ULTRASTRUCTURAL AND PALEOBIOCHEMICAL CORRELATIONS AMONG FOSSIL LEAF TISSUES FROM THE ST-MARIES RIVER (CLARKIA) AREA, NORTHERN IDAHO, USA
ULTRASTRUCTURAL AND PALEOBIOCHEMICAL CORRELATIONS AMONG FOSSIL LEAF TISSUES FROM THE ST-MARIES RIVER (CLARKIA) AREA, NORTHERN IDAHO, USA
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DOI：
10.2307/2442769
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发表时间：
1981-01-01
影响因子：
3
通讯作者：
BROWN, RM
中科院分区：
文献类型：
--
作者：
NIKLAS, KJ;BROWN, RM
中新世被子植物叶组织桦，绣球花，悬铃木，栎，栗，波斯和裸子植物组织，分别从近海和陆上湖泊沉积物，揭示了各种状态的超微结构的细节保存与他们的古生物化学配置文件。近海组织样品中膜结合细胞器的良好细胞学保存与相对温和的叶绿素和脂肪酸降解（二氯酚，不饱和烃）相关，而在陆上标本中看到的超微结构的逐步恶化是伴随着广泛的叶绿素降解和饱和烃。在火山碎屑（Succor Creek植物群，中新世）和湖泊（Clarkia植物群）环境中发现的化石之间的比较研究表明，沉积前和沉积后的组织水合作用的程度是一个不太重要的因素，在确定保存比氧化还原电位和次生代谢产物（单宁酸，叶绿素衍生物）。叶组织中的细胞器降解的序列，显然叶绿体和细胞壁是最稳定的细胞成分，而内质网，细胞核和线粒体是最不稳定的。
Miocene angiosperm leaf tissues of Betula, Hydrangea, Platanus, Quercus, Castanea, Persea and gymnospermous tissues from offshore and onshore lacustrine sediments, respectively, reveal various states of ultrastructural detail in preservation which correlate with their paleobiochemical profiles. Excellent cytologic preservation of membrane-bound organelles in offshore tissue samples is correlated with relatively mild chlorophyll and fatty acid degradation (chlorins, unsaturated hydrocarbons), while progressive deterioration of ultrastructure seen in onshore specimens is concomitant with extensive chlorophyll degradation and saturation of hydrocarbons. Comparative studies between fossils found in pyroclastic (Succor Creek Flora, Miocene) and lacustrine (Clarkia Flora) environments indicate that the degree of pre- and post-depositional hydration of tissues is a less significant factor in determining preservation than redox potential and secondary metabolites (tannic acids, chlorophyll derivatives). A sequence of organelle degradation in leaf tissues is given; apparently chloroplasts and cell walls are the most stable cellular constituents, while the endoplasmic reticulum, nuclei and mitochondria are the most labile.