The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community
Issue link: http://sea-technology.epubxp.com/i/571837
62 st / September 2015 www.sea-technology.com Carbon Dioxide Shifts Reefs to Algae Carpets Scientists from NOAA and the Co- operative Institute for Marine and At- mospheric Studies at the University of Miami Rosenstiel School of Marine and Atmospheric Science have documented a dramatic shift from vibrant coral com- munities to carpets of algae in remote Pacifc Ocean waters where an under- water volcano spews carbon dioxide. The research, published in Nature Climate Change, provides a stark look into the future of ocean acidifcation. Healthy coral reefs provide food and shelter for abundant fsheries, support tourism and protect shore- lines from storms. A shift from coral to algae-covered rocks is typically accompanied by a loss of species di- versity and the benefts that reefs pro- vide. The research was conducted on Maug, an uninhabited volcanic island in the Northern Mariana Islands about 450 mi. from Guam. This location al- lowed scientists to single out a small geographic area that experiences car- bon dioxide levels that vary from pres- ent day to those predicted for a hundred years in the future. Underwater instruments measuring the effects of carbon dioxide showed that coral cover decreased under higher levels of carbon dioxide, giving way to less desirable algae-covered rocks near the volcano's vents. Latest Analysis of St. Johns River Basin The latest report on the lower St. Johns River Basin shows positive signs of the waterway's health improving, but reveals concerns of deterioration. Some positive trends include: lower nitrogen levels; a decline in fecal co- liform; improvement in turbidity—a key test of water quality; and a drop in phosphorus levels. There are also some positive trends that haven't changed much over the years, including generally healthy and stable fsheries, as well as stable threat- ened/endangered species. There are some factors indicating declining river health, including an increase in overall surface water dis- charges of toxic chemicals; contami- nated sediments; high levels of phyto- plankton, including algal blooms with potentially harmful levels of cyanobac- teria toxins; and fsh consumption advi- sories due to mercury. Eavesdropping to Assess Reef Health Scientists have tested a surprisingly cheap and effective way to assess the health of vulnerable coral reefs and to monitor threats on remote atolls: eaves- dropping. In a study published in Marine Ecology Progress Series, scientists at Woods Hole Oceanographic Institution (WHOI) used low-cost autonomous un- derwater recorders over four months to collect soundscapes of reefs in the U.S. Virgin Islands. They showed how the collective sound recordings of reef in- habitants painted vivid pictures of the reefs' abundance and diversity. In a second study, the researchers recorded boat noise—showing how it could mask vital sounds that organ- isms make to reproduce, feed and fnd environmental monitoring Sea Technology Buyers Guide/Directory Published since 1969, this comprehensive tool, including contact details, assists in the location of products and services of companies that have the answers. Available in both print and digital formats. INDUSTRIAL FIRMS, PRODUCTS BUYERS GUIDE, SERVICES BUYERS GUIDE, EDUCATIONAL INSTITUTIONS, FEDERAL GOVERNMENT, GEOPHYSICAL SURVEY VESSELS, OCEANOGRAPHIC RESEARCH VESSELS For ordering information, please contact: Compass Publications, Inc. • 1600 Wilson Blvd., Suite 1010,