Water-Use Production Functions of Selected Agronomic Crops in North-western New Mexico, Phase I

Efficient irrigation requires a knowledge of the consumptive use requirement of the crop plant. In northwestern New Mexico consumptive use of water, as influenced by level of nitrogen fertilization, of spring barley, pinto beans, and field corn was investigated for the 1980 growing season. Potential evapotranspiration was calculated using several methods, and crop coefficients developed. Crop yield has been demonstrated to be significantly and highly correlated to seasonal evapotranspiration. Crop coefficients greater than unity were routinely achieved at the higher yield levels during periods of peak evapotranspiration. As the level of nitrogen fertility increased from 10 to 200 kilograms per hectare the maturation period of the crop is lengthened and its rate of growth increased. The level of nitrogen fertility however does not appear to affect the water use efficiency of the developing crop. Both linear and curvilinear water production functions were produced with the form of the function varying upon the crop. Further research will allow a refining of the investigative technique and replication of the experimental methods in different seasons.

Project Numbers: C-90229, 1423660, 1423653, 1345682