What Is the Meaning of Leaching?

Save

The term "leaching" often comes up in discussions of soil and fertilizer. What exactly is leaching? In soil, leaching is a natural process that can be helpful or harmful, depending on the circumstances.

Definition of Leaching

  • Leaching refers to the process by which chemicals, nutrients and other soluble matter in soil are dissolved by excess water and washed away.

Leaching and Soil

  • Leaching of soil occurs naturally and is part of the process of soil formation. When soil becomes saturated with rainwater, water travels downward, into groundwater or into springs and eventually rivers, lakes and streams. In the process, substances such as iron, aluminum, calcium and organic matter are carried deep into the soil or washed away altogether.

Leaching Potted Plants

  • Leaching is a beneficial technique for washing excess salts and fertilizers from the soil of potted plants. When you apply fertilizer repeatedly to potted plants, salts from the fertilizer build up in the soil and can burn plant roots. You can sometimes see a ring of salt on the outside of clay pots or around the top of the soil. The College of Agriculture & Life Sciences at the University of Arizona recommends leaching potted plants every four to six months to prevent salts from accumulating. To leach a potted plant, pour approximately twice the amount of water as the pot can hold on the top of the soil and let it drain completely.

Nitrogen and Water Pollution

  • Leaching becomes a problem when pesticides and fertilizers from the soil are leached into water supplies. The leaching of nitrogen is of particular concern. Nitrogen, an important plant nutrient, occurs naturally in soil as a result of decomposing plant and animal matter and as a result of soil amendments such as animal manure and nitrogen fertilizers. During times of heavy rainfall, nitrogen is converted into nitrate, a mobile form of nitrogen which moves easily with the flow of water. When nitrate is leached into groundwater and streams, it becomes potentially harmful to pregnant animals and their young. When it enters private wells and water supplies, nitrate poses a threat to humans---especially babies less than 1 year of age. According to the University of Missouri Extension, nitrate poisoning in infants causes internal suffocation or "blue baby syndrome."

Organic Farming and Leaching

  • Organic farming methods can be helpful in reducing the amount of pesticides and nitrogen leached into water supplies. The USDA National Institute of Food and Agriculture reports that, in a study by Washington State University, nitrogen leaching was four to five times greater in trees fertilized using synthetic fertilizers than those fertilized using organic methods. Some ways you can reduce harmful soil leaching are by increasing the organic content of your soil, using natural slow-release fertilizers, and avoiding the use of pesticides whenever possible.

Related Searches

References

  • Photo Credit chemin boueux dans la foret image by Ingrid from Fotolia.com
Promoted By Zergnet

Comments

You May Also Like

  • Leaching of Soils

    Leaching of soil can be defined as the loss of any soluble substance (such as salts or nutrients) as well as colloids...

  • How to Leach From Potted Plants

    Potted plants have different requirements than those grown in the ground. One condition that occurs with potted plants is salt buildup in...

  • What Causes Soil Leaching?

    Soil leaching refers is the movement of nutrient elements from topsoil through the soil profile. Leaching causes significant nutrient losses, particularly in...

  • What Is a Soil Profile?

    A soil profile consists of four layers of soil called horizons. The O horizon, A horizon, B horizon and C horizon are...

  • What Are Leaching Foods?

    Leaching foods deplete the body of vitamins and minerals. They drain the body's vitamin stores by preventing absorption, breaking down nutrients or...

  • What Problems Can Fertilizers Cause?

    Fertilizer is a substance or mixture, made from either synthetic or organic methods, used to make soil more fertile. Fertilizer contains the...

Related Searches

M
Is DIY in your DNA? Become part of our maker community.
Submit Your Work!