by grasslands and support more exotic species. Within these broader groups, communities differ in their altitude and the size, soil depth and shading of the outcrops on which they occur. We describe the vegetation of the seven communities; this ranges from predominance of stunted trees and taller statured species such as Podocarpus hallii and Phormium cookianum to vegetation of shrubby species such as Heliohebe lavaudiana and Hebe strictissima, to short vegetation of native woodland and grassland species such as Polystichum vestitum and Rytidosperma corinum, to exotic pasture of clovers and exotic grasses. The percentage of species on an outcrop face that are exotic is well modelled by site factors, with exotics increasing as the surrounding matrix becomes more disturbed, slopes become more gentle, the percentage of shade on the outcrop decreases, and soil fertility increases. In contrast, nearby disturbance has little influence on the percentage or number of species that are rare on an outcrop face; rather rare species richness is more strongly related to outcrop area and lack of shade, echoing patterns observed for rare outcrop species elsewhere in the world. These results highlight the importance of considering the high compositional heterogeneity among outcrops and the influence of disturbance to surrounding ecosystems in guiding conservation planning.     

Changes in hydraulic traits of nine vascular plants from different evolutionary lineages北大核心CSCD

Aims As vascular plants evolve from ferns to gymnosperms and angiosperms, their physiological structures and functions are assumed more adaptable to arid environment. Whether the three plant groups from early to late evolved lineages have improved their water transport and use efficiency has been studied on the basis of the morphological structure of leaf veins and stomata.Moreover, the water transportation rate was directly measured in the angiosperms. Therefore, we measured structural and functional traits related to water relations in all three plant groups simultaneously, to test the hypothesis on the evolutionary process of plant hydraulics. Methods We selected three species in each group grown in South China Botanical Garden, Guangzhou, China, including ferns (Dicranopteris pedata, Cyclosorus parasiticus and Blechnum orientale), gymnosperms (Podocarpus macrophyllus, Podocarpus nagi and Taxodium distichum) and angiosperms (Manglietia fordiana var. hainanensis, Sindora tonkinensis and Bauhinia purpurea). Important findings Sapwood and leaf specific hydraulic conductivities (KS and KL, respectively), and leaf conductance (Kleaf) significantly increased from ferns, gymnosperms to angiosperms. However, no significant trends were found in transpiration rate (E) and intrinsic water use efficiency. Meanwhile, neither the size and density of stomata nor wood density showed significant difference among three plant groups. The hydraulic functional traits (KS, KL and Kleaf) had significantly positive correlations with each other, but had no relationships with the two measured structural traits. Phylogenetic independent contrasts analyses showed that the coordination between KS and Kleaf, and between KS and E were independent of the phylogeny. Based on the nine vascular species, this study demonstrated that water transport related traits are improved as vascular plants evolved, and the co-evolution between water transport and transpiration traits were identified. For further study, it is necessary to consolidate our data with investigations of more detailed water-transport structures in more species from different evolutionary lineages. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.     

八属木兰科植物木材导管分子的比较解剖

本文比较描述了我国木兰科木莲属、华盖木属,长蕊木兰属,拟单性木兰属,合果木属,观光木属,香木兰属和鹅掌楸属等8属22种植物次生质部的导管分子,这些导管分子的长度和宽度都有差异,木莲属的所有种中都有具梯状穿孔板的导管分子,但在少数种中偶然可见到单穿孔,在其它属中,也都有具梯状穿孔板的导管分子,仅在观光木属中偶见的单穿孔,木莲属大多数种均无螺纹加厚,仅桂南木莲一种除外,另外,除了合果木属和鹅掌楸无螺纹加厚外,其余均有此种加厚,各属的导管分子还存在其它一些差异。     

中国亚热带常绿阔叶林优势种及常见种的水热分布类群

 利用目前国际上比较常用的植被—气候相关分析的气候指标,如Kira的温暖指数和寒冷指数,徐文铎的湿润指数,Penman的可能蒸散和干燥度指标,Thornthwaite的潜在可能蒸散和水分指数,Holdridge生命地带分类系统指标以及气温和降水等单一气候因子,综合对中国亚热带常绿阔叶林优势种及常见种进行TWINSPAN分类和DCA排序,可将植物种分为8个水热分布类群,较好地反映出优势种及常见种沿热量和水分梯度的分布格局。并总结了这8个水热分布类群的气候指标范围。这8个类群是：Ⅰ高温湿润型,Ⅱ高中温湿润型,Ⅲ低中温湿润型,Ⅳ高低温中湿型,Ⅴ低低温中湿型,Ⅵ低温半湿润型,Ⅶ高低温低湿型,Ⅷ低低温低湿型     

Manglietia lawii sp. nov. (Magnoliaceae) from Yunnan, China

Manglietia lawii N. H. Xia & W. F. Liao, a new species of Manglietia from Yunnan, China, is described and illustrated. It is closely related to M. forrestii W. W. Smith, but differs by having villous gynoecium and glabrous tepals.