汾河灌区参考作物蒸散发量变化趋势及影响要素分析

Reference Evapotranspiration and the Factors Affecting It in Fenhe Irrigation District

气候变化直接影响着区域的水循环和水资源管理,而研究潜在蒸散发的变化趋势及其影响要素对于灌区的水资源管理具有重要的作用。选择汾河灌区,利用灌区内气象站的长系列数据,分析了灌区内参考作物蒸散发(ET0)的变化趋势及主要影响要素。结果表明,1951―2014年,灌区ET0没有明显的变化趋势,这主要是由于温度升高和相对湿度降低引起的ET0增加与风速下降和日照时间减少引起的ET0下降相当。温度、相对湿度和风速变化主要影响4―6月ET0,而日照时间则主要影响了5―9月的ET0。

Climate change has a great impact on hydrological cycle and water resource management in catchments.Under standing the change in reference evapotranspiration（ET0） in a catchment can improve its water resource management.In this paper,the change of ET0 in Fenhe Irrigation District and the factors affecting it were analyzed using long-term climatic data in this region.The results showed that the annual ET0 in Fenhe Irrigation District did not show a significant（P〉0.05） change from 1951 to 2014,because the positive effect of the increased temperature and decreased relative humidity on ET0 was compensated for by the negative effect due to the decreased wind speed and sunshine time.Changes in temperature,relative humidity and wind speed affected ET0 considerably from April to June,while sunshine hours impacted ET0 from May to September.Our results can help to efficiently allocate water resources in Fenhe Irrigation District as well asin the Fen River basin.