Collaborative Research: Fate of Coastal Wetland Carbon Under Increasing Sea Level Rise: Using the Subsiding Louisiana Coast as a Proxy for Future World-Wide Sea Level Projections

合作研究：海平面上升加剧下沿海湿地碳的命运：利用路易斯安那海岸下沉作为未来全球海平面预测的代理

• 批准号: 1636052
• 负责人: John White
• 金额: $ 24.99万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1636052&HistoricalAwards=false
• 关键词: Collaborative; Research; Fate; Coastal; Wetland

Coastal Louisiana is currently experiencing net sea level rise at rates higher than most of the world's coastlines and within the global range predicted to occur in the next 65 - 85 years, making Louisiana an ideal site to study potential future impacts of rising sea level on coastal systems. This project will use field collection and controlled tank experiments to study the changing organic carbon cycle resulting from erosion of marsh soils along with its impact on associated biogeochemical processes. The hypothesis tested in this study is that the majority of eroded soil organic carbon is converted to carbon dioxide (CO2) and released to the atmosphere, representing an addition to the anthropogenic input of CO2. This process has not been quantified and could be an important missing component in predictive models of atmospheric CO2 changes. While this process may be of only regional importance today in comparison to other sources of CO2, this study of the Louisiana coast will greatly enhance our full understanding of the potential impacts on the global carbon cycle that may result from coastal erosion as global sea level continues to rise.The project will train graduate and undergraduate students in interdisciplinary research involving marine and wetland biogeochemistry, microbiology, and ecological modeling. It will also fund development of an interactive, educational display on the loss of coastal wetlands for the Louisiana Sea Grant's annual Ocean Commotion educational event attended by area middle and high school students, teachers, and parents. Results from this study may also inform community planners both regionally and worldwide as they prepare for sea level rise in coastal communities.Eustatic sea level rise and regional subsidence have created a much greater rate of coastline loss in Louisiana than is being experienced in most of the world's coastal regions, reaching global rates that are predicted to occur worldwide in 65 - 85 years. This provides a unique potential to extrapolate data from Louisiana's changing coastal carbon cycle to both regional and global models of the future impact of sea level rise and coastal erosion. By quantifying and modeling the importance of CO2 emissions resulting directly from mineralized soil organic matter from eroding coastlines, a missing element can be added to climate change models. The PIs here plan to investigate the fate of the coastal wetland carbon pool as it erodes using field sampling, laboratory analysis, mesocosm manipulations, and the creation of a coupled physical-biogeochemical model for the basin being studied. Beyond quantifying increased CO2 emission, the PIs will also address the potential for increased eutrophication due to input of nutrients from eroded soils, as well as the potential for future contribution to existing hypoxic zones in the northern Gulf of Mexico that result from excessive nutrient input from the Mississippi River watershed.

目前，路易斯安那州沿海地区的净海平面增长率高于大多数世界海岸线，并且在未来65 - 85年内发生的全球范围内，这使路易斯安那州成为研究海平面对海岸系统上升的未来影响的理想场所。该项目将使用现场收集和受控的储罐实验来研究因沼泽土壤侵蚀而导致的有机碳循环的变化，以及其对相关生物地球化学过程的影响。在这项研究中检验的假设是，大多数侵蚀的土壤有机碳转化为二氧化碳（CO2）并释放到大气中，代表了CO2的人为输入的增加。该过程尚未量化，并且可能是大气二氧化碳变化的预测模型中的重要缺失组成部分。尽管与CO2的其他来源相比，今天的这一过程可能仅是区域重要性，但对路易斯安那州沿海的这项研究将大大增强我们对随着全球海平面沿海侵蚀可能导致的全球碳周期影响的全面理解，随着全球海平面的侵蚀可能会持续上升。它还将资助有关路易斯安那州年度海洋骚扰的沿海湿地丧失的互动，教育展示，由地区中学生和高中生，老师和父母参加。这项研究的结果还可以为社区规划者在全球范围内为沿海社区的海平面上升而在全球范围内为社区规划师提供通知。自顾性的海平面上升和区域沉降在路易斯安那州的海岸线损失率比世界上大多数沿海地区所经历的要达到的全球率更高，预计将在65 - 85年中全球发生。这为从路易斯安那州不断变化的沿海碳循环推断出数据的数据提供了独特的潜力，以推导出海平面上升和沿海侵蚀的未来影响的区域和全球模型。通过量化和建模直接由侵蚀海岸线矿化土壤有机物产生的二氧化碳排放的重要性，可以将缺失的元素添加到气候变化模型中。这里的PI计划在使用现场采样，实验室分析，中验操作以及创建研究盆地的耦合物理生物地球化学模型时，调查了沿海湿地碳池的命运。除了量化二氧化碳排放量的增加外，PI还将解决由于侵蚀土壤中养分的输入而增加富营养化的可能性，以及对墨西哥北部现有低氧区域的未来贡献的潜力，这是由于密西西比河水从密西西比河水中过量投入的过量养分所致。

项目成果

The denitrification potential of eroding wetlands in Barataria Bay, LA, USA: Implications for river reconnection

美国路易斯安那州巴拉塔里亚湾侵蚀湿地的反硝化潜力：对河流重新连接的影响

• DOI: 10.1016/j.scitotenv.2019.05.475
• 发表时间: 2019
• 期刊: Science of The Total Environment
• 影响因子: 9.8
• 作者: Vaccare, Jessica;Meselhe, Ehab;White, John R.
• 通讯作者: White, John R.

A numerical investigation of salinity variations in the Barataria Estuary, Louisiana in connection with the Mississippi River and restoration activities

对路易斯安那州巴拉塔里亚河口与密西西比河和恢复活动相关的盐度变化进行数值调查

• DOI: 10.1016/j.ecss.2020.107021
• 发表时间: 2020
• 期刊: Coastal and Shelf Science
• 作者: Ou, Yanda;Xue, Z. George;Li, Chunyan;Xu, Kehui;White, John R.;Bentley, Samuel J.;Zang, Zhengchen
• 通讯作者: Zang, Zhengchen

Understanding the fate of soil organic matter in submerging coastal wetland soils: A microcosm approach

了解淹没沿海湿地土壤中土壤有机质的命运：微观方法

• DOI: 10.1016/j.geoderma.2018.08.020
• 发表时间: 2018
• 期刊: Geoderma
• 影响因子: 6.1
• 作者: Steinmuller, Havalend E.;Dittmer, Kyle M.;White, John R.;Chambers, Lisa G.
• 通讯作者: Chambers, Lisa G.

Long-term fate of rapidly eroding carbon stock soil profiles in coastal wetlands

• DOI: 10.1016/j.scitotenv.2020.141913
• 发表时间: 2021-01-20
• 期刊: SCIENCE OF THE TOTAL ENVIRONMENT
• 影响因子: 9.8
• 作者: Sapkota, Yadav;White, John R.
• 通讯作者: White, John R.

A Two Decadal (1993–2012) Numerical Assessment of Sediment Dynamics in the Northern Gulf of Mexico

墨西哥湾北部沉积物动力学的两个十年（1993 年至 2012 年）数值评估

• DOI: 10.3390/w11050938
• 发表时间: 2019
• 期刊: Water
• 影响因子: 3.4
• 作者: Zang, Zhengchen;Xue, Z. George;Xu, Kehui;Bentley, Samuel J.;Chen, Qin;D’Sa, Eurico J.;Ge, Qian
• 通讯作者: Ge, Qian