As Australia officially enters winter, UniSA ecologists are urging coastal communities to embrace all that the season brings, including the sometimes-unwelcome deposits of brown seaweed that can accumulate on the southern shores.
Scientists have discovered dramatic changes in the chemistry and composition of Sargassum, floating brown seaweed, transforming this vibrant living organism into a toxic “dead zone.” Results suggest that increased nitrogen availability from natural and anthropogenic sources, including sewage, is supporting blooms of Sargassum and turning a critical nursery habitat into harmful algal blooms with catastrophic impacts on coastal ecosystems, economies, and human health. Globally, harmful algal blooms are related to increased nutrient pollution.
Researchers at the University of New Hampshire find that environmental developments caused by climate change are contributing to the transformation of the seafloor to a lower, more patchy seascape dominated by shrub-like seaweed which could impact species habitats and the structure of the food web.
You’d think that losing 25 percent of your genes would be a big problem for survival. But not for red algae, including the seaweed used to wrap sushi. An ancestor of red algae lost about a quarter of its genes roughly one billion years ago, but the algae still became dominant in near-shore coastal areas around the world, according to Rutgers University–New Brunswick Professor Debashish Bhattacharya, who co-authored a study in the journal Nature Communications.