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The Role Of Iron Nutrition In Regulating Patterns Of Photosynthesis And Nitrogen Metabolism In The Green Alga Scenedesmus Quadricauda, Dennis Raymond Ades
The Role Of Iron Nutrition In Regulating Patterns Of Photosynthesis And Nitrogen Metabolism In The Green Alga Scenedesmus Quadricauda, Dennis Raymond Ades
Dissertations and Theses
The influence of iron nutrition on patterns of photosynthetic behavior, nitrogen metabolism, and fixed-carbon allocation is reported for a common freshwater green alga. Cultures of Scenedesmus quadricauda were grown in Fraquil medium in which iron concentrations ranged from 1.0 μM to 0.01 μM (log 10-6 to 10-8 M, respectively). Carbon 14 and nitrogen uptake experiments were conducted at photosynthetically saturating and subsaturating photon flux densities.
The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly
The Role Of Copper In The Apparent Aluminum Toxicity Of Aquatic Systems, Kirk Thomas O'Reilly
Dissertations and Theses
The effect of variations in aluminum and copper concentrations on the growth rate and enzyme activity of the green alga Scenedesmus quadricauda was investigated. The goal was to determine which chemical species control the biological parameters. The computer program MINEQL (Westal et al 1976) was used to estimate chemical speciation. In the prevalence of both metals, algal growth rate and alkaline phosphatase activity could be correlated to cupric ion activity. The activity of isolated bacterial alkaline phosphatase was found to be a function of both total copper concentration and cupric ion activity. A model was developed to predicted the effects …
Influence Of Light On Algal Growth In The Lower Willamette River, Stephen Arthur Wille
Influence Of Light On Algal Growth In The Lower Willamette River, Stephen Arthur Wille
Dissertations and Theses
During the summer of 1974 chemical conditions in the lower reaches of the Willamette River, Oregon were similar to those in other rivers currently experiencing nuisance algal growth problems. Temperature and chemical nutrients are not limiting. Relatively high populations of phytoplankton and productivity values for upstream periphyton beds and surface waters suggest moderately eutrophic conditions. However, with increased depth in the lower river, and a constant euphotic zone, the amount of photosynthetically available light is reduced. With sufficient depth and complete mixing the critical depth is exceeded. Primary productivity rates are subsequently limited by low light availability in the lower …