Study on numerical simulation of soil moisture dynamic variation for walnut orchard under drip irrigation
View Fulltext  View/Add Comment  Download reader
  
DOI:10.7606/j.issn.1000-7601.2016.06.17
Key Words: walnut  drip irrigation  root system  soil water content  HYDRUS-2D
Author NameAffiliation
LI Dan College of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi, 830052, China 
ZHAO Jing-hua College of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi, 830052, China 
FU Qiu-ping College of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi, 830052, China 
HONG Ming College of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi, 830052, China 
MA Ying-jie College of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi, 830052, China 
Hits: 1241
Download times: 957
Abstract:
      Eight-year-old walnut trees were used to study the effect of root system on soil water content in different soil layers under drip irrigation. The root system was sampled from different soil layers. HYDRUS-2D model was built with consideration of water uptake by root system and checked. The results are described as follows: in vertical 2D profile, the soil layer of 40~60 cm being 0~30 cm away from the tree had the maximal fine root density of 1 618.216 m·m-3. The RMSE value and ME of the measured and simulated values from HYDRUS-2D are less than 0.0186 cm3·cm-3 and 0.0108 cm3·cm-3, respectively, suggesting that HYDRUS model could be used in the actual experiment research. The simulated results were different according to whether the effect of root system was considered, and the volumetric water content with root system considered is significantly lower. According to the simulated value for early stage of walnut, the soil content decreased a lot 6 days and 7days after irrigation, indicating that the irrigation cycle in earlier growing stage could be set 6 days or 7 days.