Coralline algae as recorders of environmental change

珊瑚藻作为环境变化的记录者

• 批准号: 341876-2012
• 负责人: Halfar, Jochen
• 金额: $ 3.35万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=527497
• 关键词: Coralline; algae; recorders; environmental; change

Quantifying the role and contribution of the world's oceans in past, present, and future global change is an essential goal in climate and paleoenvironmental studies. Although the global oceans influence climate greatly, the marine environment is substantially underrepresented in key climate assessment reports, especially during the last millennium. Over the past decades multicentury climate time series have emerged from tropical corals, and more recently from mid-latitude long-lived bivalves. However, subarctic and arctic proxy archival records are sparse. In order to fill this gap, a number of studies have demonstrated that mid- and high-latitude crustose coralline algae are an emerging extratropical marine environmental archive as they are amongst the longest lived shallow marine calcified organisms with life spans of several hundred years. More importantly, coralline algae occur in subarctic and arctic latitudes, both in the Pacific and Atlantic, where other high-resolution century-scale marine environmental proxies are non-existent. Hence, coralline algae have recently started to fill an important niche in marine paleoenvironmental proxy research, with several decadally to seasonally-resolved multicentury climate reconstructions published to date. This proposal will address two key themes to be answered using coralline proxy archives: A) Recently collected coralline algae from central and northern Labrador will be used to provide the first >500 year record of Labrador Current temperature and salinity variability and related climate oscillations in the northwestern Atlantic - a region where poorly understood climate and oceanographic changes have had a dramatic impact on ecosystems and fishery yields. B) Ongoing ocean acidification has been shown to potentially have a detrimental impact on the skeletons of calcareous plants and animals such as shellfish and corals. This is especially true in cold-water regions such as the subarctic North Pacific and northwest Atlantic, which are predicted to be amongst the first negatively affected by a decreasing ocean pH. Coralline algae from both oceans will be analyzed for temporal changes in skeletal structure and elemental composition, and as a proxy for reconstructing ocean pH over several centuries.

量化世界海洋在过去、现在和未来全球变化中的作用和贡献是气候和古环境研究的一个基本目标。尽管全球海洋对气候影响很大，但海洋环境在主要气候评估报告中的代表性却严重不足，特别是在上个千年期间。在过去的几十年里，热带珊瑚出现了多个世纪的气候时间序列，最近又出现在中纬度长寿双壳类动物中。然而，亚北极和北极代理档案记录很少。为了填补这一空白，许多研究表明，中高纬度壳状珊瑚藻是一种新兴的温带海洋环境档案，因为它们是寿命最长的浅海钙化生物之一，寿命可达数百年。更重要的是，珊瑚藻出现在太平洋和大西洋的亚北极和北极纬度地区，而这些地区不存在其他高分辨率的世纪规模海洋环境指标。因此，珊瑚藻最近开始在海洋古环境代理研究中占据重要地位，迄今为止已发表了几项十年至季节性解决的多世纪气候重建数据。该提案将解决使用珊瑚代理档案来回答的两个关键主题：A）最近从拉布拉多中部和北部收集的珊瑚藻将用于提供拉布拉多当前温度和盐度变化以及相关气候振荡的第一个> 500年记录西北大西洋——人们对该地区的气候和海洋变化知之甚少，对生态系统和渔业产量产生了巨大影响。 B) 持续的海洋酸化已被证明可能对钙质植物和动物（如贝类和珊瑚）的骨骼产生有害影响。 在亚北极北太平洋和西北大西洋等冷水地区尤其如此，预计这些地区将首先受到海洋 pH 值下降的负面影响。 将分析来自两个海洋的珊瑚藻的骨骼结构和元素组成的时间变化，并作为重建几个世纪以来海洋 pH 值的代理。