My research integrates population, community, and ecosystem-level processes across multiple spatial scales to understand determinants of species and genetic diversity, and ecosystem properties in aquatic systems. Recently, the importance of space in mediating population connectivity and local species interactions has become increasingly recognized by ecologists and evolutionary biologists. This interest in spatial ecology has largely arisen from the urgent need to understand how fragmented landscapes alter dispersal and gene flow of threatened species, and how species invasions affect species richness and ecosystem functioning. Over the past decade, the metapopulation and metacommunity concepts have emerged as powerful frameworks in which to place population demography, community interactions, and ecosystem properties in a spatially explicit context. My research employs experimental and observational approaches to extend metapopulation and metacommunity theory to diverse freshwater species and landscapes