ZHAO Wei-xia 1, LI Jiu-sheng 1, CAI Huan-jie 2

1. State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100048, China
2. Key Laboratory of Agricultural Soil & Water Engineering of Northwest A&F University, Yangling 712100, China

Abstract: Application efficiency is an important consideration for selecting a suitable irrigation method in arid and semi-arid regions. A new concept of sprinkler efficiency considering the effects of microclimate modification was proposed in this article based on the energy and water balance model (CUPID model) describing the soil-plant-atmosphere continuum. The calculation duration of this model was defined, and its relative error was also evaluated. The results indicate that the regulation period of air temperature and humidity caused by sprinkler evaporation is related to irrigation time, and the calculation duration of sprinkler efficiency should be determined based on the time when both air temperature and humidity equal the values in the non-irrigated field. The relative error of sprinkler efficiency is about 6.0% when compared it with the value calculated by a Bowen ratio energy balance approach. The model could be used as an efficient tool to estimate the sprinkler efficiency.

Key words: sprinkler irrigation, field microclimate, irrigation efficiency, model

Published in: Journal of Hydraulic Engineering, Vol. 43, No. 11, 2012