Development of Soil Moisture Content Monitoring System for Precision Measurement of Soil Moisture in Sub-Optimal Land for Palm Oil PlantationA P Nugroho, N B Kusumawati, Murtiningrum, A Wiratmoko, I M Haryadi, F A Pradana, Suwardi, Sukarman, S Primananda and L SutiarsoBIO Web Conf., 69 (2023) 05003DOI: https://doi.org/10.1051/bioconf/20236905003