Researching Into The Problems Of The Irrigation Water's Optimal Allocation In Yangzhou Along The Canal Irrigation District

Yangzhou along the Canal Irrigation District is located in the East Route in South-North Water Diversion Project,The main irrigation water source is canal water.Irrigation water plan is generally considered the multi-year average,While rice irrigation water consumption is closely related to rainfall and evaporation,but it has a large random,interannual changes larger.So there is a big contradiction between irrigation annual water plan and irrigation water of rice.Rice annual irrigation water has a great change.Due to the characteristics of water transfer project,it's not possible to carry out the allocation of water during the year according to the actual irrigation water consumption of rice.There are also some contradictions between the water demand and water use plan in the irrigation area.The water level in Lixiahe Area is low,there are quite a part of the area under del2.5 m,pumping river water from 8.5m to 2.5m through Jiangdu pumping station,There is serious waste of water resources and electricity.By researching the problems of optimal allocation of the water use in Yangzhou along the Canal Irrigation District,to provide a reference for scientific adjustment of water resources and optimize the irrigation water use plan,and ensuring the normal water supply of the South-to-North Water Diversion Project and the normal water demand.This paper focuses on the variation characteristics of net irrigation water use and the effect of the change of irrigation area on irrigation water,the main results are as follows:(1)According to the "? value method",calculate the daily water requirement of rice,using rice irrigation quota calculation model to calculate the rice's irrigation quota,Comparing with the date of current year,adjusting and determines model parameters using a single variable,calculate rice irrigation quota over the years,ensure the irrigation quota for dry years is 569.26 m3/mu.(2)Analysis of interannual change of rainfall evaporation and variation characteristics of rice net irrigation requirement using SPSS Statistical Software,It was determined that the rainfall in Yangzhou along the irrigation area during 1966?2016 showed a slight decrease trend,year evaporation showed a significant downward trend,the annual change of net irrigation water use rate showed a slight upward trend.This paper argues that rainfall and evaporation are the main influencing factors of net irrigation water consumption,and the rainfall and net irrigation water consumption has negatively correlated,and evaporation has positively correlated,according to both of tow can effectively predict the annual variability trend of rice net irrigation consumption.(3)Using the calculation model of irrigation water consumption of different irrigation areas with different irrigation area to ensure that the relationship between the reduction of irrigation area and the amount of irrigation water was negatively correlated.On this basis,compile irrigation tail cut irrigation area calculation model of irrigation water use,provides the reference for adjusting the water in Lixiahe Area.(4)Adjust the irrigation area of the tail of the ground elevation in del 2.5 m below,supplying water by the Jiangdu pumping station irrigation area.Regarding drought year as representative year,the irrigation water consumption calculation model was used to analyze the change of irrigation water consumption,pumping station energy consumption and pumping cost in the typical trunk canal before and after the water source adjustment project was carried out.