Studies On Transpiration Charactcristics Of Three Turfgasses

In this paper, take three kinds of tall fescue lawn:Tall fescue (Festuca arundinacea):ryegrass (Lolium perenne):hard fescue (Hard Fescue)=5:3:2, tall fescue (Festuca arundinacea):Kentucky bluegrass (Poa pratensis)=4:1and Tall fescue unicast as the reseach object. In the conditions of full irrigation and limit irrigation, measures on the evapotranspiration and different growth and physiological indicators of three lawn in the whole growing season, and works out the optimum irrigation program of the three lawn in Qingdao area.The results are as follows:(1)The maximum evapotranspiration under full irrigation of three lawn in the whole growing season is734.21mm,764.08mm,770.96mm; the mminimum evapotranspiration under limit irrigation is444.62mm,41.87mm,562.83mm; the water-saving potential of three lawn expresses as:T1(289.59mm/season)>T2(222.21mm/season)>T3(208.13mm/season), T1lawn has the best water-saving potential.(2)The daily evapotranspiration change of three lawn under two water conditions shows a single peak curve, and the maximum evapotranspiration appears in the12:00-14:00period. The variation of monthly evapotranspiration rate of three lawn is basically the same, the summer evapotranspiration rate is greater than the spring and autumn, belongs to summer water-consumption type; The evepotranspiration rate between the two water conditions is significantly different (P<0.05), expresses as:full irrigation group> limmit irrigation group; The average evapotranspiration rate in the same water condition is different (P<0.05), performances as:T3> T2> T1.(3)In the condition of full irrigation, the evapotranspiration of three lawn in sunny is3.82mm/d(T1),6.89mm/d(T2),6.93mm/d(T3), and1.22mm/d(Tl),1.04mm/d(T2),2.55mm/d(T3) in cloudy day, evapotranspiration difference between sunny and cloudy performenced as:T2>T3>T1; In the condition of limit irrigation, the evapotranspiration of three lawn in sunny is2.25mm/d(T1),3.63mm/d(T2),3.81mm/d(T3), and1.04mm/d(T1),2.08mm/d(T2),2.14mm/d(T3) in cloudy day, evapotranspiration difference between sunny and cloudy performences as:T3>T2>T1, the two lawn of T2and T3influenced by weather is more obvious.(4)The analysis of growth and physiological indicators shows that:The regeneration rate of three lawn in different months is significantly different, June to September has the fastest growth. Generally, the regeneration rate of full irrigation group is larger than the limit irrigation group. As the stress time, the appearance quality of the three lawn gradually decreased, soil moisture content and lawn appearance shows a significant positive correlation; The leaf water content, chlorophyll content and root activity indicators all gradually decreased as the stress time, and T3has the largest decline, then T2, and T1lawn shows the best drought resistance.(5)The irrigation system of three lawn throughout the whole growing season is as follows:the total irrigation of T1lawn is540mm, and17iriigation times; the total irrigation of T2lawn is648mm, and20iriigation times; the total irrigation of T1lawn is684mm, and21iriigation times.