马莲河流域干燥度变化特征

Variation Characteristic of Aridity Index in Malian River Basin

[目的]研究马莲河流域干燥度变化特征。[方法]利用马莲河流域7个气象站1961—2015年地面观测资料,根据Holdridge生命地带模型对近55年来马莲河流域的干燥度变化特征进行了分析。[结果]近55年来马莲河流域内可能蒸散率(PER)以0.01~0.07/10 a的趋势上升,地区差异明显。马莲河流域PER 20世纪90年代出现了最大值,比20世纪60年代平均增大了0.36,为干旱最频繁发生时段。马莲河流域降水量呈减少趋势,减幅为1.3~13.9 mm/10 a,其中上中游降水量减少最为明显;年生物温度升高,增加趋势为0.13~0.29℃/10 a,下游地区年生物温度升高最为明显。[结论]马莲河流域出现了明显的暖干化趋势,对农业生产、经济社会发展的不利影响将更加显著。

[ Objective ] The research aimed to study the variation characteristic of aridity index in Malian River Basin. [ Method ] Using the surface meteorological observed data in seven climate stations in Malian River Basin during 1961 -2015 ,according to the Holdridge life zone model analyzed the variation characteristic of aridity index in Malian River Basin in recent 55 years. [ Result ] The possible evapetranspiration rate （PER） was increasing by the tendency of 0.01 to 0.07/10 a in the Malian River Basin in recent 55 years,and the regional differences were sig- nificant. The maximum value of PER in Malian River basin was in 1990s,the average increased by 0.36 than in 1960s,which was the most fre- quent occurrence of drought. The precipitation of Malian River Basin showed a decreasing trend,it was 13.3 to 13.9 mm/10 a,the precipitation reduction of the upper and middle reaches was the most obvious. Annual biological temperature was increased ,the increasing trend was O. 13 to 0. 29 ~C/10 a,the annum biological temperature increase was the most obvious in the downstream area. [ Conclusion] Malianhe River Basin has a significant warm -drying trend ,the adverse effects of agricultural production ,economic and social development will be more significant.