Wetlands are an important ecosystem that are permanently or seasonally dominated by water. The primary factor that distinguishes wetlands from other bodies of water is the characteristic presence of aquatic plants adapted to the unique environment. Wetlands play an important role in the environment, including water purification, water storage, processing of carbon and other nutrients and stabilization of shorelines. Wetlands are also home to a wide variety of plant and animal life. The historic twin barns reflected in a wetland was photographed at the Nisqually National Wildlife Refuge near Olympia, Washington State, USA.