the columbia river is an ocean estuary.
the columbia river is an ocean estuary.
what type of estuary is the columbia river?
ocean
columbia river estuary









































the columbia river estuary is an estuary and a bay on the oregon–washington border and the pacific coast of the united states.









































if the columbia river estuary is defined by the region that experiences ocean tides, then the estuary extends up the columbia river to bonneville dam and up the willamette river to willamette falls (south of portland at oregon city, oregon). if the estuary is defined by the geographic land form or by the inland extent of salinity, then the estuary extends only as far as welch island.
columbia river estuary
nutrients dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the columbia river estuary and ocean. upstream in the headwaters, salmon runs are the main source of nutrients. dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton. the dams are also a barrier to salmon migration, and can increase the amount of methane locally produced. the columbia river estuary exports high rates of nutrients into the pacific ocean; with the exception of nitrogen, which is delivered into the estuary by ocean upwelling sources.
nutrient cycling in the columbia river basin