关键词: 中国干旱区, 全球变化, 响应

Abstract:

With the global warming, the air temperature in the arid regions in China rose over the past 50 years. A special evidence was that the speed of air temperature rising became much higher since the medium and late term through 1980 to 1990 Meanwhile, precipitation increased substantially, and wind power and the days of gale decreased continually, and evaporation capacity decreased successively. Increase of precipitation and reduction of wind power counteracted the calefactive effect, and resulted in improvement of humid conditions, and increase in river discharge and water level in the arid regions. Area of oases had not decreased, although types, structures and functions of those oases had a continual chang over the past 50 years. Threat against oases was not due to climate change, but to human activities. Under the conditions of precipitation increase as well as artificial protection and control, vegetation condition was improved and expansion trend of desertification was initially contained in the arid regions. Although there were some instances that disaccorded to general trends in some local areas or in some years in the whole arid regions, in the view of general trends, basic conditions in the arid regions were described as above in the context of global change. Despite the substantial increase in precipitation, the base of original precipitation was so small that increased precipitation was still low. As a result, neither the fundamental status as scarcity of water resource and precipitation nor the landscape of droughtdesert in the arid regions will change, and vulnerability of ecoenvironment system will have no fundamental transform in the arid regions.

Key words: the arid regions in China, global change, response