SGER: Examining the Impact of Land-Use on Offshore Sediment Transport and Reef Degradation during a Category Five Hurricane on a Mountainous Caribbean Island: Roatan, Honduras

虽然人们普遍认识到开发可能会对近岸珊瑚礁生态系统产生各种负面影响，但研究人员很难将具体的土地使用做法直接与物理环境的变化联系起来，最终与珊瑚礁退化联系起来。该项目将使用以前收集的物理和生物数据，结合米奇飓风(该地区本世纪最大的风暴)之后收集的新数据，研究各种土地利用做法如何影响加勒比发展中的多山海岸线的沿海风暴过程。罗坦岛是海湾群岛中最大的一个，海湾群岛是距离洪都拉斯北海岸约60公里的一系列岛屿。海湾群岛是伯利兹珊瑚礁系统的一部分，伯利兹珊瑚礁系统是全球第二长的珊瑚礁区域。为了应对日益发展的确定性，1998年夏天启动了一项长期监测方案。该项目涉及对沉积物积累、沉积物空间分布、陆源沉积物输入、活珊瑚百分比、水质和粪便大肠菌群的监测。Roatan是一个多山的岛屿，可以分为不同的分水岭，具有不同的近岸生态系统，沿海岸几乎没有明显的沉积物交换或其他物理特征。这为研究特定土地使用做法对近海物理参数的影响，并最终对珊瑚礁的影响提供了一个自然的环境。监测站被放置在监测不同类型土地利用、不同排水和不同人类影响的分水岭近海情况。例如，在一个陡峭的分水岭的近海，几乎没有开发，但它已经被清理出来，供放牧牲畜使用。有一个类似的分水岭近海正在被细分和开发，还有一个近海类似的排水系统的控制点，那里根本没有人类的影响。我们希望能够直接将特定的土地利用做法与风暴引发的近海物理参数变化联系起来，然后评估对珊瑚死亡的任何影响。由于基线数据是在飓风发生前不久收集的，而且在选址和风暴通过之间没有其他事件，因此应该有很好的风暴造成损失的记录。这项研究将提供第一个很好的近似值，即不同的土地利用对珊瑚死亡的相对影响，以应对一个大的热带系统的通过。收集的数据将具有重要的科学和管理价值。

Young OCE 9903922Although there has been a general understanding that development may have a variety of negative impacts on nearshore reef ecosystems, researchers have had difficulty tying specific land use practices directly to changes in the physical environment, and ultimately to reef degradation. This project will use previously collected physical and biological data, combined with new data collected after Hurricane Mitch (the largest storm in the region this century) to examine how various land use practices impact coastal storm processes along a developing, mountainous Caribbean shoreline. The island of Roatan is the largest of the Bay Islands, a chain of islands roughly 60 km off the north coast of Honduras. The Bay Islands are a part of the Belize Reef System, the second longest coral reef tract on the globe. In response to the certainty of increased development, a long-term monitoring program was initiated in the summer of 1998. This program involves the monitoring of sediment accumulation, sediment spatial distribution, terrigenous sediment input, percent live coral, water quality, and fecal coliform bacteria. Roatan is a mountainous island that can be divided into distinct watersheds with distinct nearshore ecosystems that have little apparent exchange along shore of sediment or other physical characteristics. This provides a natural setting to study the impacts of particular land-use practices on offshore physical parameters, and ultimately on the reef. Monitoring stations were placed to monitor conditions immediately offshore of watersheds with varying types of land use, varying drainage, and varying human impact. For example, there is a site offshore of a steep watershed that has little development, but it has been cleared for grazing cattle. There is a site offshore of a similar watershed that is being subdivided and developed and a control site offshore of a similar drainage where there has been no human impact at all. We hope to be able to directly tie particular land-use practices to storm-induced changes in offshore physical parameters, and then assess any impact to coral mortality. Because baseline data were collected so soon before the hurricane, and there were no other events between site placement and the storm's passage, there should be an excellent record of storm-caused damage. This study will provide the first good approximation of the relative impact of varying land use on coral mortality in response to the passage of a large tropical system. The data gathered will be of important scientific and management interest.