Application of a Cooled CCD Imaging System to the Study of Microorganisms and Non-Living Particles in the Picoplankton Size Range

海洋浮游生物系统中的亚微米颗粒可能发挥作用 在系统的基础化学和生物学中的重要作用， 在人口和食物网动态以及生物地球化学方面 骑自行车 微微型浮游生物大小范围内的颗粒包括 微生物、病毒和非生命碎屑颗粒。 的 丰度，大小光谱和荧光性质，这些不同的 可以使用图像分析的落射荧光来测量颗粒 显微镜 在“长周期开发”项目的资助下， 美国联合全球海洋通量研究计划”，一个敏感的， 精确的图像分析系统，已经开发，基于一个 冷却的CCD相机，以自动化这些测量的自然 样品 这个奖项是对过去的一种更新， 该奖项旨在提升系统的空间分辨率， 增加这些尺寸测量的精度 粒子 该仪器将用于 小颗粒的总体表征 丰度、大小光谱和荧光染料染色。 系统 将使用已知的病毒浓缩物进行校准，以确定 它们可以根据大小与小细菌区分开来 和荧光特性。 该仪器将用于 在JGOFS百慕大时间表征粒子群 系列站和当地河口沃茨。 样品也将 通过电子显微镜以及碳和 氮的组成，特别是一些大小分级 样品 这种多样的测量方法应该会导致一个更好的 了解这些粒子的性质及其 在海洋生物地球化学循环中的潜在作用。

Sub-Micrometer particles in marine plankton systems may play important roles in the basic chemistry and biology of the system, in population and food web dynamics and in biogeochemical cycling. Particles in the picoplankton size range include living microorganisms, viruses and non-living detrital particles. The abundance, size spectra and fluorescent nature of these various particles can be measured using image analyzed epifluorescence microscopy. With funding from the "Long-Lead Time Development Program" of the US Joint Global Ocean Flux Study, a sensitive, accurate image analysis system, has been developed, based on a cooled CCD camera, to automate these measurements of natural samples. This award which constitutes a renewal of the past award is to upgrade the spatial resolution of the system to increase the precision of the size measurements of these particles. The instrument will than be used for the characterization of small particles in terms of population abundances, size spectra, and fluorochrome staining. The system will be calibrated using known virus concentrates to determine if they can be distinguished from small bacteria based on their size and fluorescence characteristics. The instrument will be used to characterize particle populations at the JGOFS Bermuda Time Series station and in local estuarine waters. Samples will also be analyzed by electron microscopy as well as for carbon and nitrogen composition, particularly some of the size-fractionated samples. This variety of measurements should lead to a better understanding of the nature of these particles and their potential roles in marine biogeochemical cycles.