Department of Hydrobiology, Universidad Autónoma Metropolitana-Iztapalapa, Colonia Vicentina, Mexico City, Mexico.
Archaea. 2013;2013:582646. doi: 10.1155/2013/582646. Epub 2013 Jan 17.
Methanogenesis may represent a key process in the terminal phases of anaerobic organic matter mineralization in sediments of coastal lagoons. The aim of the present work was to study the temporal and spatial dynamics of methanogenic archaea in sediments of tropical coastal lagoons and their relationship with environmental changes in order to determine how these influence methanogenic community. Sediment samples were collected during the dry (February, May, and early June) and rainy seasons (July, October, and November). Microbiological analysis included the quantification of viable methanogenic archaea (MA) with three substrates and the evaluation of kinetic activity from acetate in the presence and absence of sulfate. The environmental variables assessed were temperature, pH, Eh, salinity, sulfate, solids content, organic carbon, and carbohydrates. MA abundance was significantly higher in the rainy season (10(6)-10(7) cells/g) compared with the dry season (10(4)-10(6) cells/g), with methanol as an important substrate. At spatial level, MA were detected in the two layers analyzed, and no important variations were observed either in MA abundance or activity. Salinity, sulfate, solids, organic carbon, and Eh were the environmental variables related to methanogenic community. A conceptual model is proposed to explain the dynamics of the MA.
产甲烷作用可能是沿海泻湖沉积物中厌氧有机物质矿化的末端阶段的关键过程。本研究的目的是研究热带沿海泻湖沉积物中产甲烷古菌的时空动态及其与环境变化的关系，以确定这些因素如何影响产甲烷群落。在旱季（2 月、5 月和 6 月初）和雨季（7 月、10 月和 11 月）采集了沉积物样品。微生物学分析包括用三种底物定量测定可培养的产甲烷古菌（MA），并在有硫酸盐和无硫酸盐的情况下评估乙酸盐的动力学活性。评估的环境变量包括温度、pH 值、Eh 值、盐度、硫酸盐、固体含量、有机碳和碳水化合物。与旱季（10(4)-10(6) 个细胞/g）相比，雨季（10(6)-10(7) 个细胞/g）中 MA 的丰度明显更高，甲醇是重要的底物。在空间水平上，在分析的两个层中都检测到了 MA，MA 的丰度和活性均无明显变化。盐度、硫酸盐、固体、有机碳和 Eh 是与产甲烷群落相关的环境变量。提出了一个概念模型来解释 MA 的动态。
