Partitioning of C, N and P between particulate and dissolved phases during growth of phytoplankton at different pH.

不同pH下浮游植物生长过程中C、N和P在颗粒相和溶解相之间的分配。

• 批准号: NE/F003455/1
• 负责人: Kevin Flynn
• 金额: $ 37.39万
• 依托单位: Swansea University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FF003455%2F1
• 关键词: Partitioning; between; particulate; dissolved; phases

Marine phytoplankton play a central role in the cycling of biologically important elements, such as carbon (C), nitrogen (N) and phosphorous (P) between the atmosphere, ocean and marine sediments. Over short periods (weeks) phytoplankton can proliferate, forming vast blooms of new cells that contribute to the Particulate Organic Matter (POM) in the surface ocean. In so doing, they take up nutrients (N and P) and carbon dioxide (CO2) from seawater. This CO2 is replaced by atmospheric CO2 that dissolves in the surface ocean and restores the long-term ocean-atmosphere balance. During a bloom, some cells are consumed by grazers, supporting marine food webs, while others die or stick together and sink. Material reaching the marine sediment contributes to the 'biological carbon pump' which is capable of burying atmospheric CO2 and other nutrients over geological time scales. However, these are not the only fates for assimilated nutrients. During the growth of phytoplankton, organic molecules are released from the cells to the surrounding seawater. These organics (dissolved organic matter / DOM) are used by bacteria which degrade them, regenerating nutrients and releasing CO2 and other climatically active (or greenhouse) gases to the atmosphere. Consequently, the fate of assimilated nutrients, as either POM or DOM, has important implications for the productivity of marine food webs, for CO2 that may be removed from the atmosphere and for the release of greenhouse gases to the atmosphere from the surface ocean. During blooms, the partitioning of nutrients by phytoplankton between POM and DOM changes substantially although our quantitative understanding of this process is limited. In fact, there are no robust, quantitative data available that describe this partitioning in relation to the health of the phytoplankton cells. Without these data we are unable to develop and refine mathematical models that allow us to investigate the implications for marine ecosystems and for global climate change. This project will address this important shortfall in our understanding. An important factor accompanying the consumption of nutrients during phytoplankton blooms is the increase in seawater pH, from 8.2 to greater than 8.5. Ultimately phytoplankton cease to function if the pH exceeds their tolerance, with implications for species succession during bloom propagation. This aspect is usually ignored in models. We have no quantitative or rigorous data available which describes the combination of nutrient limitation and elevated pH, which is likely to effect nutrient partitioning during the acclimation process, and hence the productivity and biogeochemical impact of the bloom. This project will specifically address the impact of changes in pH upon the growth dynamics of marine phytoplankton. In contrast to periods of elevated seawater pH during blooms, evidence points to an acidification of the oceans (pH falls) during the coming decades as anthropogenic CO2 derived from human activity dissolves in the surface ocean. The impact upon the growth of phytoplankton, nutrient partitioning, and their capacity to acclimate to a relatively acidic environment is completely unknown. The implications for the marine environment and the services that it provides warrants urgent investigation. This project, conducted jointly between Swansea University and Plymouth Marine Laboratory, will see cultures of representative phytoplankton subjected to different conditions (nutrient availability, pH) representing current day and future (acidified oceanic) situations. Data describing changes in growth and activity of the organisms will support the construction and testing of mathematical models. The results will thence be incorporated into ecosystem models that will examine the implications for marine productivity and biogeochemistry of the improved description of phytoplanktonic activity, and of ocean acidification for the UK shelf seas.

海洋浮游植物在大气、海洋和海洋沉积物之间的碳(C)、氮(N)和磷(P)等重要生物元素的循环中发挥着核心作用。在短时间内（几周），浮游植物可以增殖，形成大量的新细胞，为海洋表面的颗粒有机物质（POM）做出贡献。在这样做的过程中，它们从海水中吸收养分（氮和磷）和二氧化碳（CO2）。这些二氧化碳被溶解在海洋表面的大气二氧化碳所取代，从而恢复海洋与大气的长期平衡。在水华期间，一些细胞被食草动物消耗，支撑着海洋食物网，而其他细胞则死亡或粘在一起沉没。到达海洋沉积物的物质有助于“生物碳泵”，它能够在地质时间尺度上掩埋大气中的二氧化碳和其他营养物质。然而，这些并不是被同化的营养物质的唯一归宿。在浮游植物生长的过程中，有机分子从细胞释放到周围的海水中。这些有机物（溶解的有机物/ DOM）被细菌利用，降解它们，再生营养物质，并向大气释放二氧化碳和其他气候活跃（或温室）气体。因此，被同化的营养物质的命运，无论是作为聚甲醛还是多溴化DOM，对海洋食物网的生产力、可能从大气中去除的二氧化碳以及从海洋表面向大气释放的温室气体都有重要影响。在水华期间，浮游植物在POM和DOM之间的营养分配发生了实质性的变化，尽管我们对这一过程的定量理解有限。事实上，目前还没有可靠的定量数据来描述这种分配与浮游植物细胞健康的关系。没有这些数据，我们就无法开发和完善数学模型，使我们能够调查海洋生态系统和全球气候变化的影响。这个项目将解决我们认识上的这一重要不足。在浮游植物繁殖期间伴随养分消耗的一个重要因素是海水pH值从8.2增加到大于8.5。最终，如果pH值超过浮游植物的耐受性，浮游植物就会停止工作，这对藻华繁殖过程中的物种演替有影响。这方面通常在模型中被忽略。我们没有定量或严格的数据来描述营养限制和pH升高的组合，这可能会影响驯化过程中的营养分配，从而影响水华的生产力和生物地球化学影响。本项目将专门研究pH值变化对海洋浮游植物生长动态的影响。与藻华期间海水pH值升高的时期相反，有证据表明，由于人类活动产生的人为二氧化碳溶解在海洋表面，未来几十年海洋将酸化（pH值下降）。对浮游植物生长、营养分配以及它们适应相对酸性环境的能力的影响是完全未知的。对海洋环境的影响及其提供的服务值得紧急调查。这个项目是由斯旺西大学和普利茅斯海洋实验室联合进行的，将看到有代表性的浮游植物在不同条件下的培养（营养可用性，pH值），代表了现在和未来（酸化海洋）的情况。描述生物生长和活动变化的数据将支持数学模型的构建和测试。研究结果将被纳入生态系统模型，以检验改进后的浮游植物活动描述和英国大陆架海洋酸化对海洋生产力和生物地球化学的影响。

项目成果

In silico optimization for production of biomass and biofuel feedstocks from microalgae.

利用微藻生产生物质和生物燃料原料的计算机优化。

• DOI: 10.1007/s10811-014-0342-2
• 发表时间: 2015
• 期刊: Journal of applied phycology
• 影响因子: 3.3
• 作者: Kenny P

Ocean acidification with (de)eutrophication will alter future phytoplankton growth and succession.

• DOI: 10.1098/rspb.2014.2604
• 发表时间: 2015-04-07
• 期刊: Proceedings. Biological sciences
• 作者: Flynn KJ;Clark DR;Mitra A;Fabian H;Hansen PJ;Glibert PM;Wheeler GL;Stoecker DK;Blackford JC;Brownlee C
• 通讯作者: Brownlee C

Changes in pH at the exterior surface of plankton with ocean acidification

• DOI: 10.1038/nclimate1489
• 发表时间: 2012-07-01
• 期刊: NATURE CLIMATE CHANGE
• 影响因子: 30.7
• 作者: Flynn, Kevin J.;Blackford, Jerry C.;Wheeler, Glen L.
• 通讯作者: Wheeler, Glen L.

Minimising losses to predation during microalgae cultivation.

• DOI: 10.1007/s10811-017-1112-8
• 发表时间: 2017
• 期刊: Journal of applied phycology
• 影响因子: 3.3
• 作者: Flynn KJ;Kenny P;Mitra A
• 通讯作者: Mitra A

Ocean Acidification Affects the Phyto-Zoo Plankton Trophic Transfer Efficiency.

• DOI: 10.1371/journal.pone.0151739
• 发表时间: 2016
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Cripps G;Flynn KJ;Lindeque PK
• 通讯作者: Lindeque PK