A potential source of organic pollutants into the northeastern Atlantic: the outflow of the Mediterranean deep-lying waters through the Gibraltar Strait.
A potential source of organic pollutants into the northeastern Atlantic: the outflow of the Mediterranean deep-lying waters through the Gibraltar Strait.
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进入东北大西洋的有机污染物的潜在来源：地中海深层水域通过直布罗陀海峡流出。
DOI：
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发表时间：
2001
影响因子：
11.4
通讯作者：
J. Albaigés
中科院分区：
文献类型：
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作者：
Soledad Marti;Josep M. Bayona;J. Albaigés
在东北大西洋地区的水柱（50-3000 m）中收集了小型和大型颗粒，该地区通过直布罗陀海峡流出的地中海深水沃茨在中部深度合并。通过水过滤（0.7微米孔径）和通过neuston网（50微米筛目尺寸）的垂直拖曳收集的颗粒被分析有机污染物，即脂肪族和芳香族烃，和有机氯化合物。小颗粒是颗粒有机碳和疏水性有机污染物的最大组成部分。正构烷烃（C14-C35）、芳烃（12种母体化合物）、多氯联苯（7种同系物）和滴滴涕（DDT + DDE）的表面浓度分别为50-63 ng/L、23-68 pg/L、8-13 pg/L和0.05-1.7 pg/L。这些浓度随深度普遍下降，特别是在上200米显着，一致的POC含量。随着深度的组成变化也很明显，在小尺寸的颗粒，包括低分子量的正构烷烃和低氯化多氯联苯同系物的消耗，以及减少化石热解多环芳烃的比例。在中深度（900-1100米）观察到浓度异常增加，表明通过就地形成或通过地中海平流输送的额外颗粒输入。后者被认为是因为小尺寸的颗粒在这些水脉表现出的垂直序列和类似的深地中海沃茨的分布模式。经初步计算，这些地中海沃茨对东北大西洋的贡献分别为每年8吨和0.5吨的上述多环芳烃和多氯联苯化合物。
Small and large-size particles were collected in the water column (50-3000 m) of a Northeastern Atlantic area where deep Mediterranean waters, outflowing through the Strait of Gibraltar, are incorporated at mid-depth. Particles collected by water filtration (0.7 micron pore size) and by vertical hauls of a neuston net (50 microns mesh size) were analyzed for organic pollutants, namely aliphatic and aromatic hydrocarbons, and organochlorine compounds. Small-size particles represented the largest bulk of particulate organic carbon as well as of hydrophobic organic pollutants. Surface concentrations of n-alkanes [C14-C35), aromatic hydrocarbons (12 parent compounds), PCBs (7 congeners), and DDTs (DDT + DDE) were, respectively, in the range of 50-63 ng/L, 23-68 pg/L, 8-13 pg/L, and 0.05-1.7 pg/L. These concentrations showed a general decrease with depth, particularly significant in the upper 200 m, consistently with the POC contents. Compositional changes with depth were also evident in small-size particles and included the depletion of low molecular weight n-alkanes and low chlorinated PCB congeners as well as a decrease of the fossil to pyrolytic PAHs ratio. Unusual increases of concentrations were observed at mid-depths (900-1100 m), indicating additional particle inputs, either by in-situ formation or by advective transport from the Mediterranean. The latter was recognized because small-size particles within these water veins exhibited distribution patterns out of the vertical sequence and similar to those of deep Mediterranean waters. An input of 8 and 0.5 tons per year of the above PAH and PCB compounds, respectively, has tentatively been calculated as the contribution of these Mediterranean waters to the Northeastern Atlantic.