Progress in Oceanography ( IF 4.1 ) Pub Date : 2022-08-02 , DOI: 10.1016/j.pocean.2022.102864 David J. Reynolds, Vanessa R. von Biela, Kenneth H. Dunton, David C. Douglas, Bryan A. Black
The Pacific Arctic region has experienced, and is projected to continue experiencing, rapid climate change. Large uncertainties exist in our understanding of the impact these physical changes have on the region’s ecology. This is, in part, due to the lack of long-term data. Here we investigate bivalve mollusc growth increment width chronologies (sclerochronologies) to develop a long-term biological data series in an Arctic species and address the hypothesis that benthic production in the Pacific Arctic region is in decline with implications for predators (e.g., walrus, whales, seals, and sea ducks). Growth increments formed in the shells of two bivalve mollusc species, Astarte borealis and Liocyma fluctuosa, were examined using conventional sclerochronological techniques. The A. borealis and L. fluctuosa samples exhibited measured longevities of >148 and >18 years, respectively, in the coastal waters of Alaska’s Chukchi Sea. Dendrochronology crossdating techniques facilitated the development of two robust (expressed population signal > 0.85) independent growth increment width chronologies. These chronologies provide evidence of the growth conditions through time for each species (1985–2015 for A. borealis and 1997–2014 for L. fluctuosa). Linear regression analyses identified that both species grew more rapidly in years with warmer sea surface temperature and lower sea ice concentration. The results provide evidence that benthic ecosystems are benefiting from the warmer conditions and reduced sea ice that have accompanied recent Arctic climate trends. This result is encouraging for benthic predators in the eastern Chukchi Sea as it alleviates the concern that their benthic prey has already become food limited by weakened pelagic-benthic coupling. More broadly, this initial A. borealis chronology is among the longest biological data series for any Arctic species and highlights the feasibility of multicentennial biological data for the Arctic.
中文翻译:
太平洋北极环境变异和双壳类生长的硬化年代学记录
太平洋北极地区已经经历并预计将继续经历快速的气候变化。我们对这些物理变化对该地区生态的影响的理解存在很大的不确定性。这部分是由于缺乏长期数据。在这里,我们研究双壳贝类生长增量宽度年表(sclerochronologies),以开发北极物种的长期生物数据系列,并解决太平洋北极地区底栖生物产量下降对捕食者(例如,海象、鲸鱼)影响的假设、海豹和海鸭)。使用常规的 sclerochronological 技术检查了在两种双壳贝类软体动物Astarte borealis和Liocyma fluctuosa的壳中形成的生长增量。这在阿拉斯加楚科奇海沿岸水域,A.borealis 和 L.fluctuosa 样本的测量寿命分别为 > 148 年和 > 18年。树木年代学交叉测年技术促进了两个稳健(表达的种群信号> 0.85)独立生长增量宽度年表的发展。这些年表提供了每个物种随时间推移的生长条件的证据(A.borealis 为 1985-2015年, L.fluctuosa为 1997-2014 年). 线性回归分析表明,随着海面温度升高和海冰浓度降低,这两个物种的生长速度更快。结果提供了证据,表明底栖生态系统正在受益于伴随最近北极气候趋势而来的变暖条件和减少的海冰。这一结果对楚科奇海东部的底栖捕食者来说是令人鼓舞的,因为它减轻了人们对它们的底栖猎物已经成为因远洋-底栖动物耦合减弱而受到限制的食物的担忧。更广泛地说,这个最初的A.borealis年表是任何北极物种最长的生物数据系列之一,并强调了北极多百年生物数据的可行性。