摘要
根据渭河上游渭源等11县(区)国家基本(一般)气象站1971年-2008年逐月气温、降水量、相对湿度、日照时数、风速等资料及渭河上游北道水文站1971年-2008年径流量资料,利用Penman-monteith(98版)公式计算了该区域的潜在蒸散量。建立了评价该地区干湿状况的干燥指数模型,对该区域气候、潜在蒸散量、干湿指数的变化特征及其干湿状况对地表水资源的影响进行了分析。结果表明,自1971年以来,渭河上游区域气温以0.3℃/10a的线性趋势上升;降水量呈较明显的周期变化;潜在蒸散以23mm/10a的线性趋势增加。干燥指数总体呈上升趋势,变化阶段性较强。1971年-1984年以0.826/10a的线性趋势降低,1984年-1997年以0.852/10a的线性趋势升高。渭河干流区域干燥指数较高,干燥指数较高的区域,正好与甘肃河东区域气候上的"干舌"相对应。1971年-2008年径流量以2567×104m3/10a的线性趋势减少。1984年-1997年径流量以9023×104m3/10a的线性趋势减少。干燥指数持续增大比较明显地影响了上游地表水资源,在一定程度上对下游水资源安全造成威胁。
Dry-wet status is one of important factors affecting surface water resources.To explore the variation relationship between the dry-wet status and surface water resources in the upper reaches of the Weihe River,data of temperature,precipitation,relative humidity,sunshine duration,and wind speed at 11 weather stations within the upper reaches of the Weihe River,and data of runoff at the Beidao hydrological station from 1971 to 2008 were used.Potential evapotranspiration was calculated using the FAO56 equation.A model of aridity index was built.Variations in potential evapotranspiration and aridity index,and the relationship between these factors and surface water resources were investigated.Results showed that the annual mean temperature increased by 0.3℃ per every ten years since 1971.The temperature increased with a generally linear trend in spring and winter.But in summer and autumn,the temperature increased insignificantly.The precipitation varied periodically.It is shown that the potential evapotranspiration increased by 23 mm per every ten years during the period 1971-2008.The potential evapotranspiration accounted for 43% of the annual value in summer,8% in winter,19% in autumn,and 30% in spring.The precipitation accounted for 52% of the annual value in summer,3% in winter,27% in autumn,and 20% in spring.The temporal distributions of evapotranspiration and precipitation did not seem to be correlated.It is indicated that the aridity index generally increased with the year.There was a variation in the dry-wet status.The aridity index decreased by 0.826 per every ten years from 1971 to 1984 and increased by 0.852 per every ten years from 1984 to 1997.The aridity index was generally higher in the main stream area.The relatively high aridity index corresponded to the climatic ＂dry tongue＂ area in the eastern Yellow River in Gansu.Runoff in the upper reaches of the Weihe River decreased by 25.67×106m3 per every ten years from 1971 to 2008,and reduced greatly in the 1980s and the 1990s.The runoff decreased b
出处
《资源科学》
CSSCI
CSCD
北大核心
2011年第7期1242-1248,共7页
Resources Science
基金
国家科技部公益行业专项(编号:GYHY200806021)
关键词
渭河上游
干湿状况
时空分布
地表水资源
关系
Upstream of Weihe river
Dry-wet status
Spatial and temporal distribution
Surface water resources
Relationship
