Ascension Soil Company - bringing soils to life

Biochar Articles - Journal of Environmental Quality Articles

Biochar and the Nitrogen Cycle: Introduction

Tim J. Clough and Leo M. Condron 

Abstract

Nitrogen (N) is an essential nutrient, and research to date shows that biochar potentially has the ability to manipulate the rates of N cycling in soil systems by influencing nitrification rates and adsorption of ammonia and increasing NH₄⁺ storage by enhancing cation exchange capacity in soils. Its influence on these processes may have further implications in terms of reducing gaseous N losses such as N₂O and nitrate leaching. However, further detailed research is required to fully understand the transformation mechanisms and fate of N when associated with biochar treated soils. The three research papers that comprise this special collection of papers on biochar and the nitrogen cycle focus on biochar’s diverse ability to influence N cycling processes. These papers show for the first time (i) how microbial nitrification communities and function differ with exposure to biochar, (ii) how the length of time the soil has been in contact with biochar influences N transformation and how this can vary with soil type, and (iii) how composting of organic materials with biochar can reduce N losses and enhance the nutrient status of the composted product. Considerable knowledge gaps still exist in terms of understanding the precise mechanisms through which biochar influences soil N transformations, and how biochar affects both plant and microbial N supply. The general direction that research on biochar should focus on with respect to the N cycle is the effect(s) that biochar has on N transformation in soils, both chemical and biological mechanisms, and the fate of N applied to biochar treated soils. This research needs to be performed at both field plot and microbial scales.

https://www.agronomy.org/publications/jeq/abstracts/39/4/1218

Influence of Biochars on Nitrous Oxide Emission and Nitrogen Leaching from Two Contrasting Soils

Bhupinder Pal Singh, Blake J. Hatton, Balwant Singh, Annette L. Cowie and Amrit Kathuria

Abstract

The influence of biochar on nitrogen (N) transformation processes in soil is not fully understood. This study assessed the influence of four biochars (wood and poultry manure biochars synthesized at 400°C, nonactivated, and at 550°C, activated, abbreviated as: W400, PM400, W550, PM550, respectively) on nitrous oxide (N₂O) emission and N leaching from an Alfisol and a Vertisol. Repacked soil columns were subjected to three wetting–drying (W–D) cycles to achieve a range of water-filled pore space (WFPS) over a 5-mo period. During the first two W–D cycles, W400 and W550 had inconsistent effects on N₂O emissions and the soils amended with PM400 produced higher N₂O emissions relative to the control. The initially greater N₂O emission from the PM400 soils was ascribed to its higher labile intrinsic N content than the other biochars. During the third W–D cycle, all biochar treatments consistently decreased N₂O emissions, cumulatively by 14 to 73% from the Alfisol and by 23 to 52% from the Vertisol, relative to their controls. In the first leaching event, higher nitrate leaching occurred from the PM400-amended soils compared with the other treatments. In the second event, the leaching of ammonium was reduced by 55 to 93% from the W550- and PM550-Alfisol and Vertisol, and by 87 to 94% from the W400- and PM400-Vertisol only (cf. control). We propose that the increased effectiveness of biochars in reducing N₂O emissions and ammonium leaching over time was due to increased sorption capacity of biochars through oxidative reactions on the biochar surfaces with ageing.

https://www.agronomy.org/publications/jeq/abstracts/39/4/1224

Reducing Nitrogen Loss during Poultry Litter Composting Using Biochar

Christoph Steiner, K.C. Das , Nathan Melear  and Donald Lakly 

Abstract

Poultry litter (PL) is a potentially underused fertilizer because it contains appreciable amounts of N, P, K, and micronutrients. However, treatments like composting to reduce potential pathogens, weed seeds, and odor often result in high losses of N through NH₃ volatilization. Biochar (BC) has been shown to act as an absorber of NH₃ and water-soluble NH₄⁺ and might therefore reduce losses of N during composting of manure. We produced three PL compost mixtures that consisted of PL without added BC (BC0), PL + 5% BC (BC5), and PL + 20% BC (BC20). The BC was produced from pine chips and used without further modifications. Three replicates of each treatment were placed in nine bioreactors to undergo composting for 42 d. The entire composting experiment was repeated three times in a complete-block design. Moisture content, temperature, pH, mass loss, gas (NH₃, CO₂, H₂S) emissions, C, and nutrient contents were measured periodically throughout the experiments. Results showed no difference in PL mass loss with BC addition. Moisture content decreased, pH increased significantly, and peak CO₂ and temperatures were significantly higher with BC20 compared with BC0. These results indicate a faster decomposition of PL if amended with BC. Ammonia concentrations in the emissions were lower by up to 64% if PL was mixed with BC (BC20), and total N losses were reduced by up to 52%. Biochar might be an ideal bulking agent for composting N-rich materials

https://www.agronomy.org/publications/jeq/abstracts/39/4/1236

Biochar in Reclamation

I recently participated in the US Biochar Conference held in Ames Iowa - the agenda and presentations can be found at http://www.biorenew.iastate.edu/events/biochar2010/conference-agenda/agenda-overview.html

I participated in the first session of the conference on the Assessment of Biochar’s Benefits for the United States of America, and gave a paper titled “The Role of Biochar in the Carbon Dynamics in Drastically Disturbed Soils” (for a copy, email andrewharley@ascensionsoil.com).  The above table was adapted from Shrestha and Lal (2006) Ecosystem carbon budgeting and soil carbon sequestration in reclaimed mine soil Environment International, 32, 781-796 and shows the many possibilities that exist for biochar in the reclamation space.

Organic matter is king when it comes to reclamation, controlling soil chemical and physical including water holding capacity and soil structure, improving infiltration and reducing erosion.  The combined recalcitrant nature and surface reactivity of biochar make it a promising amendment in areas where moisture is limited and where soil surface characteristics reduce infiltration.  By increasing organic carbon in these environments, the ability to increase other ecosystem services including improved biodiversity and water quality.

Additionally, the role of “designer biochar” for dealing with specific toxicity issues (acid, metals) has great potential and provide an opportunity to build buffering capacity on the soil while developing the carbon cycle, and this is the current focus of my research interest.

While all this sounds good in theory, there is plenty of research required to understand how interacting processes are expressed in various mineralogical, geochemical and hydrologic settings for the optimal application of biochar in disturbed land reclamation.  I am developing research projects in the Rocky Mountains, looking for the nexus between the use of either mountain pine beetle waste or woody invasives such as tamarisk or pinyon/juniper and reclamation of either abandoned mine lands or active mines in reclamation mode.

I am developing collaborations with researchers to set up bench-scale, glasshouse scale and field scale trials. I am looking for additional collaborations and if you have any interest in joining in please email me at andrewharley@ascensionsoil.com.

Welcome to my blog - ASC explained

Ascension Soil Company was borne out my academic and personal research into methods, techniques and philosophies that helped bring life back to infertile and essentially sterile soils.

The journey began on a glorious spring afternoon in southwest Colorado in 1996.  I was taking a sabbatical from environmental consulting to fulfill one of my lifes ambitions of learning to ski (90 ski days in Telluride during a record ski year).  I was waiting for the Durango & Silverton Narrow Guage Railroad (http://www.durangotrain.com/) to pull into Durango.  With an hour to kill, I lazily strolled into a bookstore.  Little did I know that I this act would change the course of my life, for literally jumping off the shelf was Peter Tompkins and Christopher Bird’s alternative remedies for restoring soils “Secrets of the Soil”.  With an undergrad in earth sciences, including soils, I was immediately intrigued by one chapter in particular - Chapter 15 Dust for Life - which went to to describe the process of remineralization: adding ground rock to soils to improve soil quality and nutrition (more can be found at www.remineralize.org). 

With a new bride in tow, I ended up studying with the great Bob Gilkes at the Univeristy of Western Australia producing a thesis on The Evaluation and Improvement of Silicate Mineral Fertilisers.  The abstract can be found at www.ascensionsoil.com/research and please email me for a copy (andrewharley@ascensionsoil.com). 

In addition to remineralization, I have studied a diverse area of soil restoration, including:

• Dr Daniel Hillel’s work on soil and water science;
• Dr Rattan Lal’s work on soil carbon, especailly in mine reclamation (https://pro.osu.edu/profiles/lal.1/);
• water management and the work of P.A. Yeomans (Keyline) and Vicktor Schauberger (Natural Water Management);
• organic matter management and the work of Alan Savory (Holistic Resource Management);
• permaculture sytems and the work of Bill Mollison;
• biodynamics and the work of Rudolf Steiner;
• Nutritional minerals and the work of William Albrecht, Andre Voisin and Joel Wallach; and
• biochar and the work of Johannes Lehmann et. al. (http://www.css.cornell.edu/faculty/lehmann/index.html)

My current focus is the use of Biochar for the reclamation of drastically disturbed lands, especially in the arid and semi-arid American West.  This will be the focus of most of my blogs as I move forward in this direction.

This blog is intended as a clearing house for a range of resources that I have accumulated over the years.