Informatics Publishing Limited

Yi Li ¹, Yanling Shang ²

Affiliations
1 College of Water Resources and Architecture Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, CN
2 Guanyinge Reservoir Management Bureau, Liaoning, 117100, CN

Abstract

Treated wastewater irrigation (TWWI) is necessary under the background of a worldwide water crisis. To investigate wetting patterns and distributions of water droplet penetration time (WDPT), soil water content (θ), soil organic matter (SOM) and salt content (S) after tap water irrigation (TWI) and TWWI, single-pointsource trickle irrigation experiments were conducted on sandy and loam soils at three flow rates of 0.6, 1.0 and 2.7 mL·min^-1. For sand, infiltration was generally regular, WDPT increased small with maximal value of 1.4 s, and the ratio of wetting fronts (R_w) decreased to 1.1 with time. For loam soil, infiltration was not as regular as sand, R_w decreased with time, but larger than 1.5, WDPT increased significantly after TWWI, with maximal increment of 34.2 s at 1.0 mL·min^-1, and the distributions of SOM and S were irregular especially at flow rates of 2.7 mL·min^-1. SOM was not the main cause of the increment of WDPT for both soil types. Values of θ and S were considered to have contributed to the increment of WDPT for saline-alkali loam soil after TWI and TWWI. Particle content, especially sand content also affected WDPT. WDPT interacted with soil properties during TWW and TWWI.

Keywords

Point Source Trickle Irrigation, Soil Water Repellency, Soil Water Distribution, Soil Salt Distribution, Contour Map.

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