Collaborative Research: Protistan Abundance, Diversity and Activity in the Deep-Sea and at Hydrothermal Vents

合作研究：深海和热液喷口的原生生物丰度、多样性和活动

• 批准号: 0550829
• 负责人: David Caron
• 金额: $ 40万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0550829&HistoricalAwards=false
• 关键词: Collaborative; Research; Protistan; Abundance; Diversity

Protistan assemblages are essential components of food webs in the vast majority of aquatic ecosystems that have been examined to date. Despite the pivotal roles that these organisms play in carbon fixation, energy utilization and elemental cycling in marine ecosystems, little information exists on the presence, abundance and activities of these species in the deep ocean in general, and in particular at and around hydrothermal vents. The latter environments should be particularly conducive to the growth of phagotrophic protists in the deep ocean because biomass is greatly elevated at these sites and organic carbon availability in these regions is largely mediated by archaeal and bacterial assemblages. This research project will address fundamental questions regarding the species diversity, abundances of specific taxa, and trophic activities of protists within the deep ocean including hydrothermal vent areas. Specifically, the PIs will determine whether deep-sea communities harbor endemic assemblages of protists, establish the identity of the protists associated with these environments that are trophically active, and document the protistan taxa that dominate these assemblages in situ. They will examine the diversity of the protistan assemblages in the deep-sea away from the vents and in the overlying water column, and in microenvironments in and around hydrothermal vents and associated with dominant macrofauna of vents. Traditional (microscopy) and molecular biological (18S rDNA) approaches will be used to characterize abundance and diversity. Observations of the ingestion of fluorescently labeled prey will be used to establish trophically active protists in situ. They will also employ 18S rDNA clone libraries, cultures and microscopy-based observations to target specific taxa for the application of fluorescent in situ hybridization (FISH) to link morphological identity to commonly occurring (and trophically active) phylotypes. A culture collection of deep-sea protists will be established to further characterize protistan diversity and also to provide specimens for baseline physiological measurements in the laboratory. Growth rates will be examined in the laboratory using cultured protists grown under temperatures, pressures and water chemistries representative of deep-sea environments. Hydrothermal vent research is an excellent vehicle for incorporation into education at all levels ranging from elementary through graduate level. The information resulting from this research will be incorporated into undergraduate and graduate courses by the PIs, and will be featured on the Caron Lab Homepage. The PIs and the postdoctoral investigator supported by this project will participate directly in an ongoing teacher education program (Centers for Ocean Science Education Excellence; COSEE-West) that will reach middle and high school students, most of whom are Hispanic, African-American or other ethnic minorities and most of whom are economically disadvantaged. This will be accomplished through existing teacher enhancement and student enrichment activities that will incorporate this research into a learning experience that will enhance student awareness of environmental science, microbiology and the natural world. This work will be the center feature for the internationally acclaimed Extreme 2000 outreach program for secondary schools which has, over the last 5 years, directly engaged over 180,000 students throughout the US and 9 foreign countries. Contributions from this project will educate the public at every level about the deepsea, and the importance of microbes in forming and maintaining the biosphere.

在迄今已研究的绝大多数水生生态系统中，原始组合是食物网的重要组成部分。尽管这些生物体在碳固定中发挥了关键作用，在海洋生态系统中的能量利用和元素循环中，但对这些物种在深海中的存在，丰富性和活动的总体上很少，尤其是在深海中，尤其是在水热通风孔中。后一种环境应特别有利于深海中吞噬生物的生长，因为在这些地点生物量大大升高，并且这些地区的有机碳的可用性在很大程度上是由古细菌和细菌组合介导的。该研究项目将解决有关物种多样性，特定分类单元的丰富性以及深海中生物的营养活动的基本问题，包括水热区域。具体而言，PIS将确定深海社区是否具有生物的地方性大会，建立与这些营养活跃的环境相关的生物的身份，并记录在原位占主导地位的protistan群体。他们将检查深海中的Protistan组合的多样性，远离通风孔和上覆的水柱，以及水热通风孔和周围的微环境，并与通风孔的主要大型莫克罗纳（Macrofauna）有关。传统（显微镜）和分子生物学（18S rDNA）方法将用于表征丰度和多样性。摄入荧光标记的猎物的观察将用于原位建立营养活跃的生物。他们还将采用18S rDNA克隆文库，培养物和基于显微镜的观察结果，以针对特定的分类单元，以应用原位杂交（FISH），以将形态学身份与常见（和营养活性）的系统型联系起来。将建立深海生生物的培养物收集，以进一步表征原生动物的多样性，并为实验室中基线生理测量的标本提供标本。将使用代表深海环境的温度，压力和水化学物质生长的培养生物在实验室中检查增长率。 Hydrothermal VENT Research是从基础到研究生层面的各个级别中纳入教育的绝佳工具。这项研究产生的信息将由PIS纳入本科和研究生课程，并将在Caron Lab Homepage上进行。该项目支持的PIS和博士后调查员将直接参加正在进行的教师教育计划（海洋科学教育中心； Cosee-West中心），该计划将覆盖中学生和高中生，其中大多数是西班牙裔，非裔美国人或其他少数民族，其中大多数是经济上的不利因素。这将通过现有的教师增强和学生丰富的活动来实现，这些活动将将这项研究纳入学习经验，从而提高学生对环境科学，微生物学和自然世界的认识。这项工作将是国际备受赞誉的2000年中学极限外展计划的中心功能，在过去的5年中，在美国和9个国外直接吸引了18万名学生。该项目的贡献将在各个层面教育公众关于深海的教育，以及微生物在形成和维持生物圈中的重要性。