PHOTO: Burkhard Schmidt-BrückenPHOTO: Burkhard Schmidt-BrückenInstitute of Material Science/TU Institute of Material Science/TU

Dresden Dresden COLOR: Christian Schurig/ UFZCOLOR: Christian Schurig/ UFZ

HyphomicrobiumHyphomicrobium bacteriabacteria ( (yellowyellow)) grow on solid surfaces & grains. grow on solid surfaces & grains.

When bacteria cells die, When bacteria cells die, they deform or fragment they deform or fragment until only cell envelopes remain.until only cell envelopes remain.

Small fragment shells (Small fragment shells (redred) ) form micro-particle matrix in soils. form micro-particle matrix in soils.

Contributions of bacteria remnants to soil fertility are underestimated

It was assumed Soil Organic Matter is mostly decomposed plant matter which directly converts to humic substances

Lab experiments and field tests refute this. Easily degradable plant matter is converted to microbe biomass, which then provides source material to Soil Organic Matter

40% of microbe biomass is converted to Soil Organic MatterRemains of dead bacteria are far greater in soils than previously assumed.

Soil Organic Matter is the largest fraction of carbon in the biosphere, and plays key roles in soil fertility and agricultural yields.

Microbes also a key factor to control CO2 concentration in the atmosphere.

Climatic change can be slowed or accelerated, according to soil management

Research report in professional journal BiogeochemistryHelmholtz Centre for Environmental Research, Switzerland

Technical University of Dresden, GermanyUniversity of Stockholm, Sweden

Max Planck Institute for Developmental Biology, GermanyLeibniz University, Hanover, Germany

Microbes & ClimateMicrobes & ClimateBiochar PropertiesBiochar Properties

Most plant debris in fertile soil is rapidly processed by microbes (bacteria)leading to more bacteria and thus, more cell fragments. This results in more Soil Organic Matter.

Although most organic carbon is produced mainly by plants, a large part is residues of bacteria and fungi. This underscores the importance of bacteria in all types of soil.

Further, microbes are important for global climate: Decay of organic matter results in mineralization + CO2 + H2OCO2 escaping annually to the atmosphere from decaying Soil Organic Matteris in the same range of scale as annual greenhouse gas emissions.

Thus, progress in climate protection isn’t achievable without first protecting soil.

residential refuges for micro-orgamismsresidential refuges for micro-orgamisms

Spores ofSpores ofG. Margarita G. Margarita

germination higher than on soilgermination higher than on soil

biochar provides preferred habitat for soil microbesbiochar provides preferred habitat for soil microbes

Bacteria & BiocharBacteria & BiocharBiochar PropertiesBiochar Properties

PHOTO: Makato Ogawa, Japan, 1991PHOTO: Makato Ogawa, Japan, 1991

Dr. Makato OgawaDr. Makato Ogawa19911991

Bacteria populations Bacteria populations show sharp increase show sharp increase

after charcoal additionafter charcoal addition

3-fold 3-fold increaseincrease

Biochar PropertiesBiochar PropertiesBacteria & BiocharBacteria & Biochar

Beijerinckia & OgawaBeijerinckia & Ogawa19921992

NitrogenNitrogen-fixing bacteria-fixing bacteria

• RhizobiaRhizobia (symbiotic) (symbiotic)

• FrankiaFrankia (symbiotic) (symbiotic)

• AzotobactersAzotobacters (free-living) (free-living)

• AzospirilimAzospirilim (free-living) (free-living)

Amino Acid synthesisAmino Acid synthesisAmino Acid conversionAmino Acid conversionProtein digestion: Protein digestion: proteolaseproteolase

ReductionReduction OxidationOxidation

CationCation++//AnionAnion−−

ConversionConversion

Bacteria & Bacteria & NitrogenNitrogen Cycle CycleBiochar PropertiesBiochar Properties

Molybdenumnitrogenase enzyme

effect on soybean root growth & noduleseffect on soybean root growth & nodules

PHOTO: M. Ogawa, Kansai Environmental, JapanPHOTO: M. Ogawa, Kansai Environmental, Japan

Nitrogen-fixing BacteriaNitrogen-fixing BacteriaBiochar PropertiesBiochar Properties

Despite a surge of research recently, challenges to soil biologists remain daunting. Despite a surge of research recently, challenges to soil biologists remain daunting.

Even basic biodiversity below ground—species diversity and distributionEven basic biodiversity below ground—species diversity and distribution——remains far more obscure than for life above the soil surface. remains far more obscure than for life above the soil surface.

Soil fungi are a case in point: key component of soil ecosystems, Soil fungi are a case in point: key component of soil ecosystems, its global species diversity has been estimated by various methods. its global species diversity has been estimated by various methods.

Fungi communities are highly structured, based on pH, soil horizon, species, Fungi communities are highly structured, based on pH, soil horizon, species, and other conditions of the understory plant community. and other conditions of the understory plant community.

Fungi study in Alaskan boreal forest soils suggests previous estimates of diversityFungi study in Alaskan boreal forest soils suggests previous estimates of diversityat .5 to 1.5 million species need to be revised upward. at .5 to 1.5 million species need to be revised upward.

DNA data from fungal samples found over 1000 discrete fungal taxa—DNA data from fungal samples found over 1000 discrete fungal taxa—many more than estimated from non-molecular data. many more than estimated from non-molecular data.

A fungus:plant ratio of 17:1 extrapolates to at least 6 million fungal species globally.A fungus:plant ratio of 17:1 extrapolates to at least 6 million fungal species globally.This suggests 98% of fungi have yet to be discovered.This suggests 98% of fungi have yet to be discovered.

Diversity Down BelowDiversity Down BelowAndrew M. SugdenAndrew M. SugdenEcology: Ecology: Ecol. Monogr.Ecol. Monogr. 84, 3 (2014) 84, 3 (2014)

Microbial ColonizationMicrobial ColonizationBiochar PropertiesBiochar Properties