Functional design of smart evaporative irrigation for mina-padi system in Indonesia

Abstract

The smart evaporative irrigation is offered as an appropriate option in regulating irrigation water more effective. Smart means the system of irrigation is automatically controlled by a floating ball valve based on evaporation and evapotranspiration rate without electrical power. The objective was to evaluate the functional design of the evaporative irrigation on water demand aspect particularly for Mina-padi (paddy–fish farming). The system was evaluated based on the experimental field in the lab-scale since 10 July 2020. There were three irrigation regimes, i.e., continuous flooded (CR), wet (WR), and dry (LR) regimes. During the vegetative growth stage, the smart evaporative irrigation worked well. The irrigation was supplied by a floating ball valve automatically according to the evapotranspiration rate. The actual water levels were well kept and fitted to the setpoint as indicated by low mean absolute error (MAE). The CR regime needs more irrigation water and evaporated more water through the evapotranspiration process. Its rate was highest ranged between 5.81 – 6.6 mm/day. On the other hand, the LR regime has the lowest evapotranspiration rate in between 1.65 – 4.09 mm/day. The irrigation control system became crucial for control the evapotranspiration rate in which less irrigation water evaporate less water.

A Model of Evapotranspirative Irrigation to Manage the Various Water Levels in the System of Rice Intensification (SRI) and Its Effect on Crop and Water Productivities

“…Under the absence of inundation, such as in the WSI regime, the rate of evapotranspiration is low [25]; consequently, the total actual evapotranspiration was lowest compared to the two other regimes (Table 3). Then, the average actual coefficient of this regime was also lowest.…”

“…At 10 DAT, the regimes produced the same number of tillers (Figure 9). A significant increase in the number of tillers occurred from the vegetative growth stage (25)(26)(27)(28)(29)(30). In this phase, the number of tillers was 11, 8, and 8 in the CFI, MFI, and WSI regimes, respectively.…”

“…Theoretically, an evapotranspirative irrigation system is elaborated from the concept of evaporative irrigation [24]. The functional design has been designed and developed [25], as well as tested for lettuce plants [26]. However, the system has not been tested with various irrigation regimes with different water levels under specific weather conditions for SRI paddy cultivation.…”

Effect of different feed nitrogen on nutrient flow, performance, and productivity in the minapadi system

“…Some farmers combine rice cultivation with fish farming to implement effective water use. This method is known as mina-padi [2]. This agriculture has been known for a long time and provides both carbohydrates and proteins.…”