Soil quality is affected by food, fiber, and feed production, and it’s directly linked to pollution, energy use, and global warming. The quality of soil around the world declines because of erosion, compaction, loss of biodiversity, and traditional crop management practices. When soil quality declines, crops lose their nutritional value and human health suffers.
A recent research study conducted by the American Academy for the Advancement of Science (AAAS) showed that organic farming delivers healthier, richer soil and nutritionally enhanced food. A panel of scientists tested their theories on apples, tomatoes, spinach, and other crops to determine the nutritional quality of the foods produced and the fertility of the soil after harvesting. They found that organic soil fertility methods use up less nutrients, which promotes more efficient assimilation of nutrients and translates into better plant health. The scientists also concluded that organic farming can often delay the onset of the dilution effect, which is a negative impact of chemical fertilizer.
Many studies have shown a direct correlation between human activity and soil health. Organic farming practices, such as crop rotation, help restore nitrogen balances in the soil and ensure long-term fertility. On the other hand, tillage practices increase carbon dioxide emissions and facilitate erosion. Animal manure has also been very influential in enriching the carbon content of soil.
Farmers can determine the quality of their soil by testing soil samples from various locations throughout the property. Physical properties, like bulk density and rooting depth, chemical properties, like pH and mineralizable nitrogen, and biological properties, like earthworms and enzymes, are recorded. Soil is a key component in increasing crop yields, so farmers will benefit by employing practices that make their soil sustainable for the future.
According to the U.S. Department of Agriculture, these are a few of the ways you can stabilize and enhance the quality of the soil on your farm and in your garden:
- Enhance organic matter to enhance water and nutrient holding capacity
- Avoid excessive tillage to prevent erosion
- Prevent soil compaction to provide crops with adequate air, water, and space
- Keep the ground covered with beneficial insects, earthworms, and cover crops
- Diversity cropping systems to control pests and prevent disease
To learn more about soil quality and how organic farming can improve it, check out The Organic Center’s Critical Issue Report: Soil Quality and Iowa State University’s Soil Quality in Organic Agricultural Systems.