Effects of Desurfacing of Soils in South Eastern Nigeria

The effects of soil desurfacing on maize (Zen mays L) seed yield, plant height, leaf area index (LAI) were investigated in two locations (location I and location II) in South Eastern Nigeria. The soil loss depths were 0 cm (control), 3 cm and 6. cm. There were very significant correlations at P = 0.01 (r = 0.94, 0.96 and 0.94) between soil loss depths and leaf area index, (LAI), plant height and seed yield and P = 0.01 (r = 0.95, 0.94 and 0.94) between soil removal and LAI, plant height and seed yield in location I and location 11, respectively, during the study periods. These significant reductions in these crop parameters due to Surface sod loss were because of the reductions of the organic matter (2% and 18%) contents due to soil removal which affected these yield parameters. In comparison with 0 cm (control) at poultry site, yield reductions following 3 cm and 6 cm soil removal were 23%, and 55%, respectively. Corresponding yield reductions in locations 11 were 50% and 95%. There were also 6% and 29% reductions in plant height following 3 cm and 6 cm Surface soil loss, respectively, while at the location 11 there were 20%, and 85% reductions in plant heights due to 3 cm and 6 cm top soil removal. Leaf area index (LAI) was also reduced, for there were 43% and 62% reductions at location I and 42% and 94% in location 11 due to 3 cm and 6 cm top soil removal depths, respectively. The generally poor maize yield on eroded soils, even with NPK chemical fertilizer applications alone may not restore productivity on eroded areas.