Feasibility Study on Soil Water Retention in Irrigated Paddy Using Biocement

Soil salinity and low water-holding capacity are major limitations to sustainable rice cultivation in the northeastern region of Thailand. This study investigates the application of biocement, developed through Microbially Induced Calcite Precipitation (MICP), as means to increase water retention in irrigated paddy field with saline-sodic soils. Biocement was synthesized using halotolerant microbial strains Bacillus licheniformis and Sporosarcina pasteurii DSM33, isolated from fermented fish sauce and capable of calcite precipitation under saline conditions. The formation incorporated geopolymer binders using powder of igneous rock from gold mining tailing, enhancing the durability and reducing environmental impact. The implementation site was the Irrigation Water Management Experiment Station No. 3 (Huai Ban Yang), located in Nakhon Ratchasima Province, characterized by loam-texture saline-sodic soil, with moderate dispersion and capillary salt accumulation during dry season. Biocement slab with 0.75x0.75x0.085 m, was installed in lysimeter tank to simulate field conditions and access the effect on soil hydraulic behaviour. The objectives included reducing soil hydraulic conductivity and increasing the soil field capacity and available water content. Laboratory tests and field observations showed that the biocement treatment reduced vertical infiltration, improved soil cohesiveness, and significanty enhanced water retention during irrigation cycle. These findings confirm the feasibility of biocement as a sustainable solution for water retention in rice paddies affected by salinity. The results also support broader applicayions in bio-salination and regenerative agriculture, with implications for improving crop resilience, mitigating salt stress, and promoting carbon sequestration in semi-arid landscape.