Dissertation Research: Identifying the Sources and Ages of Organic Matter Supporting Estuarine Bacterial Production: A Novel Multiple Isotope Approach

00- 73243 Ducklow/McCallisterDDIG：确定支持河口细菌生产的有机物的来源和年龄：一种新的多同位素方法土地利用模式长期变化的影响集中在沿海地区。这些变化从根本上改变了河流有机物输出到河口的规模和组成。这反过来又有可能改变水柱中生产和呼吸之间的代谢平衡。这项研究将有助于确定细菌在调节河口代谢平衡的作用，通过检查的粒度组分，来源和年龄的河口溶解有机物（DOM）纳入细菌生物量的约克河口（一个子河口的切萨皮克湾）。此外，PI将实验研究DOM的分数，可以代谢的河口停留时间的时间尺度上。研究人员将采用一种新的方法，涉及多种同位素，以克服这一领域研究的传统方法局限性。

00-73243Ducklow/McCallisterDDIG: Identifying the sources and ages of organic matter supporting estuarine bacterial production: A novel multiple isotope approachThe effects of long-term changes in land use patterns are focused in the coastal zone. These changes have fundamentally altered both the magnitude and composition of riverine organic matter exported to the estuary. This, in turn, has the potential to shift the metabolic balance between production and respiration in the water column. This study will help to determine the role of bacteria in regulating estuarine metabolic balance by examining the size fractions, sources, and ages of estuarine dissolved organic matter (DOM) incorporated into bacterial biomass in the York River Estuary (a sub-estuary of the Chesapeake Bay). In addition, the PIs will experimentally investigate the fraction of DOM which can be metabolized on the time scale of estuarine residence times. The investigators will employ a novel approach, involving a multiple isotope, to overcome the traditional methodological limitations of research in this area.