Ocean Visibility and Optics Lab

Project Managers

Fraser Dalgleish (Engineering), Brian Lapointe (Science)

Project Description

Background

Blooms of toxic algae are ever increasing in frequency and magnitude all around the earth. In southeast Florida, coral reefs are experiencing unprecedented macroalgal blooms and invasion (Lapointe et al., 2005). Anthropogenic causes of this “new” growth, in SE Florida, can be linked to improper waste management caused by both deep well injection and indirect leaching of nutrient-rich waste-water into aquifers which eventually transport the nutrients into the ocean. The effects of the resulting macroalgal overgrowths are most damaging to fragile coral reef environments.

Technology

The objectives of this research are to expand the spatial and temporal boundaries for specific macroalgal bloom detection and tracking by acquisition of key environmental parameters as well as high resolution color images, in order to gain more understanding of the underlying mechanisms leading to these macroalgal blooms. The project involved the integration and testing of a sensor-pack (CTD, chl-a fluorometer and transmissometer) onto the Ocean Explorer (OEX) autonomous underwater vehicle (AUV), together with a PAR (Photosynthetically Active Radiation) sensor and a low noise, high definition camera system for algae species identification.

The OE-X AUV is operated by our colleagues at FAU Sea Tech, Professor Edgar An, and Rob Coulson (Engineer).

Previous efforts involved the use of the HBOI Bobcat ROV system (Dalgleish et al., 2005).

Broader Impacts

Project efforts will also be directed towards refining our ability to qualitatively/quantitatively identify HAB species in field populations, and to correlate rapid macroalgal growth and harmful blooms as consequential events of aquifer eutrophication caused by improper waste management (waste-water leaching).

References

Lapointe B, Barile P, Littler M, Littler D, Bedford B, Gasque C. 2005. Macroalgal blooms on southeast Florida coral reefs I. Nutrient stoichiometery of the invasive green alga Codium isthmocladum in the water Caribbean indicates nutrient enrichment. Harm. Algae 4 1192-1105

Lapointe B, Barile P, Littler M, Littler D. 2005. Macroalgal blooms on southeast Florida coral reefs II. Cross-shelf discrimination of nitrogen sources indicates widespread assimilation of sewage nitrogen. Harm. Algae 4 1106-22

Dalgleish, F.R., Fuchs, E and Lapointe, B.E. 2005. Remote Imaging System for Monitoring Macroalgal HABs in Deep Reef Communities off Southeast Florida. Presented at 3rd Symposium on Harmful Algae in the U.S., Oct 3-7, Monterey, CA.