At the recent Summit on Canadian Soil Health in Guelph, Ontario, Don Lobb, a farmer and conservation leader in Canada emphasized the importance of proper management of soils:
“No civilization has ever survived the consequences of exploitative agriculture. As soil was degraded, the survivors moved on to new frontiers. Today, there are no new frontiers. We must take advantage of the one opportunity left- intensive, scientifically sound, responsible soil management that accommodates a healthy soil biota community”.
The message is one that has been increasingly emphasized at agricultural conferences and workshops over the past few years: healthy soils are essential for maintaining food production and a healthy environment, now and into the future. More and more, the agricultural sector is buying in to this line of thinking. Today’s farmers are eager to learn more about, and implement strategies to improve soil health – both for their immediate needs and for future generations.
Why is soil health so important? One definition of soil health is: the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans. This definition speaks to the importance of managing soils so they are sustainable over the long term. Healthy soils foster large communities of microorganisms, support healthy crop growth, sequester carbon, manage water and filter contaminants – it is the building block for our existence on this planet. Another increasingly relevant and important benefit of healthy soils is improved resilience to unpredictable and severe weather conditions due to their ability to retain soil moisture during drought conditions and to allow for infiltration during significant rainfall events.
One of the most important components of healthy soils is organic matter content. Think of organic matter as the glue that promotes soil structure. It is food for microorganisms, a source of slow release nutrients for crop growth and it is the sponge that provides the capacity to retain water. Synthetic fertilizers can certainly provide for the chemical needs of the soil, but they do not improve the biological or physical components. Adding organic matter improves the chemical, physical and biological properties of soil, improving its function and long term sustainability. These are all factors that are driving demand for the various organic amendments available (biosolids, biosolids derived products (such as LysteGro®), digestate, compost, and several others).
As the agricultural community continues to expand its focus on soil health, the benefits of biosolids and other organic amendments become more understood and the demand for these materials increases. This is especially true for farmers that do not have access to adequate sources of manure. In these cases, biosolids and other organic amendments are an excellent tool to add organic matter and improve soil health. Other beneficial soil management practices, such as minimum-tillage and the use of cover crops provide synergies when used in conjunction with organic amendments.
As an example, the vast majority of LysteGro customers are using these beneficial management practices, often in conjunction with the product (for example, injecting LysteGro prior to cover crop planting or injecting into a living cover crop). As Christine Brown, Nutrient Management Field Crop Lead with the Ontario Ministry of Agriculture Food and Rural Affairs (OMAFRA), says “when using an organic amendment with a cover crop, it’s 1+1 = 4”. By using cover crops in conjunction with organic amendments, the plant is able to use the nutrients provided, which will in turn retain a percentage of those nutrients for the next growing season, while also enhancing the growth and beneficial effects of the cover crop.
A couple of challenges in promoting the uptake of practices that will benefit soil health is the amount of time required to show benefits of soil health (often requiring several years of using best management practices aimed at soil health improvement) – and how to quantify it. Soil health is a difficult thing to measure. It is like going to the doctor and asking the broad question “Am I healthy?” There are many different components of health. For example, you may have a healthy heart, but be experiencing stomach issues – so do you define this as “healthy” or “not healthy”? Soil scientists have been working for many years to develop tests that comprehensively assess soil health. There are several assessment tools that take into account different health indicators and assign a score for each indicator. Overall soil health is assessed based on the combination of scores in each area.
An example of a comprehensive Soil Health Test is the Cornell Soil Health Test, developed by scientists at Cornell University. The test analyzes for chemical (pH, nutrients), biological (organic matter, respiration, plant root health) and physical (texture, aggregate stability, water capacity) characteristics that are all important components of soil health. The scoring for each of the parameters is combined to provide an overall score, which can be compared in a field over the medium term, in order to assess how changes in management affect soil health over time. There are several other soil health tests available (such as the Solvita and Haney tests), all with varying ranges of parameters and cost.
Despite the difficulty in measuring soil health, the benefits of incorporating biosolids and/or other organic amendments as part of today’s approach to best practice are obvious to those who have made it a focus. From an environmental perspective this is a vital component of the growing trend toward resource recovery – and it is a great way to jump-start the process of building healthy, more sustainable soil.
Authored by Samantha Halloran, Project Coordinator, Lystek