If you've read our articles on water pollution and air pollution, you'll know that pollution can be defined generally along these lines: it's the introduction into the environment of substances that don't normally belong there, which, in great enough concentrations, can have harmful effects on plants, animals, and humans. [1] We can define land pollution either narrowly or broadly. Narrowly defined, it's another term for soil contamination (for example, by factory chemicals or sewage and other wastewater). In this article, we'll define it more widely to include garbage and industrial waste, agricultural pesticides and fertilizers, impacts from mining and other forms of industry, the unwanted consequences of urbanization, and the systematic destruction of soil through over-intensive agriculture; we'll take land pollution to mean any kind of long-term land damage, destruction, degradation, or loss.There are many different ways of permanently changing the land, from soil contamination (poisoning by chemicals or waste) to general urbanization (the systematic creation of cities and other human settlements from greenfield, virgin land). Some, such as huge landfills or quarries, are very obvious; others, such as atmospheric deposition (where land becomes contaminated when air pollution falls onto it) are much less apparent.