by Momon Sodik Imanudin/Doctorate student in Department of Agriculture Postgraduate Programme in Sriwijaya University Indonesia on The International Seminar On Wetlands And Sustainability Kota Kinabalu, Sabah, Malaysia
The aim of this research is to develop the strategic operation for water management in the tidal lowland agriculture. Computer model DRAINMOD was able to use as a tool to evaluate the water status in the tertiary block. Computer simulation DRAINMOD has showed good performance that is indicated by the water table fluctuation in the simulation has the same pattern with the observed value. Statistic analysis was showed that the value of Mean of Absolute Errors is 0,084, Root Mean Square Error (RMSE) is 2,75 cm, model efficiencies 1,097 and Goodness of fit r2 is 0,92. Therefore the DRAINMOD model was accepted for simulation water table under shallow water soil conditions, and it was able to use to develop water management scenarios. The evaluation result showed that the possible water management scenarios in the area studies are rice-fallow; rice-corn, corn-corn, and rice-conservations. Operational water management in the field consists of water retention, control drainage, and maximum drainage. By using DRAINMOD model the Monthly operations for seasonal water management can be developed.
Key word: Tidal lowland, water management, DRAINMOD