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1.
Conifer Woods of the Pliocene Age from Yunnan, China   总被引:1,自引:0,他引:1  
The Tertiary floras play an integral role in understanding the biodiversity and interactions between climate and vegetation in Yunnan, China. The fossil spores, pollen grains, and leaves in this region have been investiaged intensively. In comparison, the woods have been studied relatively little. A large number of Pliocene wood specimens was collected from the opencast lignite coal mine of Hongxing situated in Changning County of Yunnan Province. Among the collection, Tsuga cf. dumosa (D. Don) Eichler and Pinus cf. armandii Franchet were identified based on wood structures. The subtle feature oftori extensions is reported in the wood of T. cf. dumosa. Considering the climatic requirements of modern T. dumosa and P.armandii, the two species of conifer described from Pliocene sediments probably grew in mountainous terrain at an elevation of approximately 2 300 m, in a cool and humid environment.  相似文献   

2.
本文记述的18种瓢虫采自云南丽江的华山松上,其上有球蚜(Pineussp.) 寄生。包括1个新种——华山松小瓢虫Scym nus(Pullus) huashansong, sp. nov. 和1个中国新记录种——团聚丽瓢虫Adalia conglomerata (L.), 3种鉴定到属或亚属。其中的14种瓢虫同时采自铁杉,其上有铁杉球蚜(Adelges tsugae)寄生。新种华山松小瓢虫Scym nus(Pullus) huashansong (图1)体长2.65m m ,体宽1.80m m 。头黑色,口器及触角红褐色;前胸背板黑色;小盾片黑色;鞘翅红褐色。从头、前胸背板和小盾片黑色而鞘翅红褐色,该种易与它种区分;而从外生殖器而言,它与弯端小瓢虫S. (P.) accamptus Pang etPu 相似,但新种阳基较纤细,第1腹板上的后基线弯曲度大拱形明显而区分。新种模式标本1997年9月24日虞国跃采于云南丽江文笔山,存北京市农林科学院植保环保研究所。  相似文献   

3.
利用光学显微镜和扫描电镜首次对云南省楚雄州晚中新世石灰坝组石鼓村层的钙化木材进行了解剖学研究.鉴定出两种类型的木材:柳杉型落羽杉型木(Taxodioxylon cryptomeripsoides Schonfeld)和杉木型落羽杉型木(Taxodioxylon cunninghamioides Watari).二者分别与现代柳杉属和杉木属具有最接近的亲缘关系.根据这两种杉科化石木现存最近亲缘种的生态环境,并综合其他资料,推测该地区在晚中新世为温暖湿润的亚热带气候环境.  相似文献   

4.
Hadar is well known as one of the most productive early hominin sites in the world. Between 1972 and 1994 a large sample of fossil cercopithecid specimens was collected from Hadar and the nearby sites of Geraru, Ahmado, and Leadu. At least five, and possibly six, species are present in the sample, including two chronological subspecies of Theropithecus oswaldi. T. o. cf. darti is known from the Middle Pliocene deposits in the Hadar area, along with Parapapio cf. jonesi, cf. Rhinocolobus turkanaensis, and a new species of Cercopithecoides, C. meaveae. There are also isolated molars from the Middle Pliocene of a large colobine which most likely represent cf. R. turkanaensis, but may also represent another large colobine known from the nearby site of Maka in the Middle Awash. T. o. oswaldi is represented from younger deposits of Late Pliocene and Early Pleistocene age, along with the large colobine Cercopithecoides kimeui. Throughout the sequence Theropithecus oswaldi is by far the most abundant cercopithecid, with the other taxa being comparatively rare. The Parapapio material from Hadar is important as the only securely identifiable material of the genus in the East African Pliocene. Furthermore, the Hadar material includes the only associated postcranial remains for the genus. If the tentative identification of Rhinocolobus is correct, then the Hadar sample is the only known occurrence outside of the Turkana Basin. Cercopithecoides meaveae is a new species, currently only known from the Hadar region, most importantly by the associated partial skeleton from Leadu. It appears to show adaptations for terrestrial locomotion. Finally, Cercopithecoides kimeui, a very large colobine previously known from Olduvai Gorge, Koobi Fora, and Rawi is recorded from the uppermost part of the Formation.  相似文献   

5.
The palaeodiversity of flowering plants in Yunnan has been extensively interpreted from both a molecular and fossil perspective. However, for cryptogamic plants such as ferns, the palaeodiversity remains poorly known. In this study, we describe a new ferny fossil taxon, Drynaria lanpingensis sp. nov. Huang,Su et Zhou(Polypodiaceae), from the late Pliocene of northwestern Yunnan based on fragmentary frond and pinna with in situ spores. The frond is pinnatifid and the pinnae are entirely margined. The sori are arranged in one row on each side of the primary vein. The spores have a semicircular to bean-shaped equatorial view and a tuberculate surface. Taken together with previously described fossils, there are now representatives of three known fossil taxa of Drynaria from the late Pliocene of western Yunnan.These finds suggest that Drynaria diversity was considerable in the region at that time. As Drynaria is a shade-tolerant plant, growing preferably in wet conditions in the understory of forests, its extensive existence may indicate forest vegetation and humid climates in western Yunnan during the late Pliocene.This is in line with results from floristic investigations and palaeoclimatic reconstructions based on fossil floras.  相似文献   

6.
印度块菌(Tuber indicum)菌根促生细菌的研究   总被引:1,自引:1,他引:0  
【目的】筛选对印度块菌菌根量和菌根苗长势有促进作用的菌根促生细菌(Mycorrhization helper bacteria,MHB)。【方法】选择华山松为宿主植物,自块菌菌根根际土壤中分离得到的11种细菌为供试菌株,将印度块菌菌剂与不同浓度的细菌混合于特定基质中后接种于华山松上,并通过对印度块菌与华山松形成的菌根数、华山松的株高和地径三方面的统计与分析,确认MHB。【结果】Pseudomonas sp. JCM 5481 (P143)、Streptomyces sp. EN31 (S191)、Variovorax paradoxus (V633)在浓度为2.4×109 CFU/mL时对印度块菌菌根数、株高和地径均有极显著促进作用(P<0.01);Pseudomonas chlororaphis (P11)、Pseudomonas corrugate (P127)在浓度为0.8×109 CFU/mL时对印度块菌菌根数、株高和地径均有显著促进作用(P<0.05)。4种假单胞菌浓度梯度的设置显示了不同菌株适宜的浓度不同。【结论】实验获得5种MHB,并表明细菌浓度是获得MHB的一个重要影响因素。  相似文献   

7.
云南镇康大雪山常绿阔叶林群落类型的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
彭鉴 《植物生态学报》1984,8(4):294-304
常绿阔叶林在云南植被中占有重要位置,属于我国的西部类型,镇康大雪山的常绿阔叶林面积大,发育好,保存较完整,是一类具有代表性的中山湿性常绿阔叶林。本文根据常绿阔叶林的外貌、结构、成层性、优势种和生境条件特征的异同进行群落类型的划分。该地区常绿阔叶林分布较南,属于西南季风的前沿,地形复杂,山体较高,树种资源丰富,乔木优势种也较明显,生境湿润,林冠下一般具明显的竹子层片,群落类型多样,单位面积木材蓄积量较高。这类植被从自然保护研究和生产实践上具有重要的价值。  相似文献   

8.
《Palaeoworld》2021,30(3):551-561
Yunnan at southeastern margin of the Tibetan Plateau is subject to frequent wildfires each year, while its wildfire history remains poorly known due to the lack of studies on palaeofire in the region. In this study, we report a local fire from the late Pliocene of northwestern Yunnan, based on macroscopic fossil charcoals recovered from the Sanying Formation of Lanping Basin. These sedimentary charcoals exhibit silky lustre in the light and complete homogenization of adjacent xylem cell walls, characterizing the result of incomplete combustion during the late Pliocene. Our preliminary taxonomic analysis indicates that the studied charcoals are dominated by conifers, suggesting higher importance of coniferous elements as fuel sources in the fire. We assert a conifer-rich source forest for the fire event by also considering plant remains of other types, i.e., needle fragments, small shoots, fruits and seeds, from the same sampling layer. Since conifers are commonly prone to wildfires, this type of forest might have a close link with the fire by serving highly flammable fuels. We consider that the regionally seasonal drought during the late Pliocene might also take responsibility, because in the dry season forest fuels such as ground litter would become ignitable after intensive desiccation. As modern wildfires in northwestern Yunnan are closely coupled with conifer-dominant forests and seasonally dry climate, we assume this correlation might have been established by the late Pliocene. Our study may bring attention to potential roles of wildfire on local and/or regional flora and vegetation evolution in this region.  相似文献   

9.
Yunnan in southwestern China is renowned for its high plant diversity. To understand how this modern botanical richness formed, it is critical to investigate the past biodiversity throughout the geological time. In this review, we present a summary on plant diversity, floristics and climates in the Cenozoic of Yunnan and document their changes, by compiling published palaeobotanical sources. Our review demonstrates that thus far a total of 386 fossil species of ferns, gymnosperms and angiosperms belonging to 170 genera within 66 families have been reported from the Cenozoic, particularly the Neogene, of Yunnan. Angiosperms display the highest richness represented by 353 species grouped into 155 genera within 60 families, with Fagaceae, Fabaceae, Lauraceae and Juglandaceae being the most diversified. Most of the families and genera recorded as fossils still occur in Yunnan, but seven genera have disappeared, including Berryophyllum, Cedrelospermum, Cedrus, Palaeocarya, Podocarpium, Sequoia and Wataria. The regional extinction of these genera is commonly referred to an aridification of the dry season associated with Asian monsoon development. Floristic analyses indicate that in the late Miocene, Yunnan had three floristic regions: a northern subtropical floristic region in the northeast, a subtropical floristic region in the east, and a tropical floristic region in the southwest. In the late Pliocene, Yunnan saw two kinds of floristic regions: a subalpine floristic region in the northwest, and two subtropical floristic regions separately in the southwest and the eastern center. These floristic concepts are verified by results from our areal type analyses which suggest that in the Miocene southwestern Yunnan supported the most Pantropic elements, while in the Pliocene southwestern Yunnan had abundant Tropical Asia (Indo–Malaysia) type and East Asia and North America disjunct type that were absent from northwestern Yunnan. From the late Miocene to late Pliocene through to the present, floristic composition and vegetation types changed markedly, presumably in response to altitude changes and coeval global cooling. An integration of palaeoclimate data suggests that during the Neogene Yunnan was warmer and wetter than today. Moreover, northern Yunnan witnessed a pronounced temperature decline, while southern Yunnan experienced only moderate temperature changes. Summer precipitation was consistently higher than winter precipitation, suggesting a rainfall seasonality. This summary on palaeoclimates helps us to understand under what conditions plant diversity occurred and evolved in Yunnan throughout the Cenozoic.  相似文献   

10.
11.
Abstract

The fossil records of Pinus L. are abundant since the Late Cretaceous, especially for the subgenus Pinus L. (the hard pines). However, those of the subgenus Strobus (D. Don) Lemmon (the white or soft pines) are not well documented. In this study, we describe a new species of white pines, Pinus plioarmandii sp. nov., from the Pliocene of western Yunnan, southwestern China. This species mostly resembles extant P. armandii Franch. in gross morphology and cuticular structure of needles. Molecular dating showed that the Asian white pines split into two lineages around the Late Miocene, and the Pinus armandii clade diverged at the Early Pliocene. The present fossil occurrence indicates that Pinus armandii might originate in southwest China and probably in the western Yunnan. The glacial events during the Pleistocene might be the major factors for the retreat of the white pines from western Yunnan, and the rapid uplift of the Yunnan Plateau and deep incision of the river valleys since the Pliocene had posed a significant geographic barrier for their reconnection in the subsequent warm climate condition.  相似文献   

12.
为了研究在褐煤中发现的上新世云南铁杉(Pliocene Tsuga dumosa)木化石的化学成分,采用气相色谱-质谱联用技术和柱层析方法分别检测了22个挥发性成分和分离鉴定了9个化合物(1-9),化学成分类型包括烷烃(C16-C32)、脂肪酸、甾体、三萜、邻苯二甲酸酯及酚性成分。化合物结构采用波谱方法鉴定。  相似文献   

13.
对我国新生代晚期的剑齿象(Stegodon)进行再研究,提出了下列几点看法:1)依据Ste-godon的特征,可将已命名的中国剑齿象种分为3类。一类为有效的剑齿象种,包括晚中新世的S.licenti Teilhard & Trasseart,1937;上新世的S.zdanskyi Hopwood,1935和S.officinalis Hopwood,1935;上新世晚期至更新世早期的S.zhaotongensis Chow & Zhai,1962;更新世的S.chiai Chow & Zhai,1962,S.orientalis Owen,1870,S.sinensis Owen,1870和S.huananensis sp.n.等种。另一类是从剑齿象属中分出,归入到其他属或科的种。属于这一类的有可能置入真象类(Elephantoidae)的Stegodon parahypsilophus He,1984,S.guizhouensis Li & Wen,1986,Stegodon cf.S.hypsilophus和S.primitium Liu et al.,1973以及归入Stegolophodon的Ste-godon baoshanensis Yun,1975。第三类为属种分类位置未定的种,以S.wushanensis Huang et al.,1991为代表。2)南亚更新世的S.elephantoides(Clift),1828可能在我国不存在。3)我国的剑齿象化石相当丰富,发现于东经99°以东、北纬38°以南的广大地区(包括山西、陕西和甘肃以及华中、华南、西南和部分华东等地区),生存时代为晚中新世晚期至更新世。4)在新生代晚期我国的剑齿象可能经历了3次大的由北向南的扩散和迁移事件。第一次发生在晚中新世,第二次在晚中新世晚期至早上新世早期,第三次在更新世早期。5)剑齿象可能起源于亚洲。S.licenti是我国出现时代最早的剑齿象,也可能是剑齿象最原始的一种。  相似文献   

14.
三门峡地区含哺乳动物化石的几个第四纪剖面   总被引:2,自引:0,他引:2  
黄河三门峡地区的晚新生代哺乳动物化石包括了上新世至晚更新世各个层位,其中以早更新世的材料较多,有七种与泥河湾动物群是相同种;有4种与山西榆社、临猗和西侯度等地点的早更新世动物群是相同种。这说明三门峡地区早更新世动物群相当于维拉方晚期或中晚期。三门系属河湖沉积,但比黄河发育的历史为早,而黄河的沉积系贾福海等划分的第5层。为此,黄河形成的时间恐怕是早更新世之末或中更新世之初。  相似文献   

15.
New Pliocene hominoid fossils have recently been unearthed from Yuanmou county of central Yunnan province, southwestern China. This paper will provide free translation of the original chinese publications in which two new species of hominoid, a ramapithecine and a hominid were described and their associated faunas and stratigraphy. Comments on the taxonomic assignment of these fossils are presented as concluding remarks.  相似文献   

16.
Paraphyllanthoxylon abbottii n. sp. and cf. Plataninium haydenii Felix from the Paleocene Black Peaks Formation, Big Bend National Park, Texas, are the first Paleocene dicotyledonous woods described from North America. Both represent wood types common in the Cretaceous. There are 30 logs of Paraphyllanthoxylon abbottii; it is rare that a single locality has such as large number of petrified dicotyledonous logs with a similar structural pattern, and the variability in mature wood structure can be documented. Paraphyllanthoxylon abbottii has a combination of features that occurs in many dicotyledonous families, but it is most similar to genera of Burseraceae. The Big Bend Paraphyllanthoxylon trees lack distinct growth rings, which suggests they grew in a climate without marked seasonality; they have high (10–74) vulnerability indices; such high values occur in extant tropical trees. The type species of Paraphyllanthoxylon, P. arizonense Bailey was reexamined, and its quantitative features are described. Aplectotremas Serlin of Albian age from the Edwards Limestone has anatomy like Paraphyllanthoxylon, and most probably is wood from a tree. The wood designated cf. Plataninium haydenii Felix resembles extant Platanaceae but differs in having exclusively scalariform perforation plates. Comparison of this wood with other platanoid woods suggests that in platanoid woods there has been a shortening of vessel elements and a decrease in the frequency of scalariform perforation plates from the Cretaceous through the Tertiary. These changes are consistent with the Baileyan model for specialization in tracheary elements.  相似文献   

17.
We report an unusual and rich decapod crustacean assemblage from the early Pliocene (Zanclean), recently collected during the excavations of the “La Serra” quarry, located in La Serra, near San Miniato, Pisa (Toscana, central Italy). The studied specimens have been assigned, as follows: Axius sp., Callianassa chalmasii Brocchi, 1883, and Calliaxina cf. C. punica ( de Saint Laurent and Manning, 1982) (infraorder Axiidea de Saint Laurent, 1979); Gebiacantha tuscia Garassino, Pasini, De Angeli and Charbonnier sp. nov. (infraorder Gebiidea de Saint Laurent, 1979); Pagurus alatus Fabricius, 1775, and Pagurus sp. (infraorder Anomura MacLeay, 1838); Dromia neogenica Müller, 1978, Dromia sp., Medorippe cf. M. ampla Garassino, De Angeli, Gallo and Pasini, 2004, Ilia nucleus ( Linnaeus, 1758), Ristoria pliocaenica (Ristori, 1891), Pisa armata ( Latreille, 1803), Macropodia sp., Maja squinado (Herbst, 1788), Derilambrus angulifrons ( Latreille, 1825), Atelecyclus undecimdentatus (Herbst, 1783), Liocarcinus sp., Thalamita italica Garassino, Pasini, De Angeli and Charbonnier sp. nov., Pilumnus cf. P. hirtellus (Linnaeus, 1761), Eriphia cocchii Ristori, 1886, Goneplax rhomboides ( Linnaeus, 1758), Goneplax sacci Crema, 1895, (infraorder Brachyura Linnaeus, 1758). Moreover, two specimens have been assigned to callianassideans sensu lato and 13 specimens to indeterminate axiideans. Calliaxina Ngoc-Ho, 2003, Gebiacantha Ngoc-Ho, 1989, Ristoria Garassino, Pasini, De Angeli and Charbonnier gen. nov., and Macropodia Leach, 1814, are reported for the first time in the fossil record and the extant Pagurus alatus, Ilia nucleus, Pisa armata, Derilambrus angulifrons, and Pilumnus cf. P. hirtellus, are reported in the fossil record from the Pliocene. Everywhere “La Serra” quarry bio-community is very important, representing one of the richest and most diversified crustacean faunas from the Pliocene reported to date in the Mediterranean basin and worldwide, increasing notably the knowledge on the decapod populations and distribution during the early Pliocene. This community is indicative of a palaeoenvironment of shallow sublittoral water, with sandy-muddy and alternate hard shell bottom, partially covered or in proximity of seagrass, similar to the extant Mediterranean Posidonia beds, mainly inhabited by fossorial and benthonic decapods.  相似文献   

18.
秦岭火地塘林区四种主要树种凋落叶分解速率   总被引:5,自引:0,他引:5  
利用野外分解袋法对秦岭火地塘林区油松、华山松、华北落叶松、锐齿栎凋落叶的分解速率和养分释放趋势进行研究。结果表明,分解2年后,4种树种凋落叶的干物质残留率在35.6%~58.6%,残留率大小顺序为油松>华山松>华北落叶松>锐齿栎。除油松与华山松凋落叶之间残留率差异不显著外,各树种之间凋落叶分解后的残留率差异显著。在2个试验年度中,4-9月凋落叶分解最快,在其他月份保持较平稳的分解速度,分解前12个月凋落叶失重速度明显大于后12个月,呈明显的季节和阶段性差异。利用Olson模型对凋落叶分解50%和95%所需时间进行估测,结果显示,不同树种所需时间差异显著,其中锐齿栎凋落叶95%被分解所需时间最短,为5.43年,油松最长,为9.87年。凋落叶中N、P元素在分解第1年均表现出富集现象,直至1年后达到一个最高值后,开始释放,C含量则呈现出逐步下降的趋势。导致不同树种凋落叶分解速率及养分释放速率差异主要与不同凋落叶的初始质量和性质有关。  相似文献   

19.
秦岭华山松群落数量分类研究   总被引:8,自引:0,他引:8  
以秦岭华山松群落为研究对象,采用典型取样和随机取样相结合的方法在秦岭林区取400 m^2的样地36块.运用植被排表分析法和Ward最小距离聚类的方法将秦岭华山松进行了分类.结果表明,秦岭华山松群落可以分为5个群丛组7个群丛:华山松+美丽胡枝子+荩草群丛;华山松+美丽胡枝子+毛叶轴脉蕨群丛;华山松+蔷薇+崖棕群丛;华山松+短梗胡枝子+深绿蒿群丛;华山松+陕西绣线菊+香青群丛;华山松+陕西绣线菊+光蹄盖蕨群丛;华山松+蛇梅群丛.同时针对不同群丛的特点提出合理化的经营和管理措施.  相似文献   

20.
戴静  陈威兆  金露露  黄亮 《生物多样性》2022,30(11):22553-48
栎属(Quercus)植物叶片化石在新生代地层中分布普遍, 对亚热带常绿阔叶林具有重要的指示意义。本文对采自云南省宜良县上新统茨营组中的栎属植物叶片化石进行角质层结构分析, 结合叶形态特征, 系统描述了4种栎属植物: 阔叶栎(Quercus latifolia)线叶栎(Q. scottii)、楔基栎(Q. simulata)和黄毛青冈相似种(Q. cf. delavayi)。通过对比化石和现生植物的叶形态和角质层特征, 本文认为叶片形状、叶基和叶尖特征、二级脉数量、表皮细胞和垂周壁特征、气孔大小和形状、气孔密度、毛基类型、形态和分布情况可以作为区分不同种类的特征, 但是不能只考虑其中的一个因素, 应该综合这些特征作为判断依据。结合宜良植物群中其他化石资料认为, 包括壳斗科柯属(Lithocarpus)、栲属(Castanopsis)以及樟科、榆科、木兰科等在内的植物, 代表了以栎属青冈组为优势树种的半湿润常绿阔叶林。宜良植物群与同时期相近纬度的植物群相比, 植被类型相似, 但是落叶成分较少。宜良植物群中的线叶栎、楔基栎和阔叶栎同晚始新世的线叶栎以及早中新世的楔基栎和阔叶栎相比, 形态并未发生大的变化, 与现生植物也非常相似, 进一步说明云南现代常绿阔叶林的主要成分来自于古老植物的承袭, 没有发生较大的改变。  相似文献   

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