Water Saving Irrigation Schedule Of Urban Green

Urban grass is an important part of urban ecology and landscape,which plays a positive role in residents’leisure and improving their quality of life.With the construction of ecological civilization and the increase of green space area,the intensity of urban greening is gradually strengthened,the urban water consumption is also increased,and the shortage of water resources is becoming more and more serious.At present,the irrigation level of urban gr0 is generally not high,most of them still take artificial sprinkling as the main irrigation mode,the utilization rate of water resources is low and the waste is serious,so it is urgent to improve the irrigation technology and water saving level of urban grass.In the water-saving garden of Xiqing District,Tianjin,the typical green plant of Tianjin was selected to carry out the experiment.Three different soil moisture control indexes（75%,60%,45%field water holding capacity）were used for irrigation treatment.The evapotranspiration of tall fescue lawn under different irrigation treatment was measured by small evapotranspiration meter,the growth and development,appearance quality and physiological index of lawn were evaluated,the water consumption law and suitable irrigation scheme of high fescue were explored,and the irrigation system of high fescue was worked out.The main findings are as follows:With the increase of irrigation amount,the evapotranspiration of tall fescue lawn increased,and the difference of water condition had great influence on the evapotranspiration of lawn.After three kinds of irrigation treatment,the evapotranspiration of tall fescue was basically the same,and the water consumption was concentrated in summer and autumn,and the sum of evapotranspiration in April to September accounted for 86.2%of the total evapotranspiration in the whole growth season.Evaporation was 1134.32 mm、1037.28mm、932.70mm.The quality of green space is closely related to the amount of irrigation.The appearance quality index and ecological quality index of lawn decreased with the decrease of irrigation water.In the three irrigation schemes,too little irrigation will make the apparent quality of lawn worse,and too much irrigation will cause the waste of water resources,so the suitable irrigation scheme should meet the dual requirements of saving water resources and greening lawn.Based on the measured data of evaluation index,three irrigation schemes were evaluated by grey weighted clustering evaluation method.Under the experimental conditions,the optimum irrigation scheme of tall fescue W₂,corresponding grassland irrigation system are:irrigation quota 26.61 mm（17.75m³/mu）,irrigation times 26 times,irrigation quota 761.86 mm.In practical application,it can be adjusted according to different level years and actual rainfall.This experiment proves that lawn has great water-saving potential and has strong novelty in the selection of research object,systematicness of research and the combination of theory and production practice.At the same time,the green space adopts the form of sprinkler irrigation and micro-spray irrigation,which can save water by 30%and 80%,and has good landscape effect.