URBANIZATION, FLOOD FREQUENCY, AND SALMON ABUNDANCE IN PUGET LOWLAND STREAMS

摘要: : Urbanization history and flood frequencies were determined in six low-order streams the Puget Lowlands, Washington, for period between 1940150s 1980190s. Using discharge records from USGS gauging stations, each basin was separated into periods prior to after urban expansion. Four of study basins exhibited significant changes urbanized area, whereas two only limited change area effectively serve as control basins. Each that experienced a increase increased frequency; pre-urbanization 10-year recurrence interval discharges correspond 1 4-year events post-urbanization records. In contrast, no discernible shift frequency observed either Spawner survey data available three reveal systematic declines salmon abundance urbanizing evidence decreases basin. These imply link ongoing population or associated habitat structure.