Stanghellini model is one of the few models primarily developed to predict the evapotranspiration of crops(ET_(c))in naturally ventilated greenhouses.However,there are insufficient data on the model regarding its use,...Stanghellini model is one of the few models primarily developed to predict the evapotranspiration of crops(ET_(c))in naturally ventilated greenhouses.However,there are insufficient data on the model regarding its use,particularly in China where solar greenhouses without heating systems are fast spreading for vegetable growth and production.The application of Stanghellini model and the evaluation of its performance using meteorological and tomato plant data generated inside an unheated and naturally ventilated multi-span Venlo-type greenhouse is exploited in this study.Model capability was evaluated by utilizing data from sap flow measurements,meteorological and crop data.Measured meteorological data included solar radiation(R_(s)),air temperature(T_(a)),relative humidity(RH)and net radiation(Rn).Average leaf area index(LAI)values measured during the experimental period were 1.00,3.30,4.05 and 2.93;while determined crop coefficients(K_(c))changed from 0.40,0.62,1.12 to 0.83 for the initial stage,development stage,mid-season stage and late-season stage,respectively.Results from the study indicated that the average hourly ET_(c) values of tomato plants using sap flow measurements were 0.165 mm/h,0.148 mm/h,0.192 mm/h and 0.154 mm/h for the initial stage,development stage,mid-season stage and late-season stage,respectively.Meanwhile,the ET_(c) values obtained from calculation using Stanghellini model were 0.158 mm/h,0.152 mm/h,0.202 mm/h and 0.162 mm/h for the initial stage,development stage,mid-season stage and late-season stage,respectively.These ET_(c) values calculated by the Stanghellini model were close to the measured values within the same period.The coefficients of correlation(R^(2))based on hourly ET_(c) for the calibration data was 0.94 and that of the validation dataset was 0.90.Scatter plots of the estimated and measured hourly ET_(c) revealed that the R^(2) and the slope of the regression line for May,June and July were 0.94,0.90,0.96 and 1.15,0.97,1.10 respectively.These data were well represented around the 1:1 regression line.A model sensitivity analysis carried out illustrates how the changes in R_(s) and T_(a) affect greenhouse ET_(c).Stanghellini model was therefore proven to be suitable for ET_(c) estimation with acceptable accuracy in unheated and naturally ventilated greenhouses in the Northeast region of China.展开更多
Domestication of plants by man through greenhouse crop production has revolutionized agricultural farming systems worldwide.Selecting the appropriate greenhouse technology together with the user-friendly evapotranspir...Domestication of plants by man through greenhouse crop production has revolutionized agricultural farming systems worldwide.Selecting the appropriate greenhouse technology together with the user-friendly evapotranspiration(ETc)model can optimize crop water use.The greenhouse microclimate environment has nearly zero wind speed and low radiation,hence low transpiration due to high temperature and humidity.Therefore,matching the greenhouse microclimate with the appropriate ETc model will certainly optimize crop water use efficiency since water is becoming a scarce resource globally,more so in the greenhouse environment.This is one of the main reasons why the gap between the dissemination of various advanced ETc models and the application by the greenhouse crop producers’community needs to be bridged.The likelihood or chances of rapidly disseminating and adopting advances in ETc estimating technology by a larger greenhouse crop producers community will increase if greenhouse ETc models become more user-friendly and available.The contribution of the greenhouse system to increased and sustainable food production must come through improved disseminating,adopting and use of existing greenhouse ETc models.FAO recommends a standard approach for the determination of crop water requirements utilizing the product of reference evapotranspiration(ET0)and crop coefficient(Kc)values.The FAO approach can also be used in greenhouse cultivation systems.However,studies connecting greenhouse technologies and methodologies for measuring ET0 or ETc in greenhouses are not available.There are also few studies undertaken that compared the performance of ET0 or ETc models under different categories of greenhouse conditions.In this review,a link between greenhouse technology and ET0 model or ETc model,and how existing knowledge and methodologies in ET0 or ETc measurements can actually enhance the sustainability of greenhouse farming have been highlighted.The categories of greenhouses,equipment commonly used,and the data collected for ET0 and ETc measurements have been established in the article.This review aimed to evaluate and summarize ET0 and ETc models currently available and being used in the various greenhouse categories.The accuracy assessment levels of the ET0 models about the category of the greenhouse microclimate environment were carried out.展开更多
基金This study has been financially supported by the National Key Research and Development Program of China(grant number 2016YFA0601501,2016YFC0400104)the Natural Science Foundation of China(51509107,51609103)+1 种基金Natural Science Foundation of Jiangsu province(BK20150509)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Stanghellini model is one of the few models primarily developed to predict the evapotranspiration of crops(ET_(c))in naturally ventilated greenhouses.However,there are insufficient data on the model regarding its use,particularly in China where solar greenhouses without heating systems are fast spreading for vegetable growth and production.The application of Stanghellini model and the evaluation of its performance using meteorological and tomato plant data generated inside an unheated and naturally ventilated multi-span Venlo-type greenhouse is exploited in this study.Model capability was evaluated by utilizing data from sap flow measurements,meteorological and crop data.Measured meteorological data included solar radiation(R_(s)),air temperature(T_(a)),relative humidity(RH)and net radiation(Rn).Average leaf area index(LAI)values measured during the experimental period were 1.00,3.30,4.05 and 2.93;while determined crop coefficients(K_(c))changed from 0.40,0.62,1.12 to 0.83 for the initial stage,development stage,mid-season stage and late-season stage,respectively.Results from the study indicated that the average hourly ET_(c) values of tomato plants using sap flow measurements were 0.165 mm/h,0.148 mm/h,0.192 mm/h and 0.154 mm/h for the initial stage,development stage,mid-season stage and late-season stage,respectively.Meanwhile,the ET_(c) values obtained from calculation using Stanghellini model were 0.158 mm/h,0.152 mm/h,0.202 mm/h and 0.162 mm/h for the initial stage,development stage,mid-season stage and late-season stage,respectively.These ET_(c) values calculated by the Stanghellini model were close to the measured values within the same period.The coefficients of correlation(R^(2))based on hourly ET_(c) for the calibration data was 0.94 and that of the validation dataset was 0.90.Scatter plots of the estimated and measured hourly ET_(c) revealed that the R^(2) and the slope of the regression line for May,June and July were 0.94,0.90,0.96 and 1.15,0.97,1.10 respectively.These data were well represented around the 1:1 regression line.A model sensitivity analysis carried out illustrates how the changes in R_(s) and T_(a) affect greenhouse ET_(c).Stanghellini model was therefore proven to be suitable for ET_(c) estimation with acceptable accuracy in unheated and naturally ventilated greenhouses in the Northeast region of China.
基金supported by the Natural Science Foundation of China(Grant No.4186086351509107+6 种基金51609103)the National Key Research and Development Program of China(Grant No.2021YFC32011002017YFA0605002)the Beltand Road Special Foundation of the State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering(Grant No.2020nkzd01)the Postdoctoral Research of Jiangsu Province(Grant No.Bs510001)the Open Fund of High tech Key Laboratory of Agricultural Equipment and Intelligentization of Jiangsu Province(Grant No.JNZ201917)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘Domestication of plants by man through greenhouse crop production has revolutionized agricultural farming systems worldwide.Selecting the appropriate greenhouse technology together with the user-friendly evapotranspiration(ETc)model can optimize crop water use.The greenhouse microclimate environment has nearly zero wind speed and low radiation,hence low transpiration due to high temperature and humidity.Therefore,matching the greenhouse microclimate with the appropriate ETc model will certainly optimize crop water use efficiency since water is becoming a scarce resource globally,more so in the greenhouse environment.This is one of the main reasons why the gap between the dissemination of various advanced ETc models and the application by the greenhouse crop producers’community needs to be bridged.The likelihood or chances of rapidly disseminating and adopting advances in ETc estimating technology by a larger greenhouse crop producers community will increase if greenhouse ETc models become more user-friendly and available.The contribution of the greenhouse system to increased and sustainable food production must come through improved disseminating,adopting and use of existing greenhouse ETc models.FAO recommends a standard approach for the determination of crop water requirements utilizing the product of reference evapotranspiration(ET0)and crop coefficient(Kc)values.The FAO approach can also be used in greenhouse cultivation systems.However,studies connecting greenhouse technologies and methodologies for measuring ET0 or ETc in greenhouses are not available.There are also few studies undertaken that compared the performance of ET0 or ETc models under different categories of greenhouse conditions.In this review,a link between greenhouse technology and ET0 model or ETc model,and how existing knowledge and methodologies in ET0 or ETc measurements can actually enhance the sustainability of greenhouse farming have been highlighted.The categories of greenhouses,equipment commonly used,and the data collected for ET0 and ETc measurements have been established in the article.This review aimed to evaluate and summarize ET0 and ETc models currently available and being used in the various greenhouse categories.The accuracy assessment levels of the ET0 models about the category of the greenhouse microclimate environment were carried out.
