Effects of land use on soil properties

An experiment was conducted with soils from five land use type namely: non cultivated soil, non treated (control), NPKSZn and NPKFYM treated rice growing soil and horticultural farm soil to observe the effect of land use on soil properties. Soil samples were collected from four depths vice: 0-10, 10-20, 20-30 and 30-60 cm of each land use. Soil pH, texture, organic matter, total nitrogen, available P, K and soil colour were determined. Particle-size distribution showed that most of the soils were medium textured with silt loam textural classes. Soil pH ranged between 6.22 – 6.64. pH of the surface soil was lower and increased with the increased of soil depth. Organic matter of all soils ranged from 0.21-1.70% where most of the soils were low to medium in level. There was a clear stratification of soil organic matter and it decreases with increased of depth. The highest soil organic matter was determine in NPKSZn fertilized cultivated soil followed by non cultivated soil NPKFYM applied soil, control plot of paddy soil and the lowest in horticultural farm soil. Total nitrogen followed the similar trend. Total nitrogen was varied from 0.020-0.109% where most of the soils were very low to medium in level. The available Phosphorus (P) was varied from 0.45-24.48 mg kg-1, where most of the soils were very low to optimum in level. The exchangeable potassium (K) was varied from 28.20-167.20 mg kg-1 where most of the soils were low to optimum in level. Cultivated rice growing surface soil had a lower K content than the sub-surface soil. The highest K content was observed in non cultivated soil. Wetland cultivation changes the soil color from dark grey to very dark gray. But dry land cropping turned the colour to reddish brown.