山地梨枣树耗水特征及模型  

A model for water consumption by mountain jujube pear-like

作　　者：辛小桂[1,2] 吴普特[1,2] 汪有科[1,2] 蔺君[3] 

机构地区：[1]西北农林科技大学水利与建筑工程学院,杨凌712100 [2]中国科学院水利部水土保持研究所,杨凌712100 [3]西北农林科技大学资源与环境学院,杨凌712100

出　　处：《生态学报》2012年第23期7473-7482,共10页Acta Ecologica Sinica

基　　金：国家科技支撑计划项目(2011BAD29B04)

摘　　要：由于枣树树龄、品种、冠层形态、下垫面以及枣树种植区气象条件不同,导致榆林地区枣树耗水规律研究缺乏系统性。本文利用HYDRUS-1D数学模型对枣树耗水规律进行了研究。2008—2010年通过对榆林米脂县不同树龄山地梨枣树叶面积指数、根系分布规律,作物系数的研究,结合HYDRUS-1D模型预测所需土壤、气象等参数的测定,对山地梨枣树土壤水分动态进行了模拟,并对土壤水分模拟结果与实测值进行拟合,反推出模型计算所需的消光系数及土壤水分胁迫系数等参数。结果表明:HYDRUS-1D模型能够很好模拟该地区梨枣树土壤水分动态变化过程,该地区成年(8龄)梨枣树从发芽开始到梨枣收获期结束共耗水267 mm。The regulation of water consumption by mountain jujube trees, jujube pear-like, has not been previously researched in a systematic fashion because of differences among the jujube samples, including age, variety, canopy morphology, meteorological conditions, and land surface conditions. Numerical simulation is an effective and convenient method to investigate the patterns of water consumption of trees, including jujube trees. Therefore, this paper introduces a mathematical model （HYDRUS-1D） to simulate the soil moisture requirements for jujube pear-like. First, to develop the model, the forecast parameters of the HYDRUS-1D model, such as soil properties, weather conditions, leaf area index （LAI）, root distribution, and basal crop coefficient, were measured in the northern hilly area of Shannxi Province, China, from 2008 to 2010. Second, the dynamic characteristics of soil moisture in a rain-proof plot experiment were roughly simulated using the HYDRUS-1D model, then, we adjusted the model so that the simulated results better fit the measured data of soil moisture. We inversely extrapolated the parameters of soil water stress coefficient and extinction coefficient, which determine the values of the potential transpiration and potential evaporation, respectively, for the atmospheric boundary conditions. Finally, using the parameters we estimated, we used the HYDRUS-1D model to predict water consumption by eight-year-old jujube pear-like trees in the field. The results showed the following. （ 1 ） The changes in LAI of jujube pear-like were consistent with a Gaussian function from germination to fruit ripening. Average LAI of jujube pear-like increased from young to old trees, but the inter-annual differences in LAI decreased in trees that were older than six years. （2） Root depth of jujube pear-like increased linearlywith the age of the tree. At the same time, the distribution of capillary roots decreased linearly with an increase in the root depth. The percentage of capillary roots at a depth of 40

关 键 词：山地梨枣 作物系数 土壤水分胁迫系数 耗水规律 模型研究 

分 类 号：S665.1[农业科学—果树学]