Influence of nitrate-storing sulfur bacteria on the nitrogen and phosphorus cycle of the ocean

储存硝酸盐的硫细菌对海洋氮磷循环的影响

• 批准号: 5411290
• 负责人: Professorin Dr. Heide Schulz-Vogt
• 金额: --
• 依托单位: Leibniz-Institut für Ostseeforschung Warnemünde (IOW)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2003
• 资助国家: 德国
• 起止时间: 2002-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5411290?language=en
• 关键词: Influence; nitrate; storing; sulfur; bacteria

Nitrate-storing sulfur bacteria are abundant in most marine sediments containing free hydrogen sulfide and may reach very high biomasses. Apart from their importance for the oxidative part of the marine sulfur cycle they also interfere with the nitrogen cycle of the sediment. Until now there are indications for three different ways in which sulfur bacteria may change the total nitrogen budget of their habitats: denitrification, dissimilatory reduction of nitrate to ammonia and possibly even nitrogen fixation. Under certain conditions they may also produce significant amounts of nitrous oxide, which is a green house gas. The first goal of this project is to investigate under which conditions each of these processes occur. Preliminary studies have also shown that all nitrate-storing sulfur bacteria investigated so far contain high amounts of internally stored polyphosphate. This finding indicates that this group of bacteria may also have great influence on the phosphorus cycle of the ocean, especially as they occur in very high biomasses in some areas where recent phosphorite genesis is found. Therefore, the second focus of this project is to carry out physiological experiments and field investigations concerning the accumulation and release of polyphosphate.

硝酸盐储存硫细菌在大多数含有游离硫化氢的海洋沉积物中很丰富，并可能达到非常高的生物量。除了它们对海洋硫循环的氧化部分的重要性外，它们还干扰沉积物的氮循环。到目前为止，有迹象表明硫细菌可能以三种不同的方式改变其栖息地的总氮收支：反硝化作用，硝酸盐异化还原为氨，甚至可能是固氮作用。在某些条件下，它们还可能产生大量的一氧化二氮，这是一种绿色家用气体。本项目的第一个目标是调查这些过程发生的条件。初步研究还表明，迄今为止研究的所有硝酸盐储存硫细菌都含有大量的内部储存的多磷酸盐。这一发现表明，这群细菌可能对海洋的磷循环也有很大的影响，特别是因为它们出现在一些最近发现磷质岩成因的地区的生物量非常高，因此，本项目的第二个重点是开展有关聚磷酸盐积累和释放的生理实验和现场调查。