Island mass effects on planktonic communities in the open ocean

这项研究正在使用现有的数据来描述太平洋20个地点的岛屿质量效应(IME)。当岛屿和环礁改变大气和海洋环流，导致表层水域局部富含营养物质时，就会产生岛屿质量效应。当地化肥反过来促进浮游植物水华和高浮游生物生物量，这些浮游生物可以平流到周围的开阔海域，并加强低营养物质可获得性和低浮游生物生物量的地区。岛屿质量效应(IME)被认为足够重要，足以影响区域渔业和生物地球化学过程，但我们目前对这一现象的大部分了解来自卫星遥感观测，即作为浮游植物生物量的替代指标的叶绿素浓度升高。该项目需要对从岛屿的泻湖和沿海水域到公海的浮游植物和浮游动物的生物量和组成沿环境梯度的变化进行系统的、流域范围的评估。这项研究利用了在塔拉太平洋探险期间(2016-2018年)收集的一个大型数据集，结果提供了有关海洋生态对IME的反应的新信息，以及改善世界海洋欠采样区域生态系统模型所需的浮游生物清单。除了支持研究生和本科生外，该项目还为早期职业科学家提供了关于收集和处理船舶在航数据的最佳做法的培训讲习班。太平洋少营养环流中的岛屿改变海洋和大气循环，并提供肥料来源，以促进当地浮游植物的繁殖。这种所谓的岛屿质量效应(IME)是太平洋上普遍存在的一种现象，众所周知，太平洋广大地区受到宏观和微观营养物质可获得性的限制，但人们主要通过卫星遥感观测到的叶绿素浓度升高来理解这种现象。除了对叶绿素的遥感外，只对少数岛屿的浮游生物群落组成和结构的同步变化进行了研究，限制了我们对IME生物反应的了解。在这个项目中，研究人员正在通过评估浮游植物群落组成、中浮游动物生物量和浮游生物多样性来检查20个地点的IME。调查人员正在利用在塔拉太平洋探险期间(2016-2018年)收集的全面数据集，其中包括：环境测量(温度、盐度、营养物质和痕量金属)、浮游生物样本(流式细胞仪、浮游生物成像、色素和基因组学)、高分辨率光学特性测量(生物地球化学替代物)、卫星遥感数据(叶绿素、温度、海面高度)和来自海洋环流模型(墨卡托海洋)的洋流。这一裁决反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This study is using existing data to characterize the Island Mass Effect (IME) at 20 locations across the Pacific Ocean. The Island Mass Effect occurs when islands and atolls alter atmospheric and oceanic circulation, resulting in local enrichment of surface waters with nutrients. Local fertilization, in turn, promotes phytoplankton blooms and high plankton biomass that can be advected into the surrounding open ocean and enhance regions of low nutrient availability and low plankton biomass. The Island Mass Effect (IME) is thought to be sufficiently important to affect regional fisheries and biogeochemical processes, but most of our current understanding of this phenomenon comes from satellite remote sensing observations of elevated chlorophyll concentrations that serve as a proxy for phytoplankton biomass. This project entails a systematic, basin-scale evaluation of changes in phytoplankton and zooplankton biomass and composition along environmental gradients from the lagoons and coastal water of islands into the open ocean. The study is making use of a large dataset collected during the TARA Pacific expedition (2016-2018), and results are providing new information about marine ecological responses to IME and the plankton inventories needed to improve ecosystem models for under sampled regions of the world’s oceans. In addition to supporting graduate and undergraduate students, this project offers a training workshop for early career scientists on best practices for the collection and processing of ship-based underway data.Islands in the oligotrophic gyres of the Pacific Oceans alter oceanic and atmospheric circulation and provide sources of fertilization to promote local phytoplankton blooms. This so-called Island Mass Effect (IME) is a ubiquitous phenomenon in the Pacific Ocean where vast areas are known to be limited by the availability of macro- and micro-nutrients, yet it is mostly understood from satellite remote sensing observations of elevated chlorophyll concentrations. Beyond remote sensing of chlorophyll, concurrent changes in plankton community composition and structure have been examined for only a small number of islands, limiting our understanding of the biological responses to IME. In this project, the investigators are examining the IME at 20 locations by evaluating phytoplankton community composition, mesozooplankton biomass, and plankton diversity. The investigators are making use of a comprehensive data set collected during the TARA Pacific expedition (2016-2018) that includes: environmental measurements (temperature, salinity, nutrients and trace metals), plankton samples (flow cytometry, plankton imaging, pigments, and genomics), high resolution measurements of optical properties from which biogeochemical proxies are derived, satellite remote sensing data (chlorophyll, temperature, sea surface height), and currents from an ocean circulation model (Mercator Oceans).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.