How to differentiate between poor and healthy soil?
According to the US Department of Agriculture, soil health, or soil quality, is defined as the capacity of a particular type of soil to function within natural or managed ecosystem boundaries to
- maintain or improve water and air quality
- sustain plant and animal productivity
- support human health and habitation
Early Concept of Field Rotation
As early as 6000 BC, farmers had the knowledge about the concept of alternating crops to enhance the soil. In the Bible, chapter 25 of the Book of Leviticus directs the Israelites to observe a “Sabbath of the Land.” Every seventh year, they were forbidden from tilling, pruning, or even controlling insects. During the middle ages, Europeans adopted two, three, and ultimately four field rotation of crops to maintain soil health to increase crop yields.
The common characteristic of these methods was the idea that when given the right opportunity to rest and regenerate, soil would have the ability to maintain its quality over longer periods.
The Advent of Industrial Farming
This belief started to change only after the 20th century and as a result of the growth of large-scale, industrial farming. It was the result of the notion that additional chemicals and fertilizers can be used to manage soil health. Similar to what is practiced in America, industrial farming transformed the middle states into what was commonly denoted as the “breadbaskets of the world.”
The difficulties posed by artificial chemical fertilizers has led a new generation of farmers to resort to the older concepts of soil health. The advantages are evident. Healthy soil requires less watering and little or no fertilizer. It is also more drought resistant.
Determining Soil Health Using Haney Test
The challenge for farmers, then, is to know what constitutes healthy soil? Although it is straightforward to classify soil as either being healthy or unhealthy, it is considerably hard to ascertain whether soil is 30% versus 70% healthy. Objective tests such as these are required to reduce the inputs required to bring partially healthy soil back to 100% healthy soil.
Several tests and checklists exist for healthy soil; however, one of the most intriguing ones is the Haney Test, named after Dr Rick Haney, a Soil Scientist at the Grassland Soil and Water Research Laboratory for the USDA-ARS, at the 2015 Western Nutrient Management Conference.
The test was based on the observation that the drying and rewetting of soil activates a burst of respiration. Such a microbial burst is quantified by evaluating for carbon dioxide (CO2) after rewetting a dried, ground soil sample. Carbon dioxide evolution, along with other laboratory measurements, is employed in an equation to assess the Soil Health Score and evaluate the amount of additional fertilizer needed to bring the soil up to perfect health.
Sadly, although the Haney Test works well in the laboratory, it is still challenging to perform using basic tools in the field. Even in laboratories, there still exists a question of standard results as a result of variables such as soil wetness, objective versus subjective test results analysis, test duration, and more.
CO2Meter’s CO2 Sensor for Performing Soil Health Test
As soon as an objective test standard is obtained, the subsequent challenge will be to formulate a low-cost soil health test that can be used by farmers in the field. For this purpose, CO2Meter has been working with Dr Haney to determine the CO2 sensor that offers the ideal price/performance for his apparatus.
Despite the fact that the Haney Test is still in the early development stages, as time goes on, it could become an innovative tool in the fight to create the healthiest soil to enhance crop growth. CO2Meter is proud to collaborate with Dr Haney and will keep the customers posted on his results.
This information has been sourced, reviewed and adapted from materials provided by CO2Meter.
For more information on this source, please visit CO2Meter.