The characteristics of evapotranspiration and crop coefficients of an irrigated vineyard in arid Northwest China
The characteristics of evapotranspiration and crop coefficients of an irrigated vineyard in arid Northwest China
复制标题
西北干旱地区灌溉葡萄园蒸散量及作物系数特征
DOI：
10.1016/j.agwat.2018.09.023
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发表时间：
2019
影响因子：
6.7
通讯作者：
Shang Shasha
中科院分区：
文献类型：
--
作者：
Wang Shangtao;Zhu Gaofeng;Xia Dunsheng;Ma Jinzhu;Han Tuo;Ma Ting;Zhang Kun;Shang Shasha
绿洲效应可能对极端干旱条件下的灌区作物水分利用产生重要影响。作物系数及其影响因素的研究对于准确确定该条件下的灌溉制度至关重要。在灌溉葡萄园进行了为期两年的试验，估算了蒸散量(ET)及其蒸发量(E)和作物蒸腾量(T)两个分量，并制定了适宜的西北干旱地区中国作物系数(KC、KCB)。研究了“绿洲效应”对Kc的贡献，以及KandKcb与冠层导度(GC)和叶面积指数(LAI)的关系。利用田间资料和双K-卡普法计算了蒸散量和作物蒸腾量的局地Kc值。2014年和2015年的日ET值分别为0.8~9.87 mm d−1和0.99~8.73 mm d−1，对应的T/ET值分别约为58.4%和55.1%。在生长初期、中期和后期，当地平均Kcb值分别为0.79、1.31和1.08，而相应的Kcb值分别为0.17、0.97和0.64。干旱平流在两个研究期分别占日Kc值的16.9%~57.4%和1.4%~49.0%。KandKcbtoLai都是线性回归，而toGc1是指数回归。在用来预测KandKcb时，LAI是比Gcb更好的指标。这些结果将帮助种植者提高灌溉效率，并量化在这种条件下单个因素对KandKc的贡献。
Oasis effect may have significant impacts on the crop water use in irrigated fields of extremely arid conditions. Studies on crop coefficients and its relevant influence factors are essential to accurately determine the irrigation scheduling under such conditions. A two-year experiment was conducted in an irrigated vineyard to estimate evapotranspiration (ET) and its two components: evaporation (E) and crop transpiration (T), and to develop appropriate region-specific crop coefficients (Kc,Kcb) in arid Northwest China. The contributions of “oasis effect” toKc, the relationships of bothKcandKcbto canopy conductance (Gc) and leaf area index (LAI) were investigated. Local values ofKcfor evapotranspiration and crop transpiration (Kcb) were calculated using the field data and the dual-Kcapproach. The dailyETranged from 0.80 to 9.87 mm d−1and from 0.99 to 8.73 mm d−1in 2014 and 2015, respectively, with correspondingT/ETvalues amounting to approximately 58.4% and 55.1%. The locally averagedKcvalues were 0.79, 1.31, and 1.08 during the initial, middle, and late growth stages, respectively, versus correspondingKcbvalues of 0.17, 0.97, and 0.64. Arid advection accounted for 16.9 to 57.4% and from 1.4 to 49.0% of dailyKcduring the two study periods. BothKcandKcbtoLAIis a linear regression but toGcis an exponential one.LAIis a better indicator thanGcwhen it is used to predictKcandKcb. These results will help growers to improve irrigation efficiency and quantify the contributions of individual factors toKcandKcbin such conditions.