| The method of field test combining with model simulation is used to study on growth and developmental characteristics, water transport mechanism and characteristics of evapotranspiration of adult instar seedless white grape in this paper.The results are as followed:The determination results of soil water content and physiological growth index in test yield show that:The watering effects of seven different irrigation quotas in order from good to poor is:middle water, high water, the third combination, the second combination,the first combination,low water and the control group,by compared comparison of plant growth,photosynthetic characteristics,fruit quality and yield taken the ultimate production benefit as principle.The change of SPAC water potential spatial-temporal variability in vineyard is significantly,and the effects in water potential of all kinds of mediums. As the increasing of the irrigation quota,the SPAC water potential gradient increases,the SPAC adjacent interface water potential difference improves,the SPAC water movement increases,and the water potential difference between soil and leaves,leaves and atmospheric, atmospheric and soil increases.The SPAC migration driving force is increasing, and the water potential difference between soil and leaves,between leaves and atmospheric and between atmospheric and soil are increasing at the same time.In the continuum, the maximum of soil resistance is about1425.66times than the minimum,the maximum of flow resistance is about3.08times than the minimum,and the maximum of leaves-atmospheric system flow resistance is about3.08times than the minimum. In all kinds of flow resistances,the leaves-atmospheric system flow resistance is the biggest,accounting for98.78%-98.98%in total flow resistance,the flow transport resistance takes the second place,accounting for1.02%-1.21%,and the soil resistance is the smallest,the proportion in all kinds of flow resistances can be neglectedThe difference of daily mean soil surface evaporation between water treatments is relatively small when leaf area index<3,the daily mean soil surface evaporation between treatments is increasing as the LAI increased.The daily accumulated soil surface evaporation of high,middle and low treatments are respectively showed:221.77151.67and129.86mm.The total evaporation are567.7mm,480.6mm,467.2mrn,412.2mm taken a view from miniature evaporation pan and water surface evaporator,and ETo daily variation regularity in test stage.The water consumption in ach growth period of grape has little difference and the tends to be uniform.In germination stage,the water consuming intensity is3.2-4.7mm/d;in leaf-expansion period,7.3-9.8mm/d; in florescence,5.6-6.6mm/d;in fruit expanding process,6.6-8.4mm/d;and in fruit maturation period,5.4-6.7mm/d.The size order of different water consumption from top to bottom is:the furrow irrigation control group,high water,middle water,low water.In the main growth period of grape,the transpiration is the main way of water consumption,manifested as:in germination stage,the transpiration intensity is1.49-2.49mm/d;in leaf-expansion period,5.74-6.83mm/d;in florescence,2.73-4.55mm/d;in fruit expanding process,6.09-6.55mm/d; and in fruit maturation period,4.39-5.01mm/d.Through the comprehensive contrast analysis of physiological and evapotranspiration characteristics, the drip irrigation technique parameters followed are suggested:(1)The second combination:three-pipe surface arrangement, a drip irrigation tape is placed40cm from main root in cultivation ditch, and another two drip irrigation tapes are placed20and60cm from main root in cultivation ridge. The dripper discharge is2.7L/h;(2)High water:three-pipe surface arrangement, and the technical parameters are the same as the second combination;(3)Middle water:three-pipe surface arrangement, and the technical parameters are the same as the high water,irrigation quota of the three water treatments were700,1085and6303/mu.The net income of middle water arrangement is the highest. |
