Carbon and Mineral Fluxes from Hydrothermal Plumes: Biogeochemical Linkages with the Upper Water Column

在Endeavor Ridge附近连续4年进行的生物声学调查显示，在1800至1900米深的热液羽流顶部上方的散射层中，非底栖浮游动物的浓度非常高。最令人兴奋的是强有力的证据表明，在羽流顶部上方50至100米厚的层中，浮游动物生物量增加了10至100倍。本研究项目将检验热液喷口对浮游动物生物量的垂直分布和组成有显著影响的假设，超出了喷口场和羽深的限制。该项目将使用声学传感器和摄影设备，结合同时进行的网拖(1)，以核实东北太平洋Juan de Fuca Ridge附近深水和中深水浮游动物散射层的分布和组成；(2)确定“海洋雪”的垂直分布和组成，并建立其与散射层的关系；(3)研究羽流深度上升物质通量的大小和特征。所得数据将根据热液喷口与深海和中深海水柱之间潜在的碳和矿物联系的动态进行评价。＊＊＊

9314591 Cowen Carbon and Mineral Fluxes from Hydrothermal Plumes: Biogeochemical Linkages with the Upper Water Column Bioaccoustical surveys conducted near Endeavor Ridge over four consecutive years have revealed intense non-benthic zooplankton concentrations in a scattering layer immediately above the top of the spreading hydrothermal plume at depths of 1800 to 1900 m. Most exciting was the strong evidence for a 10 to 100 fold increase in zooplankton biomass in a 50 to 100 m thick layer immediately above the top of plume. This research project will examine the hypothesis that hydrothermal venting markedly influences the vertical distribution and composition of the zooplankton biomass beyond the limits of the vent field and plume depths. The project will use acoustic sensors and photographic equipment in combination with simultaneous net tows (1) to verify the distribution and composition of deep and mid-depth zooplankton scattering layers in the vicinity of Juan de Fuca Ridge in the North east Pacific; (2) determine the vertical distribution and composition of "marine snow" and establish its relation to the scattering layers; and (3) to investigate the magnitude and characteristics of ascending material fluxes from the plume depths. The resulting data will be evaluated with respect to the dynamics of potential carbon and mineral linkages between hydrothermal venting and the deep and mid-depth ocean water column. ***