AVAILABILITY OF POTASSIUM IN SOILS OF OIL PALM PLANTATION INFESTED WITH DIFFERENT WEEDS, RONIKA PALM PLANTATION, EKASA VILLAGE, OVIA NORTH EAST LOCAL GOVERNMENT AREA, EDO STATE, NIGERIA.

ABSTRACTS

The study was carried out to investigate Nitrogen availability in soils of an oil palm plantation infested with different weed types in Ekasa Village, Ovia North East Local Govt area of Edo State, Nigeria. Soil samples were collected at two different depths (0-15cm and 15-30cm) with three replicates each, at four different weeds infested areas covering at least one acre each. The weeds investigated are: Spear grass (SR), Guinea grass (GR), white weed or goat weed (WR) and Chromolaena odorata (Siam weed) (CR). The results showed that the soil of the plantation is clayey sand which is moderately acidic.  The portions with GR and CR have high organic carbon content at 0-15cm but moderate organic carbon content at 15-30cm while the portions with WR and SR have moderate organic carbon contents at both depths. The potassium content in the GR portion is the highest (0.403Cmol/kg) followed by portion with WR 0.381Cmol/kg) at 0-15 cm depth while the portion with SR is the lowest (0.241/kg). The 15-30cm depths  also followed same trend. There are no significant differences among the mean value of potassium in the four portions. The results also showed that the portion with CR has the highest reserve of organic carbon and nutrients reserve followed by GR while WR has the lowest.