The natural environment is characterised by a wide range of complex forms and processes. These forms, which greatly influence the environment are various natural factors of climate, soils, vegetation, minerals, water, etc. The environment is also influenced by other human factors like population, economy, cultural practices, science and technology.
The environmental forms and processes are linked and interrelated in a complex manner, such that the nature of the environment varies from place to place and through time. The basic nature of the environment (i.e. its changes and variations) is determined by the behaviour of the natural systems of land, water, air and life which make up the interacting components of the environment that eventually maintain an environmental balance.
An environmental balance assumes that the factors or elements of the environmental balance do not change so as to maintain an equilibrium between the various components of the ecosystem. However, an equilibrium is hardly maintained in any environment for a long period. Changes are bound to occur as a result of intentional and, or unintentional interventions by man, animals and natural factors. The type of environmental change that may affect an area could be a short or long-term one resulting from some alterations in one or more of the factors that control the natural systems. As earlier said, the alterations in the environment may be caused by either natural or human interventions which may bring about unexpected changes in climate, vegetation, soil or drainage patterns and characteristics in the affected area.
Causes and Effects of Natural Intervention
Natural intervention may occur as a result of any of the following phenomena: global climatic change, vulcanism, tectonic movements, change in sea level, forest colonisation, desertification, etc. The changes triggered by the natural intervention may be quite significant where their occurrences have affected large areas of the earth’s surface.
Firstly, the effects of such interventions are to destabilise the scale of operation of environmental processes within the natural system.
Secondly, a new scale of interactions is then imposed that would bring about changes in the natural systems. Simply illustrated, an unexpected global change in atmospheric moisture content would impose severe changes on the precipitation regime on the earth’s surface. This will have serious impact on the nature of surface drainage and vegetation cover as well as soil patterns. When such an intervention occurs on a geological time scale, it could be an imposed, irreversible environmental change on the entire surface of the earth or some reasonable part of it.
Causes and Effects of Human Intervention
Human interventions have resulted from the increasing pressures of rising human population, activities and demand for the basic necessities of life which have been exerted on the environmental resources.
In the world today and over the years, human activities have become the dominant forces for the alteration of the natural environment as man attempts to improve on his living conditions. The impact of these alterations is more serious on the processes of the natural system. These activities of man have resulted in the modification of the climate, landforms, soils, vegetation and drainage systems in many parts of the world. In other cases, the detrimental effects of these human activities have created environmental hazards which have degraded the quality of the natural environment.
Human activities related to agriculture (bush burning, over cropping, grazing, irrigation, deforestation, etc.), mining, forest exploitation, water resources management, settlement expansion (urbanisation) and so on, have had some damaging effects on the environment. The problems of overpopulation, overgrazing, use of primitive or inappropriate technology, etc., have drastically modified the environment. The affected areas have been so altered that little or no aspects of its original conditions of the natural environment are left behind.
Other effects of uncontrolled human intervention include environmental hazards like soil and coastal erosion, flooding, deforestation, land subsidence, as well as pollution. From the above, it is clear that human activities have a negative impact on the natural environment. Therefore, the mode of human intervention of the environment should be controlled and properly planned.
However, aspects of human intervention that enhance the quality of the natural environment should not only be created but be encouraged. Notable among such human interventions are afforestation, land reclamation, artificial fertilisation and irrigation schemes.
Precaution must be taken in implementing or carrying out such activities so that they do not create new environmental problems that will undermine the positive change they were intended for.