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）的专性协会。科学家们对一种明显的压力反应-珊瑚漂白-产生了兴趣，这种反应涉及这种共生关系的“崩溃”，有时随之而来的是生态上毁灭性的珊瑚死亡。人们对珊瑚白化现象的兴趣是由于相信这些现象在世界范围内正在增加，以及它们作为环境变化的敏感生物指标的潜在价值。然而，我们对珊瑚白化的生态和原因的理解仍然存在很大差距。这些差距阻碍了将珊瑚白化与环境问题联系起来的努力。最近完成了对加勒比海主要的、研究最多的珊瑚Montastraea annularis和M. faveolata，揭示了一个与珊瑚漂白直接相关的根本误解。相反，早期，广泛接受的信念，珊瑚港只有一个共生体，这些珊瑚主机动态社区的三个类群的虫黄藻，主要是由梯度的环境辐照度。这种现象简单地解释了珊瑚漂白生态学中一个长期存在的问题-一种在珊瑚群落之间和内部都令人困惑的变异。因为它颠覆了几十年来研究珊瑚的基本前提，这一发现也为实验研究开辟了新的和意想不到的机会。本项目将分析Montastraea spp.的环境生物学。在多物种虫黄藻群落和环境压力的明确背景下。以前对这些群落的研究意味着与更好地研究的陆生植物群落相似。

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.