Universal Test To Rule All Soil Types

The quality of plant life depends on the soil. Soil is rich in nutrients and also contains microbes. The microbes present in the soil helps plant synthesize food in the presence of sunlight. But we can expect much more from the soil.
The factor that affects the soil quality the most is fertilizer. No doubt, fertilizers boost crop yield. But it also has some disadvantages. For instance,
Unabsorbed fertilizers can move with rainwater. Ultimately these fertilizers will be part of oceans, lakes, and streams. As a result, there will be a dead zone in these water bodies due to excess phosphorous and nitrogen.
Now the question is, what is a dead zone?
It is an area with low oxygen concentration due to rotting algae. This alga grows in water due to excess nutrients that plants don’t utilize and now are in the water.
However, this problem could be solved only if the farmers know the nutrient content of the soil.
Here’s how this information could be helpful for the farmers:
• It will help farmers to apply only the required amount of nutrients.
• It gives information about the risk of nutrient loss.
So, you can get all this information with the help of different tests. But you can’t get every type of information with a single test. Instead, there are different tests to get a different type of information.
Rishi Prasad is the lead scientist of this research project at Auburn University’s Crop, Soil, and Environmental Sciences Department. Under this project, researchers tried to find the universal soil test for all soil types. This research is published in Agrosystems, Geosciences and Environmental journal.
Why is there a need for a universal soil test?
According to Prasad, planet earth has different types of soil. Each type of soil varies in mineralogical and chemical properties. Therefore, different soil tests are used according to regional needs. Moreover, he mentioned that universal soil tests could perform better than region-specific soil tests.
It would be much easier to compare soil of different areas with a single and practical test.
The most commonly used soil tests are Lancaster, Mehlich 3, and Mehlich 1. These tests were named after the scientists who used and developed them. For instance, Mehlich 1 was used for some soil types in Alabama. At the same type, Lancaster was used for other soil types.
On the other hand, Mehlich 3 was not tested in Alabama.
Methodology of research
• In the first step, they collected samples of five different types of soils from the Alabama region.
• In the second step, they use all three tests to test the soil samples’ phosphorous levels.
• In the third step, they determine the water-soluble phosphorus. It is vital to measure the water-soluble phosphorous because it is a readily available form of phosphorus. At the same time, this form of phosphorous can also runoff easily with rainwater.
Findings of the research
Research findings indicate that
• Mehlich 3 and Lancaster extract 1.5 times the phosphorus content than the Mehlich 1. The performance of Mehlich 3 doesn’t match with any of the other tests.
• Mehlich 3 helps in the most accurate measurement of water-soluble phosphorus.
Importance of estimating the water-soluble phosphorus
It is crucial to determine the water-soluble phosphorus, specifically in Alabama. One reason behind this importance is the production of a large amount of manure in the state. Farmers use this manure as fertilizer on farms.
Using manure as fertilizer help in recycling nutrients. According to Prasad, large exposure of farms to manure increases the phosphorous content of the soil. Therefore, it is crucial to find a soil test that accurately determines phosphorous loss.
And guess what Mehlich 3 wins the game. However, the full implementation of Mehlich 3 across Alabama needs more research. Prasad says that extensive field calibration and verification studies are essential to recommend agronomic fertilizer within a specific soil region. However, it takes time and money for a calibration study.
Importance of creating standardized test
The development of standardized tests could have significant benefits. For instance, it helps farmers
• Protect the local environment
• Grow food more efficiently.
Alabama Agricultural Experiment Station and the Hatch Program of the National Institute of Food and Agriculture, USDA, USDA ARS cooperative agreement (Grant ID G00012671), and the Alabama commodity organization, Alabama Soil & Water Conservation Committee (Grant ID G00011611) support this project.