![]() ![]() Differences in the response sensitivity of stomatal index to atmospheric CO 2 among four genera of Cupressaceae conifers. Stomatal frequency adjustment of four conifer species to historical changes in atmospheric CO 2. Kouwenberg L L R, McElwain J C, Kürschner W M, et al. Fossil Plants and Spores: Modern Techniques. Stomatal density and index: the practice. On the causes and ecological significance of stomatal frequency, with special reference to the woodland flora. Stomatal numbers are sensitive to increases in CO 2 concentration from pre-industral levels. Re-investigation of the occurrence of cutan in plants: Implications for the leaf fossil record. Gupta N S, Briggs D E G, Collinson M E, et al. ![]() Molecular taphonomy of animal and plant cuticles: Selective preservation and diagenesis. Analysis of modern and fossil plant cuticles by Curie point Py-GC and Curie point Py-GC-MS: Recognition of a new, highly aliphatic and resistant biopolymer. ![]() The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.Ĭutler D F, Alvin K L, Price C E, eds. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. glyptostroboides, as a comparative reference, has been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living representative, M. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Here, we describe a new method using clear nail polish as a medium to “strengthen” the originally thin and fragile cuticles prior to maceration procedures. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeoclimatological research. ![]() However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO 2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. The research is also supported by the Senckenberg Nature Museum in Germany.Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon-struction. Study of its fossils will enable researchers to understand how conifer plants distribute spatially and respond to climate changeĪs the first Metasequoia fossil in southwest China and the southernmost fossil of the genus around the world, the newfound fossils considerably expands the spatial distribution range of Metasequoia in the geological past.Īccording to the research published in Review of Palaeobotany and Palynology, the disappearance of Metasequoia in southwest China might be related to the evolutionary stasis of Metasequoia, most likely preventing necessary adaptations to increasing winter and spring aridity induced by the intensification of the Asian monsoon in this region during the Neogene. The Metasequoia is an ancient plant with a narrow natural distribution in central China. Numerous well-preserved leafy shoots and seed cones of Metasequoia have been brought to light after a deep sleep of between about 16-11 million years ago at the middle Miocene deposits in Sanzhangtian village, southwest China's Yunnan Province, by researchers from Xishuangbanna Tropical Botanical Garden. BEIJING, April 6 (Xinhua) - Chinese researchers have discovered a Metasequoia fossil in southwest China, the furthest south such a fossil that has ever been discovered, revealing a possible cause for the Metasequoia's disappearance in the region. ![]()
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