Improve Soil Health: Essential Practices for Sustainable Agriculture and Ecosystem Resilience
The importance of your soil
As many already know, soil is essential for ecosystems to exist. It is often mentioned as the earth's skin holding roots, water, nutrients, organisms, and organic matter. Numerous species, such as bacteria, fungi, insects, and earthworms, play crucial roles in nutrient cycling, soil formation, and plant health. Each of these increases the resilience and productivity of ecosystems.
Nutrients, such as phosphorus, potassium, and nitrogen, are released through the breakdown of organic matter. This is done by a variety of intricate biochemical processes, and soil microorganisms release nutrients that plants require to develop. In exchange, vegetation cover lessens the impacts of water and wind and stabilizes healthy soils, thus preventing erosion. Also, soil's water storage capacity decreases the effects of droughts and floods. Crucially, healthy soils are like reservoirs, storing large amounts of organic carbon, thus mitigating global warming.
Impact of soil quality on your crops
Soil is a critical resource for agriculture, being the basis for food production to sustain livelihoods worldwide. Topsoil is especially vital to support plant growth as it provides nutrients. Stunted growth and reduced yields can be the results of nutrient-deficient soils. Additionally, soil pH affects nutrient availability to plants.: too acidic or alkaline soils hinder the plant's ability to absorb nutrients, affecting their growth and productivity. Next, the structure and aggregation of the soil affect root penetration, water infiltration, and air exchange. Healthy root development is encouraged by well-structured soils with adequate drainage and aeration. In other words, soils with high water holding capacity better withstand droughts and support steady crop development.
Moreover, organic matter content affects soil fertility by improving its structure, nutrient retention, and beneficial microbial activity. All of these promote healthier and more fruitful crops. Conversely, because of their smaller pore spaces, compacted soils restrict water infiltration, root growth, and penetration. Heavy machinery, poor land management techniques, or foot traffic can cause soil compaction. Next, pollutants such as pesticides, heavy metals, and industrial pollutants can harm soil quality. Contaminated soil hampers crop growth, negatively influencing food safety and posing risks to human health. Finally, erosion can deplete topsoil, lowering soil fertility, water-holding capacity, nutrient content, and thus crop yields over time.
Tools to assess your soil's quality
Several simple and affordable methods allow farmers to measure soil properties in their fields. This allows agricultural practices to be adapted to the local context and, therefore, ensures proper land restoration over the long run.
Visual Soil Assessments
Visual inspection can define soil properties like structure, colour, compaction, and root development. Simple field guides or assessment tools can be used for qualitative evaluation of soil health indicators, making it possible to pinpoint regions in need of improvement.
Soil testing kits
This portable tool is easy to use and measures key soil properties like pH and nutrient levels of nitrogen, phosphorus, potassium, and organic matter. Typically, the kits include test strips, color charts, or chemical reagents for on-site soil sample analysis.
Tea Bag Index (TBI) experiment
Tea bags can be used to measure soil organic matter dynamics and rates of soil decomposition.
This simple and standardized method involves burying tea bags for three to twelve months.
Soil pH meters
The soil pH meter is another tool for measuring soil pH. By putting probes into the soil, it measures the pH and displays the number on a digital screen.
Electrical Conductivity (EC) meters
An EC meter works similarly to soil pH meters but indicates electrical conductivity instead of pH. EC correlates with soil salinity and nutrient levels. High values suggest elevated salt or nutrient levels. In contrast, low EC values indicate poor nutrient availability.
Soil respiration tests
This test involves gradually measuring the amount of carbon dioxide emitted from soil samples to evaluate the fertility and health of the soil. Usually, CO2 sensors or gas analyzers are used. Microorganisms' respiration rate is a good indicator of soil biological activity and organic matter decomposition. The higher the rate, the more active microbial communities are.
Infiltration tests
Soil water infiltration rates can indicate soil structure, compaction, and porosity. Simple methods include the double-ring infiltrometer or the water infiltration rate test. Low rates are often a result of poor structure, high compaction, and smaller pore spaces.
Actions to improve your soil's quality
Good quality soil is crucial for healthy crop growth. Regenerative agricultural practices offer holistic approaches by prioritizing ecosystem restoration for resilient long-term food production.
No-till or reduced tillage
Conservation tillage minimizes soil disturbance to preserve its structure and organic matter content. It reduces erosion and promotes soil biodiversity and water retention.
Cover cropping
Planting cover crops—such as legumes, grasses, or blends of several species—between cash crops or during fallow seasons adds organic matter, suppresses weeds, and prevents soil erosion. This improves microbial diversity, nutrient cycling, soil structure, and water infiltration rates.
Crop rotation
Pest and disease cycles can be disrupted by gradually changing crops grown in a field. Since every crop needs different nutrients, it also enhances the health of the soil. Additionally, the many root structures can rebuild the structure and fertility of the soil.
Integrated livestock grazing
Managed rotational grazing can enhance soil fertility, control weeds and pests, and promote nutrient cycling. Livestock grazing contributes to soil organic matter deposition and nutrient recycling. It also diversifies farm income streams.
Agroforestry
The incorporation of shrubs or trees into agricultural landscapes can promote soil fertility, conserve biodiversity, and contribute to climate resilience. In addition to providing shade and lowering wind speed, trees also supply organic matter through root turnover and leaf litter. Additionally, microclimate conditions are enhanced by improving soil moisture retention and reducing evapotranspiration. Agroforestry also provides habitats for wildlife and mitigates the impacts of extreme weather. Trees can be used with crops or livestock to maximize ecosystem services and diversify farm income.
Alley cropping: Planting rows of shrubs or trees with adequate spacing alongside rows of annual crops or perennial forages.
Windbreaks: Single or multiple rows of shrubs or trees planted to protect crops, livestock, and soil from wind erosion and damage. These are planted perpendicular to the prevailing wind direction.
Silvopasture: Combining shrubs or trees with pasture or forage areas where livestock graze. This provides shade, reduces heat stress, and improves animal welfare. It offers shelter and additional forage resources as well.
Composting and organic amendments
Adding organic matter enhances soil structure, water retention, and nutrient availability. Compost, manure, cover crops, and crop residues can raise the soil's organic carbon content. It helps retain soil moisture and feeds beneficial soil microorganisms, essential for organic matter decomposition, nutrient cycling, and overall healthy soil. Composting organic waste can also help cut down on landfill waste.
Soil erosion management
Minimizing erosion is crucial to protecting soil health. Maintaining vegetative cover and reducing soil disturbance are key to preventing erosion and promoting water infiltration. Lowering sediment and nutrient runoff into water bodies can help manage nutrients and improve water quality.
There are several ways to manage erosion:
Contour farming: Planting crops along the land's contour lines, perpendicular to the slope. Crops can be cultivated using the natural contours of elevation lines. As the water flows through the terrain, runoff is slowed down.
Terracing: Creating level areas on steep slopes with earthen embankments or terraces. By capturing runoff water, it enables silt to settle before it reaches lower slopes or streams.
Grassed waterways: Vegetated channels or swales to control surface water runoff and shield fields from flooding. They should be placed in areas prone to erosion or natural drainage. Grass cover stabilizes the soil, prevents gully erosion, and improves water quality. These waterways can filter sediments and pollutants from runoff and provide a wildlife habitat.
Vegetative buffer strips: Vegetative areas are typically planted along field edges to serve as natural barriers. They can consist of grasses, legumes, native vegetation, trees, or a mix/combination of plant species. The strips can absorb nutrients, catch sediment, and slow down surface runoff. The roots retain the soil particles, preventing them from being washed away. The vegetation also improves water quality and supports wildlife.
Soil biology management
Low soil disturbance, high organic additions, and avoiding misuse of synthetic fertilizers and pesticides can all help to promote soil microbial ecosystems.
Drainage management
Soil drainage problems can be resolved by carefully leveling the area, installing drainage systems, and positioning tile drains. This is important to avoid waterlogging, lessen soil compaction, and promote root growth.
Nutrient management
In addition to ensuring crops receive enough nutrients, balanced fertilization reduces runoff and leaching. Regularly testing the soil is essential to ensure soil fertility and maintaining soil health for long-term crop production.
Water management
Using drip irrigation, collecting rainwater and conservational tilling helps water resource conservation. These practices also reduce runoff and erosion, improving soil moisture management. Especially in water-limited regions, efficient water use is critical for the maintenance of agricultural productivity and ecosystem health.
In short, healthy soil is essential for ecosystems and farming to coexist. Regenerative agricultural practices allow for the restoration and enhancement of soil fertility for long-term sustainability. It is important to regularly monitor soil health indicators to track soil quality over time and guide management decisions. Ultimately, good soil health enhances crop productivity, resilience, and sustainability.
Keep in mind that restoration takes time and requires patience. In optimal conditions with a mild climate, it takes more than 200 to 400 years for a single centimeter of topsoil to form!
Further reading
What is crop rotation and why it is good?
Zero Till Agriculture – A Brief History and Case Study
Tillage can sometimes help but usually harm soil and water conservation
