局部湿润模型模拟南疆滴灌枣园蒸散量及蒸腾量适用性研究

为构建适用于模拟南疆滴灌成龄枣园蒸散及其组成成分的模型，了解枣园土壤蒸发特征，本研究在双源模型和局部湿润灌溉方式下稀疏植被蒸散估算模型基础之上构建滴灌枣园局部湿润模型，以涡度相关法实测2017年枣园蒸散数据，对双源模型（Shuttleworth-Wallace）及滴灌枣园局部湿润模型（Partial Root-zone Irrigation model）系数进行拟合；之后通过评价两种模型模拟值的可靠性以及增加和减少模型参数10%来观测模型各参数对蒸散的影响方式，并校验各模型参数计算公式的准确性；然后以涡度相关法与液流法实测的2018年枣园蒸散与蒸腾量为基准值，对双源模型与滴灌枣园局部湿润模型模拟2018年枣园蒸散及蒸腾量的可靠性进行评价，筛选出适合模拟南疆滴灌枣园蒸散及其组分的模型并模拟滴灌枣园土壤蒸发特征。结果表明：滴灌枣园局部湿润模型和双源模型的模型系数拟合准确；依据模型模拟评价标准，两种模型模拟2018年枣园蒸散的结果均为极好，且精度基本一致。滴灌枣园局部湿润模型模拟蒸腾量结果良好，与实际测定值之间的差值为15.73 mm；双源模型模拟蒸腾量结果不可取。因此筛选出滴灌枣园局部湿润模型模拟枣园土壤蒸发，枣园土壤蒸发量占蒸散量的19.74%。滴灌枣园局部湿润模型可以准确估算滴灌成龄枣园蒸散及蒸散组成成分。

Applicability of Partial Root-zone Irrigation model to simulate evapotranspiration and transpiration in drip irrigation jujube orchards in southern Xinjiang

Constructing a model suitable for simulating evapotranspiration and evapotranspiration components of mature jujube orchard under drip irrigation in southern Xinjiang and understanding their soil evaporation characteristics would be beneficial for growers. Based on the Shuttleworth-Wallace model and the evapotranspiration estimation model of sparse vegetation under local wet irrigation, a Partial Root-zone Irrigation model of drip irrigation for the jujube orchard was constructed. The evapotranspiration data were measured by eddy correlation methods in the jujube orchard in 2017, and the coefficients of the Shuttleworth-Wallace model and the Partial Root-zone Irrigation model of drip irrigation for jujube orchard were fitted and evaluated; the effects of the model parameters on evapotranspiration were observed by increasing and decreasing the model parameters by 10%, and the accuracy of the formulas for calculating the parameters of each model was verified. Evapotranspiration was then measured using the eddy correlation method and transpiration was measured using the liquid flow method to obtain accurate values. The reliability of the two models used to simulate evapotranspiration and transpiration in jujube orchard in 2018 were evaluated. The models were suitable for calculating evapotranspiration and evapotranspiration components in the drip irrigation jujube orchard of southern Xinjiang in 2018, as well as simulating the soil evaporation characteristics. Model coefficients of the Shuttleworth-Wallace model and Partial Root-zone Irrigation model for the drip irrigation jujube orchard were accurately fitted according to the criteria for evaluating the simulation results of the model. The results of the two models for simulating evapotranspiration were excellent for the jujube orchard in 2018, and the accuracy of the two models were the same. The results of the Partial Root-zone Irrigation model for drip irrigation jujube orchard were also good, with a difference of 15.73 mm between the model and actual measured value. It was not advisable to simulate transpiration by using the Shuttleworth-Wallace model. Therefore, the Partial Root-zone Irrigation model for drip irrigation was selected to simulate soil evaporation in the jujube orchard, and the results showed that soil evaporation accounted for 19.74% of the evapotranspiration. Thus, the Partial Root-zone Irrigation model for the drip irrigation jujube orchards can be used to accurately estimate the evapotranspiration and evapotranspiration components of the orchards.