Grass land responses to Co_2

摘要

Elevated CO_2 and elevated temperature, the cause and consequence of climate change, are predicted to have opposing effects on plant productivity: temperature increases desiccation but CO_2 improves water use efficiency. The relative strengths of the two effects are, however, hard to predict. An experimental warming and elevated CO_2 study shows that in semi-arid grassland, the CO_2 effect can completely counter the warming effect. This finding is particularly relevant to semi-arid and seasonally dry regions, which are likely to become even drier under climate change, as it suggests that it is precisely here that high CO_2 will do most to ameliorate the desiccating effects of climate change.