太行山前平原井灌农田点尺度土壤水分动态随机模拟  

Stochastic Model of Irrigated Farmland Soil Moisture Dynamics at a Point in Piedmont of Mount Taihang

作　　者：任庆福[1,2] 严登华[2] 穆文彬[2,3] 裴宏伟[4] 

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]中国水利水电科学研究院流域水循环模拟与调控国家重点实验室,北京100038 [3]河海大学水文水资源学院,南京210098 [4]中国科学院遗传与发育生物学研究所农业资源研究中心,石家庄050022

出　　处：《农业机械学报》2015年第3期131-141,157,共12页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家重点基础研究发展计划(973计划)资助项目(2010CB951102);'十二五'国家科技支撑计划资助项目(2012BAC19B03)

摘　　要：基于中国科学院栾城农业生态系统试验站2002—2008年夏玉米生长期内的土壤水分观测数据及2000—2008年的降水(灌溉)、气象、生物数据,结合Laio土壤水分动态随机模型研究了太行山山前平原典型农田点尺度土壤水分动态的随机性。结果表明:研究区2000—2008年夏玉米生长期内日平均降水量为10.71 mm,降水频率0.290 9,其中小雨、暴雨的发生频率表现出明显上升趋势,中雨的发生频率呈显著下降趋势,大雨发生频率表现出微弱下降倾向;玉米生长期的土壤含水率6月份处于增长期,7月份达到生长期最高值并稳定在32.2%的水平,8月份以后下降并在9月份趋于稳定;Laio模型模拟得到土壤相对湿度的概率密度函数在曲线形状(峰值、峰值出现的位置、90%置信区间)与数字特征(中位数、均值、方差)方面与观测结果一致(α=0.05),模型在井灌区具有很好的适用性,且可以将灌溉作为一次降雨事件来处理;应用Laio模型得到在多年平均降雨条件下,32.1 mm的田间净灌溉量可以在50%水平上使夏玉米生长期内的土壤含水率保持在田间持水量的80%以上。Un-deterministic dynamic of the energy process, water recycling and biological process in farmland is leading from its stochastic components, such as precipitation, evapotranspiration, heterogeneity of soil, topography and so on. The soil water balance is often described as a reservoir that is deterministically depleted via water losses due to evapotranspiration, runoff, leakage, and stochastically receives water from precipitation, so the stochastic property is the inherent nature of soil moisture. Based on the data of soil moisture, precipitation, meteorology and crop from 2000 to 2008 in Luancheng experimental station of agro-ecosystem of CAS on the stage of summer maize growth, the simulation was carried out with the stochastic model for soil moisture dynamics of the farmland at a point in piedmont plain of Taihang Mountain by using Laio model. The results show that the frequency and mean amount of daily rainfall from 2000 to 2008 in study area on the stage of summer maize growth are 0. 290 9, 10. 71 ram,respectively. And different changing trends were found among the frequency occurrence of different rainfall levels, the light rain and storm showed sharply increase trends, and the opposite trends was found in the moderate rain, for the heavy rain, the trends was slightly decrease. The revolution of soil water content of the growth stage of summer maize was expressed as increasing in June, stable in July, and decreased from August to September, and the maximum of soil water content was found in JuRy, the value was 32.2%. A good agreement between the result of modeling and observation was found based on the curve shape of probability density function which included the curve peak value, the position of the peak, the confidence interval of 90% and the digital characteristic of the relative soil moisture which included the median value, expected value, and the variance （a = 0.05）. And the Laio model had a good application in the irrigated farmland, and the irrigation was treated as a rain. The amount of the

关 键 词：井灌区 土壤水分随机性 点尺度 Laio土壤水分动态随机模型 

分 类 号：S152.7[农业科学—土壤学]