Microbes are often ignored in environmental research and education. This gap hinders scientists' ability to predict how ecosystems will respond to anthropogenic disturbances such as nutrient inputs, land-use changes, and global warming. A CAREER grant has been awarded to Dr. Jennifer Hughes of Brown University to pursue activities that incorporate microbial diversity science into environmental education, and to investigate how much the composition of bacterial assemblages in the environment matters to the way an ecosystem "works" - for example, how it cycles nutrients and decomposes wastes. There are many hurdles to answering this research question. For instance, little is known about how the composition of bacterial communities varies within and across similar habitat types in different regions of the planet, making it difficult to decide how to sample bacterial communities, let alone study how they affect the environment. In addition, there are few methods developed to conduct experiments on bacterial communities directly in the field. To address these challenges, Dr. Hughes will combine molecular methods such as DNA sequencing with traditional ecological field experiments. She will first document patterns of bacterial diversity across salt marshes on three continents. She will then use this information to test how bacterial communities respond to disturbances such as nitrogen deposition and whether changes in bacterial composition translate into changes in ecosystem processes.
This project will be conducted in coastal marshes, an ecosystem that is literally and figuratively at the boundary of a variety of environmental, social, and political problems. Perhaps most importantly, salt marshes act as filters, buffering open waters and economically important fisheries from pollutants. At the same time, these marshes are one of the most threatened ecosystems in the United States. The results of Dr. Hughes' project are an important step towards predicting how further coastal development will change the way marshes work. In addition, the research will provide one of the largest, systematic datasets on bacterial distribution across geographic scales, providing a useful baseline for future sampling and experimental design in other ecosystem types. The research also includes the development of a new community based, problem-solving course entitled "Microbial Diversity and the Environment" at Brown University developed in tandem with a new environmental science course at a local high school, with joint field trips between the two groups. The courses will strengthen the connections between Brown students, the local community and Rhode Island agencies, as the students' projects will address environmental problems in Rhode Island in collaboration with agency scientists.