Collaborative Research: Eco-geomorphic coupling: Vegetation transition and sedimentary responses to faulting

该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。沿海湿地在海平面加速上升中生存的能力是一个极其重要和悬而未决的问题。沿海沼泽以互花米草为主，通过生态、地质和水文过程的组合垂直(共生)建造土地。美国墨西哥湾沿岸有许多生长断层，相对于其他沿海地区，那里的陆地表面可能会加速下沉或下沉。这些生长断层上的下沉速度的对比将对沼泽植被和相对海平面上升速度产生空间上可识别的影响。该项目的中心假设是互花米草湿地的淤积量和植被变化量与断层位移的量直接相关。该项目将集中在德克萨斯州马塔戈达湾的一个成熟的野外研究站，在那里，一个活跃的已知生长断层将互花米草沼泽一分为二。将利用实地调查、全球定位系统(GPS)、航空光探测和测距(激光雷达)数据集和潮汐计交叉参考对现场进行深入研究，以记录断层位移引起的持续海拔变化；岩石和生物地层学方法，结合古海平面估计，以及放射性碳(14-C)，以提供断层位移和海平面变化的历史和地质背景；棒状沉积物高程表(RSET)，以直接测量当代侵蚀和吸积速率；放射性核素尘(7-Be，137-Cs，210-Pb)，以提供关于沉积物积累和年代学的历史数据；以及遥感图像和实地植被清单，这将提供有关植物群落过渡的信息。该项目对管理渔业生产力、记录海岸侵蚀速度和制定沿海环境土地利用政策具有国家和全球影响。能够根据相对海平面波动确定沼泽下沉、淤积和/或侵蚀、沉积物供应和生态系统可持续性之间的当代和历史关系，这将有助于预测未来的变化和制定有效的适应战略。该项目将通过来自墨西哥湾沿岸地区的研究生、本科生和K-12学生的参与，整合研究、专业培训、公共宣传和教育。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The ability of coastal wetlands to survive accelerated sea level rise is a critically important and open question. Coastal marshes, which are dominated by the marsh grass Spartina alterniflora, build the land vertically (accrete) through a combination of ecological, geological and hydrological processes. The U.S. Gulf Coast has numerous growth faults, where the sinking or subsidence of the land surface can be accelerated relative to other coastal areas. Contrasts in the rate of subsidence across these growth faults will result in spatially-identifiable effects on marsh vegetation and on the rate of relative sea level rise. The central hypothesis of this project is that the amount of accretion and vegetative change of Spartina alterniflora wetlands is directly related to the amount of fault displacement. The project will be centered at an established field research station in Matagorda Bay, Texas, where an active, known growth fault bisects a Spartina alterniflora marsh. The field site will be intensively studied using field surveys, the Global Positioning System (GPS), aerial LIght Detection and Ranging (LIDAR) data sets, and tidal gauge cross-referencing to document ongoing elevation changes due to fault displacement; litho- and biostratigraphic methods, combined with paleo-sea level estimates, and radio-carbon (14-C) to provide a historical, geologic context for fault displacement and sea level change; Rod Sediment Elevation Tables (RSET) to directly measure contemporary rates of erosion and accretion; fallout radionuclides (7-Be, 137-Cs, 210-Pb) to provide historical data on sediment accumulation and chronology; and remote sensing imagery and field vegetative inventories, which will provide information on plant community transitions. This project has both national and global implications for managing the productivity of fisheries, documenting the rates of coastal erosion, and developing land-use policies in coastal environments. The ability to determine the contemporary and historical relationships between variable rates of marsh subsidence, accretion and/or erosion, sediment supply, and ecosystem sustainability in terms of relative sea level fluctuation will aid in projecting changes for the future and developing effective adaptation strategies. This project will integrate research, professional training, public outreach and education by the participation of graduate, undergraduate, and K-12 students from the Gulf Coast region.