Physical and chemical changes in aquaculture pond bottom soil resulting from sediment removal

The influence of sediment removal on physical and chemical characteristics of aquaculture pond bottom soil was investigated at the Auburn University Fisheries Research Unit, Auburn, AL, USA. Soil samples were taken from 12, 34-year-old ponds. Sediment had never been removed from six of the ponds, and sediment was removed from the other six ponds 2 months before sampling. Concentrations of particle density, dry bulk density, porosity, soil moisture, organic carbon, total nitrogen, dilute acid extractable phosphorus, total phosphorus, calcium, magnesium, potassium, sodium, zinc, and copper were different (P < 0.05) in bottom soil between ponds from which sediment had been removed and ponds with sediment remaining. Differences between the two treatments were not found (P > 0.05) for particle size fractions (sand, silt, and clay), pH, aluminum, iron, and manganese. Sediment removal changed bottom soil quality, and concentrations of some variables were different from those of the original pond bottom soil.