Aquatic landscapes: The importance of integrating waters

The landscapes of the Mid-Atlantic Region are dissected by networks of rivers, with their associated wetlands and riparian areas. These systems provide important ecosystem services, both ecological functions and societal values, such as floodwater storage, public water supplies, recreational greenbelts, and habitats for a diversity of flora and fauna. Ecologists and hydrologists have increasingly focused on integrating across the four dimensions of these ecosystems: longitudinal, lateral, hyporheic, and time. Here, we use a hydrogeomorphic classification system to describe wetland types, and present a conceptual model of how they connect to other waters through critical components such as hydrologic connectivity, energy flows and sources, and biological integrity. The connectivity of aquatic habitats is described and related in a watershed context. Concepts are supported by a technical review of pertinent literature. We emphasize the flow of water, nutrients, and organisms from headwaters downstream through an interconnected riverine ecosystem.