Doctoral Dissertation Research: The role of early life-stage bottlenecks in Arctic benthic fjord communities

鉴于北极大部分地区地处偏远，该地区许多地方对基本生态系统功能仍然知之甚少。例如，我们对海底无脊椎动物的早期生命阶段-胚胎、幼体和幼鱼-知之甚少，这些阶段对海洋生态系统的健康至关重要，但特别容易受到环境压力的影响。本论文的研究将侧重于记录海底无脊椎动物的生命周期，以了解海底群落如何受到气候变暖的影响。虽然目前的研究表明，北极冰川峡湾的海底群落随着空间和深度的变化而变化，但目前尚不清楚这些动物在生命早期阶段的扩散和死亡如何塑造这些梯度。这项研究将确定年轻生物何时何地定居在海底，并描述整个冰川峡湾的死亡率。该研究将展示环境压力因素，如气温升高或入侵物种的引入，如何影响动物的生命周期并推动其社区的梯度。本研究将解决三个关键问题，在Kongsfjorden，斯瓦尔巴群岛：（1）底栖无脊椎动物幼虫的分布是如何在时间和空间尺度上变化的？(2)如何解决（例如，速率和物种组成）在冰川主导的峡湾中变化？(3)在北极硬底系统中，定居后死亡率的模式是什么？将在Kongsfjorden部署一个新发明的摄像系统，以连续和自主地观察底栖无脊椎动物的沉降和沉降后的死亡率。将使用浮游生物网收集幼虫样本，并使用综合形态学和分子分类学进行鉴定，以了解当地物种和从低纬度向北迁移的物种的扩散模式。此外，综合分类学将产生成对的摄影和遗传数据集，以帮助对幼虫进行形态学鉴定，并提供给其他研究人员。这些创新的方法将允许对受冰川影响的极地峡湾的气候影响进行精确的预测。该项目还将通过制作供K-12教育工作者和学生广泛使用的交互式数据和材料来促进北极教育。该奖项反映了NSF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。

Given the remoteness of much of the Arctic, fundamental ecosystem functions are still little understood in many parts of the region. For example, we know little about the early life stages of seafloor invertebrates - embryos, larvae, and juveniles – which are vital for the health of marine ecosystems but are especially vulnerable to environmental stressors. This dissertation research will focus on documenting the life cycles of seafloor invertebrate animals to understand how seafloor communities are impacted by a warming climate. While current research has shown that seafloor community changes over space and depth in Arctic glacial fjords, it is currently unknown how dispersal and mortality in the early life stages of these animals shape these gradients. This research will identify when and where young organisms settle to the seafloor and characterize mortality rates throughout a glacial fjord. The research will demonstrate how environmental stressors, such as warming temperatures or the introduction of invasive species, can impact animals’ life cycles and drive the gradients in their communities. This study will address three critical questions in Kongsfjorden, Svalbard: (1) How do the distributions of benthic invertebrate larvae vary across temporal and spatial scales? (2) How does settlement (e.g., rate and species composition) vary across a glacially dominated fjord? (3) What are the patterns of post-settlement mortality in an Arctic hard bottom system? A newly-invented camera system will be deployed in Kongsfjorden to continuously and autonomously observe settlement and post-settlement mortality in benthic invertebrates for the first time. Larval samples will be collected using plankton nets and identified using integrative morphological and molecular taxonomy to understand dispersal patterns for both local species and those moving north from lower latitudes. Additionally, the integrative taxonomy will yield a paired photographic and genetic dataset to aid in morphological identification of larvae that will be made available to other researchers. These innovative approaches will allow for refined predictions of climate impacts in glacially influenced polar fjords. This project will also promote Arctic education by producing interactive data and materials for use by a wide range of K-12 educators and students.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.