World Soil Day: The Importance of Soil and Why We Need to Protect it
Updated: Dec 29, 2020
Today is World Soil Day, as designated by the United Nations as a day to raise awareness on the importance of maintaining and improving the health of soil for the greater good of the planet and human wellbeing. It wasn’t until I took a soil science class in undergrad (by far my favorite classes) that I began to appreciate just how truly amazing soils are.
Soil is the very foundation that makes life possible! Soil provides plants with foothold for their roots and the necessary nutrients to grow. It acts as a water filtration system to filter excess rainwater, preventing flooding; and it buffers against pollutants, thus protecting groundwater quality. Soil stores carbon, making it critical for fighting climate change. Additionally, soil provides humans with construction support and manufacturing materials, such as bricks used to build our houses from clay. Not to mention that it provides a habitat for billions of microorganisms.
I wanted to dedicate a blog post to bringing awareness and education on the critical importance of soil for life here on Earth, while also providing ways in which we can work to protect soil quality and fight against soil biodiversity loss. If this interests you, read on!
Why Soil is So Important:
• Soil is home to more than 1/4th of the Earth's biodiversity
• 95% of our food comes from the soil
• Soil captures more carbon than trees
• There are more living individual organisms in a tablespoon of soil than there are people on Earth (absolutely insane!)
• Most of the antibiotics used today to fight disease are obtained from soil microorganisms
• It takes 500 years to produce one inch of soil (crazy)
But LISTEN UP: Soils are being eroded more quickly than they are being formed. 33% of Earth's soils are already degraded—at the current rate of soil degradation, the world could run out of topsoil in about 60 years.
Firstly, this is largely due to unsustainable agriculture practices, such as industrial farming methods of monocropping and intensive tilling. Monocropping is the act of growing a single crop year after year on the same land, without rotating through other crops or growing multiple crops on the same land. This results in depleting soil nutrients and weakening the soil structure, lessening the chance of healthy plant growth in the future. When soil structure and quality become poor, farmers have to rely on chemical fertilizers and pesticides to encourage plant growth and production. This causes a chain reaction of making the surrounding land more reliant on pesticides to fight off predators, thus locking in fertilizer/pesticide use for years to come in order for the farm land to be productive.
Other causes of soil degradation are land degradation due to urban expansion, lack of cover crops (crops that are primarily used to slow erosion and improve soil health rather than for the purpose of being harvested), and use of pesticides and synthetic fertilizers (not to be forgotten that these are mainly derived from fossil fuels). Synthetic fertilizers alter the composition of beneficial microorganisms, killing off these microorganisms and depleting soil of organic matter.
When soil is depleted, it becomes nutrient deficient. This is a threat to global food security as most of our food is less nutritious than it used to be, resulting in the mineral and vitamin deficiencies many people face today. Soil erosion also means less plant life can be supported, meaning less carbon can be captured, exacerbating climate change.
How Individuals Can Help Prevent Soil Erosion:
1. Plant a variety of crops in your garden/plant bed as more plant biodiversity gives way to an increase in soil organic matter, while also reducing the amount of bare, exposed soil that is vulnerable to erosion.
2. Add mulch and rocks in your plant beds to reduce runoff.
3. Don’t overwater your plants, as doing so can speed up erosion by washing away soil.
4. If you’re planting on a slope, build a retaining wall to prevent soil from being washed downhill.
5. Avoid excessive soil compaction by staying on marked trails when walking/running, especially when it has just rained as soils are more vulnerable to erosion when wet.
6. Opt for organic fertilizer over synthetic fertilizer.
How to Prevent Farmland Erosion:
1. Agroforestry: Integrating trees and shrubs with other crops to hold soil in place and improve soil fertility.
2. Reducing tillage: Doing so causes less disruption to soil structure, which reduces the amount of surface runoff and soil erosion.
3. Crop rotation: The planned sequencing of crops over time on the same field, which can improve soil nutrient levels and break crop pest cycles, meaning less pesticides have to be used.
4. Cover cropping: Growing specific crops (such as ryegrass or clover) for the purpose of suppressing weeds, managing soil erosion, and improving soil fertility to promote biodiversity.
5. Integrated Pest Management (IPM) systems: Reducing reliance on chemical pesticides by managing pests (below an economically damaging level) rather than seeking to eradicate them; relying on biocontrol, such as using one biological species to reduce populations of a different species; and lastly, using chemical pesticides only when necessary in a way that minimizes their negative effects.
6. Using compost or organic fertilizers over synthetic chemicals ones.
I hope you found this informative and that you gained an appreciation for all the incredible things soil provides us with, as well as how critical it is that we prevent soil erosion to protect our soils.