EFFECTS OF COLUMBIA RIVER DISCHARGE ON CHLOROPHYLL a AND LIGHT ATTENUATION IN THE SEA

摘要

The effects of Colunula RIVER discharge on chlorophyll A concentration and light attenuation In the sea off Oregon were examined In relation to effects of upwelllng, coastal runoff other than that from the Columbia ruler, and oceanic water.nChlorophyll a concentration and light attenuation within about ralles of the river mouth Is statistically different from that In other areas off Oregon In spring and summer, and possibly In winter though not enough data were available for analysis. Nutrient depiction with Increasing distance from the river mouth Is probably the major factor controlling chlorophyllnConcentration Although the Columbia Kovar plume extends southward offnOregon In summer, there are large Inshore-offshore chlorophyll and light extinction gradients at right angles to the plume axis. These gradients mask any possible differences created solely by water from the Columbia beyond 45 miles from the river mouth, Nutrlent-rlch water upwcltcd along the coast Is largely responsible for the Inshore-offshore gradtonts.