Glaser et al ., 2007 Biochar Meta-AnlysisStudies: 23 studies - PowerPoint PPT Presentation

Glaser et al ., 2007

Biochar Meta-AnlysisStudies: 23 studies (2009-2011) (with 7 field studies) Jeffery et al ., 2011 Agriculture, Ecosystems & Environment Biederman et al ., 2013 GCB Bioenergy RR B = relative biochar effect = ln (Biochar/Control) 371 Independent studies

Key Meta-Analysis Papers • An analysis done by Dr. Humin Zhou et al. in 2017 found that biochar increased Microbial Biomass Carbon an average of 26% from 413 academic research papers. • Dr. Xiaoyu Liu and a series of other researchers published a paper examining 238 studies of biochar's influence on plant productivity. They found that vegetables increased by an average of 28.6%, and that legume crops, such as peas, beans, and vetch, increased productivity by an average of 30.3%.

Biochar Studies: Soil nutrient retentions …... Gao & DeLuca, 2016 Advances in Plants & Agriculture Research

Key Considerations with Current Research • The application of biochar to soils has also been shown to influence nutrient retentions. • Short-term studies, pot and column trials in lab or greenhouse environment, very few are field studies. • Also longer term field trials are in ag experiment stations using conventional farming approaches. Very few studies are conducted in the field in active organic farming systems and as a part of a holistic closed loop system.

Field Trials Design @ Each Farm 1m 1m 30 cm buffer Block 1 Block 2 Block 3 Block 5 Block 4 Poultry litter (70 kg N ha -1 poultry litter) Control Biochar (20 t ha -1 ) Biochar charged with poultry litter (20 t ha -1 + 70 kg N ha -1 )

Photo: Si Gao

Soil microbial biomass C (mg kg -1 ) Charged char 47% + 7% + 46% + Biochar 20% + Poultry litter 2016 2015 Control 0 50 100 150 200 250 300 350

Soil total C (g kg -1 ) 35% + Charged char 40% + 35% + Biochar 45% + Poultry litter 2016 Control 2015 0 10 20 30 40 50 60 70

Average soil enzyme activity* Charged char 28% + Biochar 24% + Poultry litter 2016 Control *the geometric mean of beta-glucosidase, dehydrogenase, phosphatase, and urease. An overall index for soil 0 20 40 60 80 100 120 140 biological activity.

Soil potentially mineralizable N (mg kg -1 14d) Charged char 63% + 80% + 65% + Biochar 115% + Poultry litter 2016 2015 Control 0 2 4 6 8 10 12 14 16 18 20

Soil soluble inorganic P* (mg kg -1 ) Charged char 160% + Biochar 35% + Poultry litter 2016 2015 Control 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 *exist in soil solution, readily available.

Soil water-hoding capacity 18% + Charged char 13% + 20% + Biochar 5% + Poultry litter Control 0% 20% 40% 60% 80% 100% 120% 2016 2015

+ -N below rooting zone Accumulated NH 4 (µg per resin capsule) 60 Waldron2016 50 13% - 33% - 40 30 20 10 0 Control Poultry litter Biochar Charged char

Average yield per treatment plot (kg) Charged char 13%+ 28%+ Biochar Poultry litter 2016 Control 0 1 2 3 4 5 6 7 8 9

Nutrient Density in Dry Beans 2015 Micro Nutrients in Micrograms 160 140 120 100 80 60 40 20 0 Cu Fe Mn Zn Ca Dry Beans @ QFC Dry Beans @ San Juan Islands Dry Beans @ San Juan Islands Carbon Farming