50a来内蒙古荒漠草原气候干燥度的空间分布及其演变特征  

Spatial Distribution and Evolution of Climatic Aridity in Desert Steppe in Inner Mongolia in Recent 50 Years

作　　者：韩芳[1,2] 刘朋涛[2] 牛建明[1,3] 乌兰巴特尔 张庆[1] 张靖[1] 

机构地区：[1]内蒙古大学生命科学学院,内蒙古呼和浩特010021 [2]内蒙古生态与农业气象中心,内蒙古呼和浩特010051 [3]中美生态能源及可持续性科学研究中心,内蒙古呼和浩特010021

出　　处：《干旱区研究》2013年第3期449-456,共8页Arid Zone Research

基　　金：国家重点基础研究发展计划(973)项目(2012CB722201);国家科技支撑计划课题(2011BAC07B01);国家自然科学基金(31060320);内蒙古自然科学基金(2009ms0603);内蒙古气象局科技创新项目(nmqxkjcx200706);现代农业产业技术体系建设专项资金资助

摘　　要：根据内蒙古荒漠草原11个气象观测站1961—2010年的日平均气温、降水量资料,采用改进的谢氏干燥度计算公式,并利用ArcGIS软件分析内蒙古荒漠草原50 a来气候干燥度的时空变化规律。结果表明:①平均干燥度呈条带状自东南向西北逐渐递增,表明干燥程度由东南向西北逐渐加强;②除中部偏西(海流图地区)干燥度减少、气候趋于湿润化外,其他地区干燥度指数呈增加趋势,说明内蒙古荒漠草原地区气候干旱化趋势明显;③20世纪70年代属于相对湿润期,21世纪初干旱程度明显加大。其结果导致干旱区面积随年代增加,至21世纪初干旱区面积增加了近3倍,从另一个侧面说明研究区域气候干旱化趋势显著;④干燥度4.0等值线向东南方向移动,逐渐侵入典型草原。以20世纪60年代为基点,90年代前变幅相对较小,21世纪初的偏移范围最大。此外,该线在研究区域东部变化强烈,空间位移幅度大,西部相对变化较弱,空间位移相对较小。According to the average daily temperature and daily precipitation data from 11 meteorological stations in desert steppe in Inner Mongolia during the period of 1961--2010, the temporal and spatial variation of climatic aridity in the steppe in recent 50 years was analyzed using the improved formula of Selianinov AI and AreGIS soft- ware. The results are as follows： ① The average aridity and aridity degree increased gradually from the southeast to the northwest; ② Under the temperature increase and precipitation decrease in the steppe, the aridity index was in an increase trend in most regions except in the central-western region, that is the climatic drying trend in desert steppe in Inner Mongolia was significant; ③ According to the analyzed results of aridity, the 1970s was a relatively wet decade, and the aridity increased significantly in the early 21st century. The drought area was e year, it was enlarged for nearly three times up to the early 21st century, and the drought trend was nlarged year by significant ; ④ The 4.0-contour of aridity was gradually shifted towards the typical steppe southeastward. The 1960s was regarded as a starting decade, a relatively low variation occurred before the 1990s, but a significant variation occurred from the early 21st century. Moreover, the variation and the spatial shift amplitude were high in the east of the study are- a, and they were relatively low in the west.

关 键 词：荒漠草原 气候干燥度 时空格局 气候变化 干旱区面积 干旱化 内蒙古 

分 类 号：P468.0[天文地球—大气科学及气象学]