Press Trust of India: Global warming could trigger a dramatic decline in diversity of plant species on the rangelands in the Qinghai-Tibet plateau in southwest China, American and Chinese scientists warned, as research showed a 26 to 36 per cent drop in plant species from 1998 to 2001. Experts said global warming specifically caused loss of 21 per cent of medicinal plants and 25 per cent of pasture plants. Research into climate change and grazing in northeastern Qinghai-Tibet plateau had shown the …