Consequences of Using Top Soil Rapidly

• Top soil is the nutrient-rich layer of soil that supports plant life. Jupiterimages/Photos.com/Getty Images

  Top soil is the layer of soil with high concentrations of organic materials and biological activity. It supports plant life and is extremely valuable in agriculture, natural ecosystems and overall planet health. Using up top soil without replacing the organic material, or replacing it with less organic matter than the amount that has been lost, degrades land quality.

Nutrient Depletion

• When crops are grown on a stretch of land, the farmer harvests a large percentage of the biomass grown there: his crops. In a natural system, the animals would return the nutrients in the form of manure, and the top soil would continue to build. However, in the case of crop production, the animals are humans, and waste from humans goes into sewage lines. This results in a constant net loss of nutrients from the top soil, and nutrients must be added from an outside source.

Erosion

• Farming and other horticultural practices involve a great deal of tilling of top soil, either to prepare the ground for a new crop or to manage weeds. This breaks up the top soil and exposes it to wind and water erosion, especially when crops are planted in rows to accommodate heavy machinery. This also compounds nutrient depletion from crops, because valuable top soil blows into freshwater systems and interferes with aquatic life, washes downstream and ends up in the ocean.

Loss of Beneficial Organisms

• Earthworms and other beneficial creatures live in top soil and improve it over time. If top soil is used rapidly, the beneficial organisms that depend on the top soil to survive die off or move on, ensuring that the depleted land remains a wasteland.

Increased Need for Fertilizers

• When top soil is used faster than it can be replaced, plants will begin to need extra nutrients to replace what they no longer get from a healthy, deep layer of top soil. With excessive use of fertilizers comes degradation of water quality from nitrogen toxicity or algae blooms in lakes from excess nitrogen or phosphorus runoff.

Increased Need for Pesticides

• Weeds become a nuisance because of their ability to grow in harsh conditions, stealing water, nutrients and sunlight from desirable plants. Weeds are nature's 'repair mechanism'. They invade areas with disturbed, low-nutrient top soil. Left alone, they slowly begin to rebuild soil and attract birds that replant native plants, restoring land. When top soil is used too rapidly in agriculture, weeds are a constant battle. Weed tillage results in more top soil loss and erosion, perpetuating the cycle.