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Effects of Hydrazine and Other Toxicants on Early Life Stages of California Brown Algae


James, David Earl (1989) Effects of Hydrazine and Other Toxicants on Early Life Stages of California Brown Algae. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/WRCJ-G589.


Toxicity of hydrazine to early life stages of several species of California brown algae was demonstrated to occur at environmentally relevant concentrations. Effects of hydrazine on benthic organisms had not been previously studied.

Preliminary studies evaluated toxicity of boric acid, chlorine (as hypochlorite), lithium ion, tributyltin chloride and Zn(II).

A reliable bioassay technique was developed using digital image analysis to measure vegetative growth inhibition of brown algal gametophytes. Hydrazine toxicity threshold of Macrocystis pyrifera gametophytes was almost constant in 10 96-hour experiments, ranging from 3 - 5 ppb (96-160 nM).

Differences in resistance to short-term hydrazine exposures were observed among three algal families of the order Laminariales. Two of three tested members of the family Alariaceae, Pterygophora californica and Eisenia arborea were among the most resistant species tested. The three tested species in the family Lessoniaceae, Macrocystis pyrifera, Nereocystis luetkeana and Pelagophycus porra, all fast-growing canopy-formers, were among the most sensitive tested species. Tested representatives of the family Laminariaceae varied in resistance. Laminaria farlowii was resistant. Laminaria dentigera and Laminaria ephemera were fairly sensitive.

Hydrazine autoxidation rates varied by an order of magnitude in seawater sampled from different locations. Rates showed strong temperature dependence. Autoxidation at 10°C and below was much slower and indicated a higher activation energy than autoxidation at 20°C and above.

Undiluted trace hydrazine powerplant emissions from a time period when algal community composition changed in the vicinity of an outfall were compared to growth inhibition results from multivariate hydrazine toxicity experiments on Macrocystis gametophytes. Results indicated that several trace hydrazine discharges were of sufficient duration and concentration to have inhibited algal microscopic stages.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Brown algae, hydrazine, bioassay, gametophytes, image analysis, seawater, autoxidation, powerplant, environmental engineering science, oceanography
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Environmental Science and Engineering
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • North, Wheeler J.
Thesis Committee:
  • North, Wheeler J. (chair)
  • Brooks, Norman H.
  • Brokaw, Charles J.
  • Morgan, James J.
  • Jackson, George
  • Hoffmann, Michael R.
Defense Date:2 December 1988
Funding AgencyGrant Number
Earle C. Anthony FellowshipUNSPECIFIED
Gas Research InstituteUNSPECIFIED
William and Flora Hewlett FoundationUNSPECIFIED
Virginia Steele Scott FellowshipUNSPECIFIED
Josephine de Karman Fellowship TrustUNSPECIFIED
Pacific Gas and Electric CompanyUNSPECIFIED
Record Number:CaltechETD:etd-02062007-131016
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:522
Deposited By: Imported from ETD-db
Deposited On:28 Feb 2007
Last Modified:12 Aug 2021 23:50

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