【摘要】 了解西辽河流域气候干湿指数变化规律与特征对区域水资源利用具有参考意义。利用西辽河流域30个气象台站1961—2018年逐日气温和降水量资料,采用Thornthwaite干湿指数、Mann-Kendal非参数检验、小波分析、气候干湿划分指标等方法,分析了干湿指数时空变化趋势。结果表明,（1）近58年来,年平均干湿指数与年平均气温、年潜在蒸散量、年降水量分别呈极显著性负、负、正相关,在年平均气温显著升高、年潜在蒸散量显著增加、年降水量略呈减少趋势的协同作用下,干湿指数略呈降低趋势,干湿指数变率为-0.050 a^-1。年平均气温、年潜在蒸散量突变点分别在1991年和1995年,而年平均降水量和年干湿指数两者没有表现出突变情况。在降水量和潜在蒸散量多时间尺度周期叠加作用下,形成干湿指数25—35、10—15 a的年代际尺度主周期和次周期背景下,5—10 a年际尺度准周期显著,58 a出现10次,体现了西辽河流域干湿指数与相关气候因素在多时间尺度周期上的一致性。（2）干湿指数变率空间变化总体上由西南向东北呈降低趋势,其变率范围为-0.290—0.130 a^-1。其中,西南部区域（除喀喇沁旗、八里罕、翁牛特旗外）和东部双辽市的干湿指数呈增加趋势,其他区域干湿指数呈降低趋势,且北部区域降幅相对较大,其空间变化是降水量、潜在蒸散量变化协同作用所致。西辽河流域干湿指数在时间变化上略呈降低趋势,变率为-0.050 a^-1,5—10 a年际尺度准周期显著;其空间变化总体上由西南向东北呈降低趋势,变率范围为-0.290—0.130 a^-1;西辽河流域干湿指数与相关气候因素的时空变化具有一致性和协同性。更多还原

【Abstract】 Understanding the change law and characteristics of climate dry-wet index in Xiliao River Basin can provide reference for regional water resources utilization.Based on the daily air temperature and precipitation data from 30 meteorological stations in Xiliao River Basin from 1961 to 2018,the spatio-temporal variation trends of the dry-wet index were analyzed by using the Thornthwaite dry-wet index,Mann-Kendal non-parameter test,wavelet analysis,dry-wet climate indicators and other methods.The results showed that:（1） In the past 58 years,the yearly average dry-wet index had extremely significant negative correlation with the yearly average air temperature,yearly potential evaporation,and had extremely significant positive correlation with the yearly precipitation,the dry-wet index were decreased slightly with the significant increase of yearly average air temperature,yearly potential evaporation,and the slight decrease of yearly precipitation,change rate of dry-wet index was-0.050 a^-1.The abrupt change points of yearly average air temperature and yearly potential evaporation were respectively in 1991 and 1995,but there were no abrupt changes for yearly average precipitation and yearly dry-wet index.Under the superimposition of multiple time-scale periods of precipitation and potential evaporation,the dry-wet index had the major and minor interdecadal period background of 25–35 years,10–15 years,and had the significant interannual quasi-period of 5–10 years,the interannual period had 10 times in 58 years.The consistency of multi-time scales was showed between dry-wet index and related climatic factors in Xiliao River Basin.（2） Overall,the spatial variation of dry-wet index was decreased trend from southwest to northeast,its variation range was-0.290–0.130 a^-1.Among which,the dry-wet index in southwest region （except Kalaqin Banner,Balihan and Wengniut Banner） and east Shuangliao were increased trend,the dry-wet index in other regions were decreased trend,and the north region were relatively large decrease.The spatial variation of dry-wet index was caused by the variable cooperation of precipitation and potential evaporation.The following conclusions can be drawn:The temporal variation of dry-wet index were decreased slightly in Xiliao River Basin,its change rate was-0.050 a^-1,its interannual quasi-period of 5–10 years was significant.Overall,the spatial variation of dry-wet index was decreased trend from southwest to northeast,its variation range was-0.290–0.130 a^-1.The spatio-temporal variation had consistency and cooperation between dry-wet index and related climatic factors in Xiliao River Basin.更多还原