基于EPIC模型的四川丘陵区黑麦草生长过程及其土壤水分动态变化模拟

发布时间：2018-07-16 22:02

【摘要】：明确黑麦草田土壤水分变化规律,对提高四川丘陵区人工草地管理水平具有重要的现实意义;校验EPIC模型,有利于改进并提高模型对黑麦草的模拟精度,对推进作物生产系统模拟与决策技术在草粮轮作系统的应用具有重要的实践意义。本研究通过田间试验与计算机模型相结合的方法,研究了四川丘陵区黑麦草生长过程及其土壤水分动态变化规律,明确了EPIC模型对黑麦草生长过程及土壤水分变化规律的模拟精度。结果表明,1)四川丘陵区黑麦草田土壤有效含水量在3-5月较低,深层(0.4~0.6m)土壤水分在5-10月间可以得到较好恢复,适当增加氮肥投入,可以显著提高黑麦草最大叶面积系数和饲草产量,在刈割4茬的条件下,氮肥施入量不宜低于75kg/hm2,且不高于225kg/hm2;2)黑麦草田0~1m土层土壤有效含水量模拟值和观测值间的r值为0.86~0.95,RRMSE值为6.0%~17.2%,土壤水分剖面分布动态变化的模拟值和观测值间的r值介于0.57与0.92之间,且大部分大于0.85;3)EPIC模型模拟的黑麦草叶面积系数和株高与观测值间的r值均大于0.90,在统计范围内模拟值和观测值间差异不显著;黑麦草产量模拟值和观测值间的r值大于0.90,ME值和R2间差异小于0.02。总体而言,EPIC模型能够较好地模拟黑麦草生长过程,对黑麦草田土壤水分动态变化规律模拟较为准确,可以用来评价四川丘陵区以黑麦草为主的草粮轮作系统对当地气候条件的适应性。
[Abstract]:It is very important for improving the management level of artificial grassland in hilly area of Sichuan province to make clear the law of soil moisture change in ryegrass field, and to check epic model, which is helpful to improve and improve the simulation precision of ryegrass. It is of great practical significance to promote the application of crop production system simulation and decision technology in grass grain rotation system. The growth process of ryegrass and the dynamic change of soil moisture in hilly region of Sichuan Province were studied by combining field experiment with computer model. The accuracy of epic model in simulating ryegrass growth process and soil moisture change was determined. The results showed that: 1) the soil available water content of ryegrass field in Sichuan hilly area was lower in 3-5 months, and the soil moisture in deep layer (0.4 ~ 0.6m) could be recovered better in May to October, and the input of nitrogen fertilizer should be increased appropriately. The maximum leaf area coefficient and forage yield of ryegrass could be increased significantly. The N fertilizer application amount should not be lower than 75kg / hm ~ (2) and not more than 225 kg / hm ~ (2) the r value between the simulated and observed values of soil available water content in 01m soil layer of ryegrass field is 0.860.95% RMSE value is 6.0 ~ 17.20.The simulated value of soil water profile distribution dynamic change and the r value between observation value and soil moisture profile distribution dynamic change are between 0.57 and 0.92. Most of the ryegrass leaf area coefficients and the r values between plant height and observed values simulated by epic model were greater than 0.90, but there was no significant difference between the simulated values and observed values in statistical range. R value of ryegrass yield between simulated and observed values is greater than 0.90 and the difference between R ~ 2 and R _ 2 is less than 0.02. In general, the epic model can simulate the growth process of ryegrass, and simulate the dynamic change of soil water in ryegrass field accurately. It can be used to evaluate the adaptability of ryegrass rotation system to local climatic conditions in Sichuan hilly area.
【作者单位】：西南科技大学生命科学与工程学院;西南科技大学成人与网络教育学院;
【基金】：粮食丰产增效科技创新项目(2016YFD0300210) 四川省教育厅项目(13ZB0299)资助
【分类号】：S152.7;S543.6

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