Vital coastal salt marshes could be submerged by 2100 SALT marshes which form a key natural defence against the impact of climate change will die out before the end of this century, Scottish scientists warned today. Researchers at the University of Edinburgh studying the coastal marshes predicted that although warmer temperatures will encourage plant growth over the coming decades a simultaneous rise in sea levels means the plants are likely to be submerged under water by the year 2100. The vegetation removes and locks away the same amount of carbon from greenhouse gases as about a third of the world's forests, so it's loss will leave significantly more carbon dioxide in the atmosphere, increasing global warming, experts said. Dr Simon Mudd of the university's School of GeoSciences said: "Salt marshes are extremely effective at removing carbon from our atmosphere, and it is worrying that they could all but disappear within the next century." The study, done in collaboration with scientists in the US, is based on computer models forecasting how salt marshes are likely to be affected by rising temperatures and sea levels. The results suggest that initially warmer temperatures will accelerate growth in the roots and leaves of the plants, helping to remove more carbon dioxide from the atmosphere for another 60 years. However at about this time, plants are predicted to start to decay faster than they are growing. From around the turn of the next century, rising sea levels are expected to "drown" many plants, killing them off so they can no longer store greenhouse gases. Previous research had suggested that sea levels would have an impact on salt marshes but the latest study, published in Nature, is the first to predict the combined effect of rising temperatures, CO2 and sea levels.