High CO2: Weeds take over kelp

on

Weedy plants will thrive and displace long-lived, ecologically valuable kelp forests under forecast ocean acidification, new research from the University of Adelaide shows. The researchers describe how kelp forests are displaced by weedy marine plants in high CO2 conditions, equivalent to those predicted for the turn of the century.

Carbon emissions will fuel the growth of small weedlike species, but not kelps – allowing weeds to take over large tracts of coastal habitats, the researchers say.

“Carbon emissions might boost plant life in the oceans, but not all plant life will benefit equally,” says project leader Professor Sean Connell, from the University of Adelaide’s Environment Institute. “Weedy species are quicker to capitalise on nutrients, such as carbon, and can grow faster than their natural predators can consume them.

“Unfortunately, the CO2 that humans are pumping into the atmosphere by burning fossil fuels gets absorbed by the ocean and favours weedy turfs, which replace kelp forests that support higher coastal productivity and biodiversity.”

Source: Weeds take over kelp in high CO2 oceans