Soil Mechanical Composition and Texture as Indices for On-site and Field Precise Choice of Land Use Type to Adopt

Abstract

The soils of Agoi-Ibami in central Cross River State of Nigeria were evaluated for their mechanical and textural compositions in the field. The objective was to present to small scale, subsistence farmers, with limited access to external farm-inputs for time consuming and expensive laboratory analysis, soil data for on-site and field land use and management decisions. Three profile pits were sunk, along three well defined and selected toposequences, on three landscape elements of crest, middleslope and valley bottom in three land use types of forest (FS), rubber (RS), and arable (AS). Relevant environmental properties were inventorized and the profiles described in the moist state. Their textures were determined by the feel method in the field among other morphological properties. The field investigation showed the soils to be predominatly loamy soils. After the field investigation, soil samples were collected from the morphogenetic horizons for determination of their mechanical composition in the laboratory to supplement the field investigation. Their loamy textures and mechanical composition inferred from their loamy texture impact unique physical and chemical properties like good water holding capacity, good drainage, fertile and productive soils and good for irrigation. Loamy soils exhibit properties intermediate between sandy and clayey soils. Loamy soils are considered best for agricultural production because they hold more water and nutrients than sandy soils and have better drainage, aeration and tillage properties than clayey soils. They have slight plastic and sticky workable properties ideal for crop growth and crop productivity. Therefore knowing the texture of soils and their mechanical composition in the field their properties can be inferred and land use and management decisions can be taken on-site without recourse to expensive and time consuming laboratory analyses which are beyond the capacity of resource poor small-scale and subsistence farmers in developing countries and or sub-Saharan Africa. The land use and management decisions are taken after mutual adaptation and adjustments of the description of the land use and the increasingly known soil qualities in the field.