Session Description: Human impacts are pervasive across the modern landscape. Land use, resource extraction, and other human activities alter vegetation cover and species distributions; alter surface topography and disrupt soil layers; move large quantities of rock, soil and other materials; re-route surface and subsurface water flows; and directly or indirectly introduce large quantities of chemicals across the landscape, among other impacts. These many impacts affect key watershed processes even in relatively remote areas, altering the routing and delivery of water, sediment, organic matter, and dissolved chemicals to rivers and streams and in turn altering channel and floodplain morphology, aquatic habitat quality, and riparian ecosystem structure and function. Because humans depend upon watersheds for water supply, recreation, and many ecosystem services, understanding and management of human impacts on watershed processes is profoundly important to human societies. This series of sessions explores human impacts to hydrogeomorphic, biogeochemical, and ecological systems and processes in watersheds in a range of environments. Primary focus areas include (1) geochemistry, water quality, and ecological processes; (2) watershed restoration and management, and (3) Impacts of land use change on hydrological and geomorphic processes.
