期刊
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
卷 505, 期 -, 页码 410-427出版社
ELSEVIER
DOI: 10.1016/j.palaeo.2018.06.025
关键词
Transfer function; West Equatorial Africa; Orbital forcing; Carbon cycle
资金
- Brittany Region [ANR-10-LABX-19]
- French government under the program Investissements d'Avenir
- Laboratoire d'Excellence LabexMER [ANR-10-LABX-19]
In order to better explore quantitative reconstructions of net primary productivity (NPP) conditions using a dinoflagellate cyst (dinocyst)-based transfer function method, we revised the tropical Atlantic modern dinocyst database n = 208 (Marret et al., 2008). Modern assemblages from the worldwide dinocyst atlas (Zonneveld et al., 2013) were added to provide a better geographical coverage of the South Atlantic Ocean. The environmental dataset was updated using the World Ocean Atlas 2013 for sea-surface temperature (SST) and sea-surface salinity (SSS) data, as well as for 1997-2017 mean NPP values recorded during SeaWifs and MODIS spatial programs. New environmental datasets were tested using anomalies regarding mean latitudinal SST as a potential index to track past upwelling activity. Finally, preindustrial NPP values, simulated with the IPSL-CM5A-LR model developed at the Institut Pierre Simon Laplace (IPSL) have been added to the dinocyst environmental database to provide NPP values consistent with the mean age of modern dinocyst assemblages. The transfer function method using the updated modern database was then applied to fossil dinocyst assemblages of core KZAI-01, retrieved off the Congo River mouth and covering the last 43.2 kyr. Our results indicate a dominant orbital forcing, with higher primary productivity values reconstructed during precession minima (MIS 3 and the last deglaciation) and enhanced by a maximum of obliquity during the last deglaciation and the Holocene. The synchronicity between high upwelling intensity and high terrigenous inputs during high NPP period (e.g. during the last Deglaciation) highlighted the prevalent role of river-induced upwelling activity, which is specific to the Congo River. These results have improved our understanding of the environmental forcing leading to major trophic changes in the intertropical area.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据