Biogeochemical feedbacks may amplify ongoing and future ocean deoxygenation: a case study from the Peruvian oxygen minimum zone
Biogeochemical feedbacks may amplify ongoing and future ocean deoxygenation: a case study from the Peruvian oxygen minimum zone
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生物地球化学反馈可能会加剧正在进行和未来的海洋脱氧：秘鲁最低氧气区的案例研究
DOI：
10.1007/s10533-022-00908-w
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发表时间：
2022
期刊：
影响因子：
4
通讯作者：
A. Oschlies
中科院分区：
文献类型：
--
作者：
K. Wallmann;Y. José;M. Hopwood;C. Somes;A. Dale;F. Scholz;E. Achterberg;A. Oschlies
采用一种新的箱形模型模拟了秘鲁最低含氧带（OMZ）中营养盐的氧依赖循环。模型结果和OMZ的现状的数据表明，溶解铁是限制营养素的初级生产，并提供了溶解亚铁从货架和斜坡沉积物的释放。大多数活性氮的去除是通过铵的厌氧氧化进行的，其中铵是通过好氧有机氮降解来输送的。模拟海洋脱氧和变暖的影响的模型实验表明，秘鲁OMZ的生产力将增加，由于溶解铁从陆架和斜坡沉积物的释放增强。一个正反馈循环植根于氧气依赖的底栖铁释放放大，这两个，生产力的上升和氧气的下降，在周围的底层沃茨。因此，氧气供应量每减少1%，大陆边地下沃茨的氧气浓度就会减少22%。生产力提高和脱氧作用增强的趋势将继续下去，直到活性氮的损失限制了浮游植物的进一步生长。在氮限制下，OMZ的氧化还原状态通过负反馈来稳定。只有在缺氧条件下固氮速率急剧增加，才有可能进一步提高生产率并过渡到硫化物条件。这种转变将导致有毒硫化物的广泛积累，对秘鲁外保区的渔业产量产生不利影响，目前该地区的渔业产量占全球渔获量的很大一部分。
A new box model is employed to simulate the oxygen-dependent cycling of nutrients in the Peruvian oxygen minimum zone (OMZ). Model results and data for the present state of the OMZ indicate that dissolved iron is the limiting nutrient for primary production and is provided by the release of dissolved ferrous iron from shelf and slope sediments. Most of the removal of reactive nitrogen occurs by anaerobic oxidation of ammonium where ammonium is delivered by aerobic organic nitrogen degradation. Model experiments simulating the effects of ocean deoxygenation and warming show that the productivity of the Peruvian OMZ will increase due to the enhanced release of dissolved iron from shelf and slope sediments. A positive feedback loop rooted in the oxygen-dependent benthic iron release amplifies, both, the productivity rise and oxygen decline in ambient bottom waters. Hence, a 1% decline in oxygen supply reduces oxygen concentrations in sub-surface waters of the continental margin by 22%. The trend towards enhanced productivity and amplified deoxygenation will continue until further phytoplankton growth is limited by the loss of reactive nitrogen. Under nitrogen-limitation, the redox state of the OMZ is stabilized by negative feedbacks. A further increase in productivity and transition to sulfidic conditions is only possible if the rate of nitrogen fixation increases drastically under anoxic conditions. Such a transition would lead to a wide-spread accumulation of toxic sulfide with detrimental consequences for fishery yields in the Peruvian OMZ that currently provides a significant fraction of the global fish catch.
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颗粒相是控制北大西洋（亚）热带溶解铁浓度的关键
影响因子：
5.2
作者：
Milne A
通讯作者：
Milne A
赤道和北太平洋 50 至 300 m 深度的氧和营养物的趋势和年代际振荡
影响因子：
4.9
作者：
Stramma;Schmidtko;Bograd;Sasano;Whitney
通讯作者：
Whitney
DOI：
10.1038/ismej.2014.71
发表时间：
2014-05
期刊：
The ISME Journal
影响因子：
--
作者：
C. Loescher;T. Grosskopf;Falguni Desai;D. Gill;H. Schunck;P. Croot;C. Schlosser;S. Neulinger;N. Pinnow;G. Lavik;M. Kuypers;J. LaRoche;R. Schmitz
通讯作者：
C. Loescher;T. Grosskopf;Falguni Desai;D. Gill;H. Schunck;P. Croot;C. Schlosser;S. Neulinger;N. Pinnow;G. Lavik;M. Kuypers;J. LaRoche;R. Schmitz
DOI：
10.1073/pnas.1905553116
发表时间：
2019-11
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
B. Naafs;F. Monteiro;A. Pearson;M. B. Higgins;R. Pancost;A. Ridgwell;A. Ridgwell
通讯作者：
B. Naafs;F. Monteiro;A. Pearson;M. B. Higgins;R. Pancost;A. Ridgwell;A. Ridgwell
影响因子：
4.5
作者：
A. Noffke;C. Hensen;S. Sommer;F. Scholz;L. Bohlen;T. Mosch;M. Graco;K. Wallmann
通讯作者：
A. Noffke;C. Hensen;S. Sommer;F. Scholz;L. Bohlen;T. Mosch;M. Graco;K. Wallmann