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BookreviewBiocharforEnvironmentalManagement:ScienceandTechnology,JohannesLehmann,StephenM.Joseph(Eds.),(2009),Earthscan,LondonUK,448pThiswell-conceivedandtimelybookisthefirsttodescribethescienceandtechnologyforturningbiomassintocharcoalandapplyingitasasoilamendmentinordertoimproveagriculturalproductivity,providearenewableenergyresource,managewastematerials,andmitigategreenhousegas(GHG)emissions.Thisbookisessentialforanyoneinterestedinthesetopics,asitpaintsa“big-picture”andpresentstheeconomicsofbiocharproductionanduse,andtheappropriateinternationalpolicyapproachestoimplementation.Biocharcreatesrolesforforestryinthedevelopedanddevelopingworlds,withimplicationswellbeyondtheforestrysector.Theeditors–soilscientistLehmannandrenewableenergyengineerJoseph–pointoutthatdivertingmerelyonepercentoftheabilityofterrestrialvegetationtocaptureandstore(i.e.,sequester)atmosphericcarbonwouldmitigatenearly10%ofhuman-inducedcarbonemissions.1.IntroductionWhenorganicmatter(wood,manure,orleaves)isheatedinaclosedcontainerwithlittleornoavailableair,charcoalisproducedbyaprocesscalledpyrolysis.“Biochar”isatermcoinedrecentlytodescribetheapplicationofcharredorganicmaterialtosoilinadeliberatemannertoeitherimprovesoilpropertiesortostorecarbon.Thisissimultaneouslyanancientconceptandanewwayofthinkingaboutenvironmentalmanagement.TheTerraPretadeIndio(Amazo-nianDarkEarths),forexample,remainmoreproductivethannearbylandsmorethan1000yearsafterbiocharwasapplied.IntheForeword,world-renownedacademicianTimFlannerylaudsbiocharas“thesinglemostimportantinitiativeforhumanity'senvironmentalfuture…allow[ing]ustoaddressfoodsecurity,thefuelcrisisandtheclimateproblem,andallinanimmenselypracticalmanner.”Theeditorsintendthebooktoadvancetheapplicationofbiocharforenvironmentalmanagement,andinourviewthatislikelytohappen.Althoughtheeditorsexpressenthusiasmforbiochar'spotentialintheintroductorychapter,theyhavecarefullyeditedthe22chapterstoadherecloselytothefactswhilemeetingthestatedobjectivetocomprehensivelycaptureandsynthesizeinformationaboutbiocharscienceandtechnologyandmakeitmoreaccessibletoawideraudience.Thebookissubdividedintofourareas:11)basicphysical,chemical,andbiologicalcharacteristicsofbiochar;2)multipleapproachesforbiocharproductionandapplication;3)environmentalprocessesthatareaffectedbybiochar,andthechangesthatinfluencebiochar'slongevityandeffectivenessinimprovingsoilfertility;and4)implementationofbiochar,withchaptersoncommercialization,GHGemissionsoffsettrading,economicsofbiocharsystems,andpolicyopportunitiesandconstraints.Thechapterswerewrittenby50authorshailingfromAustralia(19),USA(15),UK(4),variousEuropeancountries(5),Canada(2),SouthAmerica(2),NewZealand(2),andAfrica(1).Thebookmaintainsanappliedfocus,concludingeachchapterwithasectiononhowbiocharcanbeusedforenvironmentalmanagement.Thismotivatesthereadertothinkabouthowbiocharaffectsecosystemsasawhole,andhoweachfacetisinterconnected—aperspectiveoftenlostinnarrowly-focusedappliedresearch.Chaptersconcludebyreplyingtothequestion,whydoIneedtoknowthisaboutbiochar?Thismakesrelevantanumberoftopicsthatinitiallymayseemtrivial.2.ScienceOnerecurringthemeisthatbiocharresearchisinitsinfancyandneedsextensive,furtherresearchbeforeappliedonalargescale.Anotheristhatbiocharpropertiesarehighlyvariable–asillustratedinseparatechaptersonthephysical,chemical,biologicalandnutrientproperties–dependingontheinitialfeedstockproperties,andtheconditionsoftime,temperatureandpressureunderwhichtheywereprocessed.Suchvariabilityisastrengththatprovidesopportunitiestocalibratebiocharproductiontomatchthedesiredpropertiesofbiocharforspecificmanagementapplications.Feedstocktypescanbeblendedtocreatedesiredbiocharpropertiesandpotentiallyhighernutrientcontentstosuitdifferentvegetationandsoiltypesaswellasdiversemanagementobjectives.Agendasforfurtherresearchinbiocharscienceandtechnologyareprovidedattheendofalmosteverychapter.Areaswithinsufficientsupportorambiguousdataareclearlyoutlinedandaddressed.Innowaydoesthebooktrytomisleadthereader;allpositiveandnegativeenvironmentaleffectsofbiocharareaddressedwithamplesupportfromtheliterature.Thisisparticularlyrefreshing,consideringthatsomerecentmediacoverageinaccuratelydescribesbiocharasapanaceaforclimatechangemitigationaswellasallsoildegradationproblems.3.TechnologyTheBiocharSystemschapterwrittenbytheco-editorsisenlightening.Thevarietyofbiocharsystemsareverydifferentintermsoftheresourcebase,conversiontechnologyandproductuse,illustratedbysevenbriefprojectcasestudies.Inregionsthatrelyonbiomassenergy–mostofruralAfricaandlargeareasinAsiaandLatinAmerica–pyrolysisbioenergyprovidesopportunitiesformoreefficientenergyproductionthanwoodburning,offeringcleanheatforcookingfoodandloweringindoorsmokepollution.Aswellassmall-scalepyrolysiskilnsscaledtosubsistenceagriculturehouse-holds,casestudiesincludelarge-scalebioenergyproductioninte-gratedwithacementplantinoneexampleandanintegratedlumberandpulpmillcomplexinanother.Theformerpyrolizes100,000drytonsofbiomassperyear;thelatter,162,000drytonsperyearofresiduesfroma200,000haA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