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长链烯酮已被广泛运用于古气候/古环境的重建工作,对古海洋环境的重建尤为成功.最近几年里文献报到了长链烯酮存在于很多湖泊里.因此运用湖相烯酮重建陆相环境变迁有很大潜力.我们在这里总结已发现的世界及中国范围内的湖泊烯酮,并通过比较(1)是否存在C37:4烯酮(2)C37与C38烯酮的比值(3)是否存在C38甲基烯酮,来评价湖相烯酮的组成特征是否有别于海相烯酮.我们也讨论在某些情况下湖相样品里一些干扰峰的存在会导致湖相烯酮的分布特征不能准确地鉴定.我们认为湖相烯酮的分布特征的确有别于海相烯酮,这样的区别可用于指示当时的沉积环境. “,”Long-chain alkenones have been used widely for reconstructions of paleoclimatological and paleoenvironmental changes, especially in marine environments. Over the last few years, the number of reported cases with alkenones found in lacustrine settings has increased dramatically, providing great potential to be used for terrestrial environmental studies. Here we review the reported occurrences of alkenones from lakes in China and around the world. We then evaluate whether alkenone composition patterns in lakes are distinct from those in marine settings, by comparing their three features: (1) the presence of tetra-unsaturated C37 alkenone (C37:4), (2) the ratio of C37 over C38 contents (C37/C38), and (3) the lack of di- and tri-unsaturated methyl C38 alkenones (C38:3ME and C38:2ME). We also discuss that in some cases confounding compounds in lacustrine samples could interfere with alkenone peaks and thus could affect the identification of composition patterns. We conclude that alkenone composition patterns in lacustrine settings indeed differ from those in open oceans, which could be used to indicate depositional environments.