ABSTRACT
Tidal inundation type and soil chemical properties determine rice productivity in tropical acid sulfate swamp ecosystems

Nukhak Nufita Sari1, Masganti Masganti2*, Andin Muhammad Abduh3, Muhammad Rizky Romadhon3, Rachmiwati Yusuf4, Yanti Rina5, Eni Maftu'ah2, Khairil Anwar2, Puspita Harum Maharani2, Anna Hairani2, Muhammad Alwi2, Parlin Holomoan Sinaga2, Nurhayati Nurhayati4, Nurmili Yuliani4, and Olvie Grietjie Tandi4
 
Ensuring sustainable rice (Oryza sativa L.) production in tidal swamp ecosystems is critical for strengthening food security in Indonesia. Soil chemical properties, tidal inundation type, and planting season strongly influence rice productivity in these systems. This study evaluated soil chemical characteristics and rice productivity across tidal swamp areas in Tanah Bumbu Regency, South Kalimantan, Indonesia, by inundation type and cropping season. Field surveys, soil analyses, and farmer interviews were conducted in five villages. Selimuran and Mudalang were classified as Type B tidal swamps. In contrast, Rantau Panjang, Api-api, and Segumbang were categorized as Type C. Type B soils were acidic, while Type C soils were very acidic. Although both types exhibited low organic C, total N, and exchangeable P, Type B soils had higher P and base cation availability and lower concentrations of exchangeable Al, Fe, sulfate, and pyrite. The pyritic layer was shallower in Type C soils, increasing oxidation risk. Rice productivity was significantly higher in Type B systems (5.43 t ha-¹) than in Type C systems (3.76 t ha-¹). Seasonal responses differed between tidal types. Yields in Type B fields declined by 0.95 t ha-¹ from the dry to the rainy season, whereas yields in Type C fields increased by 0.45 t ha-¹. These findings highlight the importance of site- and season-specific nutrient and water management to enhance productivity and sustainability in acid sulfate tidal swamp ecosystems.
Key words: Acid sulfate soils, Oryza sativa, rice yield variability, seasonal water dynamics, soil chemical properties, tidal inundation, tidal swamp ecosystem.
1Lambung Mangkurat University, Faculty of Agriculture, Department of Agroecotechnology, Banjarbaru 70714, South Kalimantan, Indonesia.
2National Research and Innovation Agency (BRIN), Research Center for Food Crops, Cibinong, Bogor 16911, West Java, Indonesia.
3Lambung Mangkurat University, Faculty of Agriculture, Department of Soil Science, Banjarbaru 70714, South Kalimantan, Indonesia.
4National Research and Innovation Agency (BRIN), Research Center for Horticultural and Estate, Crops, Food and Agricultural Research Organization, Cibinong, Bogor 16911, West Java, Indonesia.
5National Research and Innovation Agency (BRIN), Research Center for Behavioral and Circular Economics, Jakarta 12710, Indonesia.
*Corresponding author (masg001@brin.go.id)
Received: 9 April 2026; Accepted: 14 July 2026, Available online: 7 September 2026.