Enviromental Hazards series: Menace of Erosion and its effects.
Erosion have plagued mankind for years. It is one of environmental hazards that affect and threatens human existence and sustainabilities. Many environmentalists are very much interested in this concept and constrast it from other terms and occurances like weathering etc.
The Concept of Erosion
Etymologically, "Erosion" as a french word was conceptualized in the year 1540 from a latin word known as "erosio" Which means to "gnaw away". Gnawing or wearing away forms the simplest way of explaining what erosion is.
Erosion is the wearing away of the topsoil or earth crust and moved to a new location. Its a gradually action that can be severe when left unchecked. In the soil profile, the topsoil form the main portion that contains humus and home of soil microbes which enrich the soil. What do you think will happen when this important portion of soil keep wearing away.
Although Erosion is a natural processes, arthropogenic activities over years have increase its rate. These arthropogenic activities include bush burning, lumbering, deforestations, constructions, intensive agriculture, climate change and urban sprawl.
The main difference between erosion and weathering is that there is an action of agent of denudation that will carry the sediment to a new location and the distances varies.
Forms of Erosion
There are three main form of erosion. They includes: Physical and mechanical erosion which the sediments are moved clastically while in the chemical erosion, the sediment which disolved mostly in water are moved via dissolution.
The degradation caused by erosional agents is very high. It contributes to over 80% of the badlands all over the world. It renders those area unfit and unproductive.
Agents of Erosion
There are two main agents of erosion. They are rainfall and winds. Rains have strong influence in the wet zones while wind are predominant factor in the arid regions mostly the deserts. Other agents of erosion include glacier, abrasion, sea waves and scour.
With the rainful as the agent of erosion, there are four types, sheet, splash, rill and gully erosion. Both sheet and splash are mild type of erosion where the top layer of the soil are weared off by the drops of rainfalls while rill and gully leave a permanent faultlines on the surface indicating the waterline.
EFFECTS OF THE EROSION
There are many bad effects of erosion. They includes;
1). Migration of humans and animals. If left unchecked, land surfaces are subjected constantly and rendered them unfertile and unfit too. It turns into badlands. In the badlands, people and wildlives moved out to a better place.
- unfertile soil affects the agricultural activities.
- it affects socio-economic activities.
- human settlement are threatened the existence. In Anambra State, Nigeria. The gully erosion is very extensive and dangerous to human in things.