H.C. Lee, R. Walker, S. Haneklaus, L. Philips, G. Rahmann and E. Schnug / Landbauforschung - vTI Agriculture and Forestry Research 3 2008 (58):145-152

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Organic farming in Europe: A potential major contribution to food security in a scenario of climate change and fossil fuel depletion

HowardC.Lee�,RobinWalker��,SilviaHaneklaus���,LoisPhilips�,GeroldRahmann����andEwaldSchnug���

� Hadlow College, Hadlow, Tonbridge, Kent TN11 0AL, UK, Email: howard.lee@hadlow.ac.uk

�� ScottishAgriculturalCollege(SAC),CraibstoneEstate,Bucksburn,Ab- erdeenAB219YA,Scotland

��� InstituteforCropandSoilScience,JuliusKühn-Institute(JKI),FederalRe- searchCentre forCultivatedCrops,Bundesallee50,D-38116Braun- schweig,Germany

���� InstituteofOrganicFarming,HeinrichvonThünen-Institute(vTI),Federal ResearchInstituteforRuralAreas,ForestryandFisheries.Trenthorst32, D-23847Westerau,Germany

Summary

Prevailingevidenceindicatesthatthecombustionofcoal,oilandnaturalgascontributestoglobalgreenhousegas(GHG)emissionsandassociatedclimatechange,includingincreasedinstabilityofweather,(extremeweatherevents-EWEs)suchastemperaturefluctuationsandadversedis-tributionsofrainfall. ‘Peak’modelsfortheavailabilityofoilandnaturalgasindicatethatshortagesarelikelyinthenearfutureand,combinedwithEWEs,maythreatentheproductivityofEuropeanagriculturalsystems.Theproduc-tionofmineralfertilizerandpesticides,andfuelforagri-culturalmachinerywill be affected aswill the transportofagriculturalcommoditiesfromproducertoprocessortoconsumer.Thiswillputfoodsecurityinhighlypopulatedtownsandcitiesatrisk.Itisconcludedthatfoodproduc-tion and consumption in Europe, post peakoil,will de-penduponmorelocalisedfarmingthatisrelativelyresilienttoEWEs,canoperateeffectivelywithreducedinputsandisadaptabletolikelyincreasesinweed,pestanddiseaseproblems.toItisproposedherethatorganicfarmingcanbestsatisfytheseneeds.Intermsofsustainablefoodpro-ductionpoliciesinEurope,itissuggestedthatthereneedstobeagreater emphasisupon regional, resource-basedorganicproduction,andwithaspecialfocusupongreat-erenergyandwateruseefficiency.Itisthereforerecom-mendedthaturgentaction isrequiredto investigatethefurtherdevelopmentoforganic farming inpostpeakoilEurope,andbeforethesecurityofcurrentfoodproductionanddistributionsystemsiscompromised.

Keywords: food security, fossil fuels, depletion, organic farming

Zusammenfassung

DieVerbrennungvonKohle,ÖlundErdgasträgtzurFrei-setzung von klimarelevanten Treibhausgasen und einemanthropogenverursachtenKlimawandelbei,welchersichunterandereminextremenWitterungsbedingungennie-derschlägt.SogenanntePeak-Modellezeigen,dassdieÖl-reserveninunmittelbarerZukunftknappwerden.Zusam-menmitextremenWitterungsbedingungengefährdetdiesdie Produktivität landwirtschaftlicher Betriebe in Europa.Besonders die energieaufwendige Produktion vonMine-raldüngerundPestiziden,aberauchdieBereitstellungvonTreibstoff für die Landmaschinenwäre davon betroffen.DerTransportlandwirtschaftlicherErzeugnissevonProdu-zenten zuVerarbeitern undVerbrauchernwäre insoferneingeschränktalserdölabhängigerTransportnurbedingtstattfindenkönnte,sodassdieausreichendeVersorgungderBevölkerungmitNahrungsmitteln ingroßenStädtenundMetropolengefährdetwäre.Somitergibtsichzukünf-tigdieNotwendigkeitzurräumlichenNähevonNahrungs-mittelerzeugung und -verbrauch, wobei AnbausystemenichtnurrobustgegenüberextremenWitterungsereignis-sen(Trockenheit,Hochwasser,ungünstigeNiederschlags-verteilung sowie veränderten Umweltbedingungen (Un-krautdruck,neueKrankheitenundSchädlinge)seinsollten,sondernauchmiteinemreduziertenInputanRessourcenwirtschaften und die Nahrungsmittelsicherheit der an-grenzendenBevölkerungsicherstellenmüssen.DieÖkolo-gischeLandwirtschaftversucht,diesemAnspruchgerechtzuwerden.HierzumusssichderÖkologischeLandbaueinehöhereEffizienzundStabilitätentwickeln.Zunächstistesnotwendig, das Leistungsvermögen der ÖkologischenLandwirtschaft unter limitierten fossilen Rohstoffreservenzuanalysieren,bevorNahrungsmittelproduktionundVer-sorgungssystemeinEuropagefährdetsind.

Schlüsselworte: Nahrungsmittelsicherheit, fossile Brennstof-fe, Erschöpfung von Reserven, Ökologische Landwirtschaft

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Introduction

European nations depend upon the consumption oflargequantitiesof fossil energy, accounting for approxi-mately three quarters of the total carbon dioxide (CO2)released into the atmosphere (Hammons, 2006). Fossilfuel consumption by European farming is known to beassociatedwiththereleaseofCO2,thoughthisaccountsforonlyabout5%of total fossilenergyuse (Pinstrup-Andersen,1999citedinDalgaardetal.,2001).However,farmscanalsoleadtoother emissionsofGHGs,suchasnitrousoxideandmethanefromthelandand/orlivestock(Olesen&Bindi,2002).Gaseousemissionsfromfarmlandandruminantsareandalwayshavebeenanaturalpartofbiologicalprocesses: it isemissions fromfossil fuels thatareconsideredinthispaper.In2005,Germanagriculturecontributedapproximately

6.3%toanthropogenicGHGemissions(133mtequiva-lent) (Smithetal.,2007).However,organic farminghasbeendemonstrated tocontribute less toGHGemissionsthancomparablenon-organicfarmingsystems(Rahmannetal.,2008).Paradoxically,thoughtheuseoffossilenergybyourso-

cietyhasincreasedrapidlyinrecentyearsandcontributedto an ongoing process of climate change, the probablefuturescenario isoneofdepletionofreserves(Guseoetal.,2007)andreducedavailability,includingthatforagri-culture.Thefocusofthispaperisthereforeonhowagriculture

inthe2�stcenturycanadapttoalegacyofclimatechangeduetopriorcombustionoffossilfuelsbutwithinalikelyfuturescenarioofreducedsuppliesofthosesamefuels.

Climate change, fossil fuel depletion and the implica-tions for farming in Europe

Climate change

Climatechange isnowwidelyacceptedasarealphe-nomenon (e.g. Dietz et al., 2007), involving increasedtemperaturesandsummerdroughts(Fuhrer,2003).Thereare also increasing references to the negative effects ofclimatechange,includingextremeweatherevents(EWEs),onagriculture(IAASTD,2008).Olesen&Bindi(2002)con-cludethat:

“Thepossibleincreaseinwatershortageand(EWEs)maycauselowerharvestableyields,higheryieldvariabilityandareductioninsuitableareasfortraditionalcrops.”(Ole-sen&Bindi,2002,p.257)

Extremes of temperature can be a problembut varia-tionsinrainfallhavebeenshowntobemorecritical,such

asresultsfromtheBroadbalklongtermcerealexperiment,Rothamsted (UK),whereaclearnegativecorrelationhasbeendemonstratedbetweencerealgrainyieldsandrain-fall (Chmielewskia & Potts, 1995). A recent review byMotha(2007)concludesthattheimplicationsofclimaticvariation are severe. For future planning, this researcherstatesthat:

“Itisimperativethatproactivemitigationmeasuresandadaptationstrategiesbedevelopedbasedonsoundsci-entificknowledgeabout thehazards (ofEWEs) so thatpreparednessmeasurescanbeimplementedtocountertheireffects.”(Motha,2007,p.307)

Fossil fuels

The concept of ‘peak oil’ is now well documented(Greeneet al., 2006;Brandt, 2007;Guseoet al., 2007)and the consensus is that suppliesmay become limitedbefore2010,asthepeakispassedandworldproductiondeclines (Campbell, 2006). A similar depletion protocolhas also been predicted for natural gas (Bentley, 2002).WhatarethelikelyeffectsforagricultureinEurope?Cur-rently, the relatively high yields of European farming re-quirematching inputsofmineral fertilisersandsyntheticpesticides (Struik&Bonciarelli,1997), theproductionofwhichisinturndependentupontheuseoffossilenergy(Ramírez&Worrell,2006)andespeciallynaturalgas(Ahl-grenetal.,2008).Thereforeasfossilfuelsuppliesdecline,fertilizerandpesticide inputsmaybecomelessavailable,oratleastmuchmoreexpensive,leadingtoreducedappli-cationsandapotentiallynegativeimpactuponcropyields.Oilrestrictionsarealsolikelytospecificallyaffectthetrans-portationofgoods:

“Asconventionaloilsuppliesrundown…risingprices…could put transport in conflict…with other energy de-mands…”(Woodcocketal.,2007,p.1083)

Thus,thetransportationoffoodovermorethanafewkilometresmaybecomemuchmoreexpensiveandthere-foreunviable.

Proactive adaptation strategies: the potential resil-ience of organic farming systems to climate change and fossil fuel depletion

Adaptations to climate change

Animportantaspectofthedevelopmentofnon-organicfarmingsystemshasbeenagradualdeclineofsoilorganicmatter(SOM),especiallyforarablecropping.Thisisillus-tratedbyastudyofchangesinSOMforsouthernBelgium

H.C. Lee, R. Walker, S. Haneklaus, L. Philips, G. Rahmann and E. Schnug / Landbauforschung - vTI Agriculture and Forestry Research 3 2008 (58):145-152

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between1955and2005(Goidts&Wesemael,2007):

“Forunitsundercropland,anaveragedecreaseof5.8tC·ha-1wasmeasuredintheploughlayer(fromaninitialequivalent SOC (soil organic carbon] stockof46.4 tCha-1)…”(Goidts&Wesemael,2007,p.341)

Bycontrast,organicfarmsseemtobeassociatedwithrelativelyhigherandincreasingSOMs,demonstratedinapairedfarmstudybyArmstrong-Brownetal.(2000).High-erSOMsareknowntofacilitatebettersoilwaterretentionindroughts(Siegristetal., 1998)andenhancedinfiltrationcapacities(Schnugetal.,2006).Thus,organicallyfarmedsoilsseemmore likely toberesilienttovery loworhighrainfallEWEs.Thelatterisespeciallyimportant,sincestud-ies inGermanyhave shown thatwatershedsdominatedbyorganicfarmscontainsoilsthatarebetteratabsorbingsuddenprecipitation,reducingtheriskofsoilerosionon-farms,andmitigatingagainstfloodingfurtherdownthewatershed(Schnugetal.,2004;Schnugetal.,2006).

Energy dynamics

Whilstnutrientdynamicshavebeenwidelystudiedfororganicandotherfarmingsystems, investigationsofen-ergydynamicshavebeenmorelimited.Considerationoffossilenergyuseinagro-ecologicalsystemswaspioneeredbyOdum(see1971,1996andOdumet al.,2000).Clearly,itisinsufficienttomerelyconsiderfossilenergyconsumedunless it is comparedwith theenergyvalueof the foodproduced.Loake(2001)hasreviewedthisandasummaryis shown inTable1.This indicates thatenergy ratios fororganicfarmingarefarsuperiortothosefornon-organic.Morerecentstudiesarealsosupportive,thoughthediffer-encesaremoremodest(e.g.cropproductioninItaly(Sar-torietal.,2005);smallholderapricotproductioninTurkey(Gündoğmuğ, 2006); general farming inAustralia (Woodet al., 2006); and agricultural commodity production intheUK (Williams et al., 2006)). It is however importanttounderstandtheboundariesdefinedbyandlimitationsofsuchstudiesbeforedirectcomparisonsaremadewithotherfarmingsystems:thispaperisnotsuggestingthatallorganicfarmingismoreenergyefficientthannon-organicbutthatitisapotentiallyimportantfactorthatneedsfur-therinvestigation.Oftheorganicproductionexamplesre-viewedinthispaper,favourableenergyratioscanlargelybeattributedto lower indirect fossilenergyneeds,sincemanufacturedfertilizersandsyntheticpesticidesareomit-ted.Thisisnotsimplybecausetheyareprohibitedaspartoforganiccertification,butalsobecauseorganicsystemsare largely basedupon a pro-active rather than reactivemanagementregimeforweeds,pestsanddiseases.Thisorganic approach is also important for maximising the

availabilityofsoilnutrientsforcropsattheoptimumpointin the rotation (e.g. phosphorous: Walker et al., 2006;Stockdaleetal.,2006).Asglobalfossilfuelreservesbecomedepletedandthere-

foremoreexpensive,theincreasingcostofagrochemicalsandfertiliserswillencouragefarmerstolooktowardsal-ternative,lower-inputagriculture,includingtheprinciplesand techniquesdeveloped fromorganic researchand itspractice.

Table1:

EnergyratiosinUKfarming(a)

Ratio Conventionalsystem

Organicsystem

Componentsofratio

Grossenergy(b)

0.0002 0.0025

Energyout/energyin.Energy=netyield.Energyin=solarinputs,processinginputs,energyin,homerelatedenergy,fertilisers,fuels,electricity,machineryandfeedpurchased.(GJ).

Netenergy

0.�4 4.09

Energyout/energyin.Energy=netyield.Energyin=processinginputs,energyin,homerelatedenergy,fertilisers,fuels,electricity,machineryandfeedpurchased.(GJ).

Farmgate

0.34 4.29

Energyout/energyin.Energy=netyield.Energyin=fertilisers,fuels,electricity,machineryandfeedpurchased.(GJ).

DirectHuman

30-35 4.3Foodenergyoutputperman-houroffarmlabour(MJ/man-hour).

(a)AllratiosanddefinitionstakenfromLeach(1976).

(b)Grossenergyincludessolarinputsthatdespitebeinganimportantenergyinputare

usuallyomittedbecausetheydominateinputs,swampingtheratioandmakingitof

littlepolicyvalue(Leach,1976).

Source:Loake(2001)

It is therefore suggested that studies by Loake (2001)andothersneedtoberevisitedto:(i)accuratelyauditdi-rect and indirect fossil energy use for organic and non-organicfarmsand;(ii)striveforimprovedorganicsystemswhichmaximise energy capture,minimisedirect and in-direct fossil energy inputs and optimise internal energyrecyclingwithoutsacrificingyields.Areassessmentoftherelativeefficacyofenergyauditmethodsisalsoneeded,asconsideredbyWilson&Brigstocke(1980)andPervanchonetal. (2002).

Could a wider adoption of organic farming help im-prove food security in Europe?

IAASTD(2008)indicatesthatfoodsecurityisakeyfuturepolicyimperativeandcanbeachievedbymeasuresinclud-ingagreateremphasisonagroecologicalsystemssuchas

148

Figure1:

PopulationdensitymapofEurope(adaptedfromAnon2007)

0

Population Density

< 10

10 - 24

25 - 43

44 - 62

63 - 87

88 - 116

117 - 195

> 195

No Data

N

S

EW

200 400 600 800 1000

Kilometers

0

Population Density

< 10

10 - 24

25 - 43

44 - 62

63 - 87

88 - 116

117 - 195

> 195

No Data

N

S

EW

200 400 600 800 1000

Kilometers

organicfarming.Thepotentialoforganicfarmingtofeedtheglobalpopulationhasbeendebatedformanyyears,butarecent,extensiveandauthoritativereview(Badgleyetal.,2007)clearlyindicatesthatitispossible.ThisstudyconsidersEuropeandsuggeststhatitcouldfeeditselfbymeansoforganicfarming.

Currently, how food-secure is Europe? Data are sparse,Currently,how food-secure is Europe?Dataare sparse,but recentassessments inBritain (UKAgriculture,2005)suggestthatnon-organicdomesticproductioncontinuestodeclineandcurrentlyfeedsnomorethan60-73%ofthatpopulation.Thus,totalfoodproductioninEurope,postpeakoiland

naturalgas,maybemuchreducedandcommoditiesmight

H.C. Lee, R. Walker, S. Haneklaus, L. Philips, G. Rahmann and E. Schnug / Landbauforschung - vTI Agriculture and Forestry Research 3 2008 (58):145-152

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Tyneside

Sunderland

Teesside

North and West

York

Blackpool Bumley LeedsBradford Hull

BlackbumPreston Wakefield

Rockdale

HuddersfieldBolton Doncaster

Liverpool GrimsbyWigan Bamsley

ManchesterSheffield

WarringtonBirkenhead

Mansfield South and East

StokeNottingham

Derby

Norwich

Telford Leicester

PeterboroughBirmingham

Coventry NorthamptonCambridge

Ipswich

Luton

Gloucester

Oxford

SouthendSwindon

LondonBristol

Reading

Medway Towns

CrawleyAldershot

Southampton

Portsmouth HastingsWorthing Brighton

Bournemouth

Plymouth

Figure2:

England:primaryurbanareaswithapopulationgreaterthan125,000.(adaptedfromDefra(2006))

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onlybeabletobetransportedrelativelyshortdistancestothe consumer. It follows that food production and con-sumptionwillbecomemoreregionalisedandquiteprobab-ly localised. IfweconsiderthepopulationdistributionofEuropeannations(Figure1),itcanbeseenthatthespreadisheterogeneous.Forexample,inEngland(Figure2),mostpeopleliveclosetourbancentresofpopulation.

Rural and urban issues

Inapostpeakoilscenario,theproblemofaccesstofoodin ruralareasseems likely tobe lesschallenging,duetolowerpopulationpressures.Rather,thekeyissuemaybehowitwillbepossibletofeedhigherdensitiesofpeopleinurbancentres.TheFoodandAgricultureOrganisationhasundertaken a reviewof European urban and peri-urbanfoodproduction,buttheemphasisisuponthehealthben-efitsofavegetable-focusseddietratherthanfoodsecurity(FAO2001).However,muchcanbelearnedfromexperi-encesofurbanandperi-urbanorganicfoodproductioninCuba,whereyieldsashighas2.5kgvegetablespersquaremetre per month have been achieved (Viljoen&Howe,2005),thoughwithinamorefavourableclimatethanthatlikelytobeseenacrossEurope.

The hypotheses of this paper

It issuggestedthatorganicfarmmanagementmightbeidentifiedwith:(i)increasedresiliencetoEWEs, (ii)relative-lylowerconsumptionoffossilfuelsperunitofyield,and;(iii)enhancedfuturefoodsecurityforEurope,especiallyinurbancentres.

Proposed actions: pilot demonstration farms

Totestthesehypotheses,itisproposedthatastudybeinstituted across Europe, involving a comparison ofwa-tershedsthatareprimarilyfarmedorganicallywiththosethatarefarmednon-organically.Thisisnotaspotentiallyexpensiveasitmightseem:watershedsdominatedbyor-ganicfarmsalreadyexistinpartsofGermany(Schnugetal.,2004)andalsoinBritain,asindicatedinFigure3.Suchacomparisonwillneedtoinvolveatleastseveralyearsofauditsof randomlychosenfarmswithineachwatershedfor:fossilenergyconsumption(directandindirect)andef-ficiencyofuse,soilcharacteristics,cropyields,andwaterdynamics.It is also suggested that the potential of organic pro-

duction to feed urban areas needs to be explored. TestsitesneedtobeestablishedinandaroundEuropeancities,toestablishmaximumsustainableyieldsusingtheCubanmodelasabenchmarkbutalsobenefitingfromexistingprojectexperienceinEuropeasdocumentedbyFAO.

Figure3:

UKmapoforganicholdings2004(adaptedfromDefra(2006))

Conclusions

Furtherurgentresearchisneededtoanswerthefollow-ingquestions:canorganicfarmingsystemsreallyleadthewayinadaptingagriculturetothehazardsofamoreun-stable climate?Can organic farms be developed,whichuseminimalorevennofossilenergyinputs(includingen-ginefossilfuels)andyetsustainyields?Dourbanandperi-urbanorganicproductionsystemsholdthekeytosecureandsustainablefoodsuppliesinEuropeancities?Itissug-gestedthatabaseofknowledgeandexperienceneedstobegeneratedasanutmostpriority,beforethefulleffectsofpeakoilandnaturalgasarefeltandshortagesoffoodbecomearealityin21stCenturyEurope.

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