Kentucky State researchers take a longer look at biochar’s benefits for farmland

Third-year findings add to earlier results as the team studies how to keep soybean soil productive

FRANKFORT, Ky. — Food security depends on soil that keeps producing through many growing seasons. At Kentucky State University, researchers are returning to a soybean field year after year to learn whether biochar can help farmers protect it. Their latest study adds a third year of evidence to a question that takes time to answer.

Biochar is a charcoal-like material made by heating wood or other plant matter with very little oxygen. Farmers can mix it into soil in hopes of helping the ground retain water and nutrients and maintain the carbon that supports soil health. But they need field evidence to know what it can accomplish on their own land.

Srijana Kandel brought experience working directly with farmers to that question. Before joining Kentucky State’s Agronomy Lab as a master’s student, she served as an agricultural officer in Nepal, helping growers with crop production. She led the new study under the mentorship of Dr. Anuj Chiluwal, assistant professor of agronomy and the lab’s principal investigator.

Kentucky State reported the first two years of the research in June. Those findings appeared in Frontiers in Agronomy as “Response of acidic silt loam soil properties to biochar application under soybean cultivation.” In that analysis, led by Kentucky State graduate Binaya Baral, soil treated with biochar made from pine sawdust was less acidic after harvest and had more carbon than untreated soil. The team continued measuring to learn what a longer period would reveal.

For the new paper, “Medium term assessment of soil properties in a biochar amended Kentucky silty loam soil,” published in Discover Soil, Kandel and her colleagues collected soil before planting and after harvest in the third year. At Kentucky State’s Harold R. Benson Research and Demonstration Farm, they compared treated and untreated soybean plots, taking samples near the surface and farther down.

After harvest, the treated plots showed a small increase, about 3%, in a form of carbon associated with biological activity in the soil. Levels of manganese, a nutrient plants need in small amounts, also rose. Most other measures, including how much water the soil could hold, its acidity, and its levels of nutrients and total carbon, showed little difference between treated and untreated plots in this later analysis. The paper did not examine whether biochar affected the soybean harvest.

The earlier and later papers looked at soil at different times and depths. Together, they show why the team has kept gathering evidence: researchers need to learn whether encouraging early changes persist and whether they lead to benefits farmers can use.

This field had been used for hay production for decades. Its soil was already relatively fertile and stable when the experiment began, leaving less room for an obvious improvement. A field with poorer soil could respond differently. Kandel and her colleagues say more years of observation are needed to determine whether biochar helps maintain healthy soil before its condition declines.

Baral is a co-author of the new paper, along with fellow Kentucky State graduate Prakriti Paudel. Faculty co-authors are Dr. Pamela Obura, assistant professor of agroecology; Dr. Maheteme Gebremedhin, chair of the School of Agriculture and Natural Resources and associate professor of soil science; and Dr. Chiluwal, the paper’s corresponding author.

The research was supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture through an 1890 Capacity Building Grant, Award No. 2023-38821-39960, and Evans–Allen research funding, Accession No. 7004460.

Legal Disclaimer:

EIN Presswire provides this news content "as is" without warranty of any kind. We do not accept any responsibility or liability for the accuracy, content, images, videos, licenses, completeness, legality, or reliability of the information contained in this article. If you have any complaints or copyright issues related to this article, kindly contact the author above.