Developing a Regional Context for Rocky Subtidal Communities: Upwelling, Biotic Interactions and Diversity Regulation in the Galapagos Marine Reserve

群落生态学的基础是在相对较小的空间尺度上进行的研究。在海洋生态学中，基础的组成部分是分析受洋流影响的焦点地点的物种相互作用，洋流运送营养物、食物和下一代生物的生殖繁殖体。因此，在较大的空间尺度上，海洋学过程在一定程度上将生活在当地的群落联系在一起。了解这种联系的程度和规模是必不可少的社区生态学的增长，作为一种智力的努力，也为预测当地的生物群沿海海洋生态系统将被修改的全球变化的步伐越来越快。后一种情况之所以适用，是因为全球大气过程调节着耦合当地地点的洋流。尽管近二十年来人们已认识到需要扩大海洋研究的空间范围，但在海洋底栖生态学、特别是潮下带生态系统方面发展区域海洋学观点的进展缓慢，本项目通过为生活在岛屿陡峭水下一侧的底栖群落发展区域背景，与这些更广泛的目标有关在世界第二大海洋保护区-加拉帕戈斯海洋保护区（GMR）内的岩石墙（Bustamente et al 2000）。由于营养上升流和海洋食物网几乎是完整的，GMR潮下带生态系统提供了一个很好的机会，调查底部的重要性？上（即由食物资源驱动）与上？向下（掠夺性）调节底栖生物群落。项目小组的初步研究表明，在水流以迄今为止报告的最高上升速度（60厘米/秒）沿岩壁向上流动的地方，群落变化的速度特别快。一个实验设计是用来测试的一般假设，底部？向上和顶部？岩石壁群落的向下控制作为上升流的函数可预测地变化。定期测量的涌升流，叶绿素a，营养和浮游动物的浓度在中央GMR的8个站点将被放置在一个更大的背景下，通过比较，每日高分辨率的图像叶绿素a提供的新的SeaWIFS设施在查尔斯达尔文研究站。测量藻类积累的治疗保护和接触食草动物将评估底栖藻类的反应，可能增强上升流营养制度。因为地表动物。无脊椎动物的浮游生物的链接水柱生产更高的营养级，实验提出了测量的增长和招聘的5 epifaunal物种和他们的消费者（蜗牛，海胆），以测试自下而上和顶部的预测？下行链路关键的捕食者将被封闭，以评估的假设，物种之间的相互作用的强度是最大的上升流网站，而摄像机将提供另一种衡量消费者压力的网站变化。最后，理论和观察表明，最高的多样性和营业额的多样性发生在上升流的网站，由于快速的无脊椎动物生产和高捕食的主要空间占用者。通过在社区生态学，海洋学和保护生物学的十字路口工作，该研究将增加我们对物种相互作用中的生产力和局部变化如何影响海洋保护区物种多样性的理解。该提案更广泛的优点是，它将直接有助于保护规划，培养博士生，并对本科生和研究生教学产生积极影响。

The foundation of community ecology has been constructed from studies conducted on relatively small spatial scales. In marine ecology, the building blocks of the foundation are analyses of species interactions at focal sites that are bathed by currents transporting nutrients, food and reproductive propagules of the next generation of organisms. Thus, the communities living at local sites are linked to some extent on larger spatial scales by oceanographic processes. Understanding the extent and scale of such linkages is essential for the growth of community ecology as an intellectual endeavor and also for predicting how local biota of coastal marine ecosystems will be modified by an increasing pace of global change. The latter situation applies because global atmospheric processes regulate the oceanic currents that couple local sites. Although the need to expand the spatial scale of marine research has been recognized for nearly two decades, progress in developing a regional oceanographic perspective in marine benthic ecology has been slow, particularly for sub-tidal ecosystems.This project herein relates to these broader goals by developing a regional context for benthic communities living on steep underwater sides of islands (rock walls) in the Galapagos Marine Reserve, (GMR) the second largest marine protected area in the world (Bustamente et al 2000). Due to nutritive upwelling currents and marine food webs that are nearly intact, GMR subtidal ecosystems provide an excellent opportunity to investigate the importance of bottom ?up (i.e. driven by food resources) vs top?down (predatory) regulation of benthic communities. Preliminary research by the project team indicates that the pace of community change is especially rapid where currents flow up rock walls at some of highest upwelling velocities reported (to 60 cm s) to date. An experimental design is used to test the general hypothesis that bottom? up and top ?down control of rock wall communities varies predictably as a function of upwelling. Regular measurement of upwelling currents, chlorophyll a, nutrient and zooplankton concentrations at 8 sites in the central GMR will be placed in a larger context by comparison to daily, high resolution images of chl a provided by the new SeaWIFS facility at the Charles Darwin Research Station. Measuring algal accumulation in treatments protected from and exposed to grazers will assess a response of benthic algae to the potentially enhanced upwelling nutrient regime. Because epifaunal. invertebrates feeding on plankton link water column production to higher trophic levels,, experiments are proposed to measure the growth and recruitment of 5 epifaunal species and their consumers (snails, sea urchins) to test the predictions of bottomup and top?down linkage . Key predators will be enclosed to evaluate the hypothesis that the strength of species interactions is greatest at upwelling sites while video cameras will provide another measure of site variation in consumer pressure. Finally, theory and observation suggest that the highest diversity and turnover of diversity occurs at upwelling sites due to rapid invertebrate production and high predation on primary space occupiers. By working at the crossroads of community ecology, oceanography and conservation biology, the research will increase our understanding of how productivity and local variation in species interactions influence species diversity in marine reserves. The broader merits of the proposal are that it will directly contribute to conservation planning, train a PhD student and positively impact undergraduate and graduate teaching.