Size normalized shell weights and measurements for Neogloboquadrina pachyderma and Uvigerina peregrina from the Gulf of Alaska (IODP Exp 341) and associated environmental proxy data

Here we use volume density (ρV) measurements as a metric of size-normalized weights for Neogloboquadrina pachyderma, a planktonic foraminifer, from upper OMZ and abyssal depth sites in the Gulf of Alaska over the past ~20,000 years to test for covariation between carbonate preservation and OMZ intensity. We find that dissolution of N. pachyderma is most intense at the upper OMZ site where oxygenation is generally lower than at the abyssal site. We also examine Uvigerina peregrina, a benthic foraminifer, at the upper OMZ site and find that the lowest ρV measurements in both taxa occur during deglacial and early Holocene dysoxic events. We use computed tomography images to confirm that changes in ρV are related to shell thickness, observe dissolution features, and test for growth influences on ρV. Further, we use stepwise selection of multiple regression models in which co-registered environmental proxies are potential predictors of ρV and find that the best supported models retain negati...本研究以体积密度（volume density，记为ρ_V）作为浮游有孔虫（planktonic foraminifer）厚壁新方球虫（Neogloboquadrina pachyderma）的尺寸归一化重量指标，分析了过去约2万年间阿拉斯加湾上部含氧最低带（Oxygen Minimum Zone, OMZ）与深渊站位的相关数据，以检验碳酸盐保存与OMZ强度之间的共变关系。研究发现，厚壁新方球虫的壳体溶解作用在OMZ上部站位最为强烈，该站位的溶氧水平整体低于深渊站位。本研究同时对OMZ上部站位的底栖有孔虫（benthic foraminifer）奇异卷心虫（Uvigerina peregrina）开展分析，结果显示两个类群的最低ρ_V值均出现于冰消期及早全新世的缺氧事件期间。本研究借助计算机断层扫描（computed tomography, CT）图像证实，ρ_V的变化与壳体厚度相关，同时观察到壳体溶解特征，并检验了生长作用对ρ_V的影响。进一步，本研究采用逐步回归模型筛选法，以同步记录的环境代用指标作为ρ_V的潜在预测因子，结果表明最优拟合模型保留了负相关的……