Collaborative Research: Controls on climate-active gases by Amundsen Sea ice biota

摘要目前有令人信服的证据证实，由于人类活动，极地正在迅速发生变化。海冰范围和厚度的变化将对高纬度地区的生产力、食物网和碳通量产生深远影响，因为海冰生物群是生态系统生物物质的重要来源。虽然海冰通常被认为是海洋和大气之间气体交换的屏障，但它更有可能是二氧化碳和消耗臭氧的有机卤素等气候活性气体的来源或汇，部分原因是海冰基质中嵌入的微生物的活动。该项目汇集了经验丰富的美国和瑞典研究人员，以研究海冰生物群对南大洋太平洋部分主要气候活性气体产生和降解的控制。我们假设：1)海冰环境的物理性质决定了海冰生物群的群落结构和活动；2)冰藻的生产力、生物量、生理状态和物种组成将决定特定类别有机碳的产生，包括有机卤素；3)冰内的异养共代谢将在一定程度上分解这些化合物，这取决于微生物群落结构和生产力；4)海冰对大气的CO2和有机卤素通量将呈负相关。该项目将在美国和瑞典科学家之间建立密切的科学合作，并培训年轻科学家，包括代表性不足的群体的成员。结果的传播将包括科学文献和公共宣传场所，包括与PolarTrec老师的互动。

AbstractConvincing evidence now confirms that polar regions are changing rapidly in response to human activities. Changes in sea ice extent and thickness will have profound implications for productivity, food webs and carbon fluxes at high latitudes, since sea ice biota are a significant source of biogenic matter for the ecosystem. While sea ice is often thought to be a barrier to gas exchange between the ocean and the atmosphere, it more likely functions as a source or sink for climate-active gases such as carbon dioxide and ozone-depleting organohalogens, due in part to activities of microbes embedded in the sea ice matrix. This project brings together experienced US and Swedish investigators to examine the controls by sea-ice biota on the production and degradation of key climate-active gases in the Pacific sector of the Southern Ocean. We hypothesize that 1) the physical properties of the sea-ice environment will determine the community structure and activities of the sea ice biota; 2) the productivity, biomass, physiological state and species composition of ice algae will determine the production of specific classes of organic carbon, including organohalogens; 3) heterotrophic co-metabolism within the ice will break down these compounds to some extent, depending on the microbial community structure and productivity, and 4) the sea ice to atmosphere fluxes of CO2 and organohalogens will be inversely related. This project will build close scientific collaborations between US and Swedish researchers and also train young scientists, including members of underrepresented groups. Dissemination of results will include the scientific literature, and public outreach venues including interactions with a PolarTrec teacher.