Calcium carbonate dissolution experiment Phase 1: Effect of elevated pCO2 on sediment dissolution.

<p>Effect of elevated pCO2 on sediment dissolution. Data are results of Phase 1 of the sediment dissolution experiment described in:</p>

<p>Lantz, C. A., Carpenter, R. C. and Edmunds, P. J.: Calcium carbonate (CaCO3) sediment dissolution under elevated concentrations of carbon dioxide (CO2) and nitrate (NO3−). (2017) J. Exp. Mar. Bio. Ecol., 495,&nbsp;May, 48–56. doi:&nbsp;<a href=\"http://doi.org/10.1016/j.jembe.2017.05.014\">http://doi.org/10.1016/j.jembe.2017.05.014</a></p>

<p>The alkalinity anomaly technique was employed to measure changes in seawater total alkalinity inside of stirred benthic chambers.&nbsp;Water samples (75 mL) were taken at the beginning and end of each incubation from 0.6 cm diameter polyvinyl chloride in-line tubes connected to the side of the chamber, and these were used to measure seawater temperature, salinity, pH, and total alkalinity (TA). Temperature was recorded with a thermometer (± 0.05 ^oC; ThermoFisher Traceable^®) and salinity was measured with a bench-top conductivity meter (± 0.1 psu, YSI^® 3100). TA and pH were measured within one hour of sample collection. Seawater collected for TA was filtered (0.45 µm; Chanson and Millero, 2007) and analyzed using potentiometric titrations with 0.1-N HCl using an automatic titrator (Mettler Toledo T50) (Dickson et al., 2007). Seawater pH was measured as mV and temperature with a potentiometric electrode (Orion ROSS pH/ATC Triode) and converted to the total scale (pH_T) using a calibration relationship prepared using Tris-buffers (Nemzer and Dickson, 2005).</p>

<p>See the publication for a detailed overview of the methodology.</p>

<p>高二氧化碳分压（pCO₂）对沉积物溶解的影响。本数据集为沉积物溶解实验第一阶段的研究结果，相关实验细节见于：</p>
<p>Lantz, C. A.、Carpenter, R. C. 及 Edmunds, P. J.：《碳酸钙（CaCO₃）沉积物在二氧化碳（CO₂）与硝酸盐（NO₃⁻）浓度升高条件下的溶解过程》（2017）《实验海洋生物与生态学杂志》（J. Exp. Mar. Bio. Ecol.），第495卷，5月刊，第48-56页。DOI：<a href="http://doi.org/10.1016/j.jembe.2017.05.014">http://doi.org/10.1016/j.jembe.2017.05.014</a></p>
<p>本研究采用碱度异常法，测定搅拌式底栖培养舱内海水总碱度的变化。于每个培养周期的起始与结束阶段，从连接于舱体侧壁的0.6 cm直径聚氯乙烯（polyvinyl chloride, PVC）在线取样管中采集75 mL水样，用于测定海水温度、盐度、pH值及总碱度（total alkalinity, TA）。温度采用精密温度计记录（精度±0.05 ℃；赛默飞世尔ThermoFisher Traceable^®）；盐度通过台式电导率仪测定（精度±0.1 psu，YSI^® 3100）。总碱度与pH值的测定需在水样采集后1小时内完成。用于总碱度测定的海水样品经0.45 µm滤膜过滤（Chanson与Millero, 2007），并采用自动滴定仪（梅特勒托利多Mettler Toledo T50）以0.1 N盐酸进行电位滴定分析（Dickson等, 2007）。海水pH值以电位法通过Orion ROSS pH/ATC Triode电极测定，记录mV值与温度，并通过Tris缓冲液校准曲线转换至总尺度（pH_T）（Nemzer与Dickson, 2005）。</p>
<p>实验方法的详细概述请参阅上述发表文献。</p>