Law Of Transpiration And Water Consumption In Apple Orchard In Shandong Hilly Area

The study on water consumption of the whole tree has always been a common issueconcerned by physiologists, ecologists, foresters. This problem is not only the core of treewater physiology, but also one of the theoretical bases throughout the entire forest ecosystemand forest cultivation. In recent years, with the structure adjustment of agricultural planting,the increasing area of the fruit planting and orchards’ inputs and outputs, the waterconsumption of orchards is increasing. Therefore, cognize the law of fruit tree transpirationand accurate determination of fruit tree’s transpiration, understand the dynamic of the orchardsoil is beneficial to establishing reasonable irrigation system to ensure that the water saving,high yield, stable yield and can be suitable for orchard water-saving.Taking apple orchard of hilly area in Shandong as the study object, some research resultshas been made, through system test research and simulation on transpiration features of Appleleaves, climate changes of orchard, trunk sapwood liquid flow of spatio-temporal changes law,dynamic changes trend of soil water and the Space-time Variation Regularities of Soil WaterSurplus or Lack of the orchard, using Thermal Dissipation Sap Flow Probe portablephotosynthesis system plant canopy analyzer TRIME-FM soil profile moisture measureportable-meteorological station in the high-quality red Fuji apple orchards in Chaoquantown,Feicheng city, Shandong province during2009-2010.（1） The peak of transpiration comes early in summer and a late in spring, early summerand autumn. Highest transpiration intensity comes in early summer, then gradually decreasing.The annual variation of day average transpiration rate of Red Fuji vane showed a single peaktrend. The max peak value is2.726mmol.m^-2·s（-1） in July15, the mix0.5876mmol.m^-2·s（-1） inNovember16, a difference of2.139mmol.m^-2·s（-1）.The order from largest to smallest ofaverage daily transpiration rate of Red Fuji leaves is June> July> August> April> May>September> October>November.Transpiration rate of different orientation of Red Fuji apple is different. The descendingorder is west, south, east and north. Except for the few days, the leaf transpiration rate ofdifferent direction is not significant. The leaf transpiration rate trend of different orientationhas different characteristics in different periods.It is different between environmental factors in different date and the relevance andimportance of the transpiration rate. But PAR and transpiration rate showed a significant and extremely significant correlation. From the point of view throughout the entire growingseason, it is significantly correlated between transpiration rate and atmospheric temperature,PAR, GS, CI. PAR and transpiration rate correlation reached0.689.（2） Transpiration rate of detached leaf is1.07³.44times of living leaves, an averageof1.45times. That is to say, the maximum potential transpiration rate is1.45times of thestate of nature. The ratio of the porometer method and gravimetric method show a decreasingtrend in daily course, while the correction factor gradually increasing. The correction factorsin daily course are0.24,0.32,0.71,0.83,0.88,1.00, an average value of0.495. Departuredegree of the measured results by Porometer method shows maximum in the early morningduring daily periodicity and decreased over time. It deviates from4.24³.11times during6:00¹0:00,1.40¹.14times during10:00¹4:00,1.20¹.00times during14:00¹8:00, anaverage of2.02times in the growing season. The leaves transpiration rate is9213kg aftercorrection in growing season with porometer measurements.（3） Trunk sapwood liquid flow flux density shows a single trend in dailycourse. Change of trunk sap flow in daily course shows a single peak curve in clear day, abimodal curve in overcast day, a multi peak curve in rainy day during growing season inJuly.It is on clear day that the sap flow velocity significantly correlated with PAR, since thecorrelation is influenced by atmospheric temperature on overcast and rainy day. Throughoutthe growing season, the month mean values of sapwood liquid flow flux density showed thatJuly>June>May>August>September>October>AprilThe model for the daily course of sapwood liquid flow flux density is W=33.573(1-1（-30.588） e^-0.395t)^{1/（-0.405）}，R²=0.99, perfect fitting effect,basing on the Richards model.Sap flux density lag behind environmental factors, but the time is different in one day.The lag time of different seasons has certain regularity on the whole, which is different withdifferent environmental factors. Related to atmospheric temperature and atmospheric relativehumidity, sap flux density shows a delay phenomenon. The annual change law of lag timeshows a tendency that increases first and then decreases gradually. The maximum appears inMay and June, the minimum in September. Related to soil temperature, the annual change lawof sap flux density shows a positive number and then a negative number, with a tendencydecrease first and then increase gradually. Related to wind speed and soil water content thetendency increase first then decrease gradually and increase again, Related to PAR increasefirst and then decrease gradually. The maximum monthly averaged values of lag time are both12min in June and July. Minimum appears in September, is-24min. Related to environmental factors，Lag Time of Sap flux density are different between deferent trees, except atmospherictemperature，differences of lag time is not significant.（4） Red Fuji apple’s transpiration rate is determined by TDP, maximum is in July,the rateis101.75㎜and daily average is3.28㎜, minimum is in April the rate is29.52㎜and dailyaverage is0.99㎜. In growing season, transpiration rate of the Red Fuji apple orchard is682.6㎜, and July is the maximum, the rate is137.19㎜, October is the minimum, the rate is44.95㎜. The rate in the whole growing season shows a tendency which increase first thendecrease. Apple trees’ transpiration rate takes two-thirds of whole orchard; ground surfaceflux takes one-thirds. Ground surface flux rate takes highest of orchard is in spring, especiallyin April, it is about70%, and in May it is about50%. Rainfall of the orchard in the wholegrowing season is598.1㎜, water deficit is84.5㎜.Transpiration rate of the orchard in growing season is714.27㎜determined by PenmanMethod, maximum is in June, water deficit of the orchard is116.17㎜. Useing PenmanMethod to improve stem-flow gauge, the transpiration rate of the orchard in growing season is612.6mm, whole water deficit is14㎜（5） The apple orchard’s moisture content has a significant difference in different depth,with the increase of soil depth, soil moisture content increased gradually. Straw-mulching canimprove soil water content in the layers of below60cm, but reduce soil water content in thelayers of60-80cm. The analysis shows that straw-mulching only obviously affected the soilwater content in the layers of10-20cm and0-80cm by straw-mulch.