The characteristics and interactions of the riparian
stand, large woody debris (LWD), and channel morphology
were examined on five undisturbed, low gradient streams in
southeast Alaska. One first-, two second-, one third-,
and one fourth-order streams were studied. Stream
morphology variables were measured systematically at fixed
intervals of three to...
The characteristics and associated storage dynamics of approximately 2000 pieces of fine woody debris (FWD; 2.5 cm <diameter<10 cm and 0.3 m<length<10 m) was evaluated over a three-year period in two undisturbed
salmonid nursery streams in Southeast Alaska. To index a given reaches propensity to capture and store FWD over...
Hyporheic Exchange Flow (HEF) is driven by head gradients defined by the hydro-topography of the stream surface, which is controlled by the particular geomorphology of the stream. We quantified the impact of large wood, which typically exerts a strong control on stream morphology, on HEF in a second order, low...
The role of detritivores in the conversion of allochthonous
leaf material in two small streams in the Cascade Range of Oregon
was studied. Their importance in relation to other consumers was
estimated from emergence and benthic standing crop data.
Ingestion rates and efficiencies of utilization of bigleaf maple
(Acer macrophyllum)...
The ³²P material balance method for measuring periphyton production and grazing rates on periphyton in streams developed by Elwood and Nelson (1972) was evaluated by laboratory and field experiments. Three basic assumptions of the method were examined: 1) sloughing of periphyton from substrates is negligible, 2) sorption of ³²P onto...
The oxygen concentration in a stream is an important
parameter of water quality. Changes in oxygen concentrations
can affect various stream organisms including fish.
Foresters have become concerned with predicting the impacts
of forest activities on oxygen levels in streams. Slash,
which accumulates in streams as a result of harvesting...
The effects of sublethal concentrations of cyanide, pentachlorophenol and zinc individually and in combination on the growth and production of juvenile chinook salmon, Oncorhynchus tshawytscha (Walbaum), and aquatic invertebrates in model stream communities were studied in three experiments during 1971 and 1972 at the Oak Creek Fisheries Research Laboratory, Oregon...
Effects of current velocity, irradiance, and grazing on the
biomass, taxonomic structure, physiognomy, and chemical composition
of lotic algal assemblages were investigated. Four experiments,
lasting 32 to 75 days, were conducted in laboratory streams to
determine how these factors affect algal assemblages singly, and in
concert with each other.
Regardless...
Although there has been extensive research on the geomorphic and ecologic role of
large woody debris (LWD) in streams, the dynamics of LWD in streams are poorly
known due to various measurement difficulties during floods. In this thesis I present the
results of two flume experiments on the dynamics of...
