Healthy soil is essential to the plants and crops we depend on and for all natural life to thrive. In recent years, our plant’s soil has become an area of concern for world leaders and farmers alike.
Why? Scientists say it takes up to 1,000 years to form one centimeter of topsoil, but this single centimeter can be lost entirely with one heavy rainfall if it’s not protected.
Several soil conservation methods exist to preserve our soil. These could be through agricultural practices or simply measures you take at home to live more of an environmentally-friendly lifestyle.
In this article, we’ll take you through the most impactful soil conservation methods practiced by farmers and at-home gardeners around the world and examine why these methods are critical for the survival of healthy soil.
What is soil conservation?
Before diving into the most effective soil conservation methods, let’s look at what soil conservation is, and why it’s important.
Farmers use soil conservation methods to prevent soil degradation, erosion, and the depletion of organic matter in the soil. Typically, these solutions aim to preserve and protect the soil for years while improving crop yields.
Aside from protecting soil from the adverse effects of pollution and deforestation, soil conservation also aims to maintain soil biodiversity in a given area. Some conservation methods ensure proper conditions for living microorganisms in the soil, a critical part of ensuring that healthy crops can grow and access the rich nutrients they need to thrive.
Why is soil conservation important?
Soil conservation methods work to prevent several harmful threats to our earth’s soil. These methods can prevent the negative effects of runoff, pollution, and sedimentation, and can even protect surfaces from cracking and erosion due to water, wind, and excessive heat.
There are several critical reasons why soil conservation methods are important to practice.
Combating soil degradation
Soil conservation methods typically aim to combat soil degradation, which is the physical, chemical, and biological decline in soil quality. The most common examples of soil degradation include:
- Decline in soil fertility
- Negative changes in salinity, acidity, or alkalinity of the soil
- Soil erosion
- Decline in the structural condition of the soil
- The effects of toxic chemicals, pollutants, and flooding
Soil erosion is worsened by human activity and is one of the biggest threats to our soil. Soil erosion is the erosion of the top layer of dirt, or topsoil, which is the fertile material vital to producing plants, trees, and encouraging other forms of life.
Soil erosion can be caused by a variety of factors, including large amounts of rainfall and runoff. When water floods into an area, it displaces critical topsoil. Deforestation also worsens soil erosion by exposing more soil to heavy rainfall and wind.
Soil erosion and other effects of soil degradation can permanently damage our land’s ability to grow crops and support life, which can be catastrophic for farmers and the populations that depend on their crops.
To maintain organic matter in the soil
In addition, soil conservation activities help to maintain an adequate amount of organic matter in the soil. Organic matter is critical to soil health in many ways, from increasing its resiliency to improving productivity and water-holding capacity. Organic matter improves the chemical, biological, and physical conditions of the soil.
Soil organic matter is the fraction of the soil that consists of plant or animal tissue in various stages of decomposition. Most soil ideal for agriculture production consists of 3-6% organic matter.
To secure food supplies
When soil is healthy and productive, crops and food supplies grow faster and become more readily available. Soil conservation increases the quality and quantity of long-term crop yields because it keeps topsoil in its place while preserving the soil’s biological and chemical productivity for years to come.
These methods ensure that farmers can grow enough food domestically and for others worldwide, where food shortages happen often. Soil conservation can play a part in preventing food shortages as well by ensuring that soil is usable.
Soil degradation costs farmers money due to lower crop yields and loss of nutrients from the soil. Around the world, soil degradation is anticipated to lead to $23 trillion in losses of food, ecosystem services, and income by 2050, according to the United Nations.
Conserving our soil is critical not only for the farms that depend on soil for income, but because the world relies on soil for almost all of our food production.
To improve water and habitat quality
Our soil and water sources are inextricably linked: all life forms need clean water to survive. Soil protects local water sources – when soil is degraded or erodes, waters are at a greater risk of contamination.
In fact, soil filters contaminants out of runoff before it flows into other water sources. As soil is lost, water loses its natural ability to filter. The result is that more contaminants reach our waterways, dangerously increasing pollutant levels in critical water sources like groundwater, which we use for drinking water.
By preventing contamination, preserving organic matter, and producing more productive crops, soil conservation also restores and improves natural habitats that animal and plant species rely on for fertile soil and healthy water.
What are the main soil conservation methods?
Now that we understand the critical importance of soil conservation, let’s dive into the most popular and effective methods of preserving this precious resource. Soil conservation methods typically rely on three basic steps:
- Obtaining proper knowledge of land resource use.
- Monitoring fields and detecting critical zones.
- Controlling the efficiency of soil conservation techniques.
Because soil conservation methods are typically done with long-term benefits in mind, monitoring and implementing these methods continuously over time is crucial.
1. Practice sustainable operations
Overall, the best action we can take for our efforts toward soil conservation methods is to practice sustainable agricultural operations.
- Not extracting soil from threatened habitats
- Avoiding the use of fertilizers and pesticides in agricultural operations
- Minimizing water use
- Selection of species and varieties that are well suited to the site and to conditions on the farm
- Diversification of crops and livestock
Farmers and at-home growers can use many other methods to create a more sustainable practice. While soil conservation is critical to practice as part of a sustainable operation, these additional factors also play a role in soil quality.
Our air, water, and soil are all interconnected resources, meaning that the harm done to one will inevitably impact the other. For example, deforestation is causing the soil to be eroded: the loss of many trees in an area can leave soil unprotected and prone to erosion. This is because vegetation and trees help keep the structure of the soil.
Today, global warming is impacting weather patterns, which has led to heavier rainfall and more extreme weather, which also plays a role in damaging soil. In this way, it’s clear that the actions we take to live and operate more sustainably will play a role in improving the quality of our soil.
2. Crop rotation
This soil conservation method involves growing various crops in a set order on the same land, with different rotations. So, rather than plant the same crop each year on the same land, this method involves planning out different growing seasons for different crops.
How does this method preserve soil?
If a farmer wants to boost the growth of their sugarcane crop, for example, they may decide to grow beans after they harvest the sugarcane. Why? Because growing sugarcane requires a lot of nitrogen, and beans add nitrogen to the soil.
By rotating the crops that are grown and harvested on the same land, farmers can ensure that the soil’s nutrients are balanced. These secondary crops can be hugely beneficial to soil quality.
To effectively rotate crops, farmers often divide plants and crops into subgroups based on their management needs, physical characteristics, growth patterns, and harvest times. Dividing land into a grid structure is also often helpful for crop rotation.
While it requires long-term planning, crop rotation can improve soil health and organic matter greatly. It can also reduce the need for fertilizer and pesticides, lowering costs and reducing the likelihood that these contaminants will find their way into water sources.
3. Practice mulching
The practice of mulching consists of applying organic material over exposed soil.
Aside from adding healthy organic matter to the soil, mulching has numerous benefits: it reduces soil moisture loss through evaporation and reduces the soil’s exposure to wind.
Mulch has an insulating quality, which helps keep the soil cooler in the summer and warmer in the winter. It also helps to reduce the effects of heavy rain and runoff and prevent soil erosion.
Mulch has an insulating quality, which helps keep soil cooler in the summer and warmer in the winter. It also helps to reduce the effects of heavy rain and runoff, and prevent soil erosion.
Natural wood chips, hay, and straw are the best mulching materials, because they are natural and will decompose into soil and enrich the health of soil over time.
Mulch needs to be replenished periodically and added to fields after harvesting late-season crops like carrots, potatoes, onions, and corn. Mulch should be applied to ensure at least 85% soil surface coverage.
4. Plant cover crops
Planting cover crops is one of the simplest soil conservation methods, but offers multiple additional benefits such as suppressing weeds and attracting pollinators. Cover crops are rotated with cash crops to blanket the soil all year round and produce green manure that replenishes nitrogen and other critical nutrients.
These crops are planted to reduce the impact of wind and water on bare soil. They reduce the speed of runoff, hold topsoil in place, and encourage more significant infiltration.
Sweet clover, alfalfa, rye, and winter wheat are common cover crops: winter wheat or rye are often planted to provide cover during the winter and provide erosion control during the spring when runoff occurs.
5. Contour plowing
Contour plowing involves planting crops in a way that utilizes the natural slope of hills. Instead of altering the structure of a hill, the farmer uses its natural slope.
In contour farming, a farmer plows the soil parallel to the hill’s contours, creating rows of small dams that minimize the loss of essential nutrients, organisms, and plants from the crops. Plowing the soil in this way also increases water filtration and improves crop yields by maintaining nutrients in the soil.
Contour plowing is most effective on slopes between 2 and 10%.
6. Cross slope farming
Cross slope farming is the practice of conducting field operations perpendicular to the slope of a field. These practices can include:
- Tillage and seeding,
- Planting strips of different crops, or
- Constructing division terraces, or shallow grassed ditches, across a slope to intercept surface runoff water moving down the field.
Cross-slope farming is a highly effective way to control large amounts of runoff that flow down a sloped field. It’s important to note that farming across a slope requires fields to be wide enough to farm efficiently and may require equipment modification to avoid side hill slippage on steep slopes.
Other soil conservation practices can also be effectively integrated with cross-slope farming.
7. Organic growing
Organic growing practices are a key part of sustainable agricultural operations, and also positively impact soil health. This method involves minimizing or eliminating the use of synthetic fertilizers and pesticides.
Instead, natural fertilizers will nurture soil more effectively than their synthetic counterparts. This is because fertilizers usually only replace macro-nutrients like phosphorus, nitrogen, and potassium, and do not provide the organic matter that natural fertilizers do. Not to mention synthetic chemical-based products harm our water supply.
In addition, most insecticides target pests, but can also kill insects and microorganisms that are essential to soil fertility. This soil conservation method can be practiced anywhere, from a backyard to large-scale agricultural operations, and our planet’s water and soil supplies will be better for it.
8. Conservation tillage
Tillage is a critical component of agricultural operations, but it’s been proven that minimizing mechanical operations and the disturbance of soil plays a large role in reducing soil erosion.
This is because tilling removes plant covering, leaving soil bare, decreasing the amount of nutrient-rich organic matter in the soil, and reducing its ability to absorb water and retain nutrients. Soil is also, unfortunately, more susceptible to erosion after tilling.
Conservation tillage, also referred to as minimum tillage, is a broadly defined practice that includes no-till, strip-till, ridge-till, and mulch till systems. In no-till farming, seeds are planted in narrow furrows, eliminating the need to plow.
These techniques aim to reduce tillage passes on land, implying zero or minimum disturbance to soil and planting seeds into the crop residue. Minimum tillage systems are so effective that they maintain plant residues on at least 30% of soil surface afterwards.
9. Use buffer strips
Conservation buffer strips are defined as a protective zone of permanent vegetation between a farm field and nearby waterway. This strip of land is vegetated with grasses or bushes, and is generally two to five meters wide.
The implementation of buffer strips is one of the most effective soil conservation methods, because the plant cover filters sediment out of runoff, holds soil in place, and protects the quality of the nearby water.
Aside from erosion control, buffer strips provide excellent wildlife habitat for small animals and insects. If forested, they can improve stream habitat by shading the water and making the environment more suitable to fish species like trout.
10. Bank stabilization
This method of soil conservation consists of any measure that holds soil in place on a bank of a body of water. The soil in these areas is particularly vulnerable to steam currents, surface runoff, and waves.
There are three common methods used to control stream bank erosion:
- Rip rap, or adding loose rock on a steep bank.
- Gabion baskets, or wire baskets filled with rocks that prevent movement.
- Re-vegetation, or planting natural grasses, shrubs, and trees that slow the movement of water over the soil.
These methods of bank stabilization reduce soil erosion, and also increase the soil’s ability to filter water passing through it. This soil conservation method is essential for soil near waterways and shores.
Why soil conservation methods matter
Effective soil conservation methods are crucial if we want to maintain healthy soil to sustain life on Earth. It’s clear that soil is a precious resource that must be preserved, both in domestic and commercial agricultural settings. To protect soil from degradation, and increase soil fertility, soil conservation methods are essential to practice.
From adding rich nutrients to soil to protecting soil from runoff, erosion, and wind, these soil conservation methods should be a part of any growing practice.
Whether you are hoping to live a greener lifestyle at home or want to conserve soil quality on your farm, these soil conservation methods are sure to help you accomplish your goals.