Population and Community Dynamics of Corals: A Long Term Study

9321892康奈尔本项目的目标有几个：1）扩大对澳大利亚大堡礁珊瑚和藻类生态群落的详细长期监测，该监测在过去30年中一直在持续进行，这是对任何珊瑚礁进行的时间最长的此类研究; 2）扩大研究范围，包括附近两个珊瑚礁的地点，以及Heron Reef的其他重复地点; 3）分析珊瑚和藻类在几个尺度上的空间格局和动态，从厘米到几十米，在斑块的定殖过程中（通过扰动打开）和在大部分表面已经被许多菌落拥挤之后。这些分析应揭示相互作用的长期影响，这可能对确定自然群落的结构至关重要; 4）用受控的实地实验来测试一些关于机制的假设：a）在内礁滩产生珊瑚的独特物种组成，B）在干扰后导致藻类的对比模式，以及c）精确确定每个殖民地如何影响其邻居; 5）建立这些珊瑚和藻类种群和群落动态的数学模型和计算机模拟：a）调查过去和现在的条件对未来变化的影响，B）描述时间和空间动态，以及c）检验关于这些动态对群落的后果的假设。这些模型还将用于评估社区结构和动态可能或可能不受空间关系细节影响的程度。实地方法将使用过去30年来使用的标准抽样技术，以确保长期数据库的连续性。采用珊瑚移植和笼子排除大型食草动物的实验方法在本研究之前也曾使用过，并且行之有效。在大堡礁的其他地方，合作研究人员已经成功地进行了幼虫选择实验和新兵移植。这项研究对知识进步的意义在于：1）它加深了对珊瑚和藻类的自然群落如何（热带和亚热带珊瑚礁上占优势的固着生物），在面对长期环境变化时进行组合和结构化;（2）揭示了环境与这些群落变化之间的某些联系机制，以及两者在短期和长期以及小空间尺度和大空间尺度之间的变化;（3）有助于预测环境变化对这些自然群落的影响，包括人类活动引起的环境变化。

9321892 Connell The objectives of the present project are several: 1) To extend the detailed long-term monitoring of ecological communities of corals and algae on the Great Barrier Reef, Australia which has been carried on continuously over the past 30 years, the longest such study on any coral reef; 2) to expand the study to include sites on two nearby reefs, and additional replicate sites on Heron Reef; 3) to analyze spatial patterns and dynamics of corals and algae at several scales, from centimeters to tens of meters, both during the course of colonization of patches (opened by disturbances) and after most of the surface has become crowded by many colonies. These analyses should reveal the long-term effects of interactions that may be crucial in determining how natural communities are structured; 4) to test with controlled field experiments some hypotheses about mechanisms: a) that produce the unique species composition of corals at the Inner Reef Flat site, b) that cause contrasting patterns of algae after disturbances, and c) that determine precisely how each colony affects its neighbors; 5) to build mathematical models and computer simulations of the dynamics of these populations and communities of corals and algae: a) to investigate the influence of past and present conditions on future changes, b) to characterize temporal and spatial dynamics, and c) to test hypotheses about the consequences of these dynamics to the community. The models will be also used to asses the degree to which community structure and dynamics may or may not be influenced by details of spatial relationships. The field methods will use the standard sampling techniques used over the past 30 years, to assure continuity in the long-term data base. The experimental methods, using coral transplanting and cages to exclude larger herbivores, have also been used before in this study and are well- established. Larval choice experiments and new recruit t ransplants have been carried out successfully by the co- investigators elsewhere on the Great Barrier Reef. The significance of this proposed research to the advancement of knowledge is that: 1) it deepens the general knowledge of how natural communities of corals and algae (the dominant sessile organisms on tropical and sub-tropical reefs), are assembled and structured in the face of changes in their environment over extended periods of time; 2) it reveals some of the mechanisms that link the environment with these community changes, and how both vary over short and long time periods and between small and larger spatial scales; and 3) it helps to predict the effect of environmental changes, including those caused by human activity, on these natural communities.