Landforms
Introduction Pages
An important kind of place Place is defined by physiographic processes--and on the platform we call these “landforms”, and name seven distinct types from mountains to sea, each shaped by distinct physical processes and with a particular ecological potential.
Headwaters - the steep foothill and mountain valleys, where precipitation falls as snow, and forestry is the primary land use. Landslides are a common disturbance.
Lowland Watersheds - Lowland watersheds contain the streams that drain the low foothills and the glacial plateau. These landform are shaped by glaciers and most precipitation falls as rain. Many lowland watersheds are urbanizing rapidly.
Floodplains - Floodplains form where the larger rivers and streams create and rework valley bottoms filled with their own alluvium. These are the best places for agriculture, the core of Chinook salmon habitat, and where flood risk is highest.
River Deltas - Deltas form where large river floodplains enter marine waters. Tidal flows create fluctuating water levels. Most of our deltas have been drained for agriculture, and lie below sea level protected by dikes.
Embayments - Embayments are those protected places along the shoreline where wind waves are muted by aspect or spits, and collect muddy sediments, sometimes forming salt marsh, often at the mouths of streams. Around 800 large embayments have been found on historic maps (Simenstad et al 2011).
Beaches - Beaches form where sediment from eroding shorelines are pushed alongshore by waves, creating bluffs, spits and lagoons. Beaches have been valued for residential property since time immemmorial, provide access to the wealth of the sea, but are vulnerable to storms.
Headlands - Rocky headlands emerge where bedrock is shallow along shoreines, along Juan de Fuca, San Juan Islands, and along the Seattle Fault. These dry stable shorelines contain pockets of beach. Our Bull Kelp forests are concentrated in these systems.