Education and training Student projects and theses Graduation thesis

Graduation thesis Ecotoxicological assessment of methods for the management of eutrophication-associated features

Supervisor Supervisor:

Student Student: Daniel Jančula

Status Status: finished

Year Year: 2006

Nuisance of algal blooms is one of the results of eutrophisation. This work compares three types of algicides to control algal blooms and methods, how to test algicides efficiency to inhibit natural filamentous algae. Thesis also solve a problem of algal blooms development in cooling towers in nuclear power station in Dukovany as a model of locality, where it is necessary to eliminate growth of algae with methods minimalizing an negaive impact on environment. Three types of algicides were tested on selected test battery of organisms depending on potential usage of these compounds. Twentyseven phthalocyanines were tested on green algae Pseudokirchneriella subcapitata, cyanobacterium Synechococcus leopoliensis and crustacean Daphnia magna. Twelve algicides were tested on two algal cultures Pseudokirchneriella subcapitata, Scenedesmus quadricauda, two cyanobacterial cultures Synechococcus leopoliensis, Microcystis aeruginosa and on natural filamentous algae Cladophora glomerata. Antifouling compounds were tested directly in cooling towers of nuclear power station Dukovany. Toxicity testing on natural algal blooms was performed by four methods chlorophyll a assessment, fluorescent SCA method, difference in pH and oxygen levels. In terms of these experiments, one method was selected and used to create standard operating procedure (SOP) for testing of algicides on natural filamentous alga. The main criteria were relevancy, time, and cost efficiency. Tested phthalocyanines showed potential usage in water management including a reduction of algal blooms. The most effective algicide in tests with laboratory algal cultures and natural filamentous alga was Algiflash. The best results as antifouling paint showed Sigma Plane HA Antifouling coating. After evaluation of all important criteria, the chlorophyll a assessment was chosen as a method to determine toxicity of algicide compounds and standard operation procedure (SOP) Determination of algicidal effect on filamentous alga Cladophora glomerata acute toxicity test was prepared.