Cycling of Labile Intermediates at the Oxic/Anoxic Interface

这次调查将是委内瑞拉大陆架上的一个自然坳陷——卡里亚科盆地碳循环时序研究的生物地球化学组成部分。由于与北部公海的横向水交换有限，该盆地的含氧地表水覆盖着广泛的缺氧水域，为研究氧化还原边界附近的有机分解提供了理想的机会。本研究将重点研究碳通量、硫酸盐还原菌和产甲烷菌对低分子脂肪酸循环的影响，以及细菌的放牧作用。后者是一类重要的发酵中间体，是Cariaco盆地缺氧有机分解下碳循环的关键中间体，应该扩展到世界海洋边缘的其他类似环境。

9415790 SCRANTON This investigation will be a biogeochemical component of a times- series study of carbon cycling in the Cariaco Basin, a nature depression on the continental shelf of Venezuela. Because of restricted lateral water exchange with the open sea to the north, this Basin with its oxygenated surface waters overlying extensive anoxic waters offers an ideal opportunity to study organic decomposition near a oxidation-reduction boundary. In particular, this study will focus on the effects of carbon flux, sulfate- reducing and methanogenic bacteria, and grazing of the bacteria on the cycling of low molecular-weight fatty acids. The latter constitute an important class of fermentation intermediates and are key intermediates in carbon cycling under anoxic organic decomposition in the Cariaco Basin and should be extensible to other similar environments on the margins of the world ocean.