SGER - Sampling the Recent 100-year Flood Event in SE Arkansas

阿肯色州东南部在2008年春天经历了一场所谓的百年一遇的洪水。人们对这一地区这种洪水的历史起源和频率知之甚少。可追溯到前人类时代的洪泛区湖泊沉积物可能为理解人类与自然气候变化在洪水中所起的作用提供了线索。2008年的洪水为研究现代洪水沉积层提供了一个独特的机会。参与该项目的科学家将对怀特河野生动物保护区牛弓湖表层沉积物岩心的横断面进行采样，以确定沉积物颗粒的尺寸分布。这些岩心将使用铅的同位素进行测年。此外，研究人员将能够从岩芯中确定水化学和硅藻组合随时间的变化。这项研究将使洪水层的识别和年代测定成为可能，并由此重建密西西比河谷下游的长期洪水历史。从历史上看，洪水是一种自然灾害，对低收入家庭的影响不成比例。更好地了解洪水的长期动态可能有助于改善城市规划，减少未来的洪水破坏。实地调查将为来自印度和美国的两名女研究生提供经验。

Southeastern Arkansas experienced a so-called 100-year flood in spring of 2008. The historic origin and frequency of such flooding in this region is poorly understood. Floodplain lake sediments extending back to pre-human times may hold clues for understanding the role of humans versus natural climatic variability in flooding. The 2008 flood provides a unique opportunity to study a modern flood sediment layer. Scientists in this project will sample a transect of surface sediment cores of oxbow lakes in the White River Wildlife Refuge in order to determine size distribution of sediment grains. The cores will be dated using an isotope of lead. In addition, the investigators will be able to determine changes in water chemistry and diatom assemblages over time from the cores. This study will enable identification and dating of flood layersand from them reconstruction of a long term flood history for the lower Mississippi valley. Historically, flooding was a natural disaster that disproportionately impacted low income families. A better understanding of long term flood dynamics may be useful in improving urban planning and reducing flood damage in the future. The fieldwork will provide experience for two female graduate students from India and the U.S.