摘要
基于内蒙古中部农牧交错带乌兰察布市及周边20个气象站点1980-2017年的逐日气象资料,以相对湿润指数(M)作为干旱指标,采用反距离权重IDW插值法、距平及累计距平法、Mann-Kendall趋势检验法及偏相关分析分析了近38 a来作物生长季干旱空间分布特征、变化趋势及可能成因,并基于Hurst指数分析未来干湿变化趋势。结果表明:①乌兰察布市干湿状况为由北至南逐渐变湿,其中凉城、卓资、丰镇较湿润,四子王旗较干旱。近38 a来生长季M平均值为-0.575,为轻旱状态。②4-9月M呈先增后减,近38 a来该地区微弱变干,其中8月干旱化最显著(α=0.01)。③潜在蒸散量(ET0)与各气象要素的偏相关分析得出,风速对ET0的影响最大,其次是相对湿度、日照时数和平均温度。近38 a来干旱加重的主要原因是降水和相对湿度减小,其次是平均气温的上升,而风速、日照时数的下降有助于缓解干旱加重;Hurst指数表明该地区生长季将持续变干,其中8月为强持续显著变干。
In this paper, daily meteorological data from 1980 to 2017 of 20 meteorological stations in and around Ulanqab the typical region of the farming-pastoral ecotone in central Inner Mongolia are used to calculate the relative moisture index(M) to reveal the drought change trend. Based on the inverse distance weight interpolation method(IDW), anomaly and accumulated anomaly method, Mann-Kendall trend test method, partial correlation analysis method, the spatial distribution characteristics, the variation trend and the cause of drought in the crop growing season(April to September) of Ulanqab in the latest 38 years are analyzed, and Hurst index is used to analyze the trend of drought in the future. The results show that: ① The spatial distribution of drought in Ulanqab is getting drier gradually from the southern to the northern parts, among which Liangcheng, Zhuozi and Fengzhen are wetter, and Siziwang is getting drier. In the past 38 years, the average value of the M in the growing season is-0.575, indicating light drought. ② From April to September, the M increases first and then decreases. In the past 38 years, the region became slightly dry, especially in August, which showed the most significant drying trend(α=0.01). ③ Partial correlation analysis of potential evapotranspiration(ET0) and various meteorological elements showed that the wind speed impacted on ET0 significantly, followed by the relative humidity, sunshine duration and average temperature. The main factors that aggravate droughts are the decrease in precipitation and relative humidity,followed by the increase in average temperature,while the decrease in wind speed and sunshine hours can also alleviate the aggravation of droughts. Hurst index indicates that the growing season will continue to become dry in this region,and August will continue to become dry strongly.
作者
曹二佳
薛羽
李红瑛
巩杰
徐彩仙
Er jia;XUE Yu;LI Hong-ying;GONG Jie;XU Cai-xian(Key Laboratory of Western China's Environmental Systems with the Ministry of Education,College of Earth and Environmental Sciences Lanzhou University,Lanzhou 730000,China;Liangcheng County Meteorological Bureau,Liangcheng 013750,Inner Mongolia,China)
出处
《中国农村水利水电》
北大核心
2019年第11期165-171,共7页
China Rural Water and Hydropower
基金
国家自然科学基金重大项目(4179420015)
