Human threat to grassland ecosystems

A manmade pollutant is having a significant impact on our global environment according to a new study published in 'Ecology' this month (June 2015). Human activity, such as burning forests and fossil fuels, increasing dependence on farm fertilizers and more livestock waste, has led to high levels of atmospheric nitrogen. An international investigation, led by Dr Carly Stevens, found that grasslands - including prairies, alpine meadows and savannahs - grew more abundantly as atmospheric nitrogen increased. Surprisingly, they also found atmospheric nitrogen had a bigger effect on grasslands growth than any other factor - including local climate and rainfall. This increase in grassland growth has previously been linked with reduced species richness, which poses a threat to biodiversity. Grasslands cover 40 percent of the earth's surface storing 34 per cent of terrestrial carbon. Therefore any change to grassland growth patterns could have a significant impact on earth system processes.