Benthos of the Cariaco Basin: Is the Eukaryotic Community Similar to that of the Santa Barbara Basin?

Cariaco盆地的底栖生物：真核生物群落与圣巴巴拉盆地相似吗？Cariaco盆地是地球上已知的第二大缺氧水体，人们对其水柱过程和沉积记录进行了广泛研究，但对该盆地缺氧缺氧区的底栖生物几乎一无所知。一个丰富的后生动物和原生生物群落已被描述从沉积缺氧-好氧界面在圣巴巴拉盆地，这项研究将探讨的可能性，Cariaco盆地支持一个同样丰富的底栖财团。拟议项目的广泛目标是描述Cariaco盆地的真核底栖生物。 我们将：1）使用Percoll梯度提取和荧光染色对真核生物群落进行定量; 2）使用DAPI染色和超微结构检查来检查真核生物的原核伴生物; 3）使用各种活力指标（即，荧光探针、超微结构、常规孟加拉玫瑰红染色）; 4）确定缺氧/好氧界面底栖有孔虫群落组成的变化。2001年5月，将利用委内瑞拉“Hermano Gines”号考察船对Cariaco盆地进行一次短途考察所收集的材料来实现这些具体目标。将在东北部的8个地点、东部次盆地的一个地点和两个次盆地之间的鞍状区域的一个地点采集重复的多岩心。将采用微温克勒分析法测定底层水的氧浓度。研究结果将影响到海底生态学、生物多样性和海洋学以及古海洋学等领域。如果发现新的共生体或对这种极端环境的适应，细胞生物学和进化生物学也可能受益。

Benthos of the Cariaco Basin:Is the Eukaryotic Community Similar to that of the Santa Barbara Basin?The Cariaco Basin, the second largest known anoxic body of water known on Earth, has been extensively studied for its water-column processes and sedimentary record, but virtually nothing is known about the benthos of the oxygen-depleted and anoxic regions of the basin. An abundant community of metazoans and protists has been described from the sedimentary anoxic-oxic interface in the Santa Barbara Basin, and this study will examine the possibility that the Cariaco Basin supports a similarly rich benthic consortium. The broad objective of the proposed project is to describe the eukaryotic benthos of the Cariaco Basin. We will: 1) quantify the eukaryotic community using Percoll gradient extraction and fluorogenic staining; 2) examine the eukaryotes for prokaryotic associates using DAPI staining and ultrastructural examination; 3) identify the benthic foraminiferal assemblage using various viability indicators (i.e., fluorogenic probes, ultrastructure, conventional rose Bengal staining); and 4) determine changes in the benthic foraminiferal community composition across the anoxic / oxic interface. These specific aims will be addressed using material collected on one short cruise to sample the Cariaco Basin using the Venezuelan ship RV Hermano Gines in May 2001. Replicate multicores will be taken at each of 8 sites in the northeastern sector, at one site located in the eastern sub-basin, and at one site on the saddle between the two sub-basins. Bottom-water oxygen concentrations will be determined with microwinkler analysis. Results will impact the areas of benthic ecology, biodiversity and biogeography, and paleoceanography. Cell biology and evolutionary biology may also benefit if novel symbioses or adaptations to this extreme environment are identified.