Island mass effects on planktonic communities in the open ocean

这项研究使用现有数据来描述太平洋上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时，就会发生岛屿质量效应，导致局部地表水的营养物质富集。当地的施肥反过来又促进浮游植物大量繁殖和高浮游生物生物量，这些浮游生物可以平流到周围的公海，并加强低营养可利用性和低浮游生物生物量的区域。岛屿质量效应（IME）被认为是影响区域渔业和生物地球化学过程的重要因素，但我们目前对这一现象的大部分理解来自卫星遥感观测的叶绿素浓度升高，叶绿素浓度作为浮游植物生物量的代表。该项目需要对浮游植物和浮游动物生物量和组成的变化进行系统的、盆地尺度的评估，沿着从泻湖和岛屿沿海水域到公海的环境梯度进行评估。该研究利用了TARA太平洋考察（2016-2018）期间收集的大型数据集，结果提供了关于海洋生态对IME的反应的新信息，以及改善世界海洋采样不足地区生态系统模型所需的浮游生物清单。除了为研究生和本科生提供支持外，该项目还为早期职业科学家提供了一个关于收集和处理船舶航行数据的最佳实践的培训讲习班。太平洋少营养环流中的岛屿改变了海洋和大气环流，并提供了施肥来源，促进了当地浮游植物的大量繁殖。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，太平洋上的大片地区受到宏观和微观营养物质的限制，但它主要是通过对叶绿素浓度升高的卫星遥感观测来了解的。除了叶绿素遥感之外，浮游生物群落组成和结构的同步变化仅在少数岛屿上进行了研究，这限制了我们对IME生物响应的理解。在本项目中，研究人员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，对20个地点的IME进行了研究。调查人员正在利用TARA太平洋考察（2016-2018）期间收集的综合数据集，其中包括：环境测量（温度、盐度、营养物质和微量金属）、浮游生物样本（流式细胞术、浮游生物成像、色素和基因组学）、高分辨率光学特性测量（生物地球化学代用物）、卫星遥感数据（叶绿素、温度、海面高度）以及海洋环流模型（墨卡托海洋）的洋流。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.