Characteristic and model building of stemflow of corn plant in different growth stages

In order to systematically determine the stemflow at different growth stages of corn plants with different rainfall intensities and to establish simple, practical models, stemflow of corn (Zea mays L.) plants was determined in different growth stages under simulated rainfall conditions. The relationship between corn stemflow, corn leaf area, and rainfall intensity was analyzed, and a stemflow model for a single corn plant was developed. The results showed that when averaged across all grow stages, corn stemflow accounted for 44.55% of the total rainfall. Stemflow amount tended to increase as corn leaf area and rainfall intensity increased. In contrast, the stemflow ratio increased as leaf area increased, but did not change significantly as rainfall intensity increased. Data from this study were used to establish a theoretical model, a semi-empirical model, and an empirical model of stemflow for a single corn plant. The accuracy of all three models for estimating corn stemflow at different growth stages was verified to be within required limits. Among the three models, the semi-empirical model was the most simple and accurate in actual measurement and application. The stemflow models developed in this study are useful tools for studying the spatial variation of rainfall and sprinkler irrigation water beneath a corn canopy and its effect on soil water movement and soil erosion. The models can also provide theoretical guidance for water balance under irrigation and precise management of water and fertilizer application in corn cropping systems.