Nguyễn Mỹ Hoa
Từ khoá: kali, đất, Đồng bằng sông Cửu Long
K fractions and soil K supply extracted by resin capsule in major soil groups in the Mekong delta, Vietnam
Investigating K fraction in 27 soil samples. Average total, non-exchangeable and exchangeable K were highest in saline intruded soils (474, 17.7 and 8.3 mmol/kg), lower in alluvial soils (449, 7.4 and 3.2 mmol/kg), in acid sulphate soils (326, 4.3 and 2.7 mmol/kg), in MocH Oa old alluvial soil (199, 3.7 and 1.6 mmol/kg) and lowest in sandy soils (162, 3.2 and 1.0 mmol/kg). Resin K at 1 day and at 14 days were at low to medium range. Soil K management in alluvial soils should be concerned because K fractions were at medium levels and cropping is now being intensified. Resin K can be used to study soil K supply to plants because of its good correlation with nonexchangeable and exchangeable K.