Agricultural Soil Environment

Content

Summary

1.0 Introduction

2.0 Soil environment in north-western Nigeria
2.1 Key soil types and environmental soil conditions
2.2 Key Crops growing and farming system
2.3 Environmental soil problems
2.3.1 Soil Erosion and causal Agents
2.3.2 Desertification

Conclusion remarks

Reference

Summary

It is believe that a better understanding of agricultural soil environment is a key to better soil quality and high crop yield. Understanding the soil problems would certainly leads to solutions on how to tackle them. However, this could not only serve as a part of soil management but also as a part of economic development. For instance, when mother is healthy and fertile, there is more expectation from her to provide healthy and quality produce but when there is deficiency in any of the elements (either macros or micros elements), her produce may also affected, hence increasing poverty and hunger. High quality and fertile soil always provide better condition for the growth and development of plants (right from seed germination up to the maturity stage). Example, deficiency in N, P, and K in soil might lead to several problems to growing plant in a particular soil environment. These problems may include poor germination, stunting, and defoliations of plants, late maturity and also susceptible to both pest and disease attack leading to poor yield of the crops. Therefore, understanding soil environment is a key to high yield of crop production in the northwest one of northern Nigeria.

1.0 Introduction

Soil environment is a significant component of earth surface nature and as such provides many benefits to mankind. These benefits include agriculture, housing, vegetation, water and inter-communication between one geographical region to another. In agriculture, one of the most important benefit that soil environment offer is make available of moisture and nutrients contents for the basic requirement of plant growth (Russell and Greacen, 1977; Zachar, 1982; Yost et al., 1987; Wild, 1993; Brady and Weil, 2004; Usman, 2013). However, for many years soils in the globe have been facing lots of problems starting from nutrient depletion, as a result of land degradation factors such as erosion by wind and water, desertification as a result of deforestation or other related factors, poor vegetation cover as a result of human impact on natural resources such as human induced activities of destroying forest. These types of problems have lead to grave damages to regional soil environment, agricultural land cover and food availability as a result of organic matter lost or deterioration of soil structural quality and textural quality as well. Therefore, the objective of this synopsis paper is to provide a short note reference on soil environment as existing information in the context of north-west zone of northern Nigeria.

2.0 Soil environment in north-western Nigeria

Northern Nigeria can be divided in to two important geographical zones namely: the north-east zone and north-west zones. These two zones are dominated predominantly by the Hausa-Fulani people, who depend on farming and cattle rearing. The Federal Ministry of Environment Nigeria (FMEN, 2002) has indicated that the north-west zone included Kebbi, Sokoto and Zamfara States. These States bordered by the republic of Niger and Chad (Aregheore, 2005). The north-west zone covers a wide range of land described as the dryland of Nigeria, which constitute the main source of fodder and grazing land for livestock (Gadzama, 1995; Usman, 2007).

The north-west zone of Nigeria has an undulating plain topography characterised by high sand particles, usually very low in organic matter (Aregheore, 2005). The surface soil of the dryland area in the region forms an undulating plain at a general elevation covering about 450 to 700 m, and more than half of the region is covered by the ferruginous tropic soils, which are highly weathered and markedly particles (Mortmore, 1989). A large proportion of the region is also characterised by sandy-fixed undulating topography. The sandy soil is usually low in organic matter, nitrogen and phosphorous and may degrade rapidly under conditions of intensive rainfall.

Soils in the north-west-zone are well drained, with low water-holding capacity but having a deep water table in most of fadama area (Usman, 2003). The fadama flood plains areas of the region can be described as having flat-floored valleys that are flooded in the wet season only, and recedes during the dry season and leaves a coating of alluvial soil well covered. These seasonally flooded areas are called “fadama” in Hausa (Iloeje, 2001). The fadama soils have stable textural soil condition, and this largely controls the shape and size of pore space in soil, as such governs the infiltration capacity and run-off (Datta, 1986). Two soil textures are important in this circumstance – the fine and coarse-texture. Fine-textured soils have mostly narrow capillary channels; while coarse-textured soils have large and wide non-capillary pores; thus, the finer the texture the greater is the percentage of run-off (Usman, 2013).

2.1 Key soil types and environmental soil conditions

The key soil type in the north-west zone of northern Nigeria can be physically classified according the agricultural site as Aridisols in dryland site and Vertisols in fadama site (USDA, 1975). The dryland Aridisols are characterised as slowly permeable and most of the water is lost by run-off (Fitzpatrick, 1980). They might also have been formed under aridity from wind stored desert sands that accumulated over long period of time when the Sahara desert encourage several kilometres south of its present limits (Adegbola, 1979). The fadama soils in contrast, hold more water within the very-tight textural pores and have low run-off. They might have formed under flood plain nature covered largely with alluvial textural particles.

In addition, the dryland soils in the north-west zone might be also qualified to ferruginous tropic soils (D’Hoore, 1964); these ferruginous tropic soils can be characterised by having high sandy textural particles covering large areas of land, very low water holding capacity and low organic matter, low nitrogen content, low available phosphorus, neutral or moderately acid in pH (Jones and Wild, 1975). Thus, their ability to hold nutrients for plant growth in this circumstance is also very week.

Physically, the vegetation is usually spare and the surface is bare for long period. In essence, this may have contributed a lot to soil degradation by wind erosion, causing soil fertility decline in the zone. However as a matter of fact, this is one of the contributing factors to great soil environmental problem under agricultural condition in the north-west zone of northern Nigeria; and also making greater support to land degradation, which is also a worldwide phenomenon.

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