The paper presents data on the composition of organic matter (OM) in the surface layer of bottom sediments (BS) in two small estuaries in the southwestern part of the Tatar Strait (as of summer of 2014 and 2016). The concentration of hydrocarbons (HC) varied from 0.01 to 2.0 mg/g. The HC content in the uniform silt–psammite sediments (0.55–1.47 mg/g) was higher than the biogenic background level (≈0.1 mg/g). The percentage of HC carbon of total Corg (TOC) in the sediments of Muchke Lake (2.68% on average) was much higher than that in Toki Lake and than the value of ≤1% assumed as an indicator of the absence of a hydrocarbon load. The percentage of autochthonous OM (determined from the chlorophyll a content) in the sediments of weakly flowing Muchke Lake is 41% of TOC, and the value for flowing Toki Lake is 18%. The data obtained in the course of this study are consistent with the molecular composition of the n-alkanes: the OM of Muchke Lake is dominated by that of hydrobiont origin, whereas the OM of Toki Lake consists mostly of terrigenous–humic compounds. The n-alkanes contain much compounds typically produced by bacterial synthesis, which indicates that microorganisms played an important role in forming the hydrocarbon background of sediments in the small estuaries.

中文翻译：

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鞑靼海峡小河口底泥烃背景来源及生成参数

本文提供了鞑靼海峡西南部两个小河口底部沉积物 (BS) 表层有机质 (OM) 组成的数据（截至 2014 年和 2016 年夏季）。碳氢化合物 (HC) 的浓度从 0.01 到 2.0 毫克/克不等。均匀粉砂-砂岩沉积物中的 HC 含量（0.55-1.47 mg/g）高于生物背景水平（≈0.1 mg/g）。木克湖沉积物中总 Corg (TOC) 的 HC 碳百分比（平均 2.68%）远高于 Toki 湖，并且低于 ≤1% 的假设值作为不存在烃负荷的指标. 微弱流动的木克湖沉积物中原生有机质的百分比（由叶绿素a含量确定）为TOC的41%，流动的Toki湖值为18%。本研究过程中获得的数据与正构烷烃的分子组成一致：Muchke 湖的 OM 以水生生物为主，而 Toki 湖的 OM 主要由陆源腐殖质化合物组成。正构烷烃中含有很多通常由细菌合成产生的化合物，这表明微生物在小河口沉积物的烃背景形成中发挥了重要作用。