石羊河流域全新世不同时段降水量的估算

利用水热平衡模型,并结合实地考察和历史文献分析,恢复了石羊河流域全新世四个特征时期的降水量。结果表明:在6.5~5.8kaB.P、5.5~5.2kaB.P、3.6kaB.P、1.5kaB.P四个特征时期石羊河流域的降水量分别为167mm、157mm、152mm、147mm,分别比现在多30%、21%、15%和10%。降水量的这种变化趋势说明自全新世中期以来,石羊河流域的气候是趋于向干旱化的方向发展的。这一结论为研究本区土地退化、荒漠化等环境问题提供了自然背景。

Paleoclimatic Estimate During the Special Phases of Holocene in Shiyang River Drainage

Lake,as the container of surface water,is very sensitive to the water shortage and environment deterioration.Hydrological and energy balance model is a relative mature method of paleo-precipitaion resuming,and has been widely applied.By using the model and the field investation and results analysis,the precipitation during special phases in Shiyang River drainage was estimated.The results indicated that the precipitation in the drainage at 6.7～5.8ka B.P.,5.5～5.2ka B.P.,3.6ka B.P.,1.5ka B.P.,were 167mm,157mm,152mm,and 147mm respectively,which were more than that of present by 30%,21%,15%and 10% respectively.These results showed that the climate in Shiyang River drainage tended to be arid since the middle of Holocence.