95% of the food we eat comes from the soil, so it is important that we take care of it!
“Natural disasters, such as storms, volcanos, fires, and floods, can disturb soil communities; however, human activities, such as development, clearcutting, growing monocultures, tillage, pollution, and the use of chemicals (pesticides, fertilizers) including the ones used in backyard gardens, contribute a lot more to soil degradation,” Christine Gust of Soil Transformations says. Soil degradation is the decline of soil quality which diminishes the soil’s capacity to support plants and animals.
Sadly, soils today are being degraded at an alarming rate, meaning that the soil food webs are weakening and our soils are losing vital nutrients and bacteria. But even with this reality, there are actions we can all take that conserve and regenerate the health of our soils.
One physical component of soil degradation is erosion.
Soil erosion is the loss of the topsoil, the top layer of soil, rich with organic matter and microorganisms, teeming with life. This is where the action happens. Soil erosion occurs naturally, when wind and water pick it up and transport it, disturbing the living community within the topsoil. The process is accelerated when plants are removed, leaving the soil exposed with no roots to anchor it down. Deforestation, development, and conventional agricultural practices can contribute to soil erosion. For example, when a field is tilled or plowed after a season of growing, and is left exposed to the elements without anything growing in it, it is vulnerable to erosion.
Soil is a renewable resource, but it doesn’t form as quickly as we use it. It can take 500 years for one inch of topsoil to form, yet it is estimated that 26 billion tons of fertile soil are lost due to erosion.
In addition to soil erosion there are also biological and chemical processes that can degrade the soil, like the use of chemical fertilizers and pesticides.
During our chat with Christine, she discussed some of the agricultural practices that can protect the soil from degradation and some that can regenerate and improve the quality of the soil-
Cover Cropping. At the end of a growing season, farmers might plow their fields, churning the soil and the microbiome to the surface, leaving it exposed to the elements. Cover crops can be planted to cover the soil and manage soil erosion, rather than for the purpose of being harvested. They can also provide wildlife habitat/ food and add nutrients to the soil, increasing soil fertility.
Mulching. In the fall, leaves fall on the ground to protect the soil over the winter and feed it beneficial nutrients. This is nature’s way of mulching! Mulching with straw, wood chips, cardboard, and a variety of other materials is a great way to prevent soil erosion and maintain a healthy soil environment. Mulching your home garden beds is a great way to care for your soil, as well as leaving leaves on the ground to break down and return to the soil!
Smart Tilling. Tilling is churning the soil and preparing it for the next round of planting. It can sometimes be dangerous because tilling too frequently or too deep (made possible by heavy machinery) can lead to erosion, loss of nutrients and reduced water retention. But Christine mentions that some tilling can also be good because it releases nutrients, allowing them to become available to plants. Some farmers use ‘low-till’ methods, like using a broadfork instead of a tractor, to aerate the soil while still maintaining the soil structure. You can also practice low-till methods in your home garden when clearing your beds for the winter. Cutting plants back to the surface of the ground, instead of pulling them out with their roots, maintains the soil structure and contributes nutrients to the soil as the roots die and break down.
Composting. Because plants feed on nutrients in the soil, crop production can deplete soils. In order to maintain a healthy soil and continue growing crops, it is important for farmers to use compost in their fields. Compost increases organic matter in the soil, which makes for a flourishing soil microbiome and can lead to healthier plants. Soil testing and creating a custom compost or compost tea based on the soil’s makeup can reduce the need for chemical fertilizers because the soil is getting just what it needs!
So, how can we ensure we are supporting farms that use soil-sustainable practices that help protect our soils from degradation? Christine recommends getting to know your farmers! You can start buying locally-grown food at farmer’s markets or from a nearby CSA. And if you are already buying food locally, try chatting with your farmer about the practices they use on their farm!
To learn more about the future of soil and soil conservation, continue reading in Soil Series Part 3!
