Changes in Primary Production, Nutrient Fluxes, and Rates of Succession Following the Deployment of an Artificial Reef System in the Northeast Gulf of Mexic

The use of artificial reef systems has grown rapidly in the United States since the mid 1900s in both freshwater and marine habitats. However, whether these artificial systems accomplish their proposed goal to provide value to marine life and humans alike remains widely controversial. Few studies have examined the benefits of primary producers and the resulting changes in biogeochemistry that may influence the surrounding water column. Nutrients such as nitrogen and phosphorous in the water column and sediment serve as important fuel for primary producers which partially drive reef success. In this study, I examined the organisms and their rate of colonization on an artificial reef on the shallow Florida shelf in the Northeast Gulf of Mexico during its introductory year. I measured primary production, respiration, and nutrient fluxes of reef materials in a controlled laboratory setting, examining temporal as well as spatial trends and variability. I observed temporal differences in biomass and chlorophyll a production due to changes in in situ conditions. Benthic invertebrate biomass was greater than micro- or macroalgal biomass. I determined the reef was net heterotrophic with few differences between oxygen or nutrient fluxes in the light and dark. Exponential growth of benthic invertebrate community occurred during the first five months of this study and leveled off during the remaining 5 months. Microbial activity was significant, particularly nitrification during the second half of the study.