Record Details
Bacteria-phosphate interactions in Upper Klamath Lake sediments
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Bacteria-phosphate interactions in Upper Klamath Lake sediments |
| Names |
Harrison, Michael John
(creator) Morita, Richard (advisor) |
| Date Issued | 1970-05-04 (iso8601) |
| Note | Graduation date:1970 |
| Abstract | Interactions between sediment bacteria and available phosphate necessary for algal production in a eutrophic lake were studied. Twenty percent of the organisms isolated solubilized phosphate forms such as CaHPO₄, Ca₃(PO₄)₂, FePO₄, Mg₃(PO₄)₂ and Al₂(PO₄)₂. Solubilization of phosphates occurred under conditions of aerobic growth. Upon quantitative analysis, some isolates were capable of solubilizing up to 87% of the inorganic phosphate. Solubilization was associated with carbohydrate metabolism and the production of organic acids, which function as chelating agents. Organic acids that solubilize phosphates include lactic, acetic, glycolic, pyruvic, citric, glyceric, glucuronic and gluconic acids. Carbohydrates added to sediment resulted in increased microbial activity and an increase in the level of soluble phosphate. Addition of precipitating ions (Ca⁺⁺ and Fe⁺⁺⁺) reduced the level of soluble phosphate in the sediment, but the soluble phosphate fraction could be increased by the stimulation of microbial activity. A. cyclic liberation of phosphate was associated with death during cryptic growth. Reversible liberation of phosphate was observed when facultative and aerobic organisms were shifted from aerobic to an anoxic environment. Phosphate solubilization, liberation of phosphate with cryptic growth, and the reversible uptake and liberation of phosphate by microorganisms, with changes in aeration, may be of significance in the exchange of phosphates between the water and the sediment in Upper Klamath Lake. |
| Genre | Thesis/Dissertation |
| Topic | Upper Klamath Lake (Or.) |
| Identifier | http://hdl.handle.net/1957/46227 |
