Sedimentary Microbiological Communities Across the Equatorial Pacific Carbon-Flux Gradient: Biomass, Composition, Carbon-Utilization Rates, and Production

中赤道太平洋（EQPAC）是一个总体初级生产力很高的非常大的区域，在从地表水到海底的有机物质通量中表现出明显的纬度梯度。模拟全球碳收支的一个问题是，该地区海底有机碳矿化率与地表生产力没有直接关系。因此，需要更好地了解控制从地表水下降的有机物破坏的过程。在这方面，研究沉积微生物，特别是细菌的作用至关重要。该项目将于1992年在USJGOFS EQPAC巡航上对微生物群落进行取样。该研究将采用多方面的方法，以解决与底栖环境碳通量变化对以下四个方面的影响有关的假设：1)沉积微生物生物量；2)微生物群落的官能团组成；3)细菌利用碳（谷氨酸）；4)微生物群落的生长速率和生产力。该项目的最终目标是将这些微生物数据与其他EQPAC研究人员获得的数据结合起来，确定细菌在这些海洋沉积物中有机物的矿化和形成中的作用。

The central equatorial Pacific (EQPAC) is a very large region of overall high primary productivity that exhibits distinct latitudinal gradients in the flux of organic material from surface waters to the seafloor. A problem in modeling global carbon budgets is that the rate of organic-carbon mineralization at the seafloor in this region is not directly related to surface productivity. Therefore, a better understanding is needed of the processes controlling the destruction of organic matter falling from surface waters. In this regard, it is critical to study the role of sedimentary microorganisms, especially bacteria. This project will sample the microbiological communities on a USJGOFS EQPAC cruise in 1992. The study will employ a multifaceted approach will be used in order to address four hypotheses concerned with the effects of changes in carbon flux to the benthic environment on: 1) sedimentary microbial biomass; 2) the functional-group composition of the microbial community; 3) bacterial utilization of carbon (glutamic acid); 4) the growth rate and productivity of the microbial community. An ultimate goal of this project is to combine these microbiological data with those generated by other EQPAC researchers and to determine the role of bacteria in the mineralization and formation of organic matter in these oceanic sediments.