Trees on the side directly exposed to sunlight generally grow faster than on the opposite side, a phenomenon termed plant phototropism. There are in situ vertical trunks of silicified wood in the Xiadelongwan area of ...Trees on the side directly exposed to sunlight generally grow faster than on the opposite side, a phenomenon termed plant phototropism. There are in situ vertical trunks of silicified wood in the Xiadelongwan area of Yanqing County, north Beijing, where the first National Geologic Park of Petrified Wood of China has been built since 2002. A few trunks have well-preserved growth rings. One petrified stump from the formation shows a positive phototropism direction of SW230°. As compared with the modern normal growth stumps in Beijing plain area, which have a positive phototropism direction of SW210 °± 5°, the evidence of wood phototropism supports the conclusion of previous palaeomagnetic studies that the North China Plate has rotated clockwise since the Late Jurassic. The known petrified wood stumps in the Yanshan-Liaoning area are mainly found from the strata of 165-136 Ma, which corresponds to the main stage of the Yanshanian Movement.展开更多
Objective The Yan-Liao Aulacogen is located in the northern SinoKorean Plate,buried under huge Meso-Neoproterozoic sedimentation,and is widely distributed in Beijing,Tianjin and Hebei.In these strata,several microbial...Objective The Yan-Liao Aulacogen is located in the northern SinoKorean Plate,buried under huge Meso-Neoproterozoic sedimentation,and is widely distributed in Beijing,Tianjin and Hebei.In these strata,several microbial mats occur,represented by four stromatolite assemblages within the Upper Precambrian stratotype section at Jixian,Tianjin.展开更多
Objective Plant phototropism means that trees on the side directly exposed to sunlight generally grow faster than those on the opposite,and positive phototropism is easy to observe in crown and trunk.In this study,we ...Objective Plant phototropism means that trees on the side directly exposed to sunlight generally grow faster than those on the opposite,and positive phototropism is easy to observe in crown and trunk.In this study,we chose the transverse section of tree trunk to observe.The definitive intensity of plant phototropism ranges regularly from strong to weak and finally disappeared along with the latitudinal change from high to low.展开更多
Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the ...Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.展开更多
Permineralized osmundaceous rhizome with anatomical and phylogenetic information plays a significant role in understanding the origin,evolution,and diversity variation of the fern family Osmundaceae in geological hist...Permineralized osmundaceous rhizome with anatomical and phylogenetic information plays a significant role in understanding the origin,evolution,and diversity variation of the fern family Osmundaceae in geological history.The northern Hebei and western Liaoning region is one of the most important fossil localities for the Jurassic osmundaceous rhizome fossils in the Northern Hemisphere;however,the diversity character of osmundaceous rhizome fossil remains poorly known.A new structurally preserved fern rhizome species,Ashicaulis wangii sp.nov.,is described from the Middle Jurassic Tiaojishan Formation in Beipiao City,Liaoning Province,northeastern China.The rhizome is composed of heterogeneous pith,an ectophloic–dictyoxylic siphonostele,a two–layered cortex,and a mantle of adventitious roots and petiole bases.The xylem cylinder,with complete leaf gaps,consists of 15–17 xylem strands.The petiole base is characterized by a heterogeneous sclerotic ring and numerous sclerenchyma masses in the petiolar cortex.Among five known Ashicaulis species with heterogeneous sclerotic ring,four of them are documented from China.Therefore,osmundaceous rhizome fossils from China show endemic anatomical characteristics and significances for palaeobiogeography.Comparisons of anatomical features suggest that A.wangii sp.nov.bears close similarities to Osmunda pluma Miller from the Paleocene of Dakota,USA.Fossil species of A.wangii provides new evidence for further understanding the species diversity of osmundaceous rhizome fossil in China and in the Northern Hemisphere,and contributes to exploring the macroevolution process of the Mesozoic osmundaceous plants.展开更多
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 ...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.展开更多
基金jointly supported by State Key Program of Basic Research of Ministry of Science and Technology,China(Grant No.2012CB822003)the National Natural Science Foundation of China(Grant Nos. 41402004,41272010)the Team Program of Scientific Innovation and Interdisciplinary Cooperation of CAS
文摘Trees on the side directly exposed to sunlight generally grow faster than on the opposite side, a phenomenon termed plant phototropism. There are in situ vertical trunks of silicified wood in the Xiadelongwan area of Yanqing County, north Beijing, where the first National Geologic Park of Petrified Wood of China has been built since 2002. A few trunks have well-preserved growth rings. One petrified stump from the formation shows a positive phototropism direction of SW230°. As compared with the modern normal growth stumps in Beijing plain area, which have a positive phototropism direction of SW210 °± 5°, the evidence of wood phototropism supports the conclusion of previous palaeomagnetic studies that the North China Plate has rotated clockwise since the Late Jurassic. The known petrified wood stumps in the Yanshan-Liaoning area are mainly found from the strata of 165-136 Ma, which corresponds to the main stage of the Yanshanian Movement.
基金financially supported by the CAGS Research Fund (grant No.YWF201608)the National Natural Sciences Foundation of China (grant No.NSFC 41402004)
文摘Objective The Yan-Liao Aulacogen is located in the northern SinoKorean Plate,buried under huge Meso-Neoproterozoic sedimentation,and is widely distributed in Beijing,Tianjin and Hebei.In these strata,several microbial mats occur,represented by four stromatolite assemblages within the Upper Precambrian stratotype section at Jixian,Tianjin.
基金financially supported by the National Natural Sciences Foundation of China (grants No.41402004,41272010,41572014 and 41302004)the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (grant No.XDB18000000)+1 种基金the State Key Program of Research and Development of Ministry of Science and Technology,China (grant No.2016YFC0600406)the Team Program of Scientific Innovation and Interdisciplinary Cooperation of CAS
文摘Objective Plant phototropism means that trees on the side directly exposed to sunlight generally grow faster than those on the opposite,and positive phototropism is easy to observe in crown and trunk.In this study,we chose the transverse section of tree trunk to observe.The definitive intensity of plant phototropism ranges regularly from strong to weak and finally disappeared along with the latitudinal change from high to low.
基金jointly supported by the State Key Program of Basic Research of Ministry of Science and TechnologyChina(Grant No.2012CB822003)+10 种基金the National Natural Science Foundation of China(Grant Nos.412720104130200441172026&41402004)the Team Program of Scientific Innovation and Interdisciplinary Cooperation of CASthe Natural Science Foundation(Grant No.201102199)Education Bureau Foundation(Grant No.LR2012038)of Liaoning Province\the State Key Laboratory of Palaeobiology and Stratigraphy(NIGPASCAS)(Grant No.133113)Science Research Project of Liaoning Provincial Education Department(Grant No.L2012391)the Talent Fund of Shenyang Normal University(Grant No.91400114006)the Provincial Training Programs of Innovation and Entrepreneurship for Undergraduates of Liaoning(Grant No.201310166058)
文摘Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.
基金jointly supported by State Key Programme of Basic Research of Ministry of Science and Technology,China(Grant No.2012CB822003)the National Natural Science Foundation of China(Grant Nos.41272010,41302004&40972008)+4 种基金the Innovation Project of CAS(Grant No.KZCX-2-YW-154)the Team Program of Scientific Innovation and Interdisciplinary Cooperation of CASthe State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS)(Grant No.133113)Science Research Project of Liaoning Provincial Education Department(Grant No.L2012391)the Doctoral Fund of Shenyang Normal University
文摘Permineralized osmundaceous rhizome with anatomical and phylogenetic information plays a significant role in understanding the origin,evolution,and diversity variation of the fern family Osmundaceae in geological history.The northern Hebei and western Liaoning region is one of the most important fossil localities for the Jurassic osmundaceous rhizome fossils in the Northern Hemisphere;however,the diversity character of osmundaceous rhizome fossil remains poorly known.A new structurally preserved fern rhizome species,Ashicaulis wangii sp.nov.,is described from the Middle Jurassic Tiaojishan Formation in Beipiao City,Liaoning Province,northeastern China.The rhizome is composed of heterogeneous pith,an ectophloic–dictyoxylic siphonostele,a two–layered cortex,and a mantle of adventitious roots and petiole bases.The xylem cylinder,with complete leaf gaps,consists of 15–17 xylem strands.The petiole base is characterized by a heterogeneous sclerotic ring and numerous sclerenchyma masses in the petiolar cortex.Among five known Ashicaulis species with heterogeneous sclerotic ring,four of them are documented from China.Therefore,osmundaceous rhizome fossils from China show endemic anatomical characteristics and significances for palaeobiogeography.Comparisons of anatomical features suggest that A.wangii sp.nov.bears close similarities to Osmunda pluma Miller from the Paleocene of Dakota,USA.Fossil species of A.wangii provides new evidence for further understanding the species diversity of osmundaceous rhizome fossil in China and in the Northern Hemisphere,and contributes to exploring the macroevolution process of the Mesozoic osmundaceous plants.
基金supported by the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX-2-YW-154)the National Basic Research Program of China(2012CB822000 and 2006CB701401)+1 种基金the National Natural Science Foundation of China (40972008, 40472004 and J0930006)UNESCO-IUGS Project IGCP 506
文摘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.
