SGER: Construction and Deployment of a High Pressure Chemostat System for the Culture of Deep Sea Bacteria and Nanoplankton Protists

大约一半的洋底被水深超过4000米的水覆盖，使深海成为地球上最大的栖息地。 海洋内部的庞大规模使其成为全球碳循环的重要组成部分，尽管深海中的生命密度比海洋表面低得多。 有机养分几乎完全是通过颗粒下沉和溶解物质从地表平流而来的。 细菌对生物可利用有机碳的降解和原生生物对细菌的摄食是深海的主要生物过程。 这两组生物似乎有助于生产的耐火有机材料所反映的高14C年龄的溶解有机物。 由于无法进入深海生态系统，对这些过程的了解受到限制。 深海研究中最具挑战性的问题之一是，样本在回收时暴露于巨大的压力和温度梯度。 为了解决这个问题，Bochandsky博士将建造一个装置，在从深海取回样本的同时保持原位压力和温度。 这些样品将用于测量深海生物的生长、细菌摄食和溶解有机物的产生。 关于原生生物特有性的基本问题也将得到解决。 该项目是与荷兰皇家海洋研究所合作进行的。 更广泛的影响包括技术进步，国际合作和对全球碳循环的见解的贡献。

Approximately half of the area of the ocean floor is covered with water deeper than 4000 m making the deep sea the largest habitat on earth. The sheer size of the ocean interior makes it an important component of the global carbon cycle even though life occurs at much lower densities in the deep sea than at the ocean's surface. Organic nutrients arrive almost exclusively through the sinking of particles and the advection of dissolved matter from the surface. The degradation of bioavailable organic carbon by bacteria and the grazing on bacteria by protists are dominant biological processes in the deep ocean. Both groups of organisms seem to contribute to the production of refractory organic material reflected by the high 14C age of dissolved organic matter. Understanding these processes is limited by the inaccessibility of the deep sea ecosystem. One of the most challenging issues in deep sea research is the exposure of samples to large pressure and temperature gradients as they are retrieved. In an effort to eliminate this problem, Dr. Bochandsky will build a device to maintain in situ pressure and temperature while retrieving samples from the deep sea. The samples will allow measurements of growth, bacterial grazing and production of dissolved organic matter of deep sea organisms. Fundamental questions regarding the endemism in protists will also be addressed. The project is being done in collaboration with the Royal Netherlands Institute of Sea Research. Broader impacts include technology advancement, international collaboration and contributions to insights into the global carbon cycle.