Planting time optimization on tidal agricultural land

Abstract

Tidal agricultural land (TAL) is a marginal farming field that is highly available but yet to be optimized in Indonesia. Productivity enhancement of TAL is achievable through agriculture technologies, but water management is the key solution to TAL main problems, i.e. flood and drought cycle. The main objective of this research was to predict tidal cycle for available planting time optimization in TAL. Research was conducted on 100 hectares TAL in Jejangkit, Barito Kuala, South Kalimantan, with the Alalak river become the main subject of the hydrodynamics monitoring. Watershed water balance simulation model run on 10-day interval was utilized to predict the tidal cycle with 4 input parameters including water-level, precipitation, percolation, and evapotranspiration. The prediction result showed that the available planting months in Jejangkit TAL was about 8 months, between the first or second 10-day of May and third 10-day of January or first 10-day of February (calibration and validation R2 were 0.78 and 0.92, respectively). On-field validation in Jejangkit recorded flood event started during the third 10-day of January 2020, which indicated that the prediction was reliable. This result shows that tidal cycle could be simulated using watershed water balance model to assist farmers on TAL’s productivity enhancement.