AMMONIUM REGENERATION IN THE SCOTIA-WEDDELL CONFLUENCE AREA DURING SPRING 1988
AMMONIUM REGENERATION IN THE SCOTIA-WEDDELL CONFLUENCE AREA DURING SPRING 1988
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DOI：
10.3354/meps078241
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发表时间：
1991-12-01
影响因子：
2.5
通讯作者：
BAEYENS, W
中科院分区：
文献类型：
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作者：
GOEYENS, L;TREGUER, P;BAEYENS, W
在斯科蒂亚-威德尔汇流区存在大量的铵库存和相关的微异养生物数量的增加表明那里铵矿化过程的重要性。在边缘冰区的最大铵浓度超过2 μ mol N l-1和在这个区域的矿化率始终高于在邻近的公海和永久冰覆盖区测得的。在一个站，其特点是一个大的杀群，再矿化率为18 nmol N l-1 h-1;在边缘冰区的速率一般在5和9 nmol N l-1 h-1之间。原生动物的活动是最重要的生态化过程中，只有在磷虾事件是一个非常高的细菌活动观察。磷虾的存在并不直接导致铵池，但可能会引发藻类碎片和粪便颗粒中的细菌分解活动。增加的矿化导致水中铵的可用性增强，并降低植物生长素硝酸盐同化的f-比率。然而，硝酸盐的吸收至少有30%的无机氮同化，显着高于贫营养系统的测量值。
The presence of large ammonium stocks and the related enhanced quantities of microheterotrophs in the Scotia-Weddell Confluence area indicate the importance of ammonium remineralization processes there. Maximal ammonium concentrations in the marginal ice zone amounted to more than 2-mu-mol N l-1 and remineralization rates in this zone were consistently higher than those measured in the adjacent open ocean and permanently ice-covered zones. At one station, characterized by a large kill swarm, the remineralization rate was 18 nmol N l-1 h-1; rates in the marginal ice zone generally ranged between 5 and 9 nmol N l-1 h-1. Protozoan activity was of predominant importance for the remineralization process; only after the krill event was a very high bacterial activity observed. The presence of krill does not contribute in a direct way to the ammonium pool, but probably initiates the bacterial breakdown activity in algal debris and faecal pellets. The increased remineralization leads to enhanced availability of ammonium in the water and to decreased f-ratios for phytoplanktonic nitrate assimilation. Nevertheless, nitrate uptake represented at least 30% of inorganic nitrogen assimilation, significantly higher than values measured for oligotrophic systems.