【摘要】 根据河西走廊荒漠-绿洲交错区敦煌、金塔及民勤3站1960-2007年气温、降水、蒸发量等观测资料,利用距平时间序列和多阶自回归序列分析方法,探讨荒漠-绿洲交错区的年际气候演变特征。结果表明:在1960-2007年荒漠-绿洲交错区年均气温分为两个主时段,即1967-1986年为一低温时段,1987年开始转为一个相对较长的偏暖时段。目前,年均气温正处在历史的波峰状态,年均蒸发量显著增加。利用荒漠-绿洲交错区1980-2007年灌溉面积、地下水开采状况等资料,分析其历史演变特征,说明了在气候变暖的背景下,人类活动与环境的不相适应,大量扩耕、超采地下水是导致荒漠-绿洲交错区气候环境退化的主要原因之一。更多还原

【Abstract】 Based on the air temperature,precipitation and evaporation data observed by the Dunhuang,Jinta and Minqin meteorological stations in the Hexi Corridor,Gansu Province during the period from 1960 to 2007,in this paper the climate change characteristics in desert-oasis ecotones in the Hexi Corridor are researched using the anomaly time series and the multi-order autoregression series analysis.The results show that there were two stages of annual temperature change in desert-oasis ecotones in the Hexi Corridor in recent 48 years from 1960 to 2007,that is,the temperature was low during the period from 1967 to 1986,but it began to increase from 1987,in which the temperature increase rates in Minqin,Jinta and Dunhuang were 0.051℃/a,0.060 6℃/a and 0.063 8℃/a respectively, and the annual temperature is currently at its historical peak stage.The annual evaporation is significantly increased,thus the topsoil moisture content is decreased by 3.546%/10 a.Moreover,the change of groundwater level in desert-oasis ecotones in the Hexi Corridor is also analyzed based on the data of irrigation areas and pumped groundwater volumes in the corridor during the period of 1980-2007.The results reveal that human activities, such as the enlargement of the areas under cultivation and over-pumped groundwater,is one of the main causes resulting in environmental degeneration in the corridor under the background of climatic warming.更多还原