关键词: 干旱区, 耕地后备资源, 荒漠化, 禁垦令

Abstract: In spite of large population and severe food security issues in China, arid northwest China can not be regarded as the main “farmland reserve base”. The reason is that arid northwest China faces the severe environmental problems including the reduction of alpine glaciers, shrinkage of rivers, dyingoff of desert vegetation, desertification, salinization, sandstorm, etc., and these problems result in the serious impact on ecological security and sustainable development of China. These problems can almost be found in Minqin County of Gansu Province, which can be called the “Minqin aporia”, characterized by the serious drawdown of groundwater level, everdeteriorating desertification, and even the appearance of ecological refugees. The socalled “farmland reserve resources” are actually the wellvegetated ecotones between oases and sandy deserts, which protect ecologically the oases against windblown sand disasters. Formed in a long history, they are very difficult or costly to restore once reclaimed. Viewing from national ecological security pattern, desertification prevention in arid northwest China is of countrywide significance. As a result, its ecological service function should be enhanced by developing areaspecific agriculture and watersaving irrigation based on scientific research and hightechnology. All of these can aim to make rational utilization of limited water resources in arid land. It is suggested that the central government issue the “Reclamation ban” to prevent farmland expansion and even to reduce farmland area in arid land. It could be responsible to increase and stabilize grain production of China in the main food production regions in east China.

Key words: arid land, farmland reserve resources, desertification, reclamation ban