Biochar is fine-grained or granular charcoal made by heating vegetative biomass, bones, manure solids, or other plant-derived organic residues in an oxygen-free or oxygen-limited environment and used as a soil amendment for agricultur- al and environmental purposes.
It is a new word to describe fine-grained, highly porous charcoal made from biological material (biomass), high in organic carbon. This excludes fossil fuel products, geological carbon and industrial synthetics (plastics).
Biochar is pyrolysed feedstock under limited or no supply of O2 (Lehmann and Joseph, 2009)
This concept comes from-Terra Preta- ancient soils of the Amazon. (Glaser et al., 2001 and 2002; Lehmann, 2007).
2. What is Biochar
• Biochar is a new word to describe fine-grained, highly
porous charcoal made from biological material (biomass),
high in organic carbon. This excludes fossil fuel products,
geological carbon and industrial synthetics (plastics).
• Biochar is pyrolysed feedstock under limited or no supply
of O2 (Lehmann and Joseph, 2009)
• This concept comes from-Terra Preta- ancient soils of the
Amazon. (Glaser et al., 2001 and 2002; Lehmann, 2007).
3. Biochar characterized as
 Recalcitrant aromatic structure (Downie et al., 2012; Lehmann, 2007),
 Highly porous and fine grained (Inyang et al ,2012),
 Hydrophobic in nature (Qiu et al., 2009),
 Small molecule with few fused aromatic rings (6-7)
(Mao et al., 2012; Hiemstra, 2012)
 Variable in different composition (Atkinson et al., 2010; Lehmann
and Joseph, 2009).
5. Bangladesh and Biochar
In Bangladesh,
 Soil OM status: most soil<1.5%, and some soils <1%
(Fertilizer recommendation guide, 2005 ; 2012. p 48),
 Rapid decomposition of organic matter
 Deficiencies of macro and micro nutrients (Islam, 1992; Khan et
al.,1997),
 Nutrient leaching and volatilization .
 Due to biochar application organic matter status and
nutrient availability could be increased.
 A primary purpose for biochar is as soil enhancement to
help retain nutrients and water , and habitat for the soil
food web.
 Properly made and used, biochar can mitigate climate
change and other environmental effects .
6. Soil amendment and C-sequestration
• Increased fertility (Glaser 2007; Sombroek et al. 2002)
• C- sequestration for >100yrs (Downie et al.
2012;Lehmann 2007)
• 12% GHS reduction per year (Woolf, et al., 2010)
Environmental Issues
Pyrolysis
Bioenergy
• Bioenergy generation from biomass pyrolysis
(Lehmann,2007, Laird,2008)
Waste management
• Use of waste for biochar production (Lehmann
2007)
7. Why it is good for plant ?
Biochar is an organic soil amendment enhancer that:
 Increase soil fertility and agricultural yields
 Significantly enhances plant growth & root development.
 Boosts plant nutrient retention.
 Improves soil structure and stability.
 Improves soil water holding capacity & permeability.
 Retains nitrogen and phosphorus in the soil.
 Helps healthy activity of soil micro-fauna & flora.
 Suppresses odour & breaks down pollutants from soil.
8. Biochar stove
Easy way of Production
An Example of Biochar production what
I did in my Experiment:
 Forty five (45) kg dry sawdust,
 Used fuel was 12 kg fuel
 Average residence time was (5 hours)
 Temperature was >350 0 C
(approximately),
 Produced biochar was 10 kg
10. Nutrient
availability &
retention
(Blackwell et al., 2010)
Water holding
capacity (Brewer et al.,
2012; Major et.al, 2011)
Crop yield (Asai
et al., 2006; Tagoe et al.,
2008)
Habitat for
Microorganisms
(Lehmann et al. 2011)
Reduces nutrient
leaching
(Brockh et al., 2010)
Physical
properties of
soil
(Busscher et al., 2010)
C-sequestration
(Downie et al. 2012;
Lehmann, 2007)
Soil pH & CEC
(Glaser et al.,2002;
Biochar with Soil
11. Fe & Al hydr(oxydes)
PO4 –OM competition
Soil organic matter
Humic acids
Fulvic acids
Humin
Soil
organisms
Organic
inputs
(biochar)
ElevatedN
supply
Mineralization
Nutrient
uptake
Immobilization
Inorganic
inputs
(N+P+K)
ElevatedPO4
Decomposition
NH4
+
High CEC and
elevatedIon
binding to organic
matter
ElevatedBNF
Figure 2. Schematic representation of Biochar alone with NPK fertilizers activity in soil for plant
growth and biological nitrogen fixation (BNF).
2
3
1
12. Biochar has high CEC. So it can increase nutrient
retention capacity and increase nutrient use
efficiency by binding NH4
+
Biochar increase P availability as they release
small molecules of organic matter, which are more
competent for PO4 .
The C/N ratio of Biochar is high as a result, part of
the mineral is immobilized . That is biochar
application increase BNF. Moreover, Biochar itself
has a positive effect on nodulation due to
favourable condition for symbiotic bacteria.