According to Chauhan (2015) environment involves everything that affects an organism during its lifetime. It can simply be defined as one’s surrounding. It refers to the sum total of conditions which surround man at a given point in space and time. J.E. Otiende, W.P Ezaza and R.Boisvet (2014) give several definitions of environment including; the social and natural surroundings including ourselves, our actions and interactions, the atmosphere, land, and wildlife.
Environmental conservation refers to man’s interactions with the environment such that he benefits from it while preserving it for the future either by improving it or maintaining the status quo.
How man benefits from the environment
It is in man’s ability to discover, in his physical environment the materials he needs to use in order to make his life on the surface of the earth possible (Otiende et al,2014). Man gets those materials from the earth’s atmosphere, lithosphere, and hydrosphere where they exist in form of matter or energy. These are man’s natural resources. The list of these natural resources embraces the earth’s climates, terrain features, materials of composition, natural vegetation and animal life.
A natural resource is any form of material (organic or inorganic) obtainable from the earth’s physical environment to satisfy human needs ( Otiende, 2014).
According to Chauhan (2015), resources are dynamics which not only improves new knowledge, expanding science and new technologies but also to changing the culture and social objectives. Chauhan(2015) notes that some resources such as solar energy, fresh air, fresh surface water, fertile soils and wild edible plants are directly available for us to us and other organisms while other resources such as petroleum, iron, groundwater and modern crops are not directly available and their supplies are limited. They become useful to us only with some effort and technological ingenuity.
The natural resources can be broadly categorized into renewable and non-renewable resources. It is no doubt therefore, that man is the greatest beneficiary of the environment and has, therefore, the greatest responsibility in conserving it. With proper utilization of the resources, man will continue reaping benefits from the environment which will sustain itself as long as man does not stretch it beyond its limit.
Human activities that destroy the environment
This sub-topic will attempt to examine how man, in his endeavor to satisfy his needs has continuously put the environment at stake and the possible measures he can engage in to mitigate the negative effects of his activities on it.
The United Nations conference on environment and development (UNICED, 1992) cited in Chauhan (2015), defines deforestation as, land degradation in arid, semi-arid and sub-humid areas resulting from various factors including climatic variations and human activities. Chauhan (2014) notes that, if the current rate of deforestation continues, the world’s largest forests will vanish the next 100 years causing unknown effects on global climate and eliminating the majority of animal and plant species on the planet.
The main effects of deforestation are:
- Soil erosion
- Sand deserts caused by strong unchecked winds
- Less rainfall leading to less natural rainfall
- Loss of biodiversity leading to disturbance in ecological balance
- Global warming due to increased carbon dioxide levels in the atmosphere.
The national forest policy (1952) stated that one-third of the geographical area of the country should be under forests. Currently, in Kenya, only 3% of the total arable land is covered with forests. However, all is not lost as a man can engage in the following activities to reduce deforestation and the negative effects on the environment:
- Discourage the use of firewood and instead go for alternative sources such as solar energy and biogas.
- Match the rate of felling trees with a functional tree planting program.
- A total ban or freeze on commercial tree falling for a period of about 10 to twenty years
- Creation of forests reserves where species of tree are protected.
- Creating awareness on the importance of conserving forests.
Interference with water.
Water is the source of life on earth in global terms, it is a rare liquid (Chauhan, 2014). It is the major constituent of the hydrosphere. According to an estimate by UN, about 2 billion people more than a third of the global population lack access to clean and safe drinking water. About 6000 children die every day from diseases associated with unsafe water and lack of sanitation.
The major human activity affecting inland fresh water is the degradation of these sources by the disposal of sewage and industrial effluents without treatment. Overuse of groundwater sources can cause several kinds of problems such as:
- A heavily pumped well can lower the water table as a result of which shallower wells go dry.
- Heavy pumping, on a broader scale, can deplete a whole aquifer.
- Excessive pumping of groundwater causes porous formations to collapse.
- Overuse of freshwater reservoirs along coastlines often allows saltwater to intrude into aquifers used for domestic and agricultural purposes.
However, man can employ the following measures such as those shown below:
- Reclamation of sewage and wastewater
- Development of groundwater, surface water sources and surface storage.
- Long range forecasting of rain.
- Transfer of surplus water.
- Desalination of water.
Minerals are non-renewable resources supplied by the planet to mankind. Human welfare and material supplies have been closely linked for centuries and they are naturally occurring inorganic earth materials processing certain physical and chemicals characteristics. Mineral resources are broadly defined as elements, chemical compounds, minerals or rocks that are concentrated in a form that can be extracted to obtain a usable commodity.
Nearly all aspects and processes of the geological cycle are involved to some extent in producing a local concentration of useful materials.
According to Chauhan(2014), the mining and processing of mineral resources usually have a considerable impact on land, water, air and biological resources; they also have a social impact because of the increased demand for housing and services in the mining areas. Some of the major environmental impacts of mining and processing operations are:
- Degradation of the land
- Pollution of surface groundwater resources due to the release of harmful trace elements (cadmium, cobalt, copper, lead and others) by leaching even if drainage is controlled.
- Serious adverse impact on the growth of vegetation due to leaching out of trace elements.
- Air pollution due to emission of dust and gases.
- Deforestation including loss of fauna and flora.
- Adverse impact on historical monuments and religious places.
- Physical changes in the land, soil, water and air associated with mining, directly and indirectly, affect the biological environment.
- Accidental or periodic discharge of low-grade pollutants through the failure of barriers or water diversions through breach of barriers during earthquakes, floods, etc.., also cause damage to the local ecological systems.
An ecosystem consists of plants, animals, and microorganisms which live in a definite zone along with the physical factors such as soil, water, and air. Within an ecosystem, there are dynamic interrelationships between the living forms and their physical environment. These relationships are manifested as natural cycles which provide to continuous circulation of the essential constituents necessary for life. These natural cycles and ecosystems operate in a balanced manner which stabilizes the entire biosphere and sustains the life processes on earth.