(full paper is archived in the Miller Library)
Title: Microbial activity in Monterey Bay beach sand in relation to the black sulfide layer
Student Author(s): Smith, Craig S.
Faculty Advisor(s): Phillips, John H.
Location: Final Papers Biology 175H
Date: June 1972
Keywords: sandy beaches
Abstract: An attempt was made to measure microbial activity in beach sand in relation to the black sulfide-containing layer. Three biogeochemical conversions were investigated. Changes in microbial activity as a function of sand depth were observed and found to be primarily correlated with differences in sand color. Conversion rates as determined in the laboratory were found not be good indices of in situ activity. However, since all results were comparative, they were able to give information about general activity distributions. Not only was anaerobic respiration involving sulfide production most pronounced in sands containing high amounts of sulfide, aerobic respiration was also greatest in this type of sand. On the other hand, the most rapid rates for autotrophic conversion of ammonia to nitrite were not associated with sulfide-rich sands.