In Situ Measurement of Stemflow, Throughfall and Canopy Interception of Sprinkler Irrigation Water in a Wheat Field

The sprinkler irrigation method has been widely used in agricultural fields due to its high water productivity and microclimate regulation traits. Quantitative analysis of the water distribution of sprinkler irrigation water by considering canopy influence is critical to evaluate crop growth and water use efficiency. In this study, stemflow was measured by collecting the water flowing down along stems using a high-adsorption sheet, throughfall water was measured by contains placed between wheat rows, and canopy interception was measured by the mass difference of plants between before and after sprinkler irrigation during wheat anthesis and grain-filling stages in the North China Plain. The results showed that the canopy interception water was between 0.6 and 1.3 mm, with a mean of 0.9 mm per sprinkler irrigation event for a leaf area index of approximately 4. Stemflow water was linearly related to the irrigation water and approximately 30% of the irrigation water. The throughfall water was also linearly related to the irrigation water above the canopy and accounted for approximately 60% of the irrigation water. The three components of sprinkler water are weakly influenced by the plant leaf area index, wind conditions and sprinkler irrigation system layouts in this study