Land Application of Gasification Biochar.

Biochar, a co-product of thermochemical bioenergy production, may be a valuable soil amendment, but little is known about its effects on soil fertility and subsequent plant productivity. The objectives of this research were to determine the effects of biochar application on forage sorghum production, N response, and soil fertility properties. Field studies were carried out at St. John, KS and Butler, MO with a split-plot experimental design.  Whole plot treatments were biochar (37 Mg/ha), fertilizer (lime, P, and K addition), and control (no lime, P, or K addition).  Sub-plot treatments were N applied at 0, 60, 120, and 180 kg N/ha.  Biochar treatments did not affect sorghum yield or sorghum response to N; however yield was severely limited by drought at one location, which confounded results.  Biochar significantly increased pH, total C, total N, available P, and available K in soils. Phosphorus and K concentrations in plant tissue were also increased as a result of biochar application.  Biochar may be an effective means of recycling nutrients back to soils in bioenergy production systems. Additional years of research are needed to determine effects on crop growth and long-term soil fertility properties.