While clean air, clean water and climate change dominate environmental discourse, the very earth on which we set our feet sometimes goes unnoticed. The truth is that land pollution is as much a threat to humanity – and all life – as other ecological ailments. Population pressure, modern technologies and carelessness all undergird the causes of land pollution. On a positive note, many of these agents of spoliation are simple to address…and even to reverse. Identifying them is the first step in doing so.
Cutting down trees to clear space for human activity is the heart of deforestation. Land that once enjoyed forest cover is now exposed, compacted by heavy machinery and otherwise paved. Wheteher for logging, construction or farmland, deforestation ranks as one of the major causes of land pollution.
Often, cleared land is not used in its entirety, leaving “wasted land” in its wake. With trees removed, the soil erodes more easily. Runoff from nearby commercial establishments can carry chemicals and waste product. After a period of time, the land is incapable of ever growing trees again.
2. Intensive Agriculture
Agriculture is normally thought of as a good thing. Some grow food for the rest, who go on to create a civilization. Yet many intensive practices of commercial agriculture serve as causes of land pollution. Chemical fertilizers – and even natural ones, like manure – are sometimes responsible for unhealthy concentrations of ammonia and nitrogen oxide in the soil.
Tractors and combines are heavy equipment that can compact the soil, destroying drainage capacity and nutrient transportation. Scientists call this phenomenon densification, whereby moisture can no longer reach the roots of crops. Compaction can occur during tillage, cultivation and harvest. Farmers understand how compaction hurts their business and many regulate how often their machinery passes over the fields. Others opt for lighter tractors.
3. Construction and Industry
Of the myriad causes of land pollution, construction, industrial production and demolition are a potent trifecta. Even with laws in place against illegal dumping and hazardous waste disposal, many enterprises skirt the rules and improperly discard fluorescent lights, rubber tires, motor oil and other non-biodegradable items. When dumped in wooded areas, along streams or in unauthorized landfills, such remains are toxic to soil and to wildlife.
When demolished buildings are inadequately removed, here too is land pollution. Leaving behind asbestos amterials, concrete, plaster board and asphalt not only creates a visual blight, it exposes children and passers-by to potentially hazardous substances. Again, governments codify management of these sites but such problems continue due to oversight or negligence.
4. Glutted Landfills
Although millions of people diligently recycle all kinds of articles – aluminum cans, plastic bottles, newspaper, cardboard – they must throw away even larger volumes of garbage. This refuse finds its way to landfills, which are fast becoming stuffed to capacity. To solve this problem, public authorities must establish new landfills. Imagine the trash populating a nearby dumpster instead sitting beneath the ground. How can this benefit the soil?
On the other hand, there are ways to mitigate the harm landfills cause. In sanitary landfills, the contents are completely segregated from the adjacent soil until their constituent elements are broken down–physically, chemically and biologically. To qualify as sanitary, the linings must demonstrate that they are impermeable, i.e. that no leaching can occur. In addition, their designs must ensure the ability to verify ongoing decomposition. Thirdly, regular monitoring by trained professionals is mandatory. Finally, their total area should be minimized by dense layering.
Extracting minerals, ores and precious metals from the earth is a longstanding industry that provides employment and economic boons from Australia to West Virginia to mainland China. Unfortunately, mining also degrades the soil, air and water of surrounding areas. As one of the contributing causes of land pollution, open pit mining is particularly dangerous. Crushing hardrock exposes radioactive and otherwise noxious substances, mixing them with slurries that penetrate soil and bedrock.
The use of mercury as an amalgamating catalyst in underground mining carries its own set of hazards. Improperly contained, this poison penetrates sediment and invades waterways. Often, mercury is fatal to vegetative growth.
6. Sewage Processing
On the face of it, sewage treatment seems to have no downside. In reality, it counts among the causes of land pollution. That may sound like an odd assertion, since sewage travels primarily by water. Yet water and land interact constantly. As a consequence, wastewater that is only partially treated can contaminate creeks, rivers, surrounding flora and the fauna that consume it.
While public utilities are heavily regulated with regard to sewage treatment, some solids make it through the safeguards. For example, a British study uncovered hundreds of thousands of plastic micro-fibers released from a single load of laundry. To be sure, land pollution consists of many elements for which we fail to look.
7. Nuclear Waste
The power of the atom holds much promise and much dread. While advocates of nuclear power celebrate its atmospheric cleanliness–no carbon emissions–critics remind them of past accidents and the devastating environmental aftermath. Setting aside the concerns over malfunction, nuclear production links to pollution in the form of waste like uranium mill tailings and spent reactor fuel.
Because of its radioactivity, waste is stored for long periods so to render its dangerous components non-threatening through decay. Even with such security measures in place, nuclear power facilities lawfully pour contaminated water (used in nuclear production) into rivers and channels. Yes, the levels of toxicity meet government standards. Contaminant accumulation on river banks and surrounding biomes, however have untold effects.
Pollution of soil and bedrock, of landscapes and vistas, are every bit as urgent as that of air and water. As noted, the interface of land, sea and atmosphere means that corruption of each affects the other. Careful management of waste – as well as its overall reduction – will foster not only a healthier terra firma, but also improve the air we breathe and the water we drink. Responsible stewardship of natural resources is a holistic and inter-connected global enterprise.