RUI: Experimental Studies on Multi-Species Zooxanthella Communities and Coral Bleaching

造礁珊瑚是异养动物和光养甲藻内共生体(虫黄藻)的专性组合。科学家们开始对一种明显的压力反应--珊瑚白化--感兴趣，这种反应涉及这种共生关系的“破坏”，偶尔会导致珊瑚在生态上造成毁灭性的死亡。人们对珊瑚白化的兴趣源于这样一种信念，即这些事件在全世界范围内都在增加，而且它们作为环境变化的敏感生物指标的潜在价值。然而，我们对珊瑚漂白的生态学和原因的理解仍然存在很大差距。这些差距挫败了将珊瑚漂白与环境问题联系起来的尝试。最近完成的对加勒比海主要和研究最多的珊瑚--环带珊瑚和褐珊瑚的研究揭示了一个与珊瑚漂白直接相关的根本性误解。与早先被广泛接受的珊瑚只有一个共生体的看法相反，这些珊瑚拥有三个虫黄藻类的动态群落，这些群落主要由环境辐射的梯度组成。这一现象简单地解释了珊瑚漂白生态学中的一个长期问题--在珊瑚群体之间和珊瑚群体内部，这是一种令人困惑的变异。因为它颠覆了珊瑚研究了几十年的基本前提，这一发现也为实验研究打开了新的意想不到的机会。该项目将分析Montastraea spp.的环境生物学。在多物种虫草群落和环境胁迫的显性背景下。以前对这些群落的研究表明，这些群落与研究得更好的陆地植物群落有相似之处。

Reef-building corals are obligate associations of heterotrophic animals and phototrophic dinoflagellate endosymbionts (zooxanthellae). Scientists have become interested in a conspicuous stress response -- coral bleaching -- that involves the `breakdown` of this symbiosis, occasionally followed by ecologically devastating coral mortality. Interest in coral bleaching is motivated by the belief that these events are increasing world-wide, and by their potential value as a sensitive bioindicator of environmental change. However, large gaps in our understanding of both the ecology and causes of coral bleaching remain. These gaps frustrate attempts to relate coral bleaching to environmental issues. Recently completed studies on the Caribbean's dominant and most studied corals, Montastraea annularis and M. faveolata, revealed a fundamental misunderstanding that relates directly to coral bleaching. Contrary to the earlier, widely accepted belief that corals harbor only one symbiont, these corals host dynamic communities of three taxa of zooxanthellae that are primarily organized by gradients of ambient irradiance. This phenomenon explained a longstanding issue in coral bleaching ecology -- an otherwise bewildering variation, both among and within coral colonies -- in simple terms. Because it upsets a basic premise on which corals have been studied for decades, this discovery also opens up new and unexpected opportunities for experimental research. This project will analyze the environmental biology of Montastraea spp. in the explicit contexts of multi-species zooxanthella communities and environmental stress. Previous studies of these communities imply parallels with much better studied communities of terrestrial plants.