Soil degradation assessment of some selected land use in two Agro ecological zones of Gombe State, Nigeria

Abstract

Soil degradation remains a global environmental phenomenon caused by anthropogenic activities. The assessment of degradation status of soils in some selected land uses of two agro ecological zones of Gombe state was carried out. Representative soil samples from four land uses were collected from 0 - 30 cm depths (cultivated, Fadama, forest and mining land). The soil samples were labeled, air-dried, crushed, sieved through a 2 mm mesh, and subjected to various physical and chemical analyses. Data collected were subjected to descriptive statistics and soil degradation assessment was done following standard procedures. The levels of degradation of soils were assessed using the standard indicators and criteria for land degradation assessment by the Global Assessment of Land Degradation. Analytical data from each sample were placed in a degradation class by matching the soil characteristics with the land degradation indicators, while estimation of the overall degree of degradation was arrived at mathematically, using physical, chemical, and biological parameters. The results shows that the textural class of the soil ranged from clay to sandy loam. Permeability ranged from 0.10 to 7.97 cm hr-1 corresponding low to high permeability. Bulk density ranged from 1.24 to 1.62 g cm-3. Organic matter was very low in all the study sites. Available phosphorus ranged from 6.2 to 15.5 mgkg-1. Total nitrogen was predominantly low (0.05 – 0.08%) in all the land uses. Exchangeable Sodium Percentage (ESP) of the sites depicted that most of the soils were non sodic soils (0.71 – 1.61%). The potential for all the land uses are moderately degraded varied from Fadama land (41.67%), cultivated land (44.44%), mining land (47.22%) and forest land (50%), respectively. The major barriers in the study areas were low fertility, and soil conservation measures. In order to optimize crop production in these areas, there may be need to introduce soil conservation measures. The practice may include use of farm yard manure, compost, crop residues, green manure or poultry manure to boost soil fertility. Regular monitoring of the fertility status of the soils is encouraged.