Effects of tide and season changes on the iron-sulfur-phosphorus biogeochemistry in sediment porewater of a mangrove coast
Effects of tide and season changes on the iron-sulfur-phosphorus biogeochemistry in sediment porewater of a mangrove coast
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潮汐和季节变化对红树林海岸沉积物孔隙水中铁硫磷生物地球化学的影响
DOI：
10.1016/j.jhydrol.2018.11.002
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发表时间：
2019
影响因子：
6.4
通讯作者：
Aiguo Gao
中科院分区：
文献类型：
--
作者：
Feng Pan;Huatai Liu;Zhanrong Guo;Zhiwei Li;Bo Wang;Yu Cai;Aiguo Gao
为了更好地理解铁、硫和磷的地球化学过程及其耦合关系，我们采用原位高分辨率薄膜扩散梯度（DGT）技术对九龙江口红树林海岸沉积物间隙水中不稳定的铁、硫和磷进行了表征。DGT不稳定态Fe和S的分布表明，微生物硫酸盐还原（MSR）和微生物铁还原（MIR）具有强烈的竞争关系和温度依赖性。因此，除了预期的MSR，MIR是一个重要的，甚至是主要的有机质（OM）矿化在这个富铁红树林海岸的地球化学过程。不稳定的Fe，S和P的分布和变化表明，Fe氧化还原循环在调节P行为和P循环中起着至关重要的作用。另外一个新的发现是，不稳定的S在潮间带的通量增加涨潮和落潮期间减少，表明在表层硫化物的形成和再氧化的潮汐引起的氧化还原变化的调节。在冬季调查中，与循环海水相关的净P通量估计为-0.306 ± 0.001 ~ 0.343 ± 0.013 mmol m−2d− 1，表明沉积物孔隙水在冬季倾向于成为潮下带的P源和潮间带上覆海水的P汇。表层沉积物中活性磷的持续积累可能在随后的汛期通过MIR过程向上覆海水中释放，促进邻近厦门湾的富营养化。
To better understand the biogeochemical processes of iron, sulfur, and phosphorus and their coupled relationships, we used thein situhigh-resolution diffusive gradients in thin films (DGT) technique to characterize labile Fe, S, and P in the sediment porewater of a mangrove coast in the Jiulong River Estuary, China. The distributions of DGT-labile Fe and S indicated that microbial sulfate reduction (MSR) and microbial iron reduction (MIR) exhibited an intense competitive relationship and temperature-dependent behavior. Thus, in addition to the expected MSR, MIR is an important or even predominant biogeochemical process for organic matter (OM) mineralization in this Fe-rich mangrove coast. Labile Fe, S, and P distributions and variations demonstrate that Fe redox cycling plays a crucial role in regulating P behavior and P cycling. An additional new finding is that the flux of labile S in the intertidal zone increases during flood tides and decreases during ebb tides, indicating that the formation and reoxidation of sulfide in surface layers are regulated by tide-induced redox changes. The net P flux associated with recirculated seawater was estimated to range from −0.306 ± 0.001 to 0.343 ± 0.013 mmol m−2d−1in the winter survey, suggesting that sediment porewater tends to be a P source in the subtidal zone and a P sink in the intertidal zone for the overlying seawater in winter. The continuous accumulation of labile P in surface sediment could be intensively released into the overlying seawater through prevailing MIR process in the subsequent riverine flood season, which may promote eutrophication of the adjacent Xiamen Bay.
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影响因子：
1.6
作者：
S. Theberge;George W. Luther III
通讯作者：
S. Theberge;George W. Luther III
影响因子：
5.5
作者：
Mortimer, CH
通讯作者：
Mortimer, CH
影响因子：
4.5
作者：
Anschutz, P;Zhong, SJ;Gobeil, C
通讯作者：
Gobeil, C
影响因子：
3.5
作者：
P. Dobbin;A. Powell;A. McEwan;D. Richardson
通讯作者：
P. Dobbin;A. Powell;A. McEwan;D. Richardson
影响因子：
4.3
作者：
David Robertson;D. Welsh;P. Teasdale
通讯作者：
David Robertson;D. Welsh;P. Teasdale