Water Use by Flooded Rice in Puerto Rico

Abstract

Evapotranspiration with flooded, well-established rice averaged 0.61 cm/day, with a range from 0.31 to 0.84 cm/day. These variations resulted largely from climatic changes since they were closely related to evaporation losses from an open pan. The equation Y = 0.2691 + 0.4696 X (r = 0.97**) describes the relationship between evapotranspiration with rice and open pan evaporation, which averaged 0.55 cm/day during the experiment. Percolation losses in Toa soil (Mollisol) averaged only 0.20 mm/day after the first 2 weeks of flooding.