The new risk to corals has been flagged by Professor Chan Lan Chun, who works at the Natural Resources Research Institute, University of Minnesota, Duluth, U.S. The concern is based on water samples taken from coastal inlets and oceanic outfall effluent water treatment plants, along Florida’s southeastern coast. These samples were compared with other sampled from water and coral tissues in reefs. The microbial content of the samples was analyzed using advanced molecular techniques (next generation DNA sequencing) that allow for accurate comparisons to be made.
The analysis indicates that certain bacterial species and fungal families are present both in the land-based sources and in water and tissues within the coral reefs. The associated requires the land-based organisms to have been spread across considerable distances, spanning anything from five to twenty-five miles. The evaluation was aided by using a special program called SourceTracker. The software allowed the research team to quantify the contributions from each of the land-based sources to the coral reef. The contributions were high and the researchers state this to be a confirmed “anthropogenic input.” In other words, clear signs of human impact on the environment. The Anthropocene is the proposed epoch dating from the commencement of significant human impact on the Earth’s geology and ecosystems.
The impact of the land-based microbes is probably significant. Corals are important animals, marine invertebrates that live in compact colonies and help to support a variety of marine life. The invasive microbes will change the community structure of the reef microbiome. This change is likely to affect the health of coral by impacting upon nutrient cycling and overall health; in turn this will impact upon the various animals and plants that live in the reef.
The research findings have been reported to the journal Applied and Environmental Microbiology. The research paper is titled “A Next-Generation Sequencing Approach to Characterize the Impacts of Land-based Sources of Pollution on the Microbiota of Southeast Florida Coral Reefs.”
