Effect of Sediment Transport on Benthic Bacterial Growth andExoenzyme Production

据信刺激海洋沉积物中细菌的因素， 因此，加强它们在底栖生物群落中的作用， 养分循环，包括增加养分供应，放牧 压力和物理运输事件。 德明博士的研究 将确定泥沙输运对两个关键的 细菌参数、生长和胞外酶产生， 最初是简单的，逐渐变得复杂 模拟：静态（单核）、梯度静态（多核 在营养梯度上串联），以及水动力学 （水槽）微观世界。 增长将在微观世界中进行评估 受到确定的沉积物扰动（并在未受干扰的 和杀死的对照组），根据时间和空间变化 在细菌丰度、生物体积和分裂频率方面 细胞，通过落射荧光显微镜测定。 胞外酶 使用荧光底物类似物测量活性。 这两个过程将在选定的实验中进行交叉检查 使用放射性同位素方法。 一个主要目标是记录 静态沉积物的物理扰动程度 影响随后的细菌参数（反过来， 影响食物资源以获得更高的营养水平），最终 为预测输沙效应奠定基础 自然海洋沉积物中的事件。

Factors believed to stimulate bacteria in marine sediments, and therefore to enhance their role(s) in benthic communities and nutrient cycles, include increased nutrient supply, grazing pressure, and physical transport events. Dr. Deming's research will determine the effects of sediment transport on two key bacterial parameters, growth and exoenzyme production, in initially simplistic and progressively more complex simulations: static (single core), gradostatic (multiple cores linked in series across nutrient gradients), and hydrodynamic (flume) microcosms. Growth will be assessed in microcosms subjected to a defined sediment disturbance (and in undisturbed and killed controls), according to temporal and spatial shifts in bacterial abundance, biovolume, and frequency of dividing cells, determined by epifluorenscence microscopy. Exoenzyme activity will be measured using fluorescent substrate analogs. Both processes will be cross-checked in selected experiments using radiosotopic approaches. A major goal is to document the degree to which physical disturbance of quiescent sediments influences subsequent bacterial parameters (which, in turn, influence food resources for higher trophic levels), ultimately building a basis for predicting effects of sediment transport events in natural marine sediments.