The effect of charcoal on maize yield

Data from a study published in the European Journal of Agronomy revealed that adding biochar to farm soil in Belgium significantly increased maize/corn (Zea mays) yield. The researchers said that this was because the presence of charcoal helped increase available water content in the soil. The findings implied that charcoal effect on maize yield was at its highest during Belgium’s driest growing season. Unlike controls, the charcoal-enriched soils had higher available water content.

• For the study, scientists analyzed above-ground silage maize yield in soils under historical charcoal kilns (or black spots, with less than 150 years of enrichment) and adjacent soils in southern Belgium for three consecutive years (2014 to 2016).
• Data showed that the average maize yield in well-fertilized farmable soil was 23 percent higher in the aforementioned black spots compared to the adjacent soils. Meanwhile, the charcoal-C concentration was, on average, 63 percent of total soil organic carbon (SOC) in the black spots.
• Maize yield increase went down following average rainfall during the growing season. Water retention curves of both soil types revealed available water content that was 11 percent higher in soils under black spots.
• The delta C 13 analysis of maize leaves at final harvest, which was accomplished during one season, implied that there was lower water stress for plants that were cultivated on black spots.
• Nutrient concentrations in maize leaves remained the same despite the addition of charcoal. However, adding biochar had noteworthy positive effects on soil cation exchange capacity (CEC). Concentrations of available calcium (Ca) and magnesium (Mg) were also detected in the soil.

The findings imply that adding historical charcoal to fertile and temperate soils can help increase maize yield, however; it’s possible that this occurs due to the soil’s physical effects instead of its nutritional effects.

Visit Harvest.news to learn more about the benefits of adding biochar to soil and how it can boost maize yield.

Journal Reference: 

Kerré B, Willaert B, Cornelis Y, Smolders E. LONG-TERM PRESENCE OF CHARCOAL INCREASES MAIZE YIELD IN BELGIUM DUE TO INCREASED SOIL WATER AVAILABILITY. EUROPEAN JOURNAL OF AGRONOMY. 2017;91:10–15. DOI: 10.1016/j.eja.2017.09.003