南疆枣园能量闭合分析及腾发特征

Energy closure analysis and evapotranspiration characteristics of jujube orchard in southern Xinjiang

为验证涡度相关系统在干旱地区枣园测定腾发量的适用性及探究枣树腾发规律。本试验采用涡度相关法与水量平衡法对枣园的能量闭合度和腾发量进行测定。两种方法测定腾发量的相对偏差、纳什系数(NSE)与均方根误差(RMSE)分别为0. 041mm·d-1、0. 84与1. 09。以花期枣园为例,0. 5h时间步长的能量闭合度在60%-100%之间,花期能量闭合程度为79. 23%。充分灌溉下枣树全生育期腾发总量为560. 78mm,其中萌芽期与果实发育期腾发量占全生育期比重最小与最大,分别为6. 00%与48. 10%。

In order to verify the applicability of vorticity correlation system in determining the evapotranspiration of jujube orchard in arid areas,and to explore the law of evapotranspiration in jujube orchards,the energy balance and evapotranspiration of jujube orchard were measured by water balance method and eddy covariance method. The relative deviation,Nash coefficient( NSE) and Root mean square error( RMSE) of the evapotranspiration measured by the two methods were 0. 041mm·d-1,0. 84 and 1. 09. Taking the red jujube orchard in blossom season as an example,in the half hour step,the energy closure is between 60%-100% and the energy closure degree is79. 23%. Under full irrigation,the total evapotranspiration of the jujube orchard during the whole growth period is560. 78 mm,and the germination period and fruit development period accounted for the smallest and maximum proportion of the whole growth period,they are 6% and 48. 10%,respectively.