山东五图含煤岩系孢粉组合及其地层意义     

王晓梅  王明镇  张锡麒 《地层学杂志》2005,29(1):22-27

对五图组含煤岩系进行研究 ,所揭示的孢粉植物群中 ,被子植物榆粉 (Dlmipollenites)和栎粉 (Quercoidites)有很高的含量 ,此外有山核桃粉 (Caryapollenites)、朴粉 (Celtipollenites)、枫杨粉 (Pterocaryapollenites)、胡桃粉(Juglanspollenites)、桦粉 (Betulaepollenites)、苗榆粉 (Ostryoipollenites)、枥粉 (Carpinipites)和小栗粉 (Cupuliferoipollenites)等 ,其中热带、亚热带分子占很大的比重 ,且有很高的分异度 ;裸子植物含量不高 ,主要为松粉(Pinuspollenites)和云杉粉 (Piceaepollenites) ,其次为杉粉 (Taxodiaceaepollenites)和麻黄粉 (Ephedripites) ;蕨类孢子一般含量较少 ,仅在部分样品中三角孢 (Deltoidospora)含量很高。在参考沉积、古气候、海平面变化以及其他门类化石资料的基础上 ,对孢粉化石群的时代归属及我国东部区域相关问题作了讨论 ,得出五图组孢粉组合特征与其他古生物资料所得的时代意见一致 ,属早始新世晚期到中始新世早期 ,其古气候特征也与全球海洋气候特征相符合。  相似文献   

从秦岭蕨类植物区系地理成分论秦岭山地生态分界线的划分   总被引：6，自引：0，他引：6  

王菁兰  刘全儒  孟世勇  赵鸣飞  康慕谊 《地理研究》2010,29(9):1629-1638

依据2007~2008年野外实地调查以及相关文献资料,运用植物区系地理学和数量生态学方法,分析了秦岭蕨类植物区系的物种组成和地理分布特征,划分了秦岭蕨类植物的垂直带谱,并以此为基础探讨了秦岭山地生态分界线的划分,得出以下主要结论:(1)秦岭共有蕨类植物36科85属311种,优势科为鳞毛蕨科、蹄盖蕨科和水龙骨科,优势属为鳞毛蕨属和耳蕨属;在科属水平上,以热带成分占优势;而种的水平则以温带成分占绝对优势。(2)根据秦岭蕨类植物南北坡垂直带谱的对比分析,南坡海拔1000m左右应该是一条重要的生态分界线。(3)南坡1000m以下蕨类植物区系组成更接近亚热带区系,而其他地带则与温带蕨类植物区系更为接近,DCA排序很好地证明了此结果。综合来看,将南坡海拔1000m作为秦岭山地亚热带与暖温带的生态分界线较为科学。  相似文献   

小五台山自然保护区苔藓植物研究   总被引：4，自引：0，他引：4  

李敏  赵建成  王立宝 《地理与地理信息科学》2004,20(2):109-112

根据对小五台山国家级自然保护区苔藓植物资源的实地调查和室内鉴定,该文分析了保护区内苔藓植物区系的基本组成,统计了科、属、种的数目及其优势科、属;讨论了苔藓植物的10种区系成分及其区系特征,其中北温带成分居主导地位,针对苔藓植物资源的现状,提出合理开发利用的建议。  相似文献   

中国更新世环境巨变的孢粉植物群记录   总被引：4，自引：1，他引：3  

童国榜  陈云  吴锡浩  李铮华  杨振京  王书兵  曹家栋 《地质力学学报》1999,5(4):11-21

通过对已有３８个剖面的孢粉时间序列分析,探讨了１．６ＭａＢＰ－０．８ＭａＢＰ的植被与环境巨变,划分出两个孢粉带及两个孢粉气候事件,提出该时段是更新世环境最恶劣的时期该时期植被稀疏,北方一般以森林草原和草原为主,西北地区出现荒漠或荒漠草原,南方以森林及灌丛草原为主,表明当时气候冷干,降温幅度可达１５－１７℃,降水量减少３００－５００ｍｍ。  相似文献   

吉林省延边地区二叠纪的三类植物群与古陆缘再造   总被引：10，自引：0，他引：10  

彭玉鲸  刘爱 《吉林地质》1999,18(1):1-12

吉林省延边地区早二叠世晚期－晚二叠世早期存在着开山屯、解放村、青沟子等二处不同类型的植物群、前者属华夏植物群,中间为华夏与安加拉混生植物群,后者则是安 拉植物群,反映出和龙地块北部陆缘活动带、兴凯地块西部陆缘活动带、佳木斯地块东南部陆缘活带达三者鼎足而立的古地理展布格局。阐明这三类不同植物群的古植物地理区的属性,不仅藉以证明上三地块间各自陆缘活动带的存在及其相互关系,且将为解决延边地区争论至今的二  相似文献   

热带水库消落区植物群落物种组成与结构特征——以海南松涛水库为例     

丁扬  姜百惠  丁鑫  杨帆  孙涛 《湖泊科学》2018,30(6):1745-1754

消落区是河流、湖泊和水库因阶段性或长期性的水位涨落而反复淹没或出露而形成的一种特殊的季节性湿地.消落区植被在维持水陆生态系统的动态平衡、生物多样性、生态安全及生态服务功能等方面发挥着重要作用.通过样方法调查分析了海南松涛水库消落区植物组成、区系特点以及群落分布特征.结果显示：松涛水库消落区共有维管植物40科101属115种,其中被子植物36科97属111种,蕨类植物4科4属4种.植物区系以热带性为主,外来入侵种较多,且既耐水淹又耐干旱植物众多;群落以草本、灌木植物为主,乔木较少且大多以幼苗形式存在.主要群落类型为以铺地黍（Panicum repens）为优势种的复合群落,个别区域零散分布有美洲蟛蜞菊（Wedelia trilobata）、光荚含羞草（Mimosa sepiaria）、猪屎豆（Crotalaria pallida）、马松子（Melochia corchorifolia）、假臭草（Praxelis clematidea）和铺地黍等单优群落.消落区不同海拔区间群落分布存在明显差异,物种多样性从高到低呈显著递减趋势.研究结果可为松涛水库消落区植被恢复工作提供科学指导.  相似文献   

甘肃省宝积山晚三叠世植物群与古地理研究   总被引：1，自引：0，他引：1  

阎同生 《地理与地理信息科学》2006,22(1):103-108

晚三叠世地层是我国西北的主要产煤产油地层,对甘肃省宝积山晚三叠世植物群及古地理进行研究,发现植物群31属56种。其中真蕨类植物7属16种,有节类植物4属10种,种子蕨类植物2属2种,苏铁类植物5属7种,银杏类植物6属13种,松柏类植物2属3种,裸子植物种子化石3属3种,分类位置不明化石2属2种,发现了多实拟丹尼蕨和蔡耶贝尔瑙蕨两种北方植物群的典型代表。植物生态类型主要为滨岸、高地和低地。依据纵向分布特点,可将宝积山植物群划分为多实拟丹尼蕨(Danaeopsis fecunda)—周氏似银杏(Ginkgoites chowi)和巨大枝脉蕨(Cladophlebiscf.gigantea)—蟹形新芦木(Neocalamites carcinoides)两个组合带。当时的古气候应为亚热带,通过对沉积物分析确定古环境出现过多次变化,将上三叠统划分为5个古地理演化阶段,可与邻区进行对比。  相似文献   

A New Lycopsid, Zhenglia radiata gen. et sp. nov., from the Lower Devonian Posongchong Formation of Southeastern Yunnan, China, and Its Evolutionary Significance     

HAO Shougang WANG Deming WANG Qi XUE Jinzhuang 《《地质学报》英文版》2006,80(1):11-19

A new plant, Zhenglia radiata gen. et sp. nov., from the Posongchong Formation （Early Devonian, Pragian age） of the Wenshan District of southeastern Yunnan Province, China is a small herbaceous lycopsid. The aerial branches divide into foliar and fertile stems. The arrangement of the leaf bases on the stem shows lepidodendroid-like phyllotaxy. Possibly the leaf base bears a ligulate pit. The microphyll consists of a swollen, decurrent base, and an entire, linear lamina. The fertile axis is composed of sporophylls arranged helically, forming a compact area similar to cone-like structure. Each sporophyll consists of a widened lateral extension and a distal lamina. The ovoid-elongate sporangia are attached adaxially on the surface of sporophylls. Based on morphological similarities, especially the undivided microphylls, the style of phyllotaxy, the form of the cone-like structures and sporangia, the new lycopsid Zhenglia radiata is placed in the order Protolepidodendrales and a possible evolutionary relationship with the arborescent lycopsids of the Late Devonian and Carboniferous is considered.  相似文献   

Hooked: Habits of the Chinese Permian gigantopterid Gigantonoclea     

《Journal of Asian Earth Sciences》2014

Based upon anatomical evidence, Permian aged gigantopterid fossils are in general reconstructed as climbing or scrambling plants. Gigantonoclea, a genus of adpressed gigantopterid foliage from the Permian of northern China, has been reported to co-occur with hook-like organs that were interpreted as indicating a scrambling/climbing habit. We reinvestigated these hook-like structures and re-evaluated the nature of the co-occurrences in context with the flora preserved in each plant-bearing fossil ‘bed’ in the North China sedimentary succession. New findings show that the species Gigantonoclea hallei probably climbed using specially adapted clusters of compound grappling hook-like shoots borne on the stems. This structural arrangement comprising shoots of hooks is new to the scrambling/climbing concept in gigantopterids. However, a key figured specimen previously reported as showing intermediate hook-tipped leaf morphology on a sole pinnule tip is discounted as such and is reinterpreted as a ‘normal’ pinnule partially hidden under sediment that results in an unusual appearance to this pinnule tip. Adaptations for climbing or scrambling based upon ‘hooked leaves’ observed in Gigantonoclea lagrelii are no longer supported and are reinterpreted as incompletely expanded leaves where the vernation process was interrupted. These data weaken prior interpretations of G. lagrelii as a climber/scrambler and raise doubts about the ubiquity of hooks amongst the gigantopterids as structures enabling them to climb or scramble their way through the Permian world.  相似文献   

Early Jurassic Flora and Stratigraphy from Shansonggang of Southern Jilin,China     

Fengxiang Liu  Yuewu Sun  Chunlin Sun  Jiansheng Lu  Yanhua Zhao 《东北亚地学研究》2003,(1)

1IntroductionThe Shansonggang Basin, one of the Mesozoic coal-bearing basins in northeastern China, is located in southern Jilin Province, China and covering about 30 km2(Fig.1). The basin is lying in the northwest-ern margin of the Longgang anticline, just opposite to the Yihe Basin which lies in the southeastern margin of the anticline. During 1940s~1970 s, a lot of work on the survey of coal geology was made in the basin, but there has been a little knowledge about the plant fossils…  相似文献