摘要
基于1969—2016年渭北黄土台塬区10个气象站实测资料,计算不同时间尺度标准化降水蒸散指标(SPEI),采用Mann-Kendall检验、Morlet小波分析、R/S分析等方法,研究了区域干旱时空演变特征。结果表明:(1)48 a来渭北黄土台塬区年及四季干旱均呈增强趋势,未来有很大可能继续向干旱化发展;(2)年干旱在1991年发生显著突变,春、夏、秋、冬季干旱分别在1996年、2010年、2002年、1978年发生显著突变;(3)年及春、夏、秋季均明显存在着4~18 a的短周期和20 a以上的长周期,冬季明显存在3~11 a的短周期和12~30 a的长周期;(4)轻旱、中旱、重旱、极旱发生频率自西向东分别呈“高—低—高—低”、“逐渐增高”、“逐渐降低”和“中间高两边低”的分布规律,且干旱发生频率整体上符合轻旱>中旱>重旱>极旱的规律;(5)春季干旱演变对年干旱演变的贡献率最大。研究结果有助于了解区域干旱演变特征,为水文生态建设及社会经济可持续发展提供科学支撑。
Based on the measured data of 10 meteorological stations in the Weibei loess tableland area from 1969 to 2016,the standardized precipitation evapotranspiration indices(SPEI)at different time scales were calculated,and the spatial and temporal evolution characteristics of regional drought were studied by Mann-Kendall test,Morlet wavelet analysis,R/S analysis and other methods.The results show that:(1)the annual and seasonal drought in the Weibei loess tableland area had been increasing in the past 48 years,and it is likely to continue to develop toward aridity in the future;(2)the annual drought had a significant mutation in 1991,while the drought in spring,summer,autumn and winter had a significant mutation in 1996,2010,2002 and 1978,respectively;(3)there were obvious short cycles of 4~18 years and long cycles of more than 20 years in spring,summer and autumn,and there were obvious short cycles of 3~11 years and 12~30 years in winter;(4)from west to east,the occurrence frequencies of light drought,medium drought,severe drought and extreme drought showed the distribution patterns of‘high-low-high-low’,‘gradually increasing’,‘gradually decreasing’and‘low on both sides of the middle high’,respectively;moreover,the frequency of drought from big level to small level was moderate drought,mild drought,extreme drought and heavy drought;(5)the contribution rate of spring drought evolution to annual drought evolution was the largest.These results are helpful to understand the characteristics of regional drought evolution and provide scientific support for hydrologic ecological construction and sustainable development of social economy.
作者
刘宇
李雯晴
刘招
余玉聪
尤烽骅
杨舟
LIU Yu;Li Wen Qing;Liu Zhao;Yu Yucong;You Fenghua;Yang Zhou(School of Water and Environment,Chang′an University,Xi′an 710054,China;Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of Ministry of Education,Chang′an University,Xi′an 710054,China;Institute of Water and Development,Chang′an University,Xi′an 710054,China)
出处
《水土保持研究》
CSCD
北大核心
2021年第1期109-117,共9页
Research of Soil and Water Conservation
基金
高等学校学科创新引智计划(“111”计划)项目(B08039)
陕西省重点研发计划项目(2019SF-237)
中央高校基本科研业务费资助项目(300102299206
300102269201)
西安市建设科技计划项目(SJW2017-11)。
