According to the NRCS, soil health is defined as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans.” From a production agriculture point of view, soil health is important in order to maintain yields. However, soil health also plays a very important role in the ability of a soil to sustain life and the health characteristics that successfully support that life for years to come.
Soil consists of 4 parts: mineral solids, water, air, and soil organic matter. These minerals and nutrients are made available through mineralization or decomposition, which is made possible by the living organisms that are present in the soil. The movement of air and water through soil is dependent upon pores and pathways, many of which are created by the movement of organisms through the soil. Soil organic matter is itself the living, dead, and decomposed organisms.
Being that soil health plays such an important role in life and agriculture, Dairy One recognizes the importance of measuring soil health in order to better manage it and your operation. Agro-One agronomy services, a subsidiary of Dairy One, offers a Soil Health Report which includes 3 tests related to soil health: Solvita CO2 Burst, Solvita SLAN, and Solvita VAST. These tests measure the respiration of soil microorganisms, plant available nitrogen, and soil structure or “tilth”.
Solvita CO2 Burst
Decomposition is a process that is found throughout the topic of organic matter. Organic matter makes up 1-6% of soil and is made up of living organisms, fresh residues (dead), and well-decomposed residues (very dead). Living organisms consist of bacteria, viruses, fungi, protozoa, insects, and larger animals and make up about 15% of organic matter. In my mind, the living organisms are catalysts to the decomposition process. It is the respiration of these living organisms that is measured by the Solvita CO2 Burst test.
A chemical measurement of soil health would be the amount of plant available nitrogen in the soil. The Solvita SLAN test measures the organic compounds of nitrogen, which are mineralized and made available to plants. Mineralization is the process in which living organisms, such as bacteria and fungi, breakdown organic elements in the soil into their mineral, or inorganic, forms. It is through this process that proteins in the soil are transformed into plant available forms of nitrogen, such as ammonium and nitrates.
One of the words used to describe soil health from a physical stand point is soil structure or “tilth”. Soil tilth takes into consideration the size of soil particles and the size and variety of the space, or pores, between particles. These pores are what allow for the movement of air, water, roots, and other living organisms in the soil. If a soil has good tilth, it is spongy, porous and aerated, making it favorable for plant growth. Tilth determines a soil’s water-holding capacity, infiltration of rainfall, air movement, rooting depth, and soil productivity. The quality of a soil’s tilth is measured using the Solvita VAST test.
The goal of almost every farmer, or back yard gardener, would be to have healthy soil. Ideally, healthy soil would require minimal if any artificial fertilizers, irrigation, pesticides and machinery. Many of these artificial practices can be detrimental to topsoil health, as well as costly to farmers. The majority of organic matter is found in top soil and as it increases, so too do crop yields. Unfortunately, it is the top soil that is most damaged by erosion, wind, or even salinity in arid climates. Management techniques such as reduced tillage, cover cropping, crop rotation, and the application of manure are ways that farmers can reduce the loss of, and replenish the valuable soil organic matter in their soils.
For more information on the Soil Health Report or other types of soil analysis, contact our Agro-One and Forage Lab customer support team at 800.344.2697, ext 2172 or click here.