Soil samples: A pit approximately 1.5 m deep was dug in a field with Cheringa acid sulfate soil in Bangladesh, depending on the ground water level during March, 1990. The soil profile was studied based on standard methods of USDA (Soil Survey Staff 1975). The bulk samples obtained from each horizon were stored under field-moist conditions just prior to laboratory analyses, when the sub-samples were air-dried and crushed to 2mm before analyses. Soil analysis. After treatment with 1 M CH3COONH4 (pH 5.0) and 300 g kg-1 H2O2, respectively, particle size distribution was determined by the pipette method (Day 1965). Soil moisture under field conditions was determined by oven drying over-night at 105ºC (Black 1965). Organic matter content was determined by wet combustion with K2Cr2O7 (Nelson and Sommers 1982). Pot experiment: A pot experiment was conducted in the greenhouse of the Department of Soil Science, University of Dhaka during March to July, 1990 to analyze the response or rice plants grown in an acid sulfate (0-15 cm: surface) soil to various amendments. The rice variety BR 3 was used as the test crop. The experiment consisted of 18 treatments and 3 replications for each treatment. The doses of lime (CaCO3), basic slag, and MnO2 were selected based on a pre-incubation study with 300 g of soil in 500 mL beakers. The experiment was set up in a completely randomized design. The experimental treatments were as follows: T0)=no amendment; T1=P45 (P2O5, 45mg kg-1 as triple superphosphate=TSP); T2=P60 (P2O5, 60 rug kg-1 as TSP); T3 = 1m, (lime: CaCO3 5.0 g kg-1); T4 = 1m2 (lime: CaCO3, 7.5 g kg-1): T5=B, (basic slag,a 7.5 g kg-I); T6=B2 (basic slag, 12.5 g kg-1); T7=Mn50 (MnO2, 50 mg kg-1); T8=Mn75 (MnO2, 75mg kg-1); T9)= 1m,Mn50 (lime, 5.0 g kg-1+MnO2, 50mg kg-1); T10= 1m2Mn50 (lime, 7,5 g kg-1+MnO2, 50 mg kg-1); T11 =P451m, (P2O5 45 mg kg-1+ lime, 5.0 g kg-1); T12 = P45 1m2 (P2O5 45 mg kg-1+ lime, 7.5 g kg-1); T13 = leaching (L): initial soil ECe value of 1.54 S m-1 decreased to 0.25 S m-1 within 2 d by leaching (8 times, 500+ 200X6+ 100 mL) of soil bed about 15 cm thick with tap water at the rate of 1.8 L kg-1 of soil; T14=L+1m); T15=L+1m2; T16=L+B1; T17=L+B2. Two hundred and fifty grams of dried coarse sand, which was previously treated with 1M HCI, tap and distilled water were added to the bottom of each of the plastic pots (size: 28 cm height/24 cm diameter) and 6 kg soil was placed in each pot. Soil solution analysis: After 90 d of submergence, the soil solutions (leachates) were collected through a tube fitted at the bottom of each pot by allowing them to flow by gravity to fill a 150 mL Erlenmeyer flask which had been previously flushed with nitrogen gas to minimize the effect of O2 with the samples. The soil solutions were then subjected to the determination of the pH, ECw; N content (micro-Kjeldahl, Jackson 1973), P content (spectrophotometry at 440 nm after development of a yellow color, Jackson 1973), SO42- content (spectrometry at 420 mm after development of turbidity with BaC12 and gum acacia, Jackson 1973). Plant analysis: Plant height, number of tillers per hill, and shoot dry matter weight were determined at 30 (early tillering stage, ETS: 20-40), 60 (maximum tillering stage, MTS: 41-70), 90 (panicle initiation stage, PIS: 71-100), and 130 d (maturity, MaL) after transplantation, At maturity, the plants were harvested at 1 cm above the soil surface. One plant per pot was collected at each sampling time and the shoot dry matter, grain weight, percentage or filled grains, and thousand grain weight of rice were determined. The level of significance of the different treatments was calculated by Duncan's New Multiple Ranges Test (DMRT).