摘要：Global consumption of grains is projected to double by 2050 due to projected growth in population and per capita consumption of grains directly and also in livestock production as incomes rise. Global food security depends on expanding current farming activities in a sustainable way to meet this demand. Climate variability already has a significant influence on global grain production and further impacts on production are anticipated as the climate changes. Grain yields are likely to decline in tropical and subtropical regions, as well as in regions with ‘Mediterranean’ climates. They could potentially increase in more temperate regions. Adapting to climate change may be effective in lessening the negative impacts of small changes in climate. Studies of global food security indicate, however, that the world’s population will be exposed to a greater risk of hunger. In this paper we suggest that these studies may have significantly underestimated the risk to food security. Environmental limitations to grain production, increased variability in production and a range of policy constraints need to be addressed in a systematic and coherent way.
