三江平原气象水文干旱演变特征

Evolution Characteristics of Meteorological and Hydrological Drought in Sanjiang Plain

利用三江平原6个气象站和4个水文站近50年的数据,采用标准化降水蒸散指数(SPEI)和径流干旱指数(SDI),探究了三江平原近50 a气象干旱和水文干旱时空演变特征,并对气象干旱与水文干旱进行了对比分析。结果表明:(1) 1970—1980年和2000—2010年气象干旱较为频发,从季节上看,三江平原大部分地区春季和冬季有变湿的趋势,而夏和秋两季有变干的趋势,但趋势均不显著。(2) 1960s末、1974—1981年和1999—2010年发生了持续时间长且强度大的水文干旱。挠力河流域菜咀子站水文干旱频发且严重,挠力河下游地区水文干旱程度强于上游地区。(3)水文干旱滞后于气象干旱1~7个月,且时间尺度越长,水文干旱滞后气象干旱的现象越明显。研究结果可以为三江平原地区干旱应对和水资源综合管理提供参考。

The standardized precipitation evapotranspiration index(SPEI)and runoff drought index(SDI)were used to examine spatial and temporal evolution characteristics of meteorological drought and hydrological drought in the Sanjiang Plain in the past 50 years.We collected data from 1961 to 2010 in 6 meteorological stations and 4 hydrological stations in the study area.The results showed that:(1)meteorological drought was frequent during the period 1970—1980 and period 2000—2010;the wet tendency in spring and winter occurred in most parts of Sanjiang Plain from a seasonal perspective;however,there was a non-significant dry tendency in summer and autumn in the study area;(2)in the late 1960 s,1974—1981 and 1999—2010,a longer and more intense hydrologic drought occurred;the hydrological drought intensity in the downstream was more serious than that in the upper stream;(3)hydrological drought had 1~7 months lag to meteorological drought;the time lag prolonged with the increase of the time scale.This study can provide the reference for drought management and integrated water resources management in Sanjiang Plain.