Transcript Slide 1
Terra Preta de Indio Carbon “darkSoil earth” Mystery of the Amazon Charcoal Amazon Basin, Brazil How did the native Amazon tribes create these Soil Minerals (Portuguese) reduced carbon remarkably fertile and productive soils? 1867: Ballard S. Dunn, Confederate exile Local farmers prize terra preta High Carbon (SOM) content Conservation Grassland Terra Preta •updug up Home and sold potting soil book: Brazil: for as Southerners Ferralsol to 9% Minnesota •compared yields up to three fold asdark great as lauds high fertility of.5% Amazon soil with in other soils How have these remarkablesometimes soils sustained surrounding infertile tropical soils over 20% their sustained fertility in intensive use tocenturies? twoHerbert meters deep 1879: explorer Smith fertility and productivity for •one five tales of Amazon in Scribner's Monthly: Small Patches “extraordinary fecundity of (50 cane fields… Age: 800-4000 years • average: 20 hectares acres) What can we learn from these remarkable to dating (charcoal) “stalks tenhectares feet high… big as a wrist… •radio-carbon 350 (865soils acres) reported research: 6000 years near settlements & in onAmazon… bluffs "rich•recent ‘terra preta’… best sustain soil fertility and productivity today? pottery sherds “fine,• embedded dark loam… often two feet thick" • animal & fish bones, cultural debris High nutrient content 1966: Wim Sombroek (Dutch;1944-2003) Can this method to create tropical provide Calcium &soils Phosphorus Made from Ferralsol or Acrisol published his book: Amazon Soils Nitrogen predominant soils inpreta Amazon first •scientific study of terra insights to improve temperate climate soils? Cation Exchange Capacity (CEC) • acidic, notoriously infertile 1992: Sombroek publishes his first book • poor nutrient capacity on terracarbon preta for in carbon Can this method to sequester soilsequestration help High Microbial activity Aerial Surveys 2002: Sombroek forms Terra Preta Nova us reverse global warming and climate change? reef” • up toon 10% of total land area to“microbial use char farms as a carbon sink nitrogenous bacteria fixing) • able to feed 5-10 (nitrogen million people click 2007: first international biochar conference to continue Terra Preta Increased is biochar a Fertility nutrient? • higher Phosphorus & Calcium In normal soil, biochar breaks down very slowly • higher Nitrogen (oxidation,weathering & digestion) • –increased nutrient availability over centuries, rather than months • lower acidity Biochar isn’t consumed by soil life • higher pH buffering •Biochar water retention freshly made is sterile, • physical structure with no biological activity • biological– habitat (microflora & fauna) no microbes Adding only biochar to soil retards plant growth for up to two years Fertilizers must be added with biochar terra preta Biochar is a sponge acrisol toAmazon hold water & nutrients, typical soil infertile and a substrate to provide habitat & housing for microbes biochar click to continue Terra Preta Global Research 2001 biochar benefits cation exchange capacity increased (Glaser) water-holding capacity 18% increase (Glaser) biomass growth 266% increase (Steiner 2nd year) 324% increase (Kishimoto & Sugiura) plant nitrogen uptake doubled (Steiner) click to continue farm chemical runoff reduced (Yelverton) Terra Preta Research t/ha 3-Year Field Trials 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 Rice & Sorghum with charcoal 366% without charcoal 267% 881% Biomass Yield Total Christoph Steiner1; W. G. Teixeira2; Johannes Lehmann3; W. Zech1 1 Institute of Soil Science, Univ. of Bayreuth, Germany 2 Embrapa Amazonia Ocidental, Manaus, Brazil 3 Dept of Crop and Soil Sciences, Cornell Univ., USA click to continue Terra Preta Research Bark Biochar & Fertilizer biochar + NPK biochar + NPK NPK control control NPK Effect of bark biochar and fertilizer on plant growth and soil properties in south Sumatra click Yamato 2004 unpublished to continue