Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, via Brecce Bianche 60131, Ancona, Italy.
Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, via Brecce Bianche 60131, Ancona, Italy.
Chemosphere. 2017 Oct;185:1122-1135. doi: 10.1016/j.chemosphere.2017.07.087. Epub 2017 Jul 24.
During the austral summer 2011-2012, the metal quotas of Cd, Pb and Cu in the phytoplankton of Terra Nova Bay (TNB, Antarctica) were measured for the first time. Evolution of all the three metal distributions between dissolved and particulate fractions during the season was also evaluated. Metal concentrations were mainly affected by the dynamic of the pack ice melting and phytoplankton activity. In mid-December when TNB area was covered by a thick pack ice layer and phytoplankton activity was very low, all the three metals were present mainly in their dissolved species. When the pack ice started to melt and the water column characteristics became ideal (i.e. moderate stratification, ice free area), the phytoplankton bloom occurred. Cd showed a nutrient-type behaviour with dissolved and particulate fractions mainly influenced by phytoplankton activity. Cd quota showed a mean value of 0.12 ± 0.07 nmol L (30-100% of the total particulate). Also Cu showed a nutrient-type behaviour, with its quota in phytoplankton varying between 0.08 and 2.1 nmol L (20-100% of the total particulate). Pb features the typical distribution of a scavenged element with very low algal content (0.03 ± 0.02 nmol L, representing 20-50% of the total particulate). The vertical distribution of this element was influenced by several factors (e.g. pack ice melting, atmospheric inputs), the phytoplankton activity affecting Pb behaviour only partially. Metal:C ratios provide valuable information on the biological requirements for Cd, Pb and Cu, leading us to better understand their biogeochemical cycles.
在 2011-2012 年南极夏末期间,首次测量了南极特内纳湾(Terra Nova Bay,TNB)浮游植物中的 Cd、Pb 和 Cu 的金属配额。还评估了整个季节中所有三种金属在溶解和颗粒部分之间的分布变化。金属浓度主要受冰的动态融化和浮游植物活动的影响。12 月中旬,当 TNB 区域被厚厚的冰层覆盖且浮游植物活动非常低时,所有三种金属主要以溶解形式存在。当冰层开始融化且水柱特征变得理想(即适度分层,无冰区)时,浮游植物大量繁殖。Cd 表现出营养型行为,溶解和颗粒部分主要受浮游植物活动的影响。Cd 配额的平均值为 0.12±0.07 nmol·L(占总颗粒的 30-100%)。Cu 也表现出营养型行为,其在浮游植物中的配额在 0.08 和 2.1 nmol·L 之间变化(占总颗粒的 20-100%)。Pb 具有被清除元素的典型分布,其藻类含量非常低(0.03±0.02 nmol·L,占总颗粒的 20-50%)。该元素的垂直分布受多种因素的影响(例如冰的融化、大气输入),浮游植物活动仅部分影响 Pb 的行为。金属:C 比提供了有关 Cd、Pb 和 Cu 的生物需求的有价值信息,使我们能够更好地了解它们的生物地球化学循环。