Landuse impact on soil physical variability and erodibility in North Western subtropics of India

ABSTRACT

Aim: The study was conducted to determine the impact of landuse on soil physical properties and erodibility. Methodology: Representative soil samples were collected from surface and sub-surface soil depths. Soil physical properties and erodibility indices viz suspension percentage, dispersion ratio, clay/moisture equivalent ratio, erosion ratio, percolation ratio, clay ratio, erosion index and modified clay ratio were determined using standard procedures. Interrelationship among soil properties and erodibility indices were evaluated using Pearson correlation analysis (at 95% and 99% significance level). Results: Among landuse systems, the clay was highest in forest while least in soils under barren landuse. Lowest bulk density and highest value of maximum water holding capacity was found in forest soils. According to susceptibility to erosion, the landuse systems were found in the following order barren lands > cultivated systems (agriculture and horticulture) > forest lands. The ‘r’ values showed positive and highly significant correlations between sand content and bulk density with suspension percentage (SP), clay ratio (CR), modified clay ratio (MCR), dispersion ratio (DR), percolation ratio (PR), erosion ratio (ER), erosion index (EI) while negative and significant correlations of these erodibility indices were found with clay and porosity. Among the erodibility indices SP, DR, PR, ER and EI were positively and significantly correlated with each other. Interpretation: Physical quality of soil was higher in forest compared to other landuse systems. Erodibility of different landuse systems could be arranged in order barren lands > cultivated systems (agriculture and horticulture) > forests. The study was useful for suggesting remedial measures and landuse planning for future