Wetlands contribute anywhere from 50 to 80% of natural methane gas emissions to the atmosphere. Some global models suggest that wetland methane emissions could double by 2100, but saltwater inputs are simultaneously changing the coastal landscape, which could reduce methane contributions. Therefore, the goal of this project is to conduct an ecosystem-scale experiment that teases apart the mechanisms behind how saltwater inputs influence water chemistry, microbial communities, and methane dynamics over two years. This project maximizes taxpayer investment by leveraging an existing saltwater introduction experiment being conducted by the U.S. Fish and Wildlife Service aimed at reducing invasive plant species and enhancing endangered waterbird habitat. Hawai‘i Pacific University undergraduate classes will be actively involved in this project, so that the next generation of leaders can gain hands-on experience in environmental science. This project will also support the mentorship and independent research projects of at least three undergraduate students and two Master’s students. Students will participate in real-life natural resource management research including field work, laboratory techniques, data analysis, and technical writing, all of which promote educational growth, workforce development, and a strong economy. Brackish wetlands are characterized by lower methane emissions as salinity increases, which has been attributed to sulfate-reducing bacteria outcompeting meth