报告题目：Patterns of microzooplankton grazing in contrasting biogeochemical provinces of the temperate and sub-tropical Atlantic Ocean

　　报 告 人：Richard Rivkin

　　工作单位：Memorial University of Newfoundland

　　报告时间：2015年6月11日（星期四）10:00-11:00

　　报告地点：行政楼214报告厅

　　报告摘要:

　　Microzooplankton are important in controlling the abundance, biomass and diversity of bacteria, phytoplankton, they recycle and remineralize inorganic and inorganic nutrients and account for a large fraction of upper ocean respiration. The rates of growth and microzooplankton-mediated mortality of bacteria and phytoplankton were quantified during contrasting seasons in several distinct biogeochemical provinces in the temperate and sub-tropical Atlantic, representing a wide range of temperature and nutrient conditions and food web structures. The grazing impact on microbial prey ranged from undetectable to > 1/d, and rates of growth mortality and grazing preferences differed between and within different biogeochemical provinces. Bacteria generally dominated biomass throughout region, and bacterivory accounted for 50 to 80% of the ingested carbon. Rates of bacterial growth and mortality were in balance in subtropical/tropical regions, but were uncoupled at higher latitudes. Bacteria and phytoplankton appeared to be preferentially ingested in different latitudinal regions. Thus, microzooplankton are crucial in controlling the structure of the microbial community, in determining the fate of microbial production in the surface layer and the biogeochemical cycling of carbon and mineral nutrients.

　　报告人简介：

　　Rivkin教授是海洋微型生物生态领域的国际著名专家，目前就职于加拿大纽芬兰纪念大学海洋科学学部，主要研究方向包括海洋微食物网动态及其对海洋生物地球化学循环和海洋气候相互作用的影响。在1991年就职于纪念大学之前，Rivkin教授曾任马里兰大学（1983-1991）环境重点实验室和约翰霍普金斯大学（1978-1983）的研究员。在美国期间，Rivkin教授主要研究温带、热带海洋和南极海域浮游植物的生理生态和微食物网过程。就职加拿大后，Rivkin教授继续在微食物网的生理生态学各个方面从事研究，并利用模型评估他们在全球尺度上调控海洋生物地球化学循环的作用。

　　Rivkin教授目前为美国地球物理学会、美国海洋与湖沼学会、加拿大微生物学会和欧洲地球科学学会的会士。目前已发表学术论文100余篇，其中11篇发表在Nature、Science等顶级学术刊物上。主持美国海洋与湖沼学会年会、美国地球物理学会年会、欧洲物理学会年会等本领域国际顶级学术会议20余次。