Environmental pollution

Water Pollution

• This is the introduction of contaminants into water bodies such as lakes, streams, rivers, oceans, groundwater, etc. Water is the second most polluted environmental resource after the air.
• Activities that lead to water pollution are disposal of solid waste into water bodies, discharge of untreated effluent, hot water discharge, runoff from irrigation sites, among others.
• Water pollutants include insecticides and herbicides, micro organisms, heavy metals, food processing waste, pollutants from livestock operations, volatile organic compounds, leachates, effluent, grey water, black water, chemical waste and others.
• Nutrient pollution, also called eutrophication, is an aspect of water pollution where nutrients, such as nitrogen, are added into bodies of water. These nutrients cause the excessive growth of algae to the extent that the algae consume all dissolved oxygen in the water. When the oxygen becomes exhausted, the algae die and the water begins to smell.
• The algae also prevent light penetration into water bodies. This creates an anaerobic environment that causes the death of aquatic organisms. The decomposition of these organisms reduces the oxygen level in water bodies.
• When these contaminants enter a water body from a single identifiable source, they are referred to as point source pollutants. If the water is polluted as a result of the cumulative effects of different amounts of pollutants, non-point pollution has taken place. Groundwater pollution occurs through infiltration and affects groundwater sources such as wells or aquifers.

Land Pollution (soil pollution)

• Land pollution is a reduction or decline in the quality of the earth’s land surfaces in terms of use, landscape, and ability to support life forms.
• Soil Pollution takes place there is a large number of toxic chemicals, pollutants, or impurities in the soil.
• Improper solid waste disposal is a major cause of land pollution. These wastes do not only contaminate the soil but find their way into surface waters through runoff and groundwater as leachates. A high or low pH value changed chemical composition, loss of nutrients, presence of chemicals, fertilizers, pesticide, herbicides, etc. are the indicators of soil pollution.
• Other causes include massive cutting of trees, agricultural waste, earthquakes, volcanoes, floods, mineral exploitation, improper waste disposal, accidental oil spills, acid rain, construction activities, etc.
• Effects of land or soil pollution include change in soil structure, biodiversity loss, poor soil quality and loss of arable land, contaminated food chain, general health crisis, etc.