A condition in the atmosphere where air parcels are heated and therefore are warmer than the surrounding atmosphere resulting in unstable weather conditions such as heavy rains and hailstorms. See Atmospheric Stability & Instability
Land Pollution & Degradation Causes, Effects & Prevention
Land pollution is the contamination or addition of impurities of land particularly the soil. The contamination of land then leads to land degradation. To distinguish between pollution and degradation, we will first list the causes of both land pollution and degradation and the causes of degradation without any prior pollution..
Causes of Land Pollution & Degradation
Causes of Land Pollution (Inexhaustive)
excessive use of fertilisers
Pesticides and herbicides e.g. Ethly dibromide (banned)
Oil spills, for example the Niger Delta in Nigeria is one of the most polluted place on earth
Improper disposal of industrial and domestic waste
In addition to the above causes of pollution which in turn result in degradation, degradation can also be caused directly without prior pollution
Direct Deforestation e.g. slash and burn
Direct mining e.g. open cast
Stream bank cultivation
Land over utilisation
Nuclear blasts and bombs
Effects of Both Land Pollution and Degradation
All of the above causes result in the same effects, but pollution results in degradation and degradation results from pollution. After pollution has taken place the effects will lead to land degradation.
One major cause of pollution and degradation is the deterioration of fertile lands into barren wastelands. Activities such as deforestation, over utilisation of land and excessive use of fertilisers can result in land becoming infertile which results in barrenness. Desertification has become a global concern. Many people across Africa have been negatively affected by desertification which has led to famines and hunger
Soil erosion & Mass Movements
Tonnes of soil is lost due to deforestation, land over utilisation and excessive irrigation again leading to infertility of land and desertification. In addition, this soil can find its way to rivers and choke them leading to floods
Deforestation results in unabsorbed carbon dioxide in the atmosphere which contributes to the greenhouse and further warms the globe
Fertilisers, pesticides, garbage as well as acid rain increases the acidity of the soil resulting in infertility. This results in food productions or poisoned harvests.
Depletion of species
Pollution and degradation results in certain species fleeing their habitats or dying. Deforestation can deplete birds and pesticides such as Ethyl dibromide (banned) can kill unharmful insects.
Endemic diseases such as cholera and typhoid can result due to land pollutions such as sewage burst. Soil acids or sewage can be washed away by running water into water bodies contaminating the water for drinking.
Bad odours can result from sewage bursts and dump
Measures and Mitigation
Some countries have successfully curbed or are trying e.g. China to reduce land pollution and degradation.
Some campaigns include Earth Day launched in 1970 which creates awareness and best practices on the environment. It is held every 22nd of April Almost 200 countries participate in this event.
Lets Do It! World Cleanup
was started in Estonia in 2008. 96 countries including Portugal, Italy and Slovenia have joined in.
In Zimbabwe, a National Cleanup Campaign was launched on 5 December 2018. The campaign was then declared to run every Friday of every first week of the month.
Most of these campaigns have been successful creating awareness and best practices among citizens.
Measures to Mitigate Land Pollution and Degradation
Fining industries and citizens on poor land practices
Substituting diesel & petrol vehicles with clean electric vehicles
Banning road unworthy vehicles
Avoiding excessive fertiliser and pesticide usage.
Recycling non-biodegradable materials such as plastics and diapers
Avoid littering and spitting anywhere. In Singapore, non -medical gum selling and chewing has been banned and comes with harsh penalties if you are caught. Australia introduced an organic swallowable gum
Avoid improper disposal of chemical objects such as batteries
Repairing damaged sewer, oil and chemical pipes
Measures to Mitigate Land Degradation
Afforestation and Reforestation projects to avoid erosion and desertification
Avoiding land over-utilisation and overgrazing. This can be achieved by proper land distribution and monitoring.
Avoiding excess irrigation as it can lead to water logging or salinity which both of these can result in acidic soils or erosion.
Avoiding stream bank cultivation as it can results in land subsidence and mostly chokes rivers with silt.
Gully reclamation projects by planting more plants
Using fire guards to guard against an eventual veld fire