云南的硬叶常绿阔叶林——古地中海残余植被

云南从干热河谷到寒温性山地广泛分布有一类常绿、阔叶、以壳斗科栎属植物为乔木优势种的森林植被，由于其独特的生态特征显示了与现代地中海地区硬叶栎林的相似性，而在群落的外貌、结构、特征种、地理分布等方面却与云南的亚热带常绿阔叶林有明显区别，因此被称为“硬叶常绿阔叶林”,它是在喜马拉雅隆升中因适应新的环境而发育的一个特殊植被类型。该植被的优势树种具有古地中海地区渊源，但在分布上大多为我国西南地区的特有种。硬叶常绿阔叶林除优势树种为硬叶栎类以外，其他种类与同域天然植被的物种组成基本一样，并没有一个独特的植物区系。硬叶常绿阔叶林群落结构简单，典型的硬叶常绿阔叶林群落有清楚的乔木、灌木和草本3个层次，而在生活型上，寒温性山地的群落以地面芽植物占绝对优势，干热河谷的群落以草本植物占优势。在中新世以前，硬叶栎类植物出现在湿润的热带-亚热带性质的古地中海常绿阔叶林里，直到上新世以后，现代的地中海式气候形成，适应干旱的地中海植物区系出现，并随喜马拉雅隆升，硬叶常绿阔叶林才从原先的热带-亚热带常绿阔叶林演化产生。     

宁波北仑常绿阔叶林植被性质研究

本文对常绿阔叶林的区系组成,生活型谱,叶的性质以及群落结构等进行研究,结果表明：组成植被的热带属略占优势,区系组成极为分散,常绿建群种大多在Ｃａｓｔａｎｏｐｓｉｓ,Ｃｙｃｌｏｂａｌａｎｏｐｓｉｓ二个属中,植被性质主要表现为中亚絷带常绿阔叶林特征,并逐渐向北亚热带过渡,优势种群的结构表明,本区植被已接近常绿阔叶林演替的顶极阶段。     

云南常绿阔叶林的植被地理研究

云南具有极其丰富的生物多样性和以常绿阔叶林为优势的植被类型。该研究利用6个基于样方层面的1 hm²样地资料, 以及通过对整个植被类型的植物区系的调查, 对云南常绿阔叶林植被型的3个植被亚型(季风常绿阔叶林、半湿润常绿阔叶林和中山湿性常绿阔叶林)的生态外貌特征、植物区系组成及其生物地理演化进行了研究。在样方层面, 尽管这3个常绿阔叶林在树种组成上优势种均为壳斗科、樟科和山茶科植物, 但它们在种类组成、多样性、生态外貌和生物地理特征上呈现多样化。分布在南部及西南部的季风常绿阔叶林物种组成极其丰富, 具有热带森林的生态外貌, 并以热带亚洲分布种为优势种。主要分布在云南高原的半湿润常绿阔叶林和云南中部和北部山地的中山湿性常绿阔叶林具有亚热带常绿阔叶林的生态外貌特征和以中国-喜马拉雅及中国特有种占优势, 是中国西南独特的植被类型。在植被亚型层面, 这3个常绿阔叶林的植物区系(包括所有生活型的种子植物)中种数最多的科, 按地理成分均为世界分布型的科, 含种数较少的科则为其他各种分布型的科。半湿润常绿阔叶林和中山湿性常绿阔叶林的植物区系, 热带分布属分别占总属数的44.91%和44.04%, 温带分布属占46.29%和48.19%, 其中北温带分布属比例最高, 分别为18.36%和19.95%。季风常绿阔叶林植物区系则显示了不同的地理成分格局: 热带分布属占总属数的78.05%, 并以热带亚洲分布属占最高比例。通过对这3个常绿阔叶林的比较发现, 半湿润常绿阔叶林和中山湿性常绿阔叶林除生态外貌特征有一定区别外, 在植物区系组成和地理成分上很接近, 它们在种的组成上, 与季风常绿阔叶林的类似性仅为17.1%和15.4%。季风常绿阔叶林因其在植物区系和生态外貌上与后二者区别明显, 建议在云南植被分类上划分一个独立的植被型, 它是东南亚低山常绿阔叶林分布在中国西南部热带北缘山地的一个植被类型。结合云南的地质历史和古植物学资料, 认为云南的常绿阔叶林及其植物区系受晚中新世以来的地质历史事件深刻影响。半湿润常绿阔叶林是中国西南独特而特有种丰富的植被类型, 由于严重的人为干扰破坏, 现已片段化或成为萌生灌丛状, 应给予优先保护。     

青藏高原晚新生代植被史及其气候特征

从青藏高原目前已知的６０余个剖面和钻孔揭示的大量古植物资料来看,由于喜马拉雅山的强烈隆升、地质事件及全球气候变化,青藏高原晚新生代植被发生显著的变化。中新世进入上新世,植被由森林型变为草原型。在中新世晚期植被按纬向分为三带,南带为亚热带硬叶常绿阔叶林－雪松林,中带为暖温带落叶阔叶林及灌丛,北带即昆仑山北坡为山地常绿针叶林及森林草原。山地的高差已使植被出现垂直分带现象。上新世早中期气候转凉,原北带出     

云南热带森林植被分类纲要

热带森林是云南的重要植被类型,虽对云南热带森林植被的系统分类及研究在《云南植被》中有所体现,并发表了大量论文,但在植被类型的划分、命名及其解释上却不尽相同,特别是对群系的记录很不全面。该文总结已掌握的研究资料,参考世界类似热带森林植被的研究成果,系统地对云南热带森林植被的类型、分类、物种组成和群落特征等进行了归纳。结果表明:云南的热带森林植被包括3个主要的植被型,即热带雨林、季雨林、季节性湿润林。云南的热带雨林是在亚洲热带北缘季风气候下发育的在水分、热量和分布海拔上均到了极限条件的热带雨林类型,分为热带季节性雨林和其山地变型—热带山地雨林二个植被亚型,前者包括19个群系,后者包括12个群系。文中的热带季雨林是依据其原始定义指介于热带雨林与萨王纳之间的一种热带落叶至半常绿森林植被,其分布主要受水分条件制约,非纬向地带性植被;它们分为落叶季雨林和半常绿季雨林2个植被亚型,前者包括7个群系,后者包括3个群系。把分布于云南南部石灰岩山地的在一些植物学文献中称之为"石灰岩季雨林"的热带森林植被,考虑其常绿至半常绿的外貌特征、特殊的植物区系组成以及乔木层没有一个明显的无叶(落叶)期(其落叶现象可能主要由于局部生境的干燥和历史的原因,并非是由于地区性气候干旱所导致),它们与季雨林的原始定义不符;该文使用名称热带季节性湿润林来定义这类发生在石灰岩山中、上部,在热带季节雨林带之上的热带山地垂直带上的植被类型。季节性湿润林也分为季节性常绿湿润林及季节性半常绿湿润林2个植被亚型,各包括2个群系。     

内伶仃岛主要植被及群落类型的特征和分布

广东省内伶仃岛位于珠江口伶仃洋的东部,属南亚热带季风气候区,其自然植被的主要类型有：南亚热带常绿针叶林、南亚热带针阔叶混交林、南亚热带常绿阔叶林、南亚热带红树林、南亚热带竹林、南亚热带常绿灌丛、南亚热带灌草丛、滨海砂生灌草丛等,包括８个植被亚型、１８个群系。人工植被主要有台湾相思林等４个群系,以及果园林４类、作物园４类。地带性植被为南亚热带常绿阔叶林;优势植被类型为台湾相思林、马尾松林,两者的建群种均为衰退种群,已形成多个发育阶段。论文对各主要植被类型及群落结构特征进行分析。     

广西金钟山自然保护区主要植被类型的特征

金钟山自然保护区计有种子植物101科273属514种,落叶栎林分布面积最广。随海拔升高,植被依次呈现出4个分布带:沟谷落叶阔叶林、沟谷常绿阔叶林、常绿落叶阔叶混交林和落叶阔叶林、山地苔藓矮林和山地常绿阔叶林。该区主要有4个分布区类型:世界分布、热带分布、温带分布和中国特有分布,其中热带分布占总属数的75.21%,表明本保护区的植物分布具有热带性质。其天然植被类型可划分为5个植被型组,7个植被型含暖性针叶林、暖性落叶阔叶林、常绿落叶阔叶混交林、常绿阔叶林、竹林和草丛,2个植被亚型含南亚热带山地常绿阔叶林、山顶阔叶矮林,以及33个群系。     

深圳市植被的基本特点及其生态评价

深圳市是我国沿海对外开放的经济特区,位于广东省的南部,与香港相连,面临热带南海,为热带、亚热带的过渡区。本市植被类型多样,地带性的代表植被类型为热带常绿季雨林和南亚热带季雨性常绿阔叶林;其组成种类、外貌和结构以及群落的组合和分布规律均表现出热带和亚热带的过渡性,显示出与环境相适应的关系。根据本市植被类型的组合、分布及其与环境的关系,从植物生态学的角度提出植被的生态评价,为经济特区农、林、果、牧等的合理开发利用和改造提供科学依据。     

珠江口内伶仃岛植被

内伶仃岛现状植被主要是:南亚热带常绿阔叶林,南亚热带针叶林,红树林,南亚热带灌丛,南亚热带山坡草地,滨海砂生灌草丛,人工林。文内还阐述了猕猴生态环境和植物资源。     

江苏省地带性植被的基本特点与分布规律

江苏省地跨南暖温带、北亚热带和中亚热带三个生物气候带,典型地带性植被类型依次为落叶阔叶林、落叶常绿阔叶混交林和常绿阔叶林。前两个类型也分别见于北亚热带和中亚热带地区。三个地带性植被类型的主要类型及其分布与组成特点,分别列表概述。落叶常绿阔叶混交林是落叶林与常绿阔叶林之间的过渡类型,在北亚热带地区,林内落叶树的种类与数量往往超过常绿树,落叶层片占优势地位。江苏境内的常绿阔叶林,因地处中亚热带北缘,具有一定的过渡性特征,林内落叶阔叶树的种类往往超过常绿阔叶树,但后者的多度与盖度均占显著优势地位,常绿层片为主,所以外貌为常绿阔叶林。 江苏没有高山,东西间狭窄,故植被的垂直地带性和经度地带性分布规律均未显示。但南北间宽广,跨纬度4?以上,从北向南气候梯度变化明显,所以植被分布的纬度地带性规律明显。     

The Early Pliocene re-colonisation of the deep Mediterranean Sea by benthic foraminifera and their pulsed Late Pliocene–Middle Pleistocene decline

Ninety-five species and 19 genera of cosmopolitan, deep-sea benthic foraminifera belonging to the families Pleurostomellidae, Stilostomellidae and Nodosariidae, became extinct during the Late Pliocene–Middle Pleistocene. Only 50% of these (44 species) were present in the Pliocene or Pleistocene of the deep Mediterranean Sea (ODP Sites 654, 966, 967, 975, 976), being those which had successfully migrated in via the Strait of Gibraltar from the deep Atlantic following the annihilation of the Mediterranean deep-sea fauna during the Late Miocene Messinian Crisis. Most colonisation occurred within the first 0.8 myrs (5.3–4.5 Ma) after re-establishment of the Mediterranean–Atlantic link, with possibly a second lesser period of immigration in the Late Pliocene (3.4–3.0 Ma). We infer that colonisations may have been fortuitous and few in number, as some common members of the group in the Atlantic never succeeded in establishing in the Mediterranean Sea. There is no evidence of any new immigration events during the Pleistocene, implying that the present anti-estuarine circulation may have been in place throughout this period. Our studies suggest that these deep-water, low-oxygen-tolerant foraminifera survived the many periods of deep-water sapropel formation in the Pliocene–Early Pleistocene, possibly in somewhat shallower (~ 500 m) refuges with dysoxic, rather than anoxic conditions.The Pliocene–Pleistocene stratigraphic record of this group of elongate, cylindrical benthic foraminifera with constricted and specialised apertures is similar in the west and east Mediterranean basins. The group declined in abundance (flux) and diversity in two pulses, during the Late Pliocene (3.1–2.7 Ma) and the late Early Pleistocene (1.3–1.0 Ma) in concert with global, southern-sourced, deep-water sites (AABW, CPDW) and earlier than the single decline (1.0–0.6 Ma) in global, intermediate water sites (uNADW, AAIW). All species, with one possible exception, disappeared earlier in the Mediterranean than globally. The highest occurrence of any species of this group in Mediterranean sites was 0.8–0.43 Ma, comparable with 0.7–0.2 Ma outside with the youngest survivors being in abyssal, deep-water.Thus, despite the unusual oceanographic conditions and isolation, the deep Mediterranean Sea was in this case neither the centre for the evolution of new species nor a refuge where species survived after they had disappeared elsewhere.     

Climate‐driven rampant speciation of the Cape flora

Aim To test whether the radiation of the extremely rich Cape flora is correlated with marine‐driven climate change. Location Middle to Late Miocene in the south‐east Atlantic and the Benguela Upwelling System (BUS) off the west coast of South Africa. Methods We studied the palynology of the thoroughly dated Middle to Late Miocene sediments of Ocean Drilling Program (ODP) Site 1085 retrieved from the Atlantic off the mouth of the Orange River. Both marine upwelling and terrestrial input are recorded at this site, which allows a direct correlation between changes in the terrestrial flora and the marine BUS in the south‐east Atlantic. Results Pollen types from plants of tropical affinity disappeared, and those from the Cape flora gradually increased, between 10 and 6 Ma. Our data corroborate the inferred dating of the diversification in Aizoaceae c. 8 Ma. Main conclusions Inferred vegetation changes for the Late Miocene south‐western African coast are the disappearance of Podocarpus‐dominated Afromontane forests, and a change in the vegetation of the coastal plain from tropical grassland and thicket to semi‐arid succulent vegetation. These changes are indicative of an increased summer drought, and are in step with the development of the southern BUS. They pre‐date the Pliocene uplift of the East African escarpment, suggesting that this did not play a role in stimulating vegetation change. Some Fynbos elements were present throughout the recorded period (from 11 Ma), suggesting that at least some elements of this vegetation were already in place during the onset of the BUS. This is consistent with a marine‐driven climate change in south‐western Africa triggering substantial radiation in the terrestrial flora, especially in the Aizoaceae.     

Miocene to Pliocene vegetation reconstruction and climate estimates in the Iberian Peninsula from pollen data

Pollen analysis of Miocene and Pliocene sediments from the Iberian Peninsula shows a progressive reduction in plant diversity through time caused by the disappearance of thermophilous and high-water requirement plants. In addition, an increase in warm-temperate (mesothermic), seasonal-adapted “Mediterranean” taxa, high-elevation conifers and herbs (mainly Artemisia) occurred during the Middle and Late Miocene and Pliocene. This has mainly been interpreted as a response of the vegetation to global and regional processes, including climate cooling related to the development of the East Antarctic Ice Sheet and then the onset of the Arctic Ice Sheet, uplift of regional mountains related to the Alpine uplift and the progressive movement of Eurasia towards northern latitudes as a result of the northwards subduction of Africa. The development of steppe-like vegetation in southern Iberia is ancient and probably started during the Oligocene. The onset of a contrasted seasonality in temperature during the Mid-Pliocene superimposed on the pre-existing seasonality in precipitation, the annual length of which increased southward. The Mediterranean climatic rhythm (summer drought) began about 3.4 Ma and caused the individualization of modern Mediterranean ecosystems. Quaternary-type Mediterranean climatic fluctuations started at 2.6 Ma (Gelasian) resulting in repeated steppe vs. forest alternations. A latitudinal climatic gradient between the southern and the northern parts of the Iberian Peninsula existed since the Middle Miocene.     

Pliocene–Pleistocene ecological niche evolution shapes the phylogeography of a Mediterranean plant group

Estimating species ability to adapt to environmental changes is crucial to understand their past and future response to climate change. The Mediterranean Basin has experienced remarkable climatic changes since the Miocene, which have greatly influenced the evolution of the Mediterranean flora. Here, we examine the evolutionary history and biogeographic patterns of two sedge sister species (Carex, Cyperaceae) restricted to the western Mediterranean Basin, but with Pliocene fossil record in central Europe. In particular, we estimated the evolution of climatic niches through time and its influence in lineage differentiation. We carried out a dated phylogenetic–phylogeographic study based on seven DNA regions (nDNA and ptDNA) and fingerprinting data (AFLPs), and modelled ecological niches and species distributions for the Pliocene, Pleistocene and present. Phylogenetic and divergence time analyses revealed that both species form a monophyletic lineage originated in the late Pliocene–early Pleistocene. We detected clear genetic differentiation between both species with distinct genetic clusters in disjunct areas, indicating the predominant role of geographic barriers limiting gene flow. We found a remarkable shift in the climatic requirements between Pliocene and extant populations, although the niche seems to have been relatively conserved since the Pleistocene split of both species. This study highlights how an integrative approach combining different data sources and analyses, including fossils, allows solid and robust inferences about the evolutionary history of a plant group since the Pliocene.     

Ostracodes et stratigraphie du néogène et du quaternaire méditerranéens

A stratigraphical chart of marine ostracoda from Lower Miocene to Recent is established. Selected species (approximatively 220) are those morphologicaly well characterized and known from different parts of the Mediterranean area. It appears that: • lower Miocene ostracodes are still poorly known; • specific diversity is high during the Tortonian and the Lower Messinian before the complete disappearance of marine Mediterranean species during the Upper Messinian évaporitic episodes; • during the early Pliocene, about half of the Upper Miocene marine species are reintroduced with the Atlantic waters; other species migrate for the first time in the Mediterranean Sea by the same way; • at the end of the Pliocene or at the beginning of the Pleistocene several species known in Mediterranean since the Middle Miocene or before, such as Cytherella sp. gr. transversa and Ruggieria tetraptera, as well some “nordic guests” such as Hemicythere villosa and Cythere lutea, appear. This work is an opportunity to confirme a Late Miocene age for the Neogene of Skyros (Aegean Sea), to assign the “Upper Pliocene” of Terquem to the Lower Pleistocene and to refute the existence of a pliocene psychrosphere.     

New observations on the Late Miocene–Early Pliocene Lutrinae (Mustelidae: Carnivora,Mammalia) from the Middle Awash,Afar Rift,Ethiopia

New observations on the Late Miocene and Earliest Pliocene mustelids from the Middle Awash of Ethiopia are presented. The Middle Awash study area samples the last six million years of African vertebrate evolutionary history. Its Latest Miocene (Asa Koma Member of the Adu-Asa Formation, 5.54–5.77 Ma) and Earliest Pliocene (Kuseralee and Gawto Members of the Sagantole Formation, 5.2 and 4.85 Ma, respectively) deposits sample a number of large and small carnivore taxa among which mustelids are numerically abundant. Among the known Late Miocene and Early Pliocene mustelid genera, the Middle Awash Late Miocene documents the earliest Mellivora in eastern Africa and its likely first appearance in Africa, a new species of Plesiogulo, and a species of Vishnuonyx. The latter possibly represents the last appearance of this genus in Africa. Torolutra ougandensis is known from both the Late Miocene and Early Pliocene deposits of the Middle Awash. The genus Sivaonyx is represented by at least two species: S. ekecaman and S. aff. S. soriae. Most of the lutrine genera documented in the Middle Awash Late Miocene/Early Pliocene are also documented in contemporaneous sites of eastern Africa. The new observations presented here show that mustelids were more diverse in the Middle Awash Late Miocene and Early Pliocene than previously documented.     

中国晚新近纪哺乳动物群落与东亚环境变化

根据已有的中国晚新近纪哺乳动物化石记录,综合新近研究成果,初步探讨中国晚新近纪哺乳动物群落演变进程及其对于气候与环境变化的响应。结果表明,自中中新世晚期至晚中新世(约13 Ma至7-8 Ma),中国北方哺乳动物群落组成上没有明显的分异;而在其后的晚中新世晚期发生了较为明显的区域性分化,分化为东部地区以适应潮湿的较为封闭的动物群落与西部地区适应干旱的开阔环境的群落,这种分异可能与东亚夏季风的加强密切相关; 青藏高原及其周边地区化石类群的扩散与交流资料也表明由青藏高原隆升而形成的地理阻隔也可能发生在该时期;上新世哺乳动物群落演化表现出对于持续的干旱化气候背景的适应,而晚上新世某些类群的分异与主导地位的确立与该时期气候环境背景的剧烈震荡相一致。由于化石资料的不完整,时段分布的不均一,以及地理分布区域的局限,全面认识中国晚新近纪哺乳动物群落组成以及与环境变化的关系尚有很长的一段历程。     

A temporally dynamic approach for cladistic biogeography and the processes underlying the biogeographic patterns of North American deserts

We implemented a temporally dynamic approach to the cladistic biogeographic analysis of 13 areas of North American deserts and several plant and animal taxa. We undertook a parsimony analysis of paralogy‐free subtrees based on 43 phylogenetic hypotheses of arthropod, vertebrate and plant taxa, assigning their nodes to three different time slices based on their estimated minimum ages: Early‐Mid‐Miocene (23?7 Ma), Late Miocene/Pliocene (6.9?2.5 Ma) and Pleistocene (2.4?0.011 Ma). The analyses resulted in three general area cladograms, one for each time slice, showing different area relationships. They allowed us to detect influences of different geological and palaeoclimatological events of the Early‐Mid‐Miocene, Late Miocene/Pliocene and Pleistocene that might have affected the diversification of the desert biota. Several diversification events in the deserts of North America might have been driven by Neogene uplift, marine incursion and the opening of the California Gulf during the Miocene–Pliocene, whereas climatic fluctuations had the highest impact during the Pleistocene.     

ON NEW MATERIAL OF STEGODON WITH RECOLLECTIONS OF THE CLASSIFICATION OF STEGODON IN CHINA

ReviseddiagnoaisCraniumcompressedanteroposteriorlyandhighvertical1y.Superiortuskslargeandstraight,nolowerincisors'Ridge-platesprogressiveIymulti-plyingfromsixtoelevenintheintermediateteeth,fromninetofifteenandhaIfilltheposteriormolars.Thereisamediancleftoritsvestigesintheanteriorridge-platesoftheprimitivespecies.Conesrapidlysubdividingbybinaryorternary.fissionintomultipleconelets(8-l2).Ridge-plateselevatingfrombrachyodonttosubhypsodont.Cementdevelopingintheval1eys.RemarksSarwar(l977)propose…     

Geological setting of Pliocene rifting and deposition in the Afar Depression of Ethiopia

Tectonic extension of the Afar amounts to 10–30 km since 1–2 Ma and to 40–60 km since 3–5 Ma ago, or rougly 1–2 cm per year. Active faulting, volcanism, and development of the Pliocene and younger Afar grabens with their rich hominid and other vertebratefaunas, have been controlled by ENE and WNW oriented lineaments or ancient zones of structural weakness. These lineaments also controlled the alignment of the Gulf of Aden and Red Sea, respectively.Crustal stresses resulting from the late Miocene (Messinian) salinity crisis in the Mediterranean basin may have triggered renewed tectonic movements along certain pre-existing lineaments such as the Levant Shear. Separation of Africa from Arabia (and hence the inception of Afar) was controlled by tectonic events far removed from NE Africa, including possible Miocene fusion of the Indo-Arabian plates.During the early Pliocene, the Ethiopian uplands were far lower (possibly by 1000 m) and the southern Afar-Middle Awash region was higher, so that topographic and climatic contrasts between plain and plateau were less pronounced and the Afar climate was less arid than today.There was a major change from lacustrine to fluviatile deposition in the Middle Awash valley soon after 4·0–3·8 Ma ago, caused by extensional tectonics. Within the topographic constraints imposed by volcano-tectonic activity, regional climatic oscillations have controlled the detailed pattern of Pliocene (and later) sedimentation in Afar.