Author(s): ZHAO Lu, LIANG Chuan, School of Water Resources and Hydropower, Sichuan University, Department of Civil Engineering, Sichuan College of Architectural Technoledge
Pages: 26-30
Year: 2014 Issue:  4
Journal: Research of Soil and Water Conservation
Keyword:  FAO-56Penman-Monteith; Sichuan Province; four regions; contribution rate method; ET0;
Abstract: FAO-56Penman-Monteith method was used to estimate the monthly potential evapotranspiration(ET0)from 1960 to 2010in four different regions of Sichuan Province.Then the causes for ET0 change in recent 50 years were analyzed by contribution rate method.Results show that in the whole province,Sichuan basin and mountainous area around basin,the negative contribution of decreased sunshine duration and wind speed to ET0 is greater than the positive contribution of increased average,maximum,minimum temperature and decreased relative humidity to ET0,which causes ET0 to decrease.While in northwest Sichuan plateau the positive contribution of upward average,maximum,minimum temperature and downward relative humidity to ET0 exceeds the negative contribution of downward sunshine duration and wind speed,inducing ET0 to increase.In mountainous area of southwest Sichuan the negative contribution of decreased average,minimum temperature,sunshine duration and wind speed to ET0 exceeds the positive contribution of increased maximum temperature and decreased relative humidity,resulting in decline of ET0.The decreased sunshine duration in the whole province and Sichuan basin and the decreased wind speed in mountainous area around basin and mountainous area of southwest Sichuan are the primary contributors to ET0 decrease,respectively.The increased ET0 in northwest Sichuan plateau is mainly attributed to the increased minimum temperature.