Soil degradation around Orji municipal solid waste dump site: a spatial assessment.

Abstract

The present study assessed the impact of municipal solid waste dump on the degradation of soil around Orji dump site. A total of 15 soil samples were collected for this study. Twelve soil samples were collected around the dump site at 0 m, 10 m, and 20 m distance and three from Imo State University (IMSU) research farm as control. The samples were collected from the east, west, north, and south of the dump site. The samples were subjected to laboratory analyses. The mean results obtained indicate that the values of the dump site soil parameters analyzed ranged from 86.67 to 89.00% (sand), 4.33 to 5.67% (silt), 7.00 to 7.67% (clay), 6.80 to 7.50 (pH), 4.33 to 7.00 dS m^-1 electric conductivity (EC), 0.0028 to 0.0045 mg kg^-1 (salinity), 2.36 to 3.76% soil organic matter (SOM), 24.13 to 38.93 cmolc kg^-1 cation exchange capacity (CEC), 4.50 to 9.57 cmolc kg^-1 calcium (Ca), and 1.0 to 2.25 cmolc kg^-1 magnesium (Mg). At the control, mean values were 81.24% (sand), 6.39% (silt), 12.45% (clay), 5.69 (pH), 0.47 dS m^-1 (EC), 0.0005 mg kg^-1 (salinity), 1.99% (SOM), 5.08 cmolc kg^-1 (CEC), 2.17 cmolc kg^-1 (Ca), and 1.67 cmolc kg^-1 (Mg). These values showed substantial enrichment. Correlations indicate that EC, salinity, and CEC majorly determined the availability of most of the parameters analyzed. Soil degradation index (SDI) was used to determine degradation around the dump site. It ranged from 2.546.61% (0 m) to 1573.50% (10 m) and 1.603.73% (20 m). Thus, distance affected the rate of soil degradation in all directions away from the dump site.