Study On Water Consumption Law And Irrigation Scheduling Of Turfgrass In Tianjin Seashore Region

This study is a part of 863 Program"water saving irrigation technique system and demonstration in urban green space of semi-arid North of China"(2002AA2Z428111).In Tianjin seashore region, the evapotranspiration(ET), appearance quality and growth index of Tall fescue and white clover has been studied in 4 different irrigation treatments (W1:100%W～75%W; W2:100%W～60%W; W3:100%W～45%W; W4:100%W～moisture lower limit. W: field moisture capacity). The measurement of turfgrass soil water content with neutron probe has been studied, the soil moisture dynamics can be educed. We can submit a fit turf irrigation schedule to provide theoretic basis of turf scientific irrigation.Except May and November,the difference among the treatments of tall fescue is significant (P<0.05). The difference among the treatments of white clover is very significant (P<0.01).Under four different irrigation treatments, the tendency of the ET change is conformable, which changes along with season.The tall fescue soil water profile in 0～100cm can be divided into 3 layers, i.e., active layer (0～30cm), hypoactive layer(30-50cm) and correspondingly sTab. layer(50-100). Scheming wetted soil layer depth is 50cm, the most irrigation quota 44.23mm/time.The white clover soil water profile in 0～100cm can be divided into 2 layers, i.e., active layer (0～60cm), correspondingly sTab. layer(60-100). Scheming wetted soil layer depth is 60cm, the most irrigation quota 70.77mm/time.Appearance quality, photosynthesis and transpiration rate, chlorophyl content, clipping and clipping water content of tall fescue and white clover increase along with irrigation treatments, so as to root total and active absorption area, but the root activity decrease under exorbitant irrigation. Analyzing integration influence of turfgrass in different irrigation treatments, we ascertain W2 as the best irrigation treatment of tall fescue,W3 as the best irrigation treatment of white clover. The ET change of them is the benchmark of submitting the irrigation scheduling.In irrigation treatments of W2 and W3, In growing season the total ET of tall fescue is 1015.91mm, the total rainfall is 477.6mm, effective rainfall is 367.5mm,winter irrigation and green return irrigation 90mm and 14154mm, in this region the whole year net irrigation quota of tall fescue is 738.41mm, 22 times, white clover, 1830.3mm, 26 times.