Population and Community Dynamics of Corals: A Long Term Study

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，该研究已连续进行了30年，是对任何珊瑚礁进行的最长的此类研究；2)扩大研究范围，包括附近两个珊瑚礁的地点，以及在苍鹭礁的额外复制地点；3)从厘米到几十米的尺度上分析珊瑚和藻类的空间格局和动态，包括在斑块（受干扰打开）的殖民过程中，以及在大部分表面被许多群落拥挤之后。这些分析应该揭示相互作用的长期影响，这可能是决定自然群落结构的关键；4)通过有控制的现场实验来检验一些关于机制的假设：a)在内礁滩产生独特的珊瑚物种组成，b)在干扰后产生不同的藻类模式，c)精确地确定每个群落如何影响其邻居；5)建立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)表征时空动态；c)检验关于这些动态对群落后果的假设。这些模型还将用于评估群落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。实验方法，使用珊瑚移植和笼子来排除较大的食草动物，也曾在本研究中使用过，并得到了很好的证实。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招募的移植。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（热带和亚热带珊瑚礁上的主要无根生物）的自然群落如何在长时间内面对环境变化时组装和结构的一般认识；2)揭示了将环境与这些群落变化联系起来的一些机制，以及两者在短时间和长时间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（包括人类活动引起的环境变化）对这些自然群落的影响。

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.