Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 2 of 2

Full-Text Articles in Life Sciences

An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly Jul 1987

An Annual Study Of Phytoplankton Composition And Associated Environmental Conditions Of Lake Trashmore, Virginia Beach, Virginia, Seba B. Sheavly

Biological Sciences Theses & Dissertations

A 12 month study of Lake Trashmore was conducted on phytoplankton composition, inorganic nutrients and their seasonal associations. The dominant phytoplankton groups observed were diatoms, chlorophyceans and cyanobacteria. Phytoplankton assemblage patterns were coupled with pH, temperature, dissolved oxygen, nitrites and silicates. Diatoms dominated during periods of high nutrient concentrations, cooler temperatures and an unstable water column. Cyanobacteria forms dominated during periods of warmer temperatures, higher pH and decreased nitrogen and dissolved oxygen concentrations. A seasonal community shift occurred from cyanobacterial dominance to chlorophycean dominance when pH levels decreased. The lake is eutrophic based on indices of chlorophyll a concentrations, transparency …


Is Growth Of Eelgrass Nitrogen Limited? A Numerical Simulation Of The Effects Of Light And Nitrogen On The Growth Dynamics Of Zostera Marina, Richard C. Zimmerman, Robert D. Smith, Randall S. Alberte Jan 1987

Is Growth Of Eelgrass Nitrogen Limited? A Numerical Simulation Of The Effects Of Light And Nitrogen On The Growth Dynamics Of Zostera Marina, Richard C. Zimmerman, Robert D. Smith, Randall S. Alberte

OES Faculty Publications

A numerical model of nitrogen uptake and growth was developed for the temperate seagrass Zostera marina L. Goals were to evaluate the relative effects of light and nitrogen availability on nitrogen uptake and partitioning between leaf and root tissue, and to estimate nitrogen concentrations in the sedment and water column required to saturate growth. Steady-state predictions are quite robust with respect to a range of parameter values justified by available data The calculations indicated that roots are probably more important in overall nitrogen acquisition in most light and nitrogen environments encountered in situ, but may contribute less than 50 …