Biometry and dissolution features of the benthic foraminifer Ammonia aomoriensis at high pCO2
Biometry and dissolution features of the benthic foraminifer Ammonia aomoriensis at high pCO2
复制标题
DOI：
10.3354/meps09138
复制
发表时间：
2011-01-01
影响因子：
2.5
通讯作者：
Polovodova, Irina
中科院分区：
文献类型：
--
作者：
Haynert, Kristin;Schoenfeld, Joachim;Polovodova, Irina
对波罗的海西部弗伦斯堡峡湾的底栖有孔虫 Ammonia aomoriensis 进行了培养实验。这些实验模拟了大气中二氧化碳浓度的预计上升。我们将样本暴露于 5 个海水 pCO(2) 水平（范围从 618 mu atm (pH 7.9) 到 3130 mu atm (pH 7.2)）中 6 周。 pCO(2) 处理之间的生长率和死亡率存在显着差异。在 618 mu atm 处观察到平均测试直径的最大增加 (19%)。在分压 >1829 mu atm 时，观察到平均测试直径减少，在 3130 mu atm 时减少高达 22%。在 pCO(2) 水平为 618 和 751 mu atm 时，实验后发现青森菌测试完好无损。在929和1829μatm下培养的样品的外室因腐蚀而严重损坏。对在 3130 mu atm 下孵化的标本进行目视检查，发现所有外室的壁都溶解了，只有内部有机衬里保持完好。我们的结果表明，波罗的海水域中的 pCO(2) 值 >= 929 mu atm 会导致青蒿的生长减少并导致壳溶解。夏季和秋季，弗伦斯堡峡湾和邻近地区的底层水域的 pCO(2) 水平经常处于此范围内。大气中二氧化碳浓度的增加可能会延长和加剧这些欠饱和期。这最终可能会减慢青森的钙化速度，直至净碳酸盐沉淀终止。该物种可能从波罗的海和其他容易出现季节性欠饱和的地区消失，可能会在不久的将来导致浅水底栖生态系统发生重大变化。
Culturing experiments were performed with the benthic foraminifer Ammonia aomoriensis from Flensburg Fjord, western Baltic Sea. The experiments simulated a projected rise in atmospheric CO2 concentrations. We exposed specimens to 5 seawater pCO(2) levels ranging from 618 mu atm (pH 7.9) to 3130 mu atm (pH 7.2) for 6 wk. Growth rates and mortality differed significantly among pCO(2) treatments. The highest increase of mean test diameter (19%) was observed at 618 mu atm. At partial pressures >1829 mu atm, the mean test diameter was observed to decrease, by up to 22% at 3130 mu atm. At pCO(2) levels of 618 and 751 mu atm, A. aomoriensis tests were found intact after the experiment. The outer chambers of specimens incubated at 929 and 1829 mu atm were severely damaged by corrosion. Visual inspection of specimens incubated at 3130 mu atm revealed wall dissolution of all outer chambers, only their inner organic lining stayed intact. Our results demonstrate that pCO(2) values of >= 929 mu atm in Baltic Sea waters cause reduced growth of A. aomoriensis and lead to shell dissolution. The bottom waters in Flensburg Fjord and adjacent areas regularly experience pCO(2) levels in this range during summer and fall. Increasing atmospheric CO2 concentrations are likely to extend and intensify these periods of undersaturation. This may eventually slow down calcification in A. aomoriensis to the extent that net carbonate precipitation terminates. The possible disappearance of this species from the Baltic Sea and other areas prone to seasonal undersaturation would likely cause significant shifts in shallow-water benthic ecosystems in the near future.