Collaborative Research: Particulate Organic Carbon Fluxes and Sediment Accumulation in the Cariaco Basin

Cariaco盆地是委内瑞拉大陆架上的一个1,400米深的凹陷，其中缺氧沃茨覆盖着有机质含量高（1-5重量%）的层状沉积物。这些纹层是由初级生产力的季节性变化和沿着加勒比海南部的陆源沉积物输入造成的，包含了热带大西洋过去气候变化的高分辨率记录。在这项合作努力中，南佛罗里达大学（USF）、南卡罗来纳州大学（USC）和纽约州立大学（SUNY）的研究人员寻求将水文、初级生产力、水柱微生物活性、垂直颗粒通量、将卡里亚科盆地的沉积物累积速率测量结果综合起来，以了解当代沉积模式如何反映这种气候和海洋变化。 中心目标是了解的因素，控制初级生产和颗粒的垂直通量之间的关系在Cariaco盆地。该项目将继续目前的时间序列的每月观测10'30' N，64'40' W，开始于1995年11月，根据CARIACO（碳保留在彩色海洋）计划。这包括继续部署带有四个沉积物收集器（275、350、450和1，200米）的系泊设备，以便在每个深度每两周进行一次样品采集。作为捕集器的补充，将有一个系泊装置，配有两个声学多普勒海流剖面仪（ADCP），一个向上看，另一个从大约250米的深度向下看，以测量从岩床深度以下到水面的海流，为期三年。 每年，将在CARIACO站和盆地外11'40' N，64'40' W之间进行一次样带，以帮助了解侵入和上升流所涉及的源水特征。将利用当地和遥感数据对区域风和海平面进行研究，以确定是否主要通过当地或环流尺度的过程来强迫上升流。 将收集和分析Cariaco盆地的沉积物，以重建Cariaco盆地过去世纪的海洋学状况，并为更长期的古海洋学研究提供一个窗口。该计划意义重大，因为它提供了正确解释Cariaco沉积物中记录的过去气候变化所需的地面实况。

ABSTRACTOCE-0118349The Cariaco Basin is a 1,400-m deep depression on the continental shelf off Venezuela in which anoxic waters cover laminated sediments with high organic matter content (1-5 wt%). These laminae, which result from seasonal variations in primary productivity and terrigenous sediment input along the southern the Caribbean Sea, contain a high-resolution record of past climate change in the tropical Atlantic Ocean. In this collaborative effort, researchers at the University of South Florida (USF), the University of South Carolina (USC), and the State University of New York (SUNY) seek to integrate hydrographic, primary productivity, water column microbial activity, vertical particulate flux, and sediment accumulation rate measurements in the Cariaco Basin into a synthesis to understand how contemporary sedimentation patterns reflect this climatic and oceanographic variability. The central objective is to understand the factors that control the relationship between primary production and the vertical flux of particles in the Cariaco Basin. This project will continue the current time series of monthly observations at 10'30' N, 64'40' W that began in November, 1995, under the CARIACO (CArbon Retention In A Colored Ocean) Program. This includes continuing deployment of a mooring with four sediment traps (275, 350, 450, and 1,200 m) to provide bi-weekly sample collections at each depth. Complementing the traps will be a mooring with two Acoustic Doppler Current Profilers (ADCP), one looking up and the other looking down from a depth of about 250 m, to measure currents from below the sill depth to the surface for a three-year period. Each year, one transect will be conducted between the CARIACO station and 11'40' N, 64'40' W outside the basin, to help understand the characteristics of source water involved in intrusions and upwelling. Regional wind and sea level will be examined using both local and remotely-sensed data to establish whether forcing for upwelling occurs primarily through local or gyre-scale processes. Sediments from the Cariaco basin will be collected and analyzed to reconstruct the oceanographic condition in the Cariaco Basin over the past century and provide a window for longer-scale paleoceanographic studies. The program is significant because it provides groundtruthing needed for proper interpretation of past climate changes recorded in the Cariaco sediments.