This study was made to estimate seasonal abundance, growth, mortality and biomass of planktivore fish by species and age groups
on Lake Washington, Lake Sammamish, and Chester Morse Lake, and to incorporate this information with other studies to test trophic dynamics models. Work in the initial year was directed toward...
Lakes Findley, Chester Morse and Sammamish, Washington, are characterized
by one major outburst of phytoplankton productivity and biomass (mainly
diatoms) with usually no or low fall activity. Vernal outbursts were
often delayed in the monomictic lakes by inadequate light because of
unfavorable climate and/or a lack of thermal stratification. Strong...
Sample collection to define the phytoplankton biomass and productivity in Lakes Findley, Chester Morse, and Sammamish was conducted according to the schedule In Figure 1. Methods and procedures are the same as those
used in 1972 (Welch et al. 1972). The purpose of such sampling is to provide validation data...
Nitrogen fixation rates were determined periodically by the acetylene
reduction technique at three depths in each of the lakes. Fixation began
in June in Lakes Washington and Sammamish and peaked during July and
August. Chester Morse and Findley Lakes did not exhibit acetylene
reduction activity until August and the rates...
The physical framework or matrix in which the biological processes of aquatic ecosystems occur is currently under investigation at the Castle Lake Research Station. Special attention has been given these physical parameters in view of their close interrelationship with important biological properties within the lake (as exemplified by the rate...
The feasibility and enumeration studies have led to the following conclusions: The nitrogen fixation studies should be done in 1973, using acetylene reduction technique with some verification by N15. The denitrification studies should be done with N15 technique. The decision to continue more enumeration sampling of nitrogen transforming bacteria should...