Experimental Study on Characters of Wetted Soil in Moistube Irrigation
ZHANG Dun, NIU Wen-Quan, ZHANG Lin-Lin, SHI Li-Yan
(1.Institute of Soil and Water Conservation, Chinese Academy of Sciences & Ministry of Water Resources, 712100, Yangling, Shaanxi； 2.Graduate University of Chinese Academy of Sciences，100049，Beijing；3.College of Water Resources and Architectural Engineering, Northwest Agriculture & Forestry University, 712100，Yangling, Shaanxi：China ）
Abstract：This study was conducted to investigate the soil water movement of line source infiltration under miostube-irrigation. Soil box experiments was used to study soil water distribution and analyze the effect of the soil texture and bulk density on the characteristic of wetted soil.The results showed that the wetted soil looked like cylindrical object which with pipe as it’s axle centre and clay loam soil was approximate with cylinder, the cross section of sandy soil as obpyriform shape. The ratio of R∶X∶H was 1∶0.90∶0.99 in clay loam soil and 1∶ 0.81∶0.95 in sandy soil, respectively. (R: horizontal migration distance; X: vertical upward distance; Y: vertical downward distance). The relationship between the horizontal or vertical moving distance of wetting front with irrigation time appeared as a power function. The effects of the soil texture and bulk density on the characteristic of wetted soil were significant in mois-tube irrigation. Miostube-irrigation has small flow, the unit length flow rate was not exceed 210mL·m-1·h-1, which could automatically adjust with the change of soil water content, cumulative infiltration has a linear relation with irrigation time. Water distribution in the volume of wetted soil was a concentric circle with the pipe. Most of soil water content lied between 80% and 90% of field capacity. Miostube-irrigation has high irrigation uniformity, which reached 95.62%. The effect of water saving of miostube-irrigation is prominent, which is suitable for crop water demand in the arid regions.
2012, Vol. 10 
