Did you know that 87% of life on Earth is sustained by just 39 inches of topsoil? The usable topsoil we have left is rapidly decreasing; over the past 40 years, we have lost 40% of our topsoil. According to the United Nations, we have only enough soil left for approximately 80 to 100 more harvests, equivalent to just 45 to 60 years of agriculture. This is a deeply concerning reality, as soil degradation not only impacts our ability to grow food, but also has far-reaching consequences for the environment and local communities. Let’s explore the causes and consequences of soil degradation, and what we can do to protect and restore this vital resource.
Why are we losing ground?
One of the major causes of soil degradation is the overuse of chemical fertilizers and pesticides. These substances are used to promote plant growth and protect crops from pests, but their excessive use can disrupt the balance of microorganisms in the soil and lead to the loss of vital nutrients. This can result in reduced crop yields and negative impacts on the environment and local communities.
Another factor that contributes to soil degradation is monoculture, or the cultivation of a single crop over a large area. This practice can reduce the diversity of microorganisms in the soil and make it more vulnerable to erosion and nutrient depletion. It can also lead to the overuse of chemicals, as farmers may rely on them to protect their crops.
The dirty byproducts of soil degradation
Soil degradation has serious consequences for agriculture and the environment.
Decreased crop yields: Soil degradation can lead to decreased crop yields, as the soil becomes less fertile and less able to support plant growth. This can have serious consequences for food security and livelihoods, particularly in areas where agriculture is the main source of income. For example, soil degradation in the Sahel region of Africa has been linked to overgrazing, overuse of land, and a lack of proper management practices. According to the United Nations Convention to Combat Desertification (UNCCD), approximately 85% of the land in the Sahel region is degraded to some extent. This has led to decreased crop yields, food insecurity, and poverty in the region.
Erosion and landslides: Soil erosion is the process by which soil is carried away by wind or water, leading to a loss of topsoil and reduced soil fertility. Erosion can be exacerbated by soil degradation, as the soil becomes less able to hold onto moisture and nutrients.
In extreme cases, erosion can lead to landslides, which can cause damage to infrastructure and loss of life. For example, landslides caused by soil erosion have been a major problem in the Philippines, particularly in the aftermath of natural disasters such as typhoons. According to the United Nations Office for Disaster Risk Reduction (UNDRR), landslides were the second leading cause of disaster-related deaths in the Philippines between 2000 and 2019. Soil erosion has also been linked to the loss of agricultural land and decreased crop yields in the country.
Water pollution: Soil degradation can also contribute to water pollution, as the loss of soil structure and nutrients can lead to the leaching of chemicals into groundwater and surface water. This can have serious consequences for human health and the environment. For example, agricultural runoff from soil erosion has been a major contributor to water pollution in the Chesapeake Bay in the United States. According to the Chesapeake Bay Foundation, agricultural practices, including the use of fertilizers and pesticides, are the leading source of pollution in the bay. Soil erosion from agricultural land has also been linked to the loss of habitats for fish and other aquatic species in the bay.
Loss of biodiversity: Biodiversity loss is an unfortunate result of soil degradation, as the loss of soil structure and nutrients can make it less suitable for supporting a diverse array of plant and animal life. This can have serious consequences for ecosystems and the services they provide, such as pollination and pest control. For example, soil degradation due to the overuse of pesticides has been linked to declines in populations of bees and other pollinators in the United Kingdom.
Solutions to soil degradation
But it’s not too late to turn things around. There are many ways that we can work to restore and protect our soil, including the following:
Conservation Tillage: Conservation tillage is when farmers minimize the amount of soil disturbance during farming to help preserve the soil structure and reduce erosion. This can be done through practices like no-till farming, where the soil isn’t plowed or tilled before planting, and reduced tillage, where the soil is tilled less than in traditional farming methods.
Crop Rotation: Another solution is crop rotation, where farmers plant different crops in a specific order over time. This helps to improve soil fertility and reduce pests and diseases. For example, rotating between nitrogen-fixing crops, like legumes, and non-nitrogen-fixing crops, like cereals, can add nitrogen to the soil and improve fertility. Crop rotation can also break the life cycle of pests and diseases that are specific to certain crops.
Cover Crops: Cover crops, like legumes and grasses, can be planted to protect the soil from erosion and improve its fertility. These crops are often planted between main crops or in the off-season, and they help to stabilize the soil surface and intercept rainwater to prevent erosion. They also add organic matter and nutrients to the soil as they decompose, improving soil fertility.
Composting: Composting is another solution, which is the process of decomposing organic matter, like food scraps and yard waste, to create a nutrient-rich soil amendment. This helps to recycle nutrients and organic matter back into the soil, improving its structure and fertility.
Integrated Pest Management: Integrated pest management is a sustainable way to manage pests and diseases, using a variety of techniques like biological controls and reduced pesticide use. This can involve releasing predatory insects to control pest populations, using trap crops to attract pests away from main crops, and using pest-resistant crop varieties.
Water Conservation: Water conservation is important to reduce the amount of water needed for crop production and prevent soil erosion caused by over-irrigation. Water-saving techniques like drip irrigation can be used, as well as mulching to retain moisture in the soil and water harvesting, which involves collecting and storing rainwater for use in crop production.
Soil Erosion Control: To control soil erosion, physical barriers like terracing or windbreaks can be used. Cover crops and conservation tillage can also help to reduce soil disturbance and stabilize the soil surface. Other measures include using erosion-resistant crop varieties, establishing buffer zones around bodies of water, and implementing proper drainage systems.
What can we do to help?
Here are a few ideas for calls to action that people can do at home to protect soil:
- Start composting! By composting your food scraps and yard waste, you can help to recycle nutrients and organic matter back into the soil. Need some help getting started? Organizations like R City can help you along your compost journey!
- Use less water when watering your plants and lawn, and consider implementing water-saving techniques like drip irrigation. Over-irrigation can lead to soil erosion and the depletion of groundwater resources.
- Support sustainable agriculture by choosing products that are grown using practices that protect soil health, such as organic farming or regenerative agriculture.
- Use pesticides and fertilizers sparingly, and consider using natural alternatives when possible. Excess use of these chemicals can have negative impacts on soil health.
- Plant a tree or shrub in your yard to help stabilize the soil and intercept rainwater to prevent erosion.
Next time you think about the food on your plate, remember that it starts with the soil. Let’s work together to protect this vital resource for future generations.