Physical andChemical Properties of Basaltic Soils Replanted with Coffee inGia Lai Province

Coffee isone of the main crops cultivatedon basaltic soils in Gia Lai province. However, the development of coffee is facing with various problems, for example the age of coffee trees, soils degradation, etc.Analyses of physical and chemical properties of basaltic soils undercoffee replantation showed that the soils have high clay content in deeper layers. At the first (0-20cm) and second layer (21-50cm) of the soil the average bulk density value ​​was0.84 g/cm3and 0.89 g/cm3, respectively. The density characteristic was in the range of 2,19-2,69 at the first examined layer and keeps constant value into deeper horizons. The total porosity was66.53% and 64.55% in the first and second horizon of the soil, respectively.The pH valuewas around 4.3 to 5.54. The organic matter content and total nitrogen achieved moderate to highvalues. Total phosphorus and available phosphorus contents showedhigh levelin the first horizonbutlow levels (poor) in the second layer. The total potassium and available potassium were low. The concentrations of Ca++, Mg++exchange were relatively poor. At the pHKClvalues between 4.69- ≥ 4.72 in the both horizons, the mobile aluminum concentration was notfound in the examined soils layers.