Changes in sulfur cycling in a large lake during the Paleocene-Eocene Thermal Maximum and implications for lake deoxygenation
Changes in sulfur cycling in a large lake during the Paleocene-Eocene Thermal Maximum and implications for lake deoxygenation
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古新世-始新世热最大值期间大型湖泊硫循环的变化及其对湖泊脱氧的影响
DOI：
10.1016/j.gloplacha.2021.103716
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发表时间：
2021-11
影响因子：
3.9
通讯作者：
Zhongli Ding
中科院分区：
文献类型：
--
作者：
Xu Wangle;Lianjun Feng;Fred J. Longstaffe;Zuoling Chen;Min Zhu;Hongwei Li;Linlin Cui;Guangpeng Du;Zhongli Ding
了解全球变暖对大型湖泊的生物地球化学影响是管理水生资源的核心。古新世-始新世最高温度(PETM)代表了当前全球变暖引起的潜在影响的极好的古模拟。利用与碳酸盐有关的硫酸盐硫、氧同位素，重建了现代中国中部一个大型湖泊在古近纪时期的氧化还原动态变化。与密集的微生物硫酸盐还原(MSR)相关的三个主要缺氧期(AE)表明，硫和氧同位素组成较高，和/或硫酸盐含量较低。湖泊中的热成层作用可能是造成缺氧和硫的地球化学循环变化的主要原因。前两次事件发生在PETM的初始阶段。它们的特点是硫酸盐和总有机碳减黑碳(TOC-BC)含量较低，表明生物生产力较低，这与分层和缺氧水体中有限的营养循环有关。第三次声发射发生在PETM高峰期。它的特征是极低的硫酸盐和高的TOC-BC含量，可能是近地表生产力增加和较低水柱缺氧的产物。由严重变暖引发的加强的水文循环可能增加了进入湖泊的陆地营养通量，导致了表层湖泊生产力的增加。然而，缺氧/硫化物地带的向上扩张可能通过收缩其宜居空间而抑制了湖泊生态系统。我们的结果表明，当前的全球变暖可能会在大型湖泊中引发类似的生态压力。
Understanding the biogeochemical effects of global warming on large lakes is central to managing aquatic resources. The Paleocene-Eocene Thermal Maximum (PETM) presents an excellent paleo-analog for potential impacts arising from current global warming. Here, we reconstructed dynamic redox changes in a large lake located in modern Central China during the PETM, using carbonate-associated sulfate sulfur and oxygen isotopes. Three major anoxic episodes (AE) associated with intensive microbial sulfate reduction (MSR) were identified, as indicated by higher sulfur and oxygen isotope compositions, and/or decreased sulfate contents. Thermal stratification in the lake was the likely main cause of the anoxia and associated changes in sulfur geochemical cycles. The first two AEs occurred during the initial stage of PETM. They are characterized by low sulfate and total organic carbon-minus-black carbon (TOC-BC) contents, suggestive of low biological productivity related to limited nutrient cycling in a stratified and anoxic water mass. The third AE occurred during the peak of the PETM. It was characterized by extremely low sulfate and high TOC-BC contents, possibly the product of increased near-surface productivity coupled with anoxia in the lower water column. An intensified hydrological cycle triggered by severe warming may have enhanced terrestrial nutrient fluxes to the lake, leading to increased surficial lake productivity. Upward expansion of the anoxic/sulfidic zone, however, may have suppressed the lake ecosystem by contracting its livable space. Our results suggest that current global warming could trigger similar ecological stress in large lakes.
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影响因子：
5
作者：
Brunner, B;Bernasconi, SM;Schroth, MH
通讯作者：
Schroth, MH
影响因子：
3
作者：
T. Goldberg;A. Mazumdar;H. Strauss;G. Shields
通讯作者：
T. Goldberg;A. Mazumdar;H. Strauss;G. Shields
DOI：
10.1073/pnas.1218874110
发表时间：
2013-07-09
影响因子：
11.1
作者：
Leavitt, William D.;Halevy, Itay;Johnston, David T.
通讯作者：
Johnston, David T.
中国古新世-始新世热极增温对降水空间变化的响应
影响因子：
3.9
作者：
Chen, Zuoling;Dong, Xinxin;Ding, Zhongli
通讯作者：
Ding, Zhongli
影响因子：
5
作者：
Gomes, Maya L.;Johnston, David T.
通讯作者：
Johnston, David T.