FP 35: Quaternary marine ecosystem response to fertilization: Mediterranean sapropel events and implications for marine carbon uptake

FP 35：第四纪海洋生态系统对施肥的响应：地中海腐泥事件及其对海洋碳吸收的影响

• 批准号: 5447608
• 负责人: Professor Dr. Kay-Christian Emeis
• 金额: --
• 依托单位: Departament de Geografia
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5447608?language=en
• 关键词: FP; 35; Quaternary; marine; ecosystem

Within the Late Quaternary record of the Eastern Mediterranean basin, sapropel horizons indicating periodic anoxia have long been recognised. Recent research has shown that these form in response to natural fertilization of the Mediterranean Sea and occur every 23.000 years, suggesting that the forcing mechanism is a precessional modulation of monsoon strenght. The mechanisms of ecologcial change and propagation of nutrients through the surface ocean ecosystem remain poorly constrained. This limits our ability to use anoxic events to predict likely analogue situations as a result of present day climate change and eutrophication. A new multi-proxy approach will be implemented to reconstruct both, the extent of the response in marine productivity and the supporting nutrient fluxes to climate change. Further, we aim to monitor changes in the carbon system by analysing the key Mediterranean calcifying marine phytoplankton, coccolithophorids. To quantify the change in trophic conditions in the past, we will refine our proxies using a unique combination of culture samples, sediment trap material, core top sediments, and sub-recent sediments... These refined proxies will then be applied to time intervals corresponding to three defined phases of enhanced fertility over the last 200 kyr...

在东地中海盆地第四纪晚期的记录中，表明周期性缺氧的腐蚀层早已被认识到。最近的研究表明，这种现象是对地中海自然肥化的响应，每隔23.000年发生一次，这表明强迫机制是季风强度的进动调制。生态变化和营养物质通过表层海洋生态系统传播的机制仍然受到很少的限制。这限制了我们使用缺氧事件来预测由于当今气候变化和富营养化而可能出现的模拟情况的能力。将采用一种新的多指标方法来重建海洋生产力的响应程度和支持气候变化的营养通量。此外，我们的目标是通过分析关键的地中海钙化海洋浮游植物--球藻，来监测碳系统的变化。为了量化过去营养条件的变化，我们将使用培养样本、沉积物捕集器材料、岩心顶部沉积物和次现代沉积物的独特组合来精炼我们的替代品。然后，这些精炼的代用指标将被应用于与过去200年来生育率提高的三个定义阶段相对应的时间间隔。