Types

Spreadsheet for Calculating Basic "New Terra Preta" Economics
Kevin Chisholm, May 13, 2008

This Spreadsheet should be helpful in getting a perspective on charcoal additions, to make a "New Terra Preta Soil.

Knowing soil density, the density of "loose charcoal" as it will be applied to the soil, the density of crushed charcoal, the depth to which the charcoal will be tilled in, and a proposed weight addition per square meter, we can then calculate the average depth of charcoal on the surface of the ground after spreading, and the weight percentage of charcoal that will exist, after the charcoal is tilled in to the desired depth.

1: If we know the cost of Charcoal: We can then calculate the cost per square meter for the charcoal, and the increased value of yield and other benefits that would be required for the charcoal addition to have the desired "Simple Payout Period."

2: If we know the value of the increase in yield and other benefits: We can then calculate the maximum permissible cost of the charcoal and its application cost per square meter, and the maximum we can afford to pay to attain our desired "Simple Payout Period."

This approach assumes that the charcoal addition simply allows the soil system to attain a higher potential, EITHER giving a Higher yield with the same level of nutrient additions and attention, OR the SAME yield, with a lower level level of nutrient additions and attention. Only the difference in the value of yield and attention is credited toward paying for the charcoal additions.

Note also that the charcoal additions are felt to provide nutrient retention, soil microbe habitat, and moisture retention advantages to the soil. If the soil was deficient in one or more of these requirements, then charcoal additions could be expected to be beneficial. On the other hand, if the soil was NOT deficient in these properties, then one would NOT expect a financial benefit to justify the cost of the charcoal additions.

Kevin Chisholm

Agronomic values of greenwaste biochar as a soil amendment
K. Y. Chan, L. Van Zwieten, I. Meszaros, A. Downie,and S. Joseph
Australian Journal of Soil Research 45(8) 629–634, December 2007

Abstract

A pot trial was carried out to investigate the effect of biochar produced from greenwaste by pyrolysis on the yield of radish (Raphanus sativus var. Long Scarlet) and the soil quality of an Alfisol. Three rates of biochar (10, 50 and 100 t/ha) with and without additional nitrogen application (100 kg N/ha) were investigated. The soil used in the pot trial was a hardsetting Alfisol (Chromosol) (0–0.1 m) with a long history of cropping. In the absence of N fertiliser, application of biochar to the soil did not increase radish yield even at the highest rate of 100 t/ha. However, a significant biochar × nitrogen fertiliser interaction was observed, in that higher yield increases were observed with increasing rates of biochar application in the presence of N fertiliser, highlighting the role of biochar in improving N fertiliser use efficiency of the plant. For example, additional increase in DM of radish in the presence of N fertiliser varied from 95% in the nil biochar control to 266% in the 100 t/ha biochar-amended soils. A slight but significant reduction in dry matter production of radish was observed when biochar was applied at 10 t/ha but the cause is unclear and requires further investigation.

Significant changes in soil quality including increases in pH, organic carbon, and exchangeable cations as well as reduction in tensile strength were observed at higher rates of biochar application (>50 t/ha). Particularly interesting are the improvements in soil physical properties of this hardsetting soil in terms of reduction in tensile strength and increases in field capacity.

Keywords: charcoal, char, agrichar, soil strength, soil carbon sequestration, hardsetting soil, slow pyrolysis.
Australian Journal of Soil Research 45(8) 629–634
Submitted: 27 July 2007 Accepted: 2 November 2007 Published: 7 December 2007
Full text DOI: 10.1071/SR07109

See also:Assessing agronomic values of chars to an Australian hardsetting soil presentation to the International Agrichar Initiative conference, Australia, 2007.

Terra Preta Magic Soil of the Lost Amazon
Allan Balliett, February 2007 as presented in TERRA, The Earth Renewal and Restoration Alliance

Nicely presented and illustrated version of Baillet's review by David Yarrow, webmaster.

Charcoal from Comets, Asteroids and Wildfires
Tom Miles, May 28, 2007

There is speculation that pockets of charcoal that resulted in enriched soil came variously from comets and asteroids and resulting wildfires, as well as intentional burning. The latest comet event has been reported as 12,900 years ago in North America. See Science Daily:
Did A Comet Hit Great Lakes Region, Fragment Human Populations, 12,900 Years Ago? May 23, 2007

and National Geographic News:
Comet Wiped Out Early North American Culture, Animals, Study Says May 23,2007

Potential extraterrestrial causes of terra preta formation are discussed in the literature from Cornell University and elsewhere. It has also been debated on the Hypography Science Forum.

The Terra Preta Phenomenon
Ray O’Grady and Rod Rush, DesertSmart Technologies, WA
‘Managing the Carbon Cycle’ Katanning Workshop 21-22 March 2007 www.amazingcarbon.com

Abstract

Dynamics of Soil Nutrients in the Rooting Zone with Reference to the Mechanisms of Nutrient Supply in Soil.
Junta Yanai1, Takashi Kosaki2, and Hidekazu Yamada1. (1) Kyoto Prefectural Univ, Shimogamo Hangi-cho 1-5, Sakyo, Kyoto, 606-8522, Japan, (2) Kyoto Univ, Sakyo-ku, Kyoto, 606-8502, Japan
18th World Congress of Soil Science, July 9-15, 2006, Philadelphia, PA, USA

Terra Preta Magic Soil of the Lost Amazon
Allan Balliett, in Acres USA, February 2007

Long term Effects of manure, charcoal and mineral fertilization on crop production and fertility on a highly weathered Central Amazonian upland soil January 2007
Christoph Steiner · Wenceslau G. Teixeira · Johannes Lehmann ·Thomas Nehls · Jeferson Luis Vasconcelos de Macêdo · Winfried E. H. Blum · Wolfgang Zech

Abstract

Indonesia: Survey on the Effect of Charcoal to Tree Growth and Charcoal Production in West Kalimantan (1.3 mb pdf)
Carbon Fixing Forest Management project
Demonstration Study on Carbon Fixing Forest Management in Indonesia
Cooperation Project between Forestry Research and Development Agency (FORDA), Ministry of Forestry, Indonesia, Japan International Cooperation Agency (JICA)
Collaboration with Yayasan Dian Tama December 2005

FOREWORD

Agri-char / Bio-char References: On its potential for carbon sequestration, improved soil fertility and sustainable (carbon-negative) energy production
Rick Davies, updated February 21, 2007

Good link site.