Performance Assessment of Soil Moisture Sensors for Precision Irrigation Scheduling

Abstract

Efficient water management is critical where water scarcity limits crop productivity. In order to overcome this problem, soil moisture sensors have been used for precision irrigation scheduling; however very less studies have compared different sensor types and their impact in vegetable crops. The study was conducted at Water and Land Management Training and Research Institute (WALAMTARI), Hyderabad to evaluate the performance of Electrical Resistance and Capacitance basedsoil moisture sensors for precision irrigation scheduling in a bottle gourd crop. Sensors were installed at two soil depths (0-15 cm, 15-30cm) and readings were compared with gravimetric soil moisture measurements and performance metrics included Mean Square Error (MSE) and Root Mean Squared Error (RMSE) were calculated. Results indicated that capacitance sensors provided more consistent and responsive measurements across varying soil moisture levels, while ER sensors showed greater variability under field conditions. Capacitance sensors were installed in bottle guard field and yield matrices were recorded. From the results, it can be concluded that Capacitance-based soil moisture sensor based irrigation system improved yield by 21% and irrigation water use efficiency by 51% compared to existing manual irrigation practice. Thus, it is recommended for precision irrigation scheduling to improve water use efficiency and crop productivity.