Kelab Alam Sekitar

What is land pollution?

Land pollution is the deterioration (destruction) of the earth’s land surfaces, often directly or indirectly as a result of man’s activities and their misuse of land resources.

It occurs when waste is not disposed off properly, or can occur when humans throw chemicals unto the soil in the form of pesticides, insecticides and fertilizers during agricultural practices. Exploitation of minerals (mining activities) has also contributed to the destruction of the earth’s surface.

Since the Industrial Revolution, natural habitats have been destroyed, and environments have been polluted, causing diseases in both humans and many other species of animals.

Human actions have also caused many large areas of land to lose or reduce their capacity to support life forms and ecosystems. This is know as land degradation. Note that land degradation can result from many factors, and land pollution is only one of them.

In the lesson, we shall see the more about Land and Environmental Pollution, the sources of the pollution, its consequences and a few things we can do to prevent further pollution and protect our environment.

Types of land pollution.

There are different types of land pollution. Many publications group them differently. Let us see these four main types:

Solid Waste
These include all the various kinds of rubbish we make at home, school, hospitals, market and work places. Things like paper, plastic containers, bottles, cans, food and even used cars and broken electronic goods, broken furniture and hospital waste are all examples of solid waste. Some of these are biodegradable (meaning they easily rot or decay into organic matter). Examples include food droppings, paper products as well as vegetation (like grass and twigs). Others are not biodegradable, and they include plastics, metals and aluminum cans, broken computer and car parts.

Because these do not easily decay, they pile up in landfills (a place where all the city’s rubbish are sent), where they stay for thousands of years. These bring great harm to the land and people around it. See the complete lesson on WASTE here.

Pesticides and Fertilizers
Many farming activities engage in the application of fertilizers, pesticides and insecticides for higher crop yield. This is good because we get more food, but can you think of what happens to the chemicals that end up on the crops and soils? Sometimes, insects and small animals are killed and bigger animals that eat tiny animals (as in food chains) are also harmed. Finally, the chemicals may be washed down as it rains and over time, they end up in the water table below (causes water pollution).

Chemicals
Chemical and nuclear power plants produce waste materials that have to be stored somewhere. Fertilizer, insecticides, pesticides, pharmaceuticals manufacturers also produce lots of solid and liquid waste. In many cases they are stored in an environmentally safe way, but there are some that find their way into landfills and other less safe storage facilities. Sometimes they also find their way into leaking pipes and gutters. They end up polluting soils and making crops harmful to our health.

Deforestation
Humans depend on trees for many things including life. Trees absorb carbon dioxide (a green house gas) from the air and enrich the air with Oxygen, which is needed for life. Trees provide wood for humans and a habitat to many land animals, insects and birds. Trees also, help replenish soils and help retain nutrients being washed away. Unfortunately, we have cut down millions of acres of tree for wood, construction, farming and mining purposes, and never planted new trees back. This is a type of land pollution.

Sources of land pollution.

Below are some sources of solid and semi-solid pollutants:

Agricultural sources:
These include waste matter produced by crop, animal manure, and farm residues. They also include the chemical left over of all pesticides, fertilisers and insecticides used for agricultural activities.

Ashes: The residual matter that remains after solid fuels are burned. When waste is burned in incinerators, two types of ashes are produced. Bottom ash is the debris from burnt metal and glass waste. Bottom ash are not bio-degradable. The second type of ash is called fly ash. This is the ash that is trapped by filters in the chimney of the incinerators. It is know to be very toxic (poisonous). Every four trucks of waste burnt produces about one truck of ashes that end up in the landfill too. Ashes easily leak into the soil and water tables causing land and water pollution.

Mining sources: This includes piles of coal refuse and heaps of slag and underground debris. Mining and forestry activities that clear the land surfaces (clearcutting) and use ‘skid trails’ often leave leave the land unrestored. The surface is exposed to erosion which destroys the quality of the land. Additionally, iron and other chemicals such as copper, mercury and lead from mining practices leach into the soil, polluting it and leaving it exposed to water bodies as well.

Industrial sources: These include paints, chemicals, metals and aluminum, plastics and so on that are produces in the process of manufacturing goods.

Sewage Treatment: Wastes that are left over after sewage has been treated, biomass sludge, and settled solids. Some of these are sent directly to landfills whiles other treatment plants burn them to generate electricity. Both end up polluting the environment.

Garbage or waste: These include household or municipal waste such as glass, metal, cloth, plastic, wood, paper, and so on. Some of these can decay and others cannot. They are usually collected and sent to landfills where the pollution action begins.

Construction sources: These include waste like debris, wood, metals and plastics that are produced from construction activities.

Deforestation: This is when trees are cut down for economic purposes, mining, farming and construction. In forests areas, trees absord and reflect about 20% of the intense heat from the sun, protecting and preserving its surface soils. Cutting down trees mean that the land is exposed to direct sunlight and rain, resulting in soil erosions, desertification and land degradation

Chemical And Nuclear Plants: These include chemical waste from chemical industries that are disposed off into landfills.

Oil Refineries: When crude oil is refined into usable petro, gas or diesel, there are by products that end up as waste.

 

Filed under: Articles on April 1st, 2014