Next Article in Journal / Special Issue
Biochar Impacts on Soil Physical Properties and Greenhouse Gas Emissions
Previous Article in Journal / Special Issue
A Review of Biochar and Soil Nitrogen Dynamics
Article Menu

Export Article

Open AccessArticle
Agronomy 2013, 3(2), 294-312;

Characterization and Mineralization Rates of Low Temperature Peanut Hull and Pine Chip Biochars

The University of Georgia, Department of Crop and Soil Sciences, Miller Plant Sciences, Athens, GA 30602, USA
The University of Georgia, Department of Biological and Agricultural Engineering, Driftmier Engineering Center, Athens, GA 30602, USA
Author to whom correspondence should be addressed.
Received: 30 November 2012 / Revised: 23 January 2013 / Accepted: 7 April 2013 / Published: 16 April 2013
(This article belongs to the Special Issue Biochar as Option for Sustainable Resource Management)
Full-Text   |   PDF [620 KB, uploaded 16 April 2013]   |  


Biochar can potentially increase soil fertility and sequester carbon by incorporating nutrients and stable black carbon into the soil; however its effect on soil nitrogen (N) and carbon (C) processes is not well understood. A defined methodology to characterize biochar is necessary to predict how specific biochars will affect C and N mineralization. We amended a Tifton soil (Fine-loamy, siliceous, thermic Plinthic Kandiudults) with peanut hull (Arachis hypogaea; PH; 2.1% N) and pine chip (Pinus taeda; PC: 0.4% N) biochar at application rates of 1% and 2% (w/w) and performed a 136-day mineralization study. A companion 24-day mineralization study amended Tifton soil with PH and PC biochar at 2% and their respective feedstocks at equal C rates. Soil C mineralization rates were monitored periodically throughout each study and total N mineralization rates were also measured. In addition, we characterized each biochar using thermogravimetric analysis with mass spectrometer (TGA-MS), proximate analysis, Fourier transform infrared spectroscopy (FTIR), and total mineral analysis to identify biochar characteristics that might correlate with mineralization properties. Limited C (<2%) mineralized from both biochars, but mineralization rates of soil amended with PH biochar were higher than PC biochar. Carbon mineralization correlated well with estimated aliphatic content determined by TGA-MS but not with volatile content indicated by proximate analysis. Nitrogen was not mineralized from either biochar, indicating that plant-based biochar should not be considered a source of N for plant growth. The N in biochar may be contained in the stable aromatic structure of the biochar, as indicated by TGA-MS, and not available to soil microbes. View Full-Text
Keywords: biochar; soil; mineralization; characterization; carbon; nitrogen biochar; soil; mineralization; characterization; carbon; nitrogen

Figure 1

This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Share & Cite This Article

MDPI and ACS Style

Harris, K.; Gaskin, J.; Cabrera, M.; Miller, W.; Das, K. Characterization and Mineralization Rates of Low Temperature Peanut Hull and Pine Chip Biochars. Agronomy 2013, 3, 294-312.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Agronomy EISSN 2073-4395 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top