There are many different factors which contribute towards maintaining healthy soil - it being the basis for a productive, high yielding sward.
Why Soil Maintenance is Important
Not only can healthy, nutritional soil influence populations and species of microorganisms, but it can also control nutrient availability. Healthy soil helps to breakdown organic matter and release key nutrients into the plant establishment. The organic matter provides exchange sites, preventing positively charged nutrients from being lost through leaching.
Other species maintain soil structure, such as earthworms, by creating channels and aiding air movement which is complementary to nitrogen fixation. Small species like millipedes, beetles, and fly larvae, provide a good source for larger beneficial predators. This in turn can control pest cycles within the sward and soil.
What Role Does pH Have in Soil Maintenance?
The pH of the soil influences the level of activity and species present within the soil. For example, legumes are accustomed to a pH closer to neutral in order to ensure the enzymes and microorganisms responsible for nitrogen fixation are working efficiently.
At a low pH, the number of cation exchange sites decrease, and more nutrients are leached from the soil.
The correct pH maintains a healthy fungi population, which in turn maintains a consistent supply of elements to the plant. For example, specific species of fungi work with plant roots to supply the plant with phosphorous, helping to promote root growth.
How Can Healthy Soil Impact Plant Growth?
Healthy soils contain a wide number of both species and predators. However, they also contain parasites and pathogens which are responsible for supressing the number of pests present in swards. For example, beetles target slugs and prevent weed establishment by consuming the seeds.
The spaces in between soil aggregates impacts air and water flow throughout the soil. While big spaces allow the water to enter the soil with ease and aid air movement. Smaller spaces contain water and air pockets, both being necessary for maximum plant growth.
What Is the Importance of Maintaining the Sward?
Keeping swards healthy can help maintain their longevity, the area withstanding natural occurrences such as adverse weather conditions, pests, and out competing weeds.
This translates to a consistent, high quality forage which feeds well, resulting in optimum animal health and production of beef, lamb, or milk.
What Are the Requirements of Soil and Sward?
Tillage is required to stimulate the activity of microorganisms in the soil, adding air and breaking up pockets of organic matter for digestion.
To prevent any deficiencies, fertilisers and organic matter are required to feed soil-dwelling species and to ensure nutrient levels are replenished. However, regular soil sampling can provide the correct pH and nutrient levels, allowing for targeted fertiliser application.
What Are the Impacts of Improper Sward Management?
The appropriate management of soil is largely dependent on the soil type, weather conditions, and location. Poorly maintained soil can have many environmental impacts, including nutrient leaching and denitrification from waterlogged soils.
However, soil trafficability is important when preventing compaction. When land is travelled on at the incorrect time of year or excessively during wet weather, soil can become compacted, leading to waterlogging and lack of airflow.
Due to this, a reduction in the pH of the soil can occur. Along with the topsoil being impenetrable by plant roots, the compacted soil can stunt plant growth and reduce yields.
On the other hand, excessive management can disturb the topsoil and bury organic matter and microorganisms which are responsible for keeping soil healthy. Through over management, the soil structure is therefore damaged.
The application of organic matter and fertiliser should match the offtakes from the crop and the losses from soil. While excessive application can lead to acidification of soils, the inadequate application can lead to swards with deficiencies in certain nutrients.