Status of phosphorus, potassium and sulphur in the soils of Deh Karo Kho Kotri, district Dadu, Sindh

The macronutrient survey of soils of Deh Karo Kho Kotri district Dadu, Sindh was carried out during 2000-2001. One hundred soil samples were secured from 50 different sites at 0-15 and 15-30 cm depths. The soil samples were analyzed for available phosphorus, potassium and sulphur along with some physicochemical properties. 76% of soil samples (76%) were heavy (clayey to silty clay loam) in texture and the 24% were loams of various kinds (sandy clay to sandy loam). The electrical conductivity (1:2 soil: water) of the soil samples ranged from 0.24 to 4.46 dS/m at 0-15 cm and 0.24 to 2.69 dS/m at 15-30 cm with an over all average 0.67 dS/m at both depths. Thus, salinity was not a major problem of the soils of surveyed area (92% non-saline and 8% v.s. saline). 3. All the soil samples had pH value less than 6.0 at both depths (0-15 and 15-30 cm). Thus, sodicity was not a problem of the soil of area. Mostly soils were very slightly alkaline (54%) to medium alkaline (46%). Soil was low in organic matter, it declined, with depths and it ranged between 0.02 to 1.46 on an over all average basis value for both depths was 0.779. The over all average lime contents for both depths was 15.3%. Hence soils were highly calcareous in nature. AB-DTPA-extractable P of soil ranged from 0.20 to 13.7 mg P/kg in surface soil (0-15 cm) and 0.14 to 9.5 mg P/kg in sub-soil (15-30 cm). The over all average for both the depths was 3.42 mg P/kg. Mostly survey soils were low (52%) to medium (48%) in AB-DTPA content. AB-DTPA- extractable K of the surveyed soils ranged from 0.35 to 1.41 me K/100 g in surface soil (0-15 cm) and 0.28 to 0.97 me K/100g in sub-soil (15-30 cm). The over all average for both the depths was 0.63% me K/100g. Thus surveyed area was high in K. 0.001M CaCl2, extractable SO4-S of the soil ranged from 05 to 731 mg S/kg at 0-15 cm depths and 07 to 782 mg S/kg at 15-30 cm depths. On an over all average basis SO4-S was 210.01 kg S/kg soil. Therefore, surveyed. was high to very high in SO4-S. It is concluded that surveyed soils are mostly deficient in P but adequate in K and S. Hence, there no alarming situations so for SO4-S is concerned.