SHE

CONSERVATION AND POLLUTION (3 UNITS)

This course is centred on two sections viz
(A). Natural Resources of the world with emphasis on Nigeria, the values, utilization, destruction and principles of management.
(B). Concept of pollution, pollutants, and their biological effects, environmental Impact Assessment, control and future prospects.

CONSERVATION OF NATURAL RESOURCES
This aspect deals with section A above ie Natural Resources of the world with emphasis on Nigeria, the values, utilization, destruction and principles of management.

NATURAL RESOURCES
What is a resource?
A resource is anything that is valuable to man. It could be a living thing or non-living thing. It could be gaseous, liquid or solid.

Occurrence of Natural Resources
Natural resources are not man-made. They occur in nature within environments that exist relatively undisturbed by man. A natural resource is can be viewed jn terms of biodiversity and extant geodiversity in various ecosystems. Biodiversity refers to the totality of various forms of living organisms in a given locality. It refers to various genotypic and phenotypically expressed traits in animals, plants, bacteria, viruses, and fungi in a locality. The foregoing shows that biodiversity is a measure of the variety of organisms in different ecosystems. By extension this refers to genetic variation, ecosystem variation, or species variation (number of species) within an area, a biome or planet.
Geodiversity is the variety of earth materials, forms and processes that constitute the planet Earth and shape it. Relevant materials include minerals, rocks, sediments, fossil, soils, and water. Forms may comprise folds, forms, faults and landforms as well as other expressions of morphology or relations between units of earth material.
An ecosystem is a community of living organisms including plants, animals and microbes in conjunction with the non-living components of their environment including the air, water and mineral soil, interacting with one another as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems can be of any size but usually encompass specific, limited spaces.
Natural resources are derived from the environment. Some of them are essential for our survival while most are used for satisfying our needs. Natural resources may be further classified in different ways.
Natural resources are materials and components (something that can be used) that can be found within the environment. Every man-made product is composed of natural resources (at its fundamental level). A natural resource may exist as a separate entity such as fresh water, and air, as well as a living organism such as a fish, or it may exist in an alternate form which must be processed to obtain the resource such as metal ores, oil, and most forms of energy.
Some natural resources such as sunlight and air can be found everywhere, and are known as ubiquitous resources. However, most resources only occur in small sporadic areas, and are referred to as localized resources. There are very few resources that are considered inexhaustible; these are solar radiation, geothermal energy, and air. The vast majority of resources are exhaustible, which means they have a finite quantity, and can be depleted if not well managed.

Classification of Natural Resources

Natural Resources can be classified using the following criteria:

1.      Origin

2.      Stage of Development

3.      Renewability

On the basis of origin, natural resources can be divided into:

A.      Biotic – Biotic resources are obtained from the biosphere (ie living and organic materials), such as forests and animals, and the materials or products that can be obtained from them. Please note that fossil fuels such as coal and crude oil belong to this category  since they are formed from decayed organic matter.

2. Abiotic – Abiotic resources are those from non-living, non-organic material. Examples include land, fresh water, air and heavy metals including ores such as gold, iron, copper, silver etc.

On the basis of their stage of development, natural resources can be divided as follows:

A.      Potential resources – Potential resources are those that exist in a region and may be used in the future. For example crude oil (petroleum) occurs with sedimentary rocks in various regions, but until the time comes when it is actually drilled out and put into use, it remains a potential resource.

2. Actual resources – Actual resources are those that have been surveyed, their quantity and quality determined, and are being used in presently. The development of an actual resource, such as wood depends upon the technology available and the cost involved.
3. Reserve resources – The part of an actual resource which can be developed profitably in the future is known as a reserve resource.
4. Stock resources – Stock resources are those that have been surveyed but cannot be used by organisms due to lack of technology.

On the basis of Renewability natural resources can be grouped as either renewable or non-renewable:

A.      Renewable resources: Renewable resources are those that can be replenished through natural processes. Some of these resources, like sunlight, air, wind, etc., are available continually and their quantity is not noticeably affected by human consumption or exploitation. Viewed from a human use perspective resources are classified as renewable if  the rate of replenishment or recovery exceeds that of consumption.

Non-renewable resources:  These are resources that either form slowly or do not naturally form in the environment. Minerals are the most common resource included in this category. From the human use perspective, these resources are non-renewable when their rate of consumption exceeds the rate of replenishment or recovery; a good example of this are fossil fuels, which are in this category because their rate of formation is extremely slow, running to millions of years hence, they are considered non-renewable. 


To be updated soon.