| The influence of the regulation of greenhouse humid and hot environment on crop physiological ecology,water consumption process,yield,quality and other indicators can not be ignored.The study on the influence of different states of vents and different irrigation amounts on the changes of indicators can further improve the theory of greenhouse environmental regulation and realize the high-efficiency utilization of water resources.This study is based on the National Natural Science Foundation Project “study on the interaction mechanism between the transpiration of Tomato under mulch drip irrigation and the humid and hot environment of greenhouse”(51709110),which is supported by the tutor.This study takes drip irrigation of Tomato under the film as the research object in North China.Three ventilation modes were set up: opening North window and top window(T1),simultaneously opening North window,south window and top window(T2),opening North window and south window(T3)and reference 20 cm standard evaporating dish,three water treatments were set up: 0.9Ep(W1),0.7Ep(W2)and 0.5Ep(W3).The effects of different ventilation modes and water treatment on the spatial and temporal characteristics of indoor humidity and heat environment,physiological and ecological characteristics of tomato,water consumption and yield of tomato were studied.The results show that:(1)Under different weather conditions,the daily variation characteristics of wind speed of different ventilation are significantly different.In cloudy days,the wind speed of T2 is the most obvious.From 10:00 to 18:30,the average wind speed was about 0.4 m/s,and the max wind speed was 0.449 m/s.The change range of T1 and T3 is smaller than that of T2,ranging was 0.05 m/s ~ 0.25 m/s;the wind speed of T2 is the largest at about 11:15 in sunny days,which was 1.239 m/s,and the change trend is also more obvious than T1 and T3.In the flowering and fruit setting stage,the wind speed of T1 and T3 was similar,the range of variation was 0.05 m/s ~ 0.2 m/s,and that of T2 was 0.1 m/s ~ 0.45 m/s.During the mature picking period,the wind speed of three ventilation varied greatly.The wind speed of T1 ranged was 0.05 m/s ~ 0.16 m/s,T2 was 0.07 m/s ~ 0.65 m/s,T3 was 0.04 m/s ~ 0.26 m/s.Ventilation is another main factor affecting the evaporation of water surface besides solar radiation.Under the same weather conditions,T2 has a significantly higher evaporation of water surface.(2)The combined control of ventilation and water has great influence on the temporal and spatial variation of air temperature and humidity in greenhouse,and the diurnal variation characteristics of air temperature and humidity are quite different at 30 cm and 2 m above the canopy under different weather conditions.On cloudy days,the difference of temperature and humidity between T1 and 2 m at night is the largest,with the maximum temperature difference of about 0.6 ? and the maximum humidity difference of about 4 %;on daytime,the difference of temperature and humidity between 30 cm and 2 m above T3 is the largest,with the maximum temperature difference of about 2.5 ? and the maximum humidity difference of about 9.5 %;on sunny days,the difference of temperature and humidity between30 cm and 2 m above T3 at night is the largest,with the maximum temperature difference of1 ?.In daytime,the temperature difference between 30 cm and 2 m above T2 canopy is the largest,the maximum temperature difference is about 1.5 ?,the humidity difference is the smallest,the maximum difference is about 16 %.(3)In the whole growth period,there is little difference between the canopy temperature of three ventilation modes and that of 2 m,which are gradually increasing.The temperature of2 m is higher than that of the canopy,and the temperature change of T2 mode is the most obvious,the maximum temperature difference is 1.5 ?;during the whole growth period,the canopy humidity of T1 treatment was more than 2 m,and the maximum difference was 4.2 %;at the stage of flowering and fruit setting,the humidity at 2 m of T2 treatment was higher than that of canopy,and the maximum difference was 1.5 %,while at the stage of mature picking,the humidity at 2 m of T2 treatment changed greatly,and the maximum difference was 6.2 %;in the whole growth period of T3 treatment,the humidity at 2 m was higher than that of canopy,and the maximum difference was 4 %;the influence of water content on the characteristics of canopy temperature and humidity is also greater,but the influence of water content on the characteristics of canopy temperature and humidity at 2 m is less than that of ventilation.(4)In different growth stages,the change of soil temperature and humidity in different depth is most affected by water treatment,but less affected by ventilation.The soil temperature of 0.9Ep is relatively high at 0 ~ 10 cm,the soil humidity of 10 ~ 20 cm is relatively high at 0.7Ep and 0.5Ep,and the soil temperature of 10 ~ 20 cm is relatively high at30 ~ 40 cm;when the soil temperature is high,the soil humidity is not low,and the soil temperature and humidity of high water is not completely higher than that of low water.(5)In the whole growth period,T3 had the highest plant height and T2 had the largest leaf area under 0.9Ep treatment.Under 0.7Ep treatment,the plant height of T1 was the highest,the leaf area was T3 > T2 > T1 at flowering and fruit setting stage,and T1 > T2 > T3 at mature picking stage.Under 0.5Ep treatment,the plant height and leaf area of tomato were T3 > T2 > T1 at flowering and fruit setting stage,and T3 > T1 > T2 at mature picking stage.The effects of different water treatments on the characteristics of morphological indexes and spatial distribution of tomato roots were significant.The root length and soil depth met the quadratic regression function model,R2 was above 0.74,and the correlation was high.Atdifferent growth stages,the combined regulation of different ventilation and water has a greater impact on the photosynthetic rate,stomatal conductance and transpiration rate.(6)The effects of different ventilation and moisture on total yield,fruit quality,ETa,WUE and IWUE were significant.At 0.9Ep,T1 treatment has high total yield,low water consumption and high water use efficiency;at 0.7Ep,T2 treatment has high total yield,low water consumption and high water use efficiency;at 0.5Ep,T3 treatment has high total yield,low water consumption and high water use efficiency.T1 ventilation and 0.9Ep water combination,T2 ventilation and 0.7Ep water combination,T3 ventilation and 0.5Ep water combination had better fruit quality.(7)In the whole growth stage,the change range of transpiration of three ventilation modes under the same water treatment is quite different;but under the same ventilation mode,the change rule of transpiration of Tomato under different water treatment is basically the same,which is W1 > W2 > W3,and based on MATLAB,the transpiration law of greenhouse tomato was simulated and the relationship between transpiration and air temperature and humidity was simulated.It was found that the simulation effect of the three regression function model was better,R2 was above 0.61,SSE was within 11.35,RMSE was within 1.55,and the simulation effect of 0.7Ep water treatment in T2 ventilation mode was the best,R2 was 0.9640,correlation was high,SSE was 1.3650,RMSE was 0.5225,and the test effect was better. |
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