中国西南与台湾地区维管植物的间断分布格局及形成机制

植物的间断分布格局及其形成机制是植物地理学研究的重要问题之一。本文在对中国大陆与台湾名录整理比较的基础上,对中国西南与台湾地区的植物间断分布格局及形成机制进行了分析。结果表明,两地同种型间断分布的维管植物有198种(包括变种和亚种),隶属于56科129属,其中蕨类植物86种,裸子植物3种,双子叶植物56种,单子叶植物53种;两地异种型间断分布的维管植物有22属,隶属于15科,其中蕨类植物6属,裸子植物1属,双子叶植物7属,单子叶植物兰科8属。间断分布类群以草本植物为主,主要是蕨类和兰科植物。间断分布类群在台湾地区主要分布在中部到东北部,在大陆的分布主要集中在川东–鄂西地区、川西–滇西北地区–藏东南地区和滇东南–桂西–黔西南地区。在垂直高度上,海拔1,550–2,350m是间断分布类群最集中分布的海拔范围。我们推测中国西南与台湾地区的间断分布类群有3种来源:北半球温带、中国西南和热带亚洲来源。     

中国种子植物属的地理成分分布格局及其与气候和地理的关系

基于覆盖了全中国各地理区的204个地区植物区系研究资料和这些地区的841个气象站资料,我们对中国种子植物属的地理成分分布格局及其与气候、经纬度分布的关系进行了研究,并结合这些分布格局探讨了中国植被分带和植物区系分区。结果如下：（1）除世界分布、栽培和入侵成分外,大部分中国种子植物属的地理成分的分布与地理相关密切;（2）热带分布属（泛热带分布、热带亚洲至热带美洲间断分布、旧世界热带分布、热带亚洲至热带大洋洲分布、热带亚洲至热带非洲分布及热带亚洲分布合计）占各地方植物区系的0．84％到94．38％,其最低值出现在中国西北部的新疆和青海地区,最高值出现在中国云南南部和海南;（3）热带分布属在〈北纬30°的地区占优势,除热带亚洲至热带美洲间断分布外,其它热带成分随纬度增加迅速减少;（4）温带分布属（北温带分布、东亚和北美间断分布、旧世界温带分布、温带亚洲分布、地中海区、西亚到中亚分布、中亚分布和东亚分布合计）占各地方植物区系的5．1％至98．83％,其最高值出现在中国西北部的新疆地区,最低值出现在中国云南南部和海南;（5）除东亚和北美间断分布、东亚分布和中国特有分布外,其它温带成分随纬度增加迅速增加;（6）在温带成分中,东亚和北美间断分布及东亚分布属主要出现在中国亚热带到暖温带地区,北温带分布、旧世界温带分布和温带亚洲分布属在中国北部占优势,而地中海区、西亚到中亚分布和中亚分布属则在中国西北部占优势;（7）除世界分布、东亚和北美间断分布、东亚分布和中国特有分布外,所有其他成分都显示了与气候因素（主要是气温和降雨量）密切相关,其中,北温带分布属与年均温和年降雨量最为密切相关。中国种子植物属的地理成分的分布格局与现行的中国植被分带和植物区系分区密切匹配。支持现行的中国植被分带和植物区系分区方案。     

蜡梅科植物的起源演化及其分布

根据对蜡梅科植物的系统发育和分布规律的研究,结合古地理、古气候资料,讨论了蜡梅科的起源、演化和现代分布格局形成的规律。认为：中国泰岭以南、横断山脉以东为蜡梅科植物的现代分布中心。蜡梅科植物的起源地点可能在东亚,并在第四纪时通过白令陆桥到达北美;通过中南半岛、马来半岛到澳洲,并在各个洲独立发展,形成现在的东亚－北美间断分布及南北温带间断分布的格局。     

中国松科植物的分布型和区系分析

简介松科研究的新进展,根据新近资料划分中国松科植物10属95种的分布型和进行区系分析,结果是北温带分布4属,东亚-北美间断分布2属,中国特有3属和越南-华南分布1属。25个种分布型分属于欧亚温带、东亚和亚洲热带3个植物区域。比较详细分析其4点主要特征;分布的区域差异和不平衡,高的特有性,间断分布和替代分布等。     

中国壳斗科植物属的分布区定量研究

通过植物专业网站及发表的论文论著,收集每一种壳斗科植物在中国的具体分布地点（县）,并采用地理信息系统技术,以县为空间数据的基本单元,以壳斗科植物为研究对象,制作属的空间分布图,从图中定量地提取斑块的数目、面积、周长,计算形状指数、最大斑块指数,以及属的Shannon均匀度指数、Simpson均匀度指数,分析中国壳斗科植物属的空间分布及其特点,为植物区系空间分布定量研究提供依据。结果表明：（1）中国壳斗科植物属的空间分布呈现连续分布或间断分布,间断分布有星散分布、主次分布区、主分布区3种类型,以图形和定量的方式体现出属在空间上的分布差异。（2）中国壳斗科植物属的分布区或最大斑块的分布区在中国亚热带,能连续分布到热带,但在温带斑块分散,面积小,由此推断中国亚热带植物区系应划分为古热带植物区。（3）根据三棱栎属、锥属、柯属在世界和中国的分布,推断它们均为热带亚洲和热带美洲洲际间断分布。     

中国松科植物的分布型和区系分析

简介松科研究的新进展,根据新近资料划分中国松科植物１０属９５种的分布型和进行区系分析,结果是北温带分布４属,东亚－北美间断分布２属,中国特有３属和越南－华南分布１属。２５个种分布型分属于欧亚温带、东亚和亚热带３仆植物区域。比较详细分析其４点主要特征：分布的区域差异和不平衡,高的特有性,间断分布和替代分布等。     

中国西南地区与台湾种子植物间断分布现象

中国西南地区和台湾植物的间断分布是东亚生物地理学上一个十分有趣的研究课题。该文对种子植物进行了统计,发现有50属具有该分布式样的种对或种（包括变种和亚种）;30属呈台-琼（至粤南）-西南间断分布,而其中大多数类群的分布区在粤南-桂南-滇南,即中国热带线以南。统计结果显示,有41属被子植物在台湾和西南之间呈连续分布;有35属从台湾分布至海南（和/或华南）或至福建（和华南）。中国台湾和大陆之间类群的连续分布,以及两者植物区系的巨大相似性表明,台湾作为大陆性岛屿,与中国大陆曾经属于一个统一的植物区系。新近纪以来台湾中央山脉和中国西南至东喜马拉雅地区均经历了海拔升高的过程,形成相似的低至中、高山生境;在第四纪冰期,一些类群在这两个地区之间形成连续的分布区。后来全球气温升高,这些植物类群从低海拔向高海拔山区迁移,由于华东至华中和华南缺少高山生境,使得原来连续分布的某些类群或其祖先类群在中国西南和台湾两地之间灭绝,从而形成间断分布。同时,台湾与大陆失去陆地连接后造成分类群在台湾和西南地区的隔离分化,以及中国南端热带生境的不连续性导致热带植物属种分布区的破碎也是形成台湾和西南间断分布的重要因素。最后将西南和台湾间断分布类群归纳为3种类型：孑遗型、分化型和热带型。     

中国高山萤叶甲区系研究

讨论的高山萤叶甲系指分布在海拔２５００ｍ以上的中国种类,总计１３１种,分隶于４９属,分别占萤叶甲亚科我国已知种,属的１／６和１／２,其分布区域以青藏高原,特别是横断山区种,属分布最为密集。部分属,种也涉及到台湾,而且表现出台湾与中国西部横断山区间断分布现象。     

黄杉属植物在云南的资源现状及保护利用研究

黄杉属(PseudotsugaCarr.)是东亚和北美间断分布的重要类群,在我国分布有5种,它们都是受国家二级保护的中国特有种类。对黄杉(PseudotsugasinensisDode)和澜沧黄杉(PseudotsugaforrestiiCraib)在云南分布资源状况进行调查研究,揭示了其种群现状、自然更新能力、当地居民的利用及导致树种濒危的可能因素,指出实现云南黄杉属种质资源有效保护和开发利用所面对的问题及应采取的措施。     

几种石耳科地衣生物地理学关系的分子评估(英文)

对具有北美东部和亚洲东部近缘生物地理学关系的大型地衣种类进行系统发育检测较少。笔者获得了石耳科中8个种10个样本nrDNA的ITS完整序列,并对本科中在分布上具有重要意义的4个种的生物地理学关系进行了分析和评估。通过对细胞核核糖体DNA变异性较强的ITS段碱基序列的比较分析,支持放射盘石耳(Umbilicaria muehlenbergii)、宾州疱脐衣(Lasallia pennsylvanica)为同种型间断分布,美味石耳(U.escu-lenta)和大叶石耳(U.mammulata)间已经达到了相当高的分化程度,为异种型间断分布。地理学分析显示该两种石耳的分化可能是由于太平洋的扩展和隔离所造成的结果。同种型间断分布种类的不同地区的样本之间的差异较小。推测了不同类型间断分布种类的分化时间,美味石耳与大叶石耳的分化发生在中新世(23～5.33 Mya)中期,白令海峡形成期间。     

Actaea muliensis sp. nov. (Ranunculaceae), an unusual species with dark purple staminodes from western Sichuan,China

Actaea muliensis (Ranunculaceae), a new species from Muli County, Sichuan Province, China, is described and illustrated. Morphologically, it is somewhat similar to A. mairei, but is most readily distinguishable from that species and others within A. sect. Cimicifuga by, among other characters, the dark purple (vs yellow) staminodes. Actaea muliensis is revealed to be a diploid (2n = 16) species with 3‐colpate pollen.     

Maintenance of species boundaries in a Neotropical radiation of Begonia

A major goal of evolutionary biology is to determine the mechanisms generating biodiversity. In Begonia, one of the largest plant genera (1900+ species), it has been postulated that the high number of endemic species is a by‐product of low gene flow among populations, which predisposes the group to speciation. However, this model of divergence requires that reproductive barriers accumulate rapidly among diverging species that overlap in their geographic ranges, otherwise speciation will be opposed by homogenizing gene flow in zones of secondary contact. Here, we test the outcomes of secondary contact in Begonia by genotyping multiple sympatric sites with 12 nuclear and seven plastid loci. We show that three sites of secondary contact between B. heracleifolia and B. nelumbiifolia are highly structured, mostly containing parental genotypes, with few F1 hybrids. A sympatric site between B. heracleifolia and B. sericoneura contains a higher proportion of F1s, but little evidence of introgression. The lack of later‐generation hybrids contrasts with that documented in many other plant taxa, where introgression is extensive. Our results, in conjunction with previous genetic work, show that Begonia demonstrate properties making them exceptionally prone to speciation, at multiple stages along the divergence continuum. Not only are populations weakly connected by gene flow, promoting allopatric speciation, but species often show strong reproductive barriers in secondary contact. Whether similar mechanisms contribute to diversification in other large genera remains to be tested.     

大叶铁线莲访花昆虫调查及盗蜜昆虫行为研究

大叶铁线莲Clematis heracleifolia DC. 的花朵大多下垂,需要传粉昆虫为其传粉,目前尚无关于其访花昆虫研究的报道。 通过2年的野外观察研究,共观察到27种昆虫访问大叶铁线莲。 发现有盗蜜行为的昆虫7种, 其中1种同时具有初级盗蜜和次级盗蜜行为,2种具有初级盗蜜行为,4种具有次级盗蜜行为;黄胸木蜂Xylocopa appendiculata Smith是主要的盗蜜昆虫,其盗蜜行为影响了其它昆虫的访花行为,对大叶铁线莲的传粉造成一定的影响。 在其余20种访花昆虫中,双带弄蝶Lobocla bifasciata (Bremer et Grey)、贡尺蛾Gonodontis aurata Prout、熊蜂Bombus sp.和姬蜂虻Systropus sp.是优势种; 而小青花金龟Oxycetonia jucunda Faldermann和日本条螽Ducetia japonica (Thunberg)访花频率最低,且访花目的只是取食花朵。 通过对大叶铁线莲访花昆虫的调查和盗蜜昆虫行为的研究,为大叶铁线莲的传粉生物学和保护提供参考依据。     

Meristem activity and biomass production as response mechanisms in two forest herbs

Actaea spicata and Geranium sylvaticum are deciduous rosette herbs, frequently coexisting in nutrient-rich forests of boreal Sweden. A. spicata is restricted to this habitat whereas G. sylvaticum has a wider ecological amplitude. To explore the different distributions of these species we studied the growth mechanisms by which they responded to nutrient and light supply. Plants raised from seeds were grown under four combinations of light and nutrient supplies and growth was followed for 20 weeks. Growth responses were measured as biomass accumulation and meristem activity, i.e. leaf development by shoot meristems. Biomass accumulation and meristem activity were affected by nutrient and light treatments. However, A. spicata responded more to nutrients, whereas G. sylvaticum responded more to light, and low resource supply shortened the time during which shoot meristems of A. spicata developed leaves without a corresponding effect on biomass accumulation. In G. sylvaticum, the periods of leaf development and biomass accumulation were the same, but a relationship between high development rates and peak allocation of biomass to shoot meristems indicated a storage function of these during leaf development. We conclude that the inflexible growth of A. spicata, mainly affected by nutrient supply, makes it less competitive in open habitats and restricts it to shaded, nutrient-rich habitats. G. sylvaticum should be more successful in habitats subjected to unpredictable disturbances, due to a flexible growth morphology and a dynamic function of meristems that buffers against variation in nutrient supply and facilitates positive light responses. Meristematic data should be included in interspecific comparisons on growth responses to different resource supplies. Unless species have the same growth mechanism, it is not satisfactory to study biomass-related traits alone, as internal constraints concerning plant development might confuse the interpretation.     

Genetic differentiation and species cohesion in two widespread Central American Begonia species

Begonia is one of the ten largest plant genera, with over 1500 species. This high species richness may in part be explained by weak species cohesion, which has allowed speciation by divergence in allopatry. In this study, we investigate species cohesion in the widespread Central American Begonia heracleifolia and Begonia nelumbiifolia, by genotyping populations at microsatellite loci. We then test for post-zygotic reproductive barriers using experimental crosses, and assess whether sterility barriers are related to intraspecific changes in genome size, indicating major genome restructuring between isolated populations. Strong population substructure was found for B. heracleifolia (F_ST=0.364, F′_ST=0.506) and B. nelumbiifolia (F_ST=0.277, F′_ST=0.439), and Bayesian admixture analysis supports the division of most populations into discrete genetic clusters. Moderate levels of inferred selfing (B. heracleifolia s=0.40, B. nelumbiifolia s=0.62) and dispersal limitation are likely to have contributed to significant genetic differentiation (B. heracleifolia Jost''s D=0.274; B. nelumbiifolia D=0.294). Interpopulation crosses involving a divergent B. heracleifolia population with a genome size ∼10% larger than the species mean had a ∼20% reduction in pollen viability compared with other outcrosses, supporting reproductive isolation being polymorphic within the species. The population genetic data suggest that Begonia populations are only weakly connected by gene flow, allowing reproductive barriers to accumulate between the most isolated populations. This supports allopatric divergence in situ being the precursor of speciation in Begonia, and may also be a common speciation mechanism in other tropical herbaceous plant groups.     

KARYOTYPES OF FIVE PLANT SPECIES WITH DISJUNCT DISTRIBUTIONS IN VIRGINIA AND THE CAROLINAS

Five species (Actaea pachypoda, Aralia nudicaulis, Cornus alternifolia, Panax quinquefolius, and Symplocarpus foetidus) display a disjunct distribution between the Mountains and Piedmont in North Carolina, South Carolina, and Virginia. The Piedmont populations are small and have apparently been isolated from the Mountain populations for several thousand years. Karyotype differences among populations were found only in A. pachypoda, and even in this species the differences were slight. The absence of population differences in four species, and the moderate differentiation found in A. pachypoda, indicate considerable cytological stability in these species.     

Recruitment and growth in Aconitum septentrionale and Actaea spicata in relation to microbial soil communities manipulated by additions of glucose and nutrients

Sowing experiments were used to study seedling recruitment, growth and biomass allocation patterns in the perennial forest herbs Aconitum septentrionale and Actaea spicata in relation to the microbial soil community. Glucose and nutrients were added every second week over a 3-year period to manipulate soil microbial activity and nutrient availability. The glucose was added (400 g glucose m⁻² yr⁻¹) to reduce the nutrient availability to the plants by increasing soil microbial demands. A full nutrient solution was used to increase the nutrient availability. The experiments were performed in a deciduous forest and in an open field in South East Norway, and our study is based on a consecutive sampling of whole plants with intact root systems to be able to estimate growth and allocation patterns. Both species recruited best in the forest while their growth in the open field was ca. 100 times larger than in the forest. Shoot:root ratios were surprisingly similar in the forest and the open field sites and were only marginally affected by the glucose and nutrient treatments. However, the shoot:root ratios were characterised by highly significant seasonal variations. This was the case for both species and indicates that the shoot:root ratios were under strong ontogenetic control. Recruitment was negatively affected by glucose additions, in particular in the open field. Growth was significantly and negatively affected by glucose additions in the forest. Nutrient additions gave, as expected, a significant increase in growth. The failure of seedling recruitment and inferior growth following glucose additions support the assumption that the soil microbial community is an important determinant of plant recruitment and growth.     

云南被子植物新资料

植物资源调查是探讨系统发育、植物区系进化历史和亲缘关系的基础,是我国植物研究工作的重要任务之一,虽然我国在植物资源调查方面有了丰富的积累,并以《中国植物志》和各地方植物志为代表,但部分偏远地区的植物资源状况仍然缺乏数据。该研究通过形态特征比较分析,发现云南省被子植物新记录3种,即柳叶黄肉楠(Actinodaphne lecomtei C. K. Allen)原分布于四川、贵州、广东(乳源)、广西,云南省丘北县为其新记录点;八角樟(Cinnamomum ilicioides A. Chevalier)原分布于中国的广东、海南、广西和越南北部,云南省西双版纳傣族自治州勐腊县为其新记录点;贵州山核桃(Carya kweichowensis Kuang A. M. Lu ex Chang et Lu)原分布于贵州安龙、望谟、册亨、兴义等,云南省丘北县为其新记录点。柳叶黄肉楠和八角樟在云南的新分布点是对我国樟科薄弱地带的补充,为分析滇产原始种类对相关属的起源发生和中国樟科分类学研究提供了新材料;贵州山核桃在物种层面上对确定贵州山核桃与喙核桃(Annamocarya sinensis)两者之间的联系提供了新的案例,并为云南发展山核桃(Carya cathayensis)生产提供了种质资源。     

华南吊灯花属(夹竹桃科)植物小志

通过野外调查、标本查阅及文献考证,订正了华南吊灯花属(Ceropegia Linn.)植物,将狭瓣吊灯花(C. angustilimba Merr.)从吊灯花(C. trichantha Hemsl.)的异名中予以恢复,提供了二者的形态描述,确认华南地区记录的柳叶吊灯花(C. salicifolia H. Huber)实为剑叶吊灯花(C. dolichophylla Schltr.)的错误鉴定,并提供了后者的形态描述。     

中国黑粉补遗

裂孢黑粉菌属(Schizonella)是我国新记录属,其主要特征为孢子堆生叶上;黑粉成对,其萌发方式同黑粉菌属(Ustilago)苔草裂孢黑粉菌(Schizonella melanogramma(DC.) Schrot.)寄生于苔草属(Carex sp.)植物上,其孢子堆生叶上,条状,粉质;黑粉孢子卵形,近球形或不规则半球形,常成对,7.5 -12.5 (-14)×5.5-(-12)µm,橄榄褐色.另一我国新记录种是鬼灯檠条黑粉菌(Urocystis rodgersiae (Miyabe) Miyabe ex Zund.),寄生在鬼灯檠(Rodgersia aesculifolia Batal.)植物上.孢子堆生叶下;孢子球27-60(-75)×25-45.5(-57µm,由1-6个黑粉孢子组成;不育细胞10-15×9-l0µm,浅褐色.黑粉孢子14-20×10-14µm,暗褐色.此种孢子球比原产于日本的模式种略大,其它特征相同.