Chapter 9: Endangered Ecosystem

Human activities that threaten the ecosystem includes the following unplanned development and mismanagement of the ecosystems such as

(a) soil erosion
(b) flash flood
(c) landslide
(d) eutrofication
(e) water, air, thermal and noise pollution
(f) global warming
(g) ozone depletion
(h) climatic change
(i) extinction of living things
(j) deforestation

• Pollution causes the following effects

a) Deteriorate the human health by affecting the respiratory system and causing skin problem, conjunctivitis, cancer and cholera

b) Destruct habitats of plants and animals

c) causes the corrosion of buildings

d) Changes the climate through global warming

• Air pollutants include carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen oxide, dust, lead compound and heavy metals like zinc and mercury
• Main sources of water pollutions are

a) Domestic waste

b) Industrial waste

c) Agricultural waste

d) Oil spills

• The main sources of air pollution include

(a) Factories
(b) Vehicles
(c) Open burning

(d) Electric power station

(e) Use of inorganic agrochemical substances.

• Rivers are polluted by the rubblish and domestic sewage thrown into them.
• This leads to the reproduction of micro-organism and increases the biochemical oxygen demand (B.O.D). The decrease in available oxygen in the rivers causes the death of aquatic plants and animals.

• The green house effect leads to global warming.
• Increase in such gaseous pollutants as carbon dioxide, carbon monoxide and methane leads to this phenomenon.
• These green houses gases trap the heat from the sun and increase the global temperature.

• The ozone layer is present in the stratosphere.
• The ozone layer acts as shield against the harmful ultra violet rays by absorbing it. Earth inhabitants are thus protected from the ultra-violet rays that can cause cataract of the eye and melanoma (skin cancer)
• The thinning of the ozone layer is due to the effect of chloroflurocarbon (CFC)
• Developmental processes are require to

(a) improve the standard of living of the people economically and socially so as to improve the quality of life.
(b) Vary the sources of energy
(c) Maximise agricultural and industrial production
(d) Use the natural resources optimally.
The exponential increase in population leads to
(a) an increase in the requirement of water, food, places to reside and sanitation.
(b) pollution of the environment - air, water,
thermal and sound pollutions.
(c) Deterioration of the standard of living.
(d) Depletion of the natural resources.

• Well planned and managed development as well as good management of the ecosystem is essential to maintain a balanced environment.
• This ensures the survival of fauna and flora.
• The following steps should be taken to achieve the above.

(a) Enforcement of the relevant laws (implementation of the laws)

(b) Use of technology

(c) Education on the management of resources, including the reduction, reuse and recycling of resources.

(d) Preservation and conservation of soil, water, flora and fauna of forests and mangrove swamps.

(e) Practice of biological control

(f) Use of renewable energy

(g) Efficient use of energy