Assessing the link between zooplankton, microbes and the global biogeochemical cycles

评估浮游动物、微生物和全球生物地球化学循环之间的联系

• 批准号: 445462226
• 负责人: Dr. Daniele De Corte, Ph.D.
• 金额: --
• 依托单位: Institut für Chemie und Biologie des Meeres (ICBM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/445462226?language=en
• 关键词: Assessing; link; between; zooplankton; microbes

Crustacean zooplankton are one of most abundant macro organisms in the ocean. They are important constituents of the marine trophic food webs, channeling the newly synthesized organic matter from phytoplankton towards higher trophic levels. However, they also interact with heterotrophic microbes, providing microenvironments rich in organic matter and nutrients, low oxygen concentration and pH. Consequently, they facilitate the proliferation of specific microbial groups and promote metabolic processes that are generally underrepresented in open water of marine pelagic ecosystems, such as fermentation and metanogenesis. Therefore, zooplankton and the zooplankton-associated microbiome play an important role in the organic matter and nutrients re-cycling. However, little is known about rates and fluxes of the biogeochemical processes mediated by zooplankton and their microbiome in marine pelagic waters, where zooplankton usually reside. The proposal aims to link two aspects of the marine food web usually independently studied, zooplankton ecology and microbial oceanography. The proposed study will investigate the influence of zooplankton activity on the composition and activity of prokaryotic communities in coastal waters. We propose to use a multidisciplinary approach that combines analytical chemical and microbiological techniques to advance our understanding on the interaction between zooplankton and the main drivers of the biogeochemical cycles, the prokaryotes. Therefore, the expected results from this study should also contribute to better understand the overall impact of zooplankton and their associated microbiome on the global biogeochemical cycles. The dominant copepod groups from the southern North Sea will be collected and the community composition of the copepod-associated microbial community will be determined. Special focus will be devoted in three of the main copepod species from the coastal North Sea, i.e., Acartia tonsa, Pseudocalanus and Calanus helgolandicus. The response of the free living microbial community composition and activity to zooplankton grazing on phytoplankton will be assessed during incubation experiments, and compared to the microbial community from the ambient waters. Single cell activity measurements, metagenomics and metatranscriptomics will be used to assess the microbial groups and metabolic pathways stimulated by zooplankton grazing in comparison to ambient water microbes not exposed to zooplankton grazing by-products. Additionally, the incubation experiments will be used to assess the potential role of zooplankton grazing in nutrient re-cycling, e.g., iron, and methane release in oxygenated waters.

甲壳类浮游动物是海洋中数量最多的大型生物之一。它们是海洋营养食物网的重要组成部分，将浮游植物中新合成的有机物质引导到更高的营养水平。然而，它们也与异养微生物相互作用，提供富含有机物和营养物质、低氧浓度和ph的微环境。因此，它们促进了特定微生物群的增殖，并促进了在海洋远洋生态系统开放水域中通常未被充分代表的代谢过程，如发酵和新陈代谢。因此，浮游动物和与浮游动物相关的微生物群在有机物和营养物质的再循环中起着重要作用。然而，在浮游动物通常居住的海洋中上层水域中，浮游动物及其微生物群介导的生物地球化学过程的速率和通量知之甚少。该提案旨在将通常独立研究的海洋食物网的两个方面——浮游动物生态学和海洋微生物学——联系起来。本研究将探讨浮游动物活动对沿海水域原核生物群落组成和活性的影响。我们建议采用多学科的方法，结合分析化学和微生物技术，以提高我们对浮游动物与生物地球化学循环的主要驱动力——原核生物之间相互作用的理解。因此，本研究的预期结果也将有助于更好地了解浮游动物及其相关微生物组对全球生物地球化学循环的总体影响。收集北海南部桡足类优势类群，确定桡足类相关微生物群落组成。特别关注北海沿岸的三种主要桡足类，即Acartia tonsa， pseudoalanus和Calanus helgolandicus。在培养实验期间，将评估浮游动物放牧浮游植物对自由生活微生物群落组成和活性的响应，并与环境水域的微生物群落进行比较。单细胞活性测量、宏基因组学和超转录组学将用于评估浮游动物放牧所刺激的微生物群和代谢途径，并将其与未暴露于浮游动物放牧副产品的环境水中微生物进行比较。此外，孵化实验将用于评估浮游动物放牧在营养物质再循环中的潜在作用，例如在含氧水域中释放铁和甲烷。