Abstract

The Early and Middle Jurassic plant communities of northern Iran were studied. It was observed that they both bore strong similarities. Communities with arthrophyte dominance were located in lowlands. The arborescent layer of the upper parts of the slopes and near-valley surfaces (flat interfluve?) was represented by Pityophyllum; the arborescent layer of the humid lower parts of the slopes was represented by Podozamites. Only communities of herbaceous cover differed considerably. Marattia intermedia and ?Pseudotorellia were common for the Early and Middle Jurassic. Czekanowskia ex gr. rigida, Cladophlebis denticulata, and Nilssonia obtusa, which dominated and codominated in the Early Jurassic, were replaced by N. vittaeformis, N. simplex, and Ptilophyllum pectin in the Middle Jurassic. High occurrence of the slope arborescent layer communities (in the Early Jurassic especially) suggests a prominent ruggedness of relief of near-basin parts of the land. Low occurrence of lowland herbaceous cover (especially in the Middle Jurassic) indicates underdevelopment of the valleys. The small number of stable dominants suggests that floras of the Early and Middle Jurassic of northern Iran belong to two ecoseries: Pityophyllum longifolium–Phymatoceras and Pityophyllum longifolium–Ludwigia (Ludwigella) rudis. The size of each of them is the same as a series of the general scale. The ecoseries are characterized.

中文翻译：

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伊朗北部中侏罗世的植物群落和生态地层学

摘要

对伊朗北部的侏罗纪早期和中期植物群落进行了研究。据观察，它们都具有很强的相似性。节肢动物占主导地位的社区位于低地。斜坡上部和近谷表面的树状层（平坦的插曲？）以Pityophyllum为代表；坡湿润下部的乔木层以Podozamites为代表。只有草本覆盖群落差异很大。Marattia intermedia和？假杜鹃在侏罗纪的早期和中期很常见。Czekanowskia ex gr。杜松，Cladophlebis北球，和Nilssonia扁柏在侏罗纪早期占主导地位和共占主导地位，在侏罗纪中段被N. vittaeformis，N. simplex和Ptilophyllum果胶所取代。斜坡乔木层群落的高发（特别是在侏罗纪早期）表明该地区近流域部分的起伏明显。低地草本覆盖的发生率低（特别是在中侏罗纪），表明该山谷发育不足。稳定的优势种的数量少表明伊朗北部的早，中侏罗世的那菌群属于两个ecoseries：Pityophyllum longifolium - Phymatoceras和Pityophyllum longifolium -丁香（Ludwigella）rudis。它们每个的大小与一系列的总刻度相同。生态系列的特点。