Influence of Saharan Dust Deposition on the Growth of Harmful Marine Bacteria and Algae in Texas Coastal Waters

Principal Investigator

Massive plumes of Saharan dust travel in the atmosphere across the Atlantic Ocean and are
deposited in surface waters of the Gulf of Mexico during summer, delivering essential nutrients
that facilitate rapid growth of microbes. Previous studies in the Florida Keys showed that the abundance of Vibrio bacteria (including several human pathogens) increased by orders of magnitude after dust deposition. Other studies have also demonstrated a link between dust and the growth of the “red tide” dinoflagellate, Karenia brevis, in the eastern Gulf of Mexico.

The primary research goal of this study is to understand how Saharan dust affects the growth of
marine microbes in Texas coastal waters, specifically emphasizing Vibrio and secondarily
harmful algal bloom (HAB)-forming phytoplankton taxa, which are important to public health.
To accomplish this, high-frequency field sampling and experiments will be conducted during
summer (when dust deposition occurs) at sites spanning a range of nutrient conditions, all of
which are popular for waterborne activities.

Specific objectives are to:

  1. Quantify the effects of Saharan dust on harmful coastal marine microbe populations, and
    on the broader microbial community abundances and composition.
  2. Quantify the relative importance of dust deposition and other environmental drivers on
    the spatial-temporal distribution of marine microbial populations and community