Laboratory of Soils, Division of Soil Science and Plant Production, Department of Plant Resources, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University
Laboratory of Soils, Division of Soil Science and Plant Production, Department of Plant Resources, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University
Laboratory of Soils, Division of Soil Science and Plant Production, Department of Plant Resources, Faculty of Agriculture, Kyushu University
九州大学大学院農学研究院植物資源科学部門植物生産科学講座土壌学研究分野
Laboratory of Soils, Division of Soil Science and Plant Production, Department of Plant Resources, Faculty of Agriculture, Kyushu University
九州大学大学院農学研究院植物資源科学部門植物生産科学講座土壌学研究分野
We measured the soil pH on fourteen soil samples collected from greenhouses under intensive fertilizer application. All the soil samples contained carbonate, but the pH values measured by conventional method were too low in view of carbonate equilibrium. We examined the effect of the soil to water ratio, shaking time and standing time and found that the pH gradually increased as the standing time was prolonged. It reached a maximum after 192 to 264 h of standing and then decreased. The maximum pH values were fairly close to those that are calculated from the thermodynamic equation based on carbonate equilibrium.