This document summarizes the state-of-the-art understanding of biochar. It discusses biochar properties, biochar systems like Terra Preta soils, practical examples of biochar use that increase yields and soil carbon, and the scientific evidence that biochar increases yields, plant growth, carbon sequestration while reducing emissions like N2O. The document concludes that biochar has significant potential for climate change mitigation through carbon negative sequestration and should be further supported for use in agriculture and land management.

1. Bruno Glaser
Biochar – state-of-the-art
Biochar – state-of-the-art
Bruno Glaser
Content:
➢ What are we talking about? => Biochar properties
➢ Where does it come from? => Biochar systems
➢ How can it be sustainably used
=> Practice examples
➢ What do scientific studies tell us?
=> Scientific results
➢ Is it good for the climate? => C negative
➢ Take home => Summary
➢ For full biochar state-of-the-art review see:
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https://www.youtube.com/watch?v=ex2sFye9t_0&t=248s (deutsch)
https://www.youtube.com/watch?v=zf5rbSJ3lHo&t=12s (english)

2. Bruno Glaser
Biochar – state-of-the-art
Biochar properties
2/13
Biochar Eruope (2010)
Porosity
Condensed aromatics
Functional groups
Labile organic carbon
Ash
 Water storage
 C storage
 Nutrient storage
 Food for microbes
 Immediate fertilizer
Structure Ecosystem function
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

3. Bruno Glaser
Biochar – state-of-the-art
Terra Preta – most prominent and successful biochar system
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Amazonian
Dark Earth
Ferralsol
Biochar
Excrements
Litter
Organic wastes (nutrient-rich)
Microorganisms
Food leftovers Bones
Incorporation of tremendous amounts of N and P (15 Mg ha-1)
Incorporation of charred residues (BIOCHAR, 50 Mg ha-1)
Microbial recycling (organic matter stabilization, mineralization)
Relic of ancient settlements and concept of nutrient reycling
Glaser et al. (2001) Naturwissenschaften 88: 37–41
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

4. Bruno Glaser
Biochar – state-of-the-art
Modern Terra Preta concept
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© Biochar Europe (2010)
 Biochar system
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

5. Bruno Glaser
Biochar – state-of-the-art
Cascade use of biochar
5/13
Seitz et al. (2017) Potential Analysis of Biochar Systems for Improved Soil and Nutrient Management in Ethiopia
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

6. Bruno Glaser
Biochar – state-of-the-art
Small-scale biochar system (coffee or sesame residues)
6/13
Seitz et al. (2017) Potential Analysis of Biochar Systems for Improved Soil and Nutrient Management in Ethiopia
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

7. Bruno Glaser
Biochar – state-of-the-art
Model of a large-scale biochar system based on flower residues
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Seitz et al. (2017) Potential Analysis of Biochar Systems for Improved Soil and Nutrient Management in Ethiopia
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

8. Bruno Glaser
Biochar – state-of-the-art
[Mg ha
-1 dm
-1
] Biochar 4 Biochar 2 Biochar 1 Compost Control
Compost
32.5
32.5
32.5
32.5
0
Biochar
20
10
5
0
0
Biochar amount efffect (NE Germany 2009)
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 Up to 80% higher yields
 Soil organic carbon tripled (1 –> 3%)
 Soil water holding capacity doubled (60 –> 120 L m2)
Liu et al. (2010) Journal of Plant Nutrition and Soil Science 175: 698-707
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

9. Bruno Glaser
Biochar – state-of-the-art
Practical recipies (N Germany 2012)
Glaser et al. (2015) Agron Sust Dev 35: 667-678
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 At least as good as mineral fertilizer
(mineral fertilizer used as control !!!)
 Soil organic carbon tripled (3 –>9%)
 Nutrient uptake improved
 Heavy metal uptake reduced
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

10. Bruno Glaser
Biochar – state-of-the-art
Most important biochar effects (summary of biochar meta-analysis)
10/13
https://www.youtube.com/watch?v=zf5rbSJ3lHo&t=12s
➢ +10% Yield increase
➢ +40% Tree growth
➢ +60% C sequestration
➢ Up to -90% N2O emission (amount-dependent)
➢ Up to -60% Nitrate leaching (amount-dependent)
➢ Up to +800% Plant P availability (amount-dependent)
➢ -30% Cd uptake into plants
➢ -10% Soil density
➢ +20% Soil water holding capacity
 Overall positive effects
 Why biochar should not be used or at least be allowed in agriculture?
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

11. Bruno Glaser
Biochar – state-of-the-art
Biochar as climate change mitigation option
11/13
CO2 capture before or after burning
Fossil fuels Geological stoarage
Biomass
Burning / Biogas
Circular system, however further CO2 emission, because not 100% energy-efficient
Biochar
Biomass Pyrolysis Energy !!!
Biochar
CO2
Glaser, B., Parr, M., Braun, C., and Kopolo, G. (2009). Biochar is carbon negative. Nature Geoscience 2, 2-2
Carbon
Capture and
Storage (CCS)
Biofuels
Open system, extraction of CO2 from the atmosphere via photosynthesis (= C-negative !!!)
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home

12. Bruno Glaser
Biochar – state-of-the-art
Potential of biochar for C sequestration
Tisserant et al. (2019) Land 8:179
 Biochar is C-negative and ready to use…
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home
12/13

13. Bruno Glaser
Biochar – state-of-the-art
Summary of biochar effects on ecosystem functions
13/13
Seitz et al. (2017) Potential Analysis of Biochar Systems for Improved Soil and Nutrient Management in Ethiopia
Properties ♦ Biochar systems ♦ Practice ♦ Science ♦ Climate ♦ Take home