ASSESSMENT OF SOIL DEGRADATION IN MAKURDI BENUE STATE
CHAPTER ONE
INTRODUCTION
- 1 Background of the Study
Soil is one of the world‘s greatest resource. It has been described as a natural body of animal, mineral and organic constituents, differentiated into horizons of variable depth which differ in morphology and physical, chemical and biological characteristics (Joffe, 1948). It is an important natural resource that either directly or indirectly supports most of the planet’s life. A major function of soil on man is that it supports food supply and food security. Soils affect food security directly because it supports agriculture. Agriculture produces the food we eat and provides the primary source of livelihood for 36% of the world‘s total workforce (ILO, 2007). Therefore, threat to soil is threat to food security and economies which rely on agriculture. Food security is directly linked to the ability of the land to support populations (Scherr and Yadav, 1996).
Global concern about soil degradation has grown because of its threat to agriculture and food security. Low agricultural production, food insecurity, low income of the rural population and poverty are consequences of soil degradation (Junge, Deji, Abaidoo, Chikoye and Stahr, 2008). Agcaoili, Perez and Rosegrant (1995) estimated that increasing degradation would lead to as much as 10% decline in productivity in the developing countries and could lead to worsening malnutrition in the developing world.
Some of the challenges posed by soil degradation to food security in the developing countries are; long-term investment and appropriate technology development, dampened economic growth effects of lower farm incomes in irrigated, high quality rain fed and densely populated marginal lands due to lost soil productivity and threat to nutrition and deaths from malnutrition and diseases associated with poor diets (Eswaran, Almaraz, Van den Berg and Reich, 1997; Swift and Shepherd, 2007).
Soil degradation is a loss of soil function. It is a serious and most common form of land degradation because the soil is the basis for production (Blum, 1998). It encompasses physical, chemical and biological deterioration. Examples of soil degradation are loss of organic matter, decline in soil fertility, decline in structural condition, erosion, adverse changes in salinity, acidity or alkalinity, and the effects of toxic chemicals, pollutants or excessive flooding. Soil degradation is the decline in soil quality caused by its improper use, usually for agricultural, pastoral, industrial or urban purposes. A soil is said to be degraded if the loss of basic qualities which manifest in reduced yields, is permanent (Mbagwu, 2003). Soil degradation occurs globally but its negative impacts are most felt in regions which depend solely on agriculture for its income (Swift and Shepherd, 2007). Increased pressure on land as a result of increasing world population has led to increased degradation of world soils. Soil degradation may be exacerbated by climate change.
