Shi Y.,North China University of Water Conservancy and Electric Power |
Shi Y.,Chinese Academy of Agricultural Sciences |
Qi X.,Chinese Academy of Agricultural Sciences |
Qi X.,Agriculture Water and Soil Environmental Field Science Research Station of Xinxiang City Henan province of CAAS |
And 10 more authors.
International Journal of Simulation: Systems, Science and Technology | Year: 2016
Partial root-zone drying irrigation (PRD) has been established as an efficient technology to save water without sacrificing crop yield, but its effectiveness in saving nutrients and reducing the impact on soil and water environment is less well understood. In this paper, we present the results of a field experimental study with potatoes to demonstrate that PRD can save not only water but also nitrogen. It keeps soil water at 90% of the field capacity, alternately keeping half of the roots dry in both subsurface-drip and furrow PRD. The measurements of soil nitrogen after harvest revealed that the residual mineral nitrogen in the soil from 0 to 30cm deep reduced by 29.72% and 17.05% respectively under drip PRD and furrow PRD compared to the corresponding full irrigation. Similarly, for soil in depth from 30 to 60cm, these increases to 13.52% and 33.17% respectively under drip full irrigation and furrow full irrigation compared to the corresponding PRD irrigation. It indicates a significant decrease in nitrogen leaching when irrigated using drip PRD. © 2016, UK Simulation Society. All rights reserved.
Li P.,Farmland Irrigation Research Institute of CAAS |
Li P.,Xi'an University of Technology |
Qi X.,Farmland Irrigation Research Institute of CAAS |
Qi X.,Agriculture Water and Soil Environmental Field Science Research Station of Xinxiang City Henan Province of CAAS |
And 4 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015
The suitable ratio of canal to well in the combined well-canal irrigation area can contribute to safety of groundwater environment and sustainable regional agriculture production. In order to investigate the influence of canal-to-well ratio on regional soil salinity accumulation, dynamics of groundwater depth, and groundwater hydrochemical characteristics in combined well-canal irrigation area, this study was carried out in a typical area in the People's Victory Canal area in China. The agriculture water consumption and precipitation in the People's Victory Canal area from 1954 to 2014 were collected, and the canal-to-well ratio, dynamics of groundwater depth and hydrochemical characteristics of groundwater from 2008 to 2014 in the research area were analyzed. The relationships between precipitation, groundwater depth, groundwater hydrochemical characteristics and the canal-to-well ratio were explored. The results indicated that there was a significant positive correlation between canal-to-well ratio and annual precipitation in research area (P<0.05). The variation coefficient of groundwater depth in the upstream of branch canals was higher than that of downstream of branch canals. Accumulated variation in soil electrical conductivity at 0-100 cm depth of 2nd branch canal was less than that of 1st branch canal and 3rd branch canal by 4.77% and 5.55%, respectively. Compared with the year of 2013, the area of groundwater depth greater than 11 m in 1st branch canal, 2nd branch canal and 3rd branch canal during the wintering period of winter wheat in 2014 was increased by 31.78%, 25.07% and 40.81%, respectively. When the water consumption amount and method were same, the high canal-to-well ratio can result in a small increase of area with groundwater depth beyond 11 m, indicating that the high canal-to-well ratio can alleviate the deterioration of groundwater depth. Alkaline trend of groundwater during dry and normal seasons in the research area was obvious owing to unrestrained groundwater exploitation. Affected by climate change, the reduction of precipitation in the combined well-canal irrigation area was obvious. Meanwhile, average irrigation amount by canal in the past 5 years was 2.90×108 cm3, accounting for 75.52% of mean annual irrigation amount. On the other hand, ground water overdraft in the research area would be remained in order to ensure agricultural sustainable production, which would be bound to aggravate alkaline trend of groundwater and expand the range of deep groundwater zone. It could be concluded that the suitable ratio of canal to wells decreased the groundwater exploitation and alleviated the alkaline trend of groundwater environment, moreover, maintained the reasonable groundwater depth. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.