Soil can become polluted in a number of different ways and much land becomes damaged each year as a result. The main causes of soil pollution are poor management of the land in farming, mining and quarrying, disposal of household and factory waste as well as road traffic.
We need to be aware that soil pollution affects not just ourselves but also the animals and plants with whom we share the planet.
The main problem on modern intensive farms is the increased use of and dependence on chemical fertilisers, pesticides and insecticides. If applied in the wrong strengths, these can remain in the soil, and will also leach off the fields and into local water supplies. A frequently-ingredient in fertiliser is nitrogen which, if left in a heavy concentration in the soil can actually alter the acidity, or pH, and so change the variety of plants able to grow in that environment. Both agricultural crops and the natural vegetation can be affected by polluted soil. Some of the poisons are taken up by the plants and animals we eat and so enter our bodies. This can lead to cancers and a wide variety of other illnesses. Responsible farmers are able to regulate the amounts of fertilisers and pesticides being applied so as not to cause these problems.
Mining and quarrying
Mining waste is generally left on site in the form of spoil heaps. These spoil heaps may contain a wide variety of toxic, or poisonous substances which then leach into the soil due to rainfall, or are blown around by wind. This can have a great impact on the regeneration of vegetation on the site.
Disposal of household waste
As a nation we produce vast quantities of household waste every year, much of which could and should be recycled or allowed to degrade naturally. Much of our waste is either incinerated - with potential problems of air pollution - or buried in landfill sites, where leaching of waste builds up problems for the future.
Heavy industry often produces quantities of unwanted chemicals, which, if allowed to come in contact with the soil, can cause extensive pollution. If cleaning agents such as detergents are released irresponsibly, they can cause pollution both to the soil and again to the water supplies. Underground storage tanks can be a major source of pollution if they should leak.
Vehicles are a major cause of pollution to the soil close to roads, especially where vehicles are running on the old leaded petrol.
What can be done about soil pollution?
Cleaning up polluted soils is often possible, but is very expensive. It is important to take whatever steps are possible to prevent the damage occurring in the first place.
In our own families we can help by checking to see if the family car will run on unleaded petrol, and making car journeys only when necessary. We should also dispose of waste products responsibly after changing the engine oil. We should recycle everything we can and make garden compost of all suitable vegetable and plant waste. Try to put as little as possible in the dustbin for disposal by the Council to landfill.
Many people buy organic foods, grown without the use of artificial fertilisers and pesticides. We need, perhaps, to be less concerned with the perfect size and shape of the fruit and vegetables in our supermarkets, and more concerned about the methods used to achieve this perfection!