由RV Alexander von Humbolt在纳米比亚沿海水域获得数据显示，由含硫化物的海水覆盖的面积大约为7000平方公里的一个非洲沿海大陆架区域，因细菌的作用而消除了毒性：对生物有害的硫化物被氧化成无毒的胶体硫和硫酸盐。
沿海水域的富营养化（经常是由人类活动引起的）会导致藻类繁盛，引起氧的严重消耗和硫化氢的间歇性出现，对生态系统产生灾难性后果。关于硫化物会被亚表层海水中的细菌完全耗尽、从而会被浅层沿海水域的遥感或监测活动忽略的发现表明，大陆架上含硫化物的海底水域也许要比我们所想的更普遍，所以有可能对底栖生物群落产生一个重要的、但以前却被忽略的影响。(生物谷Bioon.com)
生物谷推荐原始出处：
Nature 457, 581-584 (29 January 2009) | doi:10.1038/nature07588
Detoxification of sulphidic African shelf waters by blooming chemolithotrophs
Gaute Lavik1,5, Torben Stührmann1,5, Volker Brüchert1,6, Anja Van der Plas2, Volker Mohrholz3, Phyllis Lam1, Marc Mumann4, Bernhard M. Fuchs1, Rudolf Amann1, Ulrich Lass3 & Marcel M. M. Kuypers1
1 Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, D-28359 Bremen, Germany
2 National Marine Information & Research Centre Ministry of Fisheries & Marine Resources, PO Box 912, Swakopmund, Namibia
3 Baltic Sea Research Institute Warnemünde, Seestrasse 15, D-18119 Rostock, Germany
4 Department of Microbial Ecology, Vienna Ecology Centre, University of Vienna, Althanstrae 14, A-1090 Vienna, Austria
Coastal waters support 90 per cent of global fisheries and are therefore an important food reserve for our planet1. Eutrophication of these waters, due to human activity, leads to severe oxygen depletion and the episodic occurrence of hydrogen sulphide—toxic to multi-cellular life—with disastrous consequences for coastal ecosytems2, 3, 4, 5. Here we show that an area of 7,000 km2 of African shelf, covered by sulphidic water, was detoxified by blooming bacteria that oxidized the biologically harmful sulphide to environmentally harmless colloidal sulphur and sulphate. Combined chemical analyses, stoichiometric modelling, isotopic incubations, comparative 16S ribosomal RNA, functional gene sequence analyses and fluorescence in situ hybridization indicate that the detoxification proceeded by chemolithotrophic oxidation of sulphide with nitrate and was mainly catalysed by two discrete populations of - and -proteobacteria. Chemolithotrophic bacteria, accounting for 20 per cent of the bacterioplankton in sulphidic waters, created a buffer zone between the toxic sulphidic subsurface waters and the oxic surface waters, where fish and other nekton live. This is the first time that large-scale detoxification of sulphidic waters by chemolithotrophs has been observed in an open-ocean system. The data suggest that sulphide can be completely consumed by bacteria in the subsurface waters and, thus, can be overlooked by remote sensing or monitoring of shallow coastal waters. Consequently, sulphidic bottom waters on continental shelves may be more common than previously believed, and could therefore have an important but as yet neglected effect on benthic communities.
