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1.
本文首次报道用离析方法研究湖北省新洲县的被子植物化石木材的情况.实验证明,经该方法处理后的木化石、导管、木射线、纤维等清晰可见,这对化石木材的研究是有意义的,并提供了一种新的辅助手段.  相似文献   

2.
The genus Sciadopitys, containing a single species (S. verticillata), is the only extant representative of the Family Sciadopityaceae (Coniferales), and is a remarkable living fossil. Although some leafy fossils have been ascribed to Sciadopityaceae, fossil xylem material with a close affinity to this family is very rare, and there have been no fossils found showing both pith and primary xylem structures, which are of great importance for wood identification. Thus, it has been difficult to use fossils for the understanding of wood anatomy evolution in the sciadopityaceous plants over geological time. In this note we briefly report on Sciadopitys-like fossil wood found in the Middle Jurassic of western Liaoning, which bears well-preserved Protosciadopityoxylon-type secondary xylem, endarch primary xylem and heterogeneous pith. This is the first report of fossil specimens of the Sciadopityaceae with such detailed preservation of wood structures. The discovery provides precise anatomical evidence for reconstructing the evolu- tionary history and geographical distribution of Sciadopityaceae, as well as contributing to understanding of the fossil diversity of the Jurassic Yanliao Flora in northern China.  相似文献   

3.
十六种速生树材的化学组分、纤维形态及制浆性能   总被引:4,自引:0,他引:4  
<正>本文报导了对水杉(Metasequoia glyptostroboides)、Ⅰ-69杨(Populus deltoidesCV.’Lux’.)、Ⅰ-72杨(P.x euramericana cv.’San Martino’)等速生材的化学组分,纤维形态以及制浆性能所作的分析和研究。在研究中,除常规分析外,还使用UV分光光度计测定了“酸溶木素”,用薄层色谱法测定了综纤维素的糖基组成,用电子显微镜观察、测定了Ⅰ-69杨、Ⅰ-72杨中的应拉木(tension wood)。此外,还采用烧碱一蒽醌法和硫酸盐法对制浆性能做了初步探索。试验结果表明:水杉、Ⅰ-69杨、Ⅰ-72杨是宜于制浆的优良的速生树种,可以考虑在造纸工业中使用。  相似文献   

4.
The Middle Jurassic Tiaojishan Formation in Beipiao City, western Liaoning comprises a variety of plant fossils including leaf impressions, compressions, permineralized rhizomes, fossil wood and dispersed spores and pollen grains. Impression and compression data suggest that the flora in the Tiaojishan Formation is dominated by Bennettitales, ferns and Nilssoniales, followed by ginkgophytes; conifers and sphenopsids are less common. Abundant permineralized rhizomes are referable to diverse taxa within fern families such as Osmundaceae and Cyatheaceae. Abundant and upright fossil stumps are common in the Tiaojishan Formation. They are well preserved with distinct growth rings and are predominatly conifers. The floristic signature of the Tiaojishan Formation indicates that subtropical to temperate warm and humid climates prevailed during the late Middle Jurassic in the Beipiao area. Growth ring pattern analysis of the fossil conifer wood demonstrates a consistent and distinct seasonal climate during this interval. The biodiversity of the remarkable Tiaojishan flora provides essential evidence for understanding the vegetation, palaeoclimate and environmental evolution of western Liaoning during the Middle to Late Jurassic.  相似文献   

5.
The Middle Jurassic Tiaojishan Formation in Beipiao City, western Liaoning comprises a variety of plant fossils including leaf impressions, compressions, permineralized rhizomes, fossil wood and dispersed spores and pollen grains. Impression and compression data suggest that the flora in the Tiaojishan Formation is dominated by Bennettitales, ferns and Nilssoniales, followed by ginkgophytes; conifers and sphenopsids are less common. Abundant permineralized rhizomes are referable to diverse taxa within fern families such as Osmundaceae and Cyatheaceae. Abundant and upright fossil stumps are common in the Tiaojishan Formation. They are well preserved with distinct growth rings and are predominatly conifers. The floristic signature of the Tiaojishan Formation indicates that subtropical to temperate warm and humid climates prevailed during the late Middle Jurassic in the Beipiao area. Growth ring pattern analysis of the fossil conifer wood demonstrates a consistent and distinct seasonal climate during this interval. The biodiversity of the remarkable Tiaojishan flora provides essential evidence for understanding the vegetation, palaeoclimate and environmental evolution of western Liaoning during the Middle to Late Jurassic.  相似文献   

6.
Mesozoic to Cenozoic petrified woods are very rich and well preserved in the Khorat Plateau, Northeast Thailand, serving as remarkable material for investigations of tropical vegetation history, paleoclimatic evolution, and paleoenvironmental changes. Our recent field survey and investigations have defined about 50 species of fossil wood assigned to 19 genera and 11 families from Mesozoic to Cenozoic deposits in this region. These woods are ascribed to two groups, gymnosperms and angiosperms. Among them, about 20 species assigned to 7 genera and 5 families are the first reports of the taxa in Thailand. The fossil wood floras indicate that during the late Mesozoic period, the tropical conifer vegetation in Northeast Thailand was dominated by the family Araucariaceae. From the Miocene to Pleistocene, a tropical climate prevailed in this region with perhaps both deciduous and evergreen broadleaf forests comprising the vegetation.  相似文献   

7.
M Godinot  M Mahboubi 《Nature》1992,357(6376):324-326
The record of early fossil Simiiformes (Anthropoidea) from the Late Eocene and Early Oligocene of Africa and the Arabian Peninsula has increased dramatically in recent years. We report here the discovery of a new, diminutive and much older (Early or Middle Eocene) simian from an Algerian locality, Glib Zegdou. This species is smaller than any other living or fossil African simiiform. Derived similarities shared with Aegyptopithecus suggest that the new genus is more closely related to propliopithecines than to oligopithecines, implying that these two subfamilies differentiated during the Early Eocene. The new discovery confirms predictions about the great antiquity of Simiiformes and emphasizes a long and endemic African history for higher primates.  相似文献   

8.
The Chengjiang fauna has played a pivotal role in our understanding of the origin and diversification of metazoans since its discovery in 1984. To date, this fauna has been documented as consisting of 121 genera with 140 species belonging to 24 phyla[1-27]. The geo- graphic distribution of the Chengjiang fauna has been expanded from Chengjiang County to eastern Yunnan Province including Haikou, Malong, Yiliang, Anning and elsewhere[25-33], with about 20 localities in to- tal[25,33]. Succes…  相似文献   

9.
Earliest Asian discoglossid frog from western Liaoning   总被引:2,自引:0,他引:2  
Based on a superbly preserved skeleton, a new anuran taxon has been named and described from the Yixian Formation (Upper Jurassic/Lower Cretaceous), Liaoning Province, northeastern China. This discovery documents the first discoglossid fossil from China, the earliest record of the group in Asia, and the only second Mesozoic discoglossid known from fully articulated material in the world. The family Discoglossidae is widely perceived as a primitive anuran group, but has no definite fossils found in collaboration with their recent distribution in Asia. The new discovery from Liaoning extends the temporal range of the group in Asia back at least 120 million years, and provides valuable fossil material for study of anatomical details of early discoglossids, as well as of historical distribution of this primitive anuran group.  相似文献   

10.
对贵阳红枫湖表层沉积物16种优控多环芳烃进行了定量分析.结果表明,红枫湖沉积物中多环芳烃总含量为273.6~944.3 ng/g,具有不利的生物影响效应,存在养殖动物的食用安全隐患;其污染来源以高温燃烧产物为主,主要由化石燃料及木材的高温燃烧废气及工业和生活废水排放等人为污染引起的.  相似文献   

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