Temporal Changes in Biological Community Structure and Associated Geological Features at Newly-Formed Hydrothermal Vents on the EPR Crest

1991年4月发现的新形成的热液喷口位于东太平洋隆起(EPR)北纬9o45‘至9o52’之间的新近强烈火山活动区，这首次为我们提供了从一些深海热液喷口的表面“诞生”开始跟踪一段时间内生物和地质变化的机会。1992年3月，也就是在一次活跃的喷发事件发生11个月后，利用Alvin潜水器进行的观测和测量表明，自在该区域海底观察到喷发事件以来的11个月期间，地质特征、喷口流体地球化学和生物群落结构发生了巨大变化。在1992年3月的巡航中，210个标记物被部署在北纬9o49.61‘到9o50.36’之间的EPR轴向顶峰火山口(ASC)1.4公里处。由此产生的横断面横跨许多活跃的喷口区域，利用各种35 mm的电子静止相机和Hi-8视频功能进行了广泛的记录。这项研究的主要目标是记录三年期间沿大洋中脊轴线这一活跃部分观察到的生物群落结构和相关地质特征的时间变化。该方法包括：(1)沿着最近标记的1.4公里区域进行大量35毫米、Hi-8视频和电子静止相机(ESC)成像调查；(2)在ASC这一热液活动区内指定的三个“保护区”进行长期延时摄影(Hi-8视频)。

The discovery in April , 1991 of newly-formed hydrothermal vents located in areas of recent and intense volcanic activity between 9o45' and 9o52'N along the East Pacific Rise (EPR) affords, for the first time, the opportunity to follow biological and geological changes over time from the apparent "birth" of a number of deep-sea hydrothermal vents. Observations and measurements made using the submersible Alvin in March, 1992, 11 months after an active eruptive event, have indicated dramatic changes in geological features, vent fluid geochemistry and biological community structure over the 11-month period since the eruptive events was observed on the seafloor in the region. During the March, 1992 cruise, 210 markers were deployed along a 1.4 km stretch of the axial summit caldera (ASC) of the EPR between 9o49.61' and 9o50.36'N. The resulting transect, which traversed numerous active vent areas, was extensively documented utilizing a variety of 35 mm, electronic still camera, and Hi-8 video capabilities. The primary objective of this study is to document over a 3-year period temporal changes in biological community structure and associated geological features observed along this active segment of the mid-oceanic ridge axis. The approach involves a combination of: (1) numerous 35 mm, Hi-8 video, and electronic still camera (ESC) imaging surveys along the recently marked 1.4 km stretch of the ASC; and (2) long term time-lapse photography (Hi-8 video) at three-designated "sanctuaries" within this hydrothermally active region of the ASC.