Evaluation of Biochar on Microbial N-cycling Populations: Biochars success as a soil conditioner can also lead to changes in the soil's microbial population. Whether these changes are beneficial or harmful is unknown. We recently concluded a six month study that looked at a switchgrass-derived biochar used to condition an eroded soil. Genes involved in nitrogen-cycling were all increased and correlated to the amount of biochar added. This indicates that switchgrass-derived biochar is beneficial to organisms involved in nitrogen cycling. Resources:
Designer Biochar Can Affect Specific Soil Properties:The concept of designer biochar was introduced by Novak et al. in 2008 and developed in a cooperative research project. The concept has been used by us and others to produce or design biochars that have properties tailored for particular uses such as amelioration of specific soil problems in our southeastern Coastal Plains. Different feedstocks and pyrolysis temperatures produce different carbon structural characteristics in biochars that affect their properties and their impact on soils.
Biochar Soil Amendment: Southeastern US Coastal Plain soils have low fertility because of their sandy texture, low pH, and low organic carbon (C) content. A Coastal soil was amended with pecan shell-based biochars that had high pH and highly stable C structures and were incubated for 67 days. Biochar amendment increased soil pH, C, Ca, and K contents. Amended soil leachate contained less P than the control which could improve ground and surface water quality. In a related study, biochar amendments made from several different feed stocks also improved the soil’s ability to hold water for plant growth, which should reduce crop water stress and increase productivity.
Corn Residue for Bioenergy: In a 5-yr cooperative study by the US Department of Energy (DOE), South Dakota State University, and ARS Florence, various amounts of corn plant residue are being removed from research plots for bioenergy production. The amount removed must be balanced with the amount remaining to maintain soil fertility/productivity. Preliminary results from soil and plant samples were uploaded to a central file maintained by DOE at Oak Ridge National Labs.
Long-term Conservation Tillage Can Rebuild Soil Organic Matter Levels in Sandy Soils: Conservation tillage management resulted in an additional 7600 pounds of organic matter per acre in the top 5 cm (2 in) of soil compared to conventional tillage management. Increased soil organic matter not only sequesters carbon, but it can also reduce runoff and erosion and improve water and nutrient retention for plant growth. Resources: