RAPID: Dissolved carbon transport and CO2 outgassing under an unprecedented long-lasting flood of the Mississippi-Atchafalaya River System

密西西比河正在经历持续时间最长的连续几天的洪水。在洪水期间，大量的碳可以在河流中运输。河流中的碳可以是颗粒的形式，也可以溶解在水中。碳也可以从河流释放到大气中。这个项目调查了在长期的洪水期间，密西西比河中有多少碳被运输或释放。河流中的碳影响水生物种和水质。该项目的成果增加了对洪水对大河流碳动态影响的了解。本科生和研究生参与采样，对气候变化对河流碳迁移转化的影响知之甚少。该项目利用了一个独特的、意想不到的机会，将密西西比河的长期洪水与碳通量和运输的测量结合起来。该项目密集测量地表水中溶解二氧化碳、溶解有机碳和溶解无机碳的分压。这些测量被用来量化这条大河在所有汛期的总溶解碳和二氧化碳通量。这些结果被用来检验关于河流流态的变化如何影响流中碳动态的假设。本科生和研究生在该项目期间接受现场采样和数据分析方面的培训。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The Mississippi River is experiencing the longest, consecutive days of flooding. During floods, large amounts of carbon can be transported in rivers. Carbon in rivers can be in the form of particles or dissolved in the water. The carbon can also be released to the atmosphere from the river. This project investigates how much carbon is transported or released in the Mississippi River during prolonged flooding. The carbon in rivers impacts aquatic species and water quality. The results of this project increase the understanding of the impact of floods on carbon dynamics in large rivers. Undergraduate and graduate students participate in sampling the water.The knowledge of the effect of climate change on river carbon transport and transformation is limited. This project takes advantage of a unique and unanticipated opportunity to couple prolonged flooding of the Mississippi River with measurements of carbon flux and transport. The project intensively measures the partial pressure of dissolved carbon dioxide, dissolved organic carbon, and dissolved inorganic carbon in the surface water. These measurements are used to quantify the total dissolved carbon and carbon dioxide flux from this large river during all flood stages. The results are used to test hypotheses regarding how changes in river flow regime may impact in-stream carbon dynamics. Undergraduate and graduate students receive training in field sampling and data analysis during this project.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.