Evaluation of the Dutch implementation of the nitrates directive, the water framework directive and the national emission ceilings directive

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Hans

J.M.

Van

Grinsven

a,∗

_,

_Aaldrik

_Tiktak

a

_,

_Carin

_W.

_Rougoor

b

a_PBL_Netherlands_{Environmental}_Assessment_Agency,_PO_BOX_30314,₂₅₀₀_GH_The_Hague,_The_Netherlands b_CLM_Research_and_Advice,_PO_BOX_62,₄₁₀₀_AB_Culemborg,_The_Netherlands

a

r

t

i

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l

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f

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Articlehistory:

Received9November2015

Receivedinrevisedform20February2016 Accepted17March2016

Availableonline22March2016 Keywords:

Nutrientpolicies Targetachievement Costsandbeneﬁts Nitrogen Phosphorus Surfacewater Groundwater

a

b

s

t

r

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c

t

DutchnutrientpoliciesforagriculturearegenerallyimplementationsofEuropeanenvironmental Direc-tives,i.e.theNitratesDirective(ND),theWaterFrameworkDirective(WFD)andtheNationalEmission CeilingsDirective(NECD).Wepresentanevaluationofthesepolicieswithrespecttotarget achieve-ment,effectiveness,costsandbenefits.ImplementationoftheNitratesDirectivedecreasednutrient surplusesandimprovedgroundwaterquality.However,thenitratetargetof50mg/lwasstillexceeded ingroundwaterinhalfofthesandregion.Ecologicalqualityofsurfacewatersimprovedslightly,but thisimprovementwasmainlyduetomeasuresfortheWFDandnottoreducednutrientlossesfrom agriculture.TheNECDreducedemissionsofammoniaeffectively,butcriticalloadsofnitrogenwere stillexceededinthemajorityofecosystems.Healthbenefitsofreducingtheconcentrationsof ammo-niaaerosolswerehoweversubstantial.Overall,nutrientpolicieshavegeneratednetbenefitsforDutch society:Annualcostswereestimatedtobe500millioneurosandsocietalbenefitswereestimatedto bebetween900and3700millioneuros.Withpoliciescurrentlyinplace,thegeneralprotectiongoals oftheDirectiveswillnotbemet.Reachingmoretargetsinacost-effectivewaywouldfirstrequire bet-tercoordinationofpoliciestoimplementthethreeDirectives.Forexample65%ofphosphorusinputto surfacewatersiscausedbyagriculturebuttheDutchimplementationoftheWFDhardlycontainsany measurestoreducenutrientloadsfromagriculturalsoils.Inadditiontomorestrictnationalpolicies thatarebetterenforced,regionallydifferentiatedmitigationoptionswouldbeneeded.Themostrobust optionwouldbeminingofsoilphosphorusbyzeroP-applicationinagriculturalsoilsthataffectsensitive aquaticecosystems.Wheretargetachievementcannotbecombinedwithcompetitiveagriculture, polit-icalchoiceswouldhavetobemadebetweenecologyandagriculture,orforfinancialcompensationof affectedfarmers.Akeyfactorforimplementationwouldberedistributingofcostsandbenefitsbetween specificgroupsoffarmersorregions.ThiswouldimplybetterintegrationoftheCommonAgricultural Policywithenvironmentaldirectives.

Contents

1. Introduction...70

2. Materialsandmethods...70

3. Environmentallegislation...71

3.1. Europeanlegislation ... 71

Abbreviations:CAP,CommonAgriculturalPolicy;EC,EuropeanCommission;EQR,EcologicalQualityRatio;FADN,FarmAccountancyDataNetwork;ND,NitratesDirective; IHW,InformationHouseWater;LMM,MineralsPolicyMonitoringProgramme;MINAS,MineralAccountingSystem;MNLSO,MonitoringProgrammeforSurfaceWaters PredominantlyAffectedbyAgriculture;NECD,NationalEmissionsCeilingDirective;PRTR,DutchPollutantReleaseandTransferRegister;RBMP,RiverBasinManagement Plan;WFD,WaterFrameworkDirective;WTP,WillingnesstoPay.

∗Correspondingauthor.

E-mailaddress:[email protected](H.J.M.VanGrinsven). http://dx.doi.org/10.1016/j.njas.2016.03.010

1573-5214/©2016TheAuthors.PublishedbyElsevierB.V.onbehalfofRoyalNetherlandsSocietyforAgriculturalSciences.ThisisanopenaccessarticleundertheCC BY-NC-NDlicense(http://creativecommons.org/licenses/by-nc-nd/4.0/).

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3.2. Thenitratesdirective...71

3.3. Thewaterframeworkdirective(WFD)...72

3.4. Thenationalemissionsceiling(NEC)directive...72

3.5. Overlap,synergyandtrade-offsbetweenEUnutrientdirectives...72

3.5.1. RelationbetweenthenitratesdirectiveandtheNECD-NH3...73

3.5.2. RelationbetweenthenitratesdirectiveandtheWFD...73

3.6. FertiliserandmanurepoliciesintheNetherlands...73

3.6.1. Implementationofthenitratesdirective...73

3.6.2. Implementationofthewaterframeworkdirective...74

3.6.3. ImplementationoftheNECdirectiveforammonia ... 75

4. Resultsanddiscussion...75

4.1. Evaluationofachievementofspeciﬁcenvironmentalobjectives...75

4.1.1. Nutrientinputsandsurpluses ... 75

4.1.2. Groundwater...75

4.1.3. Surfacewater...76

4.1.4. Ammoniaemission...76

4.1.5. Compliancewithmanureregulations ... 77

4.1.6. Interactionbetweeneffectsofpoliciesandpollutionswapping...78

4.2. Achievementofgeneralprotectiongoals...78

4.2.1. Aquaticecosystems ... 78

4.2.2. Terrestrialecosystems ... 78

4.2.3. Humanhealthimpactsofnitrateindrinkingwater...79

4.2.4. Humanhealthimpactsofammoniainair...79

4.3. Costsandbeneﬁts...80

4.3.1. Coststocomplywithfertiliserandmanurepolicies ... 80

4.3.2. Beneﬁtsofnutrientpolicies...80

4.4. Prospectsfortargetachievement...80

5. Optionsforpoliciestoimprovetargetachievement...81

6. Conclusions...82

Acknowledgements ... 82

References...82

1. Introduction

Dutchpolicies toreduce losses of nitrogen and phosphorus fromagriculturetotheenvironmenthavebeeninplaceforthree decades.Thesepoliciesaregenerallyimplementationsofcommon directivesinstigatedbytheEuropeanCommission(EC).In1991 theNitratesDirectivetoreducenitrateemissionsfromagriculture wasacceptedfollowedin2000bytheWaterFramework Direc-tive(WFD),whichaimsatagoodecologicalstatusofwatersand,in 2001,theECNationalCeilingsdirective(NECD)toreduceammonia emissions[1].Nationalimplementationofthesedirectivesinthe Netherlandshalvedthesurplusofnitrogensinceitspeakof250kg perhectareindemid-1990sandconsiderablyreducedthe con-centrationofnitrateingroundwater.However,exceedanceofthe 50mg/lNO3targetinshallowgroundwaterunderagriculturalland

inthesandregionsandexceedanceofecologicalNandPthresholds inlakesandstreamsisstillcommon.Thisraisesquestionsabout theeffectivenessandthecostsandbeneﬁtsofcurrentpoliciesand theproportionalityofadditionalpoliciesandmeasurestotackle remainingpollutionimpacts,relativetotrade-offstoagricultural productionandcompetitivenessoffarms.

The25thanniversaryoftheNitratesDirective(ND)couldbea goodopportunitytoevaluatetheachievementsoftheNDandof nutrientpoliciesingeneral.Theobjectiveofthisarticleisto eval-uatetheachievementofgoals,effectivenessandefﬁciencyofthe Dutchimplementationofnutrientpoliciesforagriculture,forwhich therelevantquestionsare:

•TowhatextentdidtheNetherlandsachievethespeciﬁc objec-tivesandthegeneralprotectiongoalsofnutrientpolicies? •Whatistheeffectivenessofthesepolicies? Howstrongisthe

relationwiththeeffectsonnutrientsconcentrationsinwaterand airandtheirimpactsonecosystemsandhumanhealth? •Whatarethesocietalcostsandbeneﬁtsofthesepolicies?

•Whataretheprospectsofmeetingthegeneralprotection objec-tives of the directives in the future, taking into account the effectivenessandcostsandbeneﬁtsofcurrentpolicies?

We focus on fertiliser and manure policies in the period 1990–2012takingintoaccount linkageswiththeWFD andthe NECDforammonia(NECD-NH3)andthebroadercontextof

aspi-rationsfor sustainableagriculture.Thisevaluation mayprovide usefulinsightsforfutureimplementationsoftheNDandimproved linkagewiththeWFDandNECD-NH3.Thispaperisbasedon

previ-ousevaluationsoftheDutchfertiliserandmanurepoliciesbyRefs. [2–6].Further,theDutchexperiencecanbeinstructiveforotherEU regionswithhighlivestockdensitieslikeDenmark,Flanders, Brit-tany,Catalu ˜na,thePovalleyandtheNorthernpartofGermanyand Poland.

2. Materialsandmethods

ResultsaremainlybasedonWillemsetal.[6]andtheunderlying detailedreportsfortheformalevaluationoftheDutchfertiliserand manureregulation.Prospectsforfuturetargetachievementwere takenfromascenariostudybyVanGaalenetal.[7]andunderlying reports.Thefollowingprimarydatasourceswereused:

•TheFarmAccountancyDataNetwork(FADN)[8],whichcontains dataontheuseoffertilisersandmanure,measuresandnutrient budgetsatthefarmlevel;

•TheMinerals PolicyMonitoringProgramme (LMM)[8,9].This programmemeasuresthenitrateandphosphateconcentrations inshallowgroundwateranddrainwater on437farms.These farmswereselectedusingastratiﬁedsamplesothatfarmswere evenlydistributedamongstregions,farmtypesandfarmsize; •Themonitoringprogrammeforsurfacewatersdominantly

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Fig.1. Goals,objectivesandinstrumentsofthedifferentDirectivesrelatedtocontrolofnutrientloadsfrommanureandfertiliser.

•The Limnodata Neerlandica and Informatiehuis Water (IHW) databases,whichcontainmonitoringdataforNandPinditches, lakesandstreams[11];

•TheDutchPollutantReleaseandTransferRegister(PRTR;www. emissieregistratie.nl),whichcontainsdataonemissionsof indus-trialandagriculturalemissions.

ThecalculationoftheeconomicvalueofreducedN-pollution wasbased onRef. [12] usingstandard economic concepts and methodsforvaluationofhealthimpactsortorestoreorprotect ecosystems.

DatainﬁguresweretakenfromtheDutchEnvironmentalData Compendium(www.clo.nl)unlessstatedotherwise.

3. Environmentallegislation

3.1. Europeanlegislation

Nationalpoliciestoreducenutrientlossestotheenvironment aregenerallyimplementationsofEuropeandirectives.Most nutri-entrelatedEU-directiveswereadoptedinthe1980sand1990sand typicallyaddressemissionsofspecificcompoundsfromindividual sectors,liketraffic,wastewaterandagriculture[2].Thisapproach wasnecessarytoreducecomplexityoftheissuesandnegotiations, butalsocreatesriskofinefficiency(Section3.5).Themost impor-tantEuropeandirectivesaredescribedhereafter.

Inenvironmentalregulationsvarioustermsareusedtoexpress thepurposeoftheregulationandthelegalrequirementfor coun-tries,enterprisesorpersonstosatisfytheseregulations.Wewill usethreeterms(basedonRef.[13]):

•Environmentalgoal:thisisthegeneralprotectiongoalandthe relevantpurposeoftheregulationforsociety,ofteninthefuture, e.g.safewaterforeverycitizen;

•Environmentalobjective:thisisamorespeciﬁcprotectiongoal andoftenanofﬁciallyagreedquantitativepurpose,butstillat anabstractionlevelthatisrelevantandunderstandabletothe

generalpublic,e.g.halvingthenutrientloadtocoastalseasin someyearrelativetoareferenceyear;

•Environmentaltarget: anobjectivethat isexactlyspecifiedin technicalterms:e.g.atargetconcentrationforaspecific com-ponentinaspecificcompartment.

3.2. Thenitratesdirective

The formal objective of the ND (EC, 1991) [14] is reducing water pollutioncaused orinducedby nitratesfromagricultural sourcesandpreventingfurthersuchpollution,againstthe over-archingenvironmentalgoaltoprotectdrinkingwater resources andaquaticecosystemsbyreducingwaterpollutionwithnitrates fromagriculturalsources(Fig.1).TheNDwasacceptedin1991and thefirstnationalactionprogrammewasimplementedinthelate 1990s.TheintroductionoftheNDwasaresponsetothe recog-nitioninthe1980sthattheincreaseduseofmanurefromafast growinglivestocksectorhadnegativeeffectsonwaterqualityand ecosystems.Applicationoflargevolumesofslurrytoboth grass-landandarable landledtoeutrophicationoflakesandstreams fedbyrunoffandleaching.Hoodaetal.[15]attributedthisimpact tothemovefrommixedarable-livestockfarmingtowardsgreater specialisation,togetherwiththegeneralintensificationof agricul-tural production.In theNetherlands highlandprices enhanced intensification[16].

Asaﬁrststepofimplementationmemberstateswereaskedto identifywaterbodiesthatwereeutrophic,orthatwereatriskto becomeeutrophicinthefuture.Allknownareasoflandthatdrain intothesewatershadtobedesignatedasNitrateVulnerableZones. LandandwaterarestronglyinterconnectedintheNetherlandsand thereforetheNetherlandsdesignateditsentireterritoryasNitrate VulnerableZone.Measureshadtobeformulatedinnationalaction programmesforallNitrateVulnerableZoneswherethenitrate con-centrationinsurfaceand/orgroundwaterexceededthetargetof 50mg/lforuseasadrinkingwaterresource,orwherefreshand marinewaterswereeutrophicoratriskofbecomingeutrophic.

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Fig.2.HierarchyofindicatorsfortheobjectivesandgoalsofthedifferentDirectives(basedonRef.[3]).

TheNDincludesrulesfortheuseofanimalmanureandchemical fertilisers.Akeymeasureisthatmemberstatesshouldguarantee thatannualapplicationofNbyanimalmanureatthefarmlevel doesnotexceed170kg/ha.Ahigherratemaybeallowedwhenit canbedemonstratedthattheobjectivesoftheDirectivewillstill berealised.

3.3. Thewaterframeworkdirective(WFD)

TheenvironmentalgoaloftheWFDistoestablishagoodstatus ofallsurfacewatersbytheyear2015[17].Forsurfacewaters,the goodstatuscomprisesagoodchemicalstatusandagoodecological status.Goodchemicalstatusrequiresthatcertainsubstancesdonot exceedathresholdconcentration.Goodecologicalstatusdemands thattheassemblageofalgae,ﬁsh,waterplantsandmacrofauna shouldonly“slightlydeviate”fromacertainreference,whichisthe statusexpectedinpristinewatersofthesametype.TheWFD fur-therrequiresthatnutrientconcentrationsdonotexceedthelevels establishedsoastoensurethefunctioningoftheecosystemandthe achievementofthevaluesspeciﬁedaboveforthebiologicalquality elements.

ImplementationofmeasuresfortheWFDstartedin2009when memberstateswererequiredtodesignriverbasinmanagement plans(RBMPs).Thegoals,objectivesandmeasuresoftheWFD over-lapwiththoseoftheND,particularlyaftertheintroductionofthe GroundwaterDirectivein2006,whichspeciﬁesthegroundwater qualitytargetsforNandP.Phosphorusisoftenthelimiting nutri-entinstagnantfreshwatersandtheprimecauseofblooms,but therearealsomanysystemsthatarenitrogenlimitedorwhere bothnutrientsarelimiting.Restorationofagoodecologicalstatus thereforegenerallyrequiresreductionofbothNandP[18–20].

3.4. Thenationalemissionsceiling(NEC)directive

TheenvironmentalgoaloftheNECDirective[21]istoprotect theenvironmentandhumanhealthagainstpollutantsresponsible

foracidiﬁcation,eutrophicationandground-levelozonepollution (sulphurdioxide,nitrogenoxides,volatileorganiccompoundsand ammonia).ForthistheNECDsetsceilingsforeachmemberstate forthetotalemissionsofthefourpollutants.Ceilingsaresetfor speciﬁedperiods,providingastepwiseapproachtomeetthe over-arching environmentalgoals for EU air quality policies.In this paperweonlydiscustheNECDforammonia(NECD-NH3).Possible

measurestoreduceammoniaemissionsfromagriculturalsources arelaid downinanadvisorycode ofgood agriculturalpractice (AnnexIXofGothenburgProtocolECE/EB.AIR/WG.5/2011/3; see Ref.[22] fora summary).Largelivestockoperationsmust com-plywiththeIndustrial EmissionsDirective[23],which requires these operations to apply best available techniques to control emissions.

3.5. Overlap,synergyandtrade-offsbetweenEUnutrient directives

AgeneralobjectiveofEUenvironmentaldirectivesistohaltthe increaseofpollutionandtoreversetrendstoeventuallyachieve theﬁnalgoalofmaximumprotectionofecosystemsandhumans atproportionalcostsforsociety.Goals,objectives,targetsand mea-suresoftheND,NECD-NH3andWFDareclearlylinked(Fig.2).The

instrumentalpolicyapproachis,however,different.TheNDisa ‘means-orientedregulation’,prescribingamixofcompulsoryand voluntarymeasuresandinstruments.TheWFDisgoal-oriented; memberstatesmustensurethatgoodecologicalstatusofall sur-facewatersisreachedby2027buthavemorefreedomtochoose andplantheirmeasures.TheNECD-NH3directivetakesan

inter-mediateposition,whereceilingsandrecommendedmeasuresare ameanstoimproveachievementofenvironmentalgoals. Further-more,measuresfortheWFD areoftenregionally differentiated, while those for the ND and the NECD are more generic with applicationstandardsfordifferentcropsandsoilsintheND,and recommended NH3 reduction measures for livestocktypes and

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Fig.3. InstrumentsoftheDutchmanureandfertiliseractinrelationtoinstrumentscontrollingagriculturalemissionofnutrientsinotherpolicies,theireffectonnational policyobjectivesandthegoalsofEUdirectives.1)mandatorylowemissionapplicationofmanureispartofthesoilprotectionactandcontributestoobjectivesofboththe NDandtheNECD.2)ManurefreezonesarebothrequiredforimplementationoftheNDandWFD.Dashedarrowsindicatepotentialco-beneﬁtsofpolicies.

3.5.1. RelationbetweenthenitratesdirectiveandtheNECD-NH3

ThecontributionofnitrogendepositiontothetotalNinputof freshwateraquaticecosystemsisapproximately20–25%[12]both intheNetherlandsandonaverageintheEU.Ammoniaemissions fromagricultureareamajorsourceforNdeposition.Thiscreates arelationbetweenimplementationsoftheNDandtheNECD-NH3.

ApossibleconﬂictbetweentheimplementationoftheNDandthe NECD-NH3isthatmeasurestoreduceammonialossesfrom

hous-ing,storageandduringapplicationofmanurewillincreasetheN contentinmanureandbythatincreaseNsurplusesandenhance nitrateleaching,ifnotaccompaniedbyanoverallreductionofN inputsoradditionalmeasures[1].Ontheotherhandapplication restrictionsformanurewillleadtoamore evendistributionof manureNonagriculturalland,whichmaypromoteemissionof ammonia.

3.5.2. RelationbetweenthenitratesdirectiveandtheWFD

TheintroductionoftheWFDin2000alsocreatedsynergiesand trade-offs.AmajorgoaloftheWFDisrestorationofagood ecologi-calstatusinallwaters,whichincludesthegoaloftheNDtoprotect wateragainsteutrophication(Fig.1).Thereare,however,two pos-sibleconﬂictsbetweentheWFDandtheND,i.e.(i)forachieving agoodecologicalstatusalowerNconcentrationof0.9–5.0mg/lis neededthanthetargetthatisusedintheND(11.3mg/l)and(ii)the NDdoesnotaddressothersourcesofnutrientssuchas wastewa-tertreatmentplants.Forthesereasons,theEuropeanCommission increasinglysuggestsastrongerlinkagebetweenimplementation oftheNDandWFD,forexamplebyusingwaterpricingfor agri-cultureasafutureelementofgreeningtheCommonAgricultural Policy[24,25].

3.6. FertiliserandmanurepoliciesintheNetherlands

Since1984nationalmeasureshavebeentakentoreducethe environmentalimpactofmanureandfertilisers.ThecurrentDutch approachisacombinationofmeasurestocontroltheproductionof manureandmeasurestoreducetheloadstosoilsandwater(Fig.3). Since1991theManureandFertiliserActbasicallyisthenational implementationoftheND.

3.6.1. Implementationofthenitratesdirective

TheNetherlandshassuccessfullyappliedforanallowanceofN inputsfrommanuretoamaximumof250kgperha(‘derogation’) ondairy farmswhereatleast70%oflandisinuseasgrassland [26].ThisderogationappliestoalmosthalfoftheDutchagricultural landandisthemostextensivederogationintheEU[27].Inviewof insufﬁcientimprovementofwaterquality,theEuropean Commis-sionlimitedthisderogationfrom2015onwardsbyincreasingthe requiredpercentageoflandinuseasgrasslandto80%and reduc-ingthemaximummanureNinputto230kg/haforsandandloess regionsinthecentreandsoutheastoftheNetherlands.

Currently,thecoreoftheManureandFertiliserActisasystem ofsoilandcropspeciﬁcapplicationstandardsforNandP.Tomeet theenvironmental targetsof theND,the applicationstandards weregraduallyloweredsinceitsintroductionin2006(Table1). TheDutchapplicationstandardsincludestatutoryfertiliser equiv-alenciesforNinmanure,whicharerelativelystrictcomparedto otherEUmemberstates[27].Therefore,statutory equivalencies wereincreasedformanureNongrazedgrassland (from35%in 2006to45%since 2009), forpigslurryN onsandyarableland (from60%in2006to80%since2014)andforcattleslurry(from

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Fig.4.Nationalexcretionandfertiliseruseofnitrogenandphosphate.

Table1

Applicationstandardsfortotal(fertiliserpluseffectivemanure)nitrogenand phos-phatein2006,2009and2015(inkgNandkgP2O5/ha)forgrassand(asanexample)

forwarepotatoes.

2006 2009 2015

Ngrassa _290–385 _260–340 _250–385

Nwarepotatoesb _240–300 _225–275 _210–275

P2O5grass 110 100 80–100c

P2O5crops 85(+10)d 85 50–75c

a_Range_caused_by_{differentiating}_between_grazing,_mowing_and_between_soil

type.

b _Range_caused_by_{differentiating}_between_soil_types.

c _Range_caused_by_{differentiating}_between_different_phosphate_statuses_of_the

soil.

d _An_additional₁₀_kg/ha_P_may_be_given_as_mineral_fertiliser.

45%in2006to60%since2010).Thecurrentsystemreplacedthe mineralaccountingsystem(MINAS),whichaimedatachieving bal-ancedfertilisationatthefarmlevelbysettingasmallsetofNandP lossstandards.However,theEUcourtofJusticejudgedthatMINAS wasnotacorrectimplementationoftheND,becauseitimplicitly allowedexceedanceofthelegalEUlimitvalueof170kg/haNin manureandbecauseitwasaretrospectivecheckratherthanana prioricontrolsystematthestartoftheseason[3,28].This under-linesadrawbackof theinstrumental approachoftheNDbeing ameans-orienteddirectiveratherthanagoal-orienteddirective (Section3.5).

Tocontrolproductionofmanure,asystemoftradablemanure production quota was introduced for pigs (1998) and poultry (2001).Thissystemincludedregionalbarriers,buying-upschemes andcompulsoryskimmingforeverytradeevent(until2002).The productionquotareducedtheexcretionofPby15%between2000 and2003[4].However,theambitionoftheDutchparliamentis toabolish thissystembytheyear2017,when thecurrentﬁfth ActionProgramme ends. Onereason for abolishment is that in April2015themilkquotasystemfordairyended.Maintaininga quotasystemforpigs andpoultrycouldcreateanimbalancein competivenesswiththedairysectorwhencompetingfordisposal contractofsurplusmanuretoarablefarmers.Notethatunlikethe productionquotaforpigsandpoultry,themilkquotasystemof 1984isnotanutrientpolicy;however,itlimitedmanure produc-tionindirectly.Inresponsetothefastgrowthofthedairysectorin anticipationoftheabolishmentofthemilkquotasystem,theDutch governmentannounced newpoliciesin 2014and 2015 to pre-ventintensiﬁcationandmanuredisposalproblemsfordairyfarms andtoslowdowntheincreaseofthePexcretion.Thelatterwas

necessarytoavoidtheriskofexceedanceofthenationalP excre-tionceiling,whichisaconditionformaintainingthederogation [27].

Givenatrendtostricterapplicationstandards(Table1)thereis anincreasingriskthatnationalorregionalproductionofmanure exceedsthecapacityofagriculturallandtoadsorbtheassociated amountofNandP.Therefore,since2014theNetherlandshasa pol-icyforcompulsorymanureprocessingforafractionofthemanure surplusatthefarmlevel.FortheSouthoftheNetherlandsthis frac-tionincreasedfrom30%in2014–55%in2016,fortheEastfrom15% to35%, and forother partsof theNetherlands from5% to10% (https://www.rijksoverheid.nl/documenten/kamerstukken/2015/ 12/10/kamerbrief-over-percentages-verplichte-mestverwerking-2016).Manureprocessingwill increasethecostof manure dis-posal,butimprovesexportabilityofmanureproducts.Further,the feedindustry isdevelopingcovenantswithlivestockfarmingto reducemanureandPexcretionbyreducingthePandproteinin compoundfeed.

3.6.2. Implementationofthewaterframeworkdirective

TheWFDhastheoptionforphasingtargetachievementuntil theyear 2027 and theDutch governmentapplied this exemp-tionto86%ofDutchsurfacewaterbodies.Theyarguedthatfully achievingtheWFDobjectivesby2015wouldnotbepossibleand wouldalsonotbepragmatic,feasibleoraffordable.Measuresfor theWFDaredescribedinRiverBasinManagementPlans(RBMPs). ThefocusintheDutchRBMPsisonmeasuresimprovingthe hydro-morphological status of surface waters. The ratio betweenthe actuallyobservedecologicalqualityandthereferenceiscalledthe EcologicalQualityRatio(EQR),IntheNetherlands,thetargetvalue forgoodecologicalstatushasbeensetto0.6[29].Notethatthe targetvaluediffersbetweenmemberstatesandisoftennotbased onthresholdsrelevanttotheecosystem[30].IntheNetherlands mostwaterbodiesareclassifiedasheavilymodifiedorartificial. Forthesewaterbodies,alowertargetvaluemaybedefined.

TheformalDutchinterpretationintheﬁfthActionPlanforthe ND is that this ActionPlan is partof theWFD programmes of measuresand musthelptoensurethat emissionsfrom agricul-turalsourcesdonotstandinthewayofWFDgoals.Further,an amendmentin2007byDutchparliamenthasruledthatadditional measurestoreducepollutionbynutrientsfromagriculturalsources maynot increase thetotal cost offarmers for takingmeasures requiredfortheND.Hence,theonlynutrientrelatedmeasurein theﬁrstgenerationofRBMPswasabanonfertiliserandmanure applicationclosetowaterbodieswithahighnaturevalue.

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Fig.5. FarmlevelsoilNandP2O5surplussesforthedairysectorandforthearablesector.

3.6.3. ImplementationoftheNECdirectiveforammonia

Legalregulationsfor reduction of ammoniaemission during manureapplicationwerealready introducedin1991toprotect ecosystemsfromeffectsofacidiﬁcationandNdeposition. Regula-tionstoreduceemissionsfrommanurestorageandhousingwere graduallyintroducedsince1994andemissionsstandardsper live-stockunittoachievetheEUNECD-NH3emissionsceilingscame

intoeffectin2008.Theceilingfortheperiod2010–2019is128 ktonNH3andnewceilingarecurrentlynegotiatedfortheperiod

2020–2024at13%,andfortheperiod2025–2029at25%belowthe emissionlevelof2005[31].

4. Resultsanddiscussion

4.1. Evaluationofachievementofspeciﬁcenvironmental objectives

4.1.1. Nutrientinputsandsurpluses

Thetotalconsumptionofnitrogenfertiliserhasdecreasedby 50%since 1990andthat ofphosphatefertiliserby 85%(Fig.4). Nationalanimalexcretiondecreasedby40%forbothnitrogenand phosphate.Inthefollowingsectionwewillexplorethecausesand consequencesofthislargereductionofNandPinputs.

Improvementofgroundwaterandsurfacewaterqualityby cur-rentfertiliserandmanurepolicyisprimarilydeterminedbythe gradualloweringofapplicationstandardsfortotalNandP(Table1). Themaineffectofloweringthesestandardsisadecreaseoftotal inputtothesoilandadecreaseoftherelativeproportionof syn-theticfertiliserintotalNandPinput.Asaresultthephosphate inputsonagriculturallandnowalmostcompletelyrelyonuseofP inmanure,andsoonnationalimportsofphosphateinfeed.

Thesurplusofnitrogenandphosphateinthesoilbalanceisan indicatoroftheefﬁciencybywhichthemineralsappliedaretaken upbycropsandbythatofthepotentiallossestotheenvironment. Sincethestartofthemanureandfertiliserpolicyboththenitrogen andthephosphatesurplusesinthesoilbalancehavedecreased. Phosphatesurpluseshavedecreasedmorestronglythannitrogen surpluses(Fig.5).Themajorcauseisthereductionoftheuseof phosphatefertiliser,whichdecreasedfrom75millionkilogramin 1990–10millionkilogramsin 2014(Fig.4).Reducedinputsand improvedmanagementofnitrogenindairyfarmingaremajor rea-sonsforastrongdecreaseoftheNsurplusinthelate1990s,while Nsurplusesinarablefarminghardlydecreased.

4.1.2. Groundwater

Nitrate. Thenitrateconcentrationsinshallowgroundwaterhave decreased since 1992 in all regions (Fig. 6). Concentrations

Fig.6.Nitrateintheuppergroundwaterinagriculturalareasforthetotaland south-easternsandregionandfortheclayregion.

decreasedmoststronglyintheﬁrstdecadeofadoptionoftheND duetothecombinedeffectofimprovedawarenessoffarmersand regulationslaiddowninMINAS.Commonunderstandingisthat particularlydairyfarmersbecameawarethatthetotalNapplied asmanureandsyntheticfertiliserbyfarexceededplantdemand. Thisstimulatedfarmerstoreducechemicalfertiliserinputsbeyond legalrequirementsyet[5].Sothedecreaseofnitratebefore2005 wasbothadirectandindirecteffectoflegislation,withlowﬁnancial costforfarmers.

In the clay region the mean nitrate concentration doesnot exceedthetargetvaluesince2005.However,inthesandregion theaveragevalueisabovethetargetvalue,especiallyinthe south-ernpartoftheNetherlands(Fig.6).Thiswasthemajorreasonthat in2014thederogationfordairyfarminginthesandregioninthe southoftheNetherlandswasloweredfrom250to230kg/haNin manureandthestatutoryfertiliserequivalencyforpigmanurewas increasedfrom70%to80%.Thesandregionishighlyrelevant;it coversnearlyhalfofthetotalagriculturalareaofthecountry.In 2012morethanhalfofthedairyfarmsinthesandyregion com-pliedwiththenitrate-Ntargetof50mg/lofnitratebutlessthana quarterofthearableandintensivelivestockfarmsdid(Table2).

Whenconcentrationsarecorrectedfordifferencesin precipita-tionbetweenyears,thereisastrongcorrelation(Fig.7,R2₌_0.82)

between the decrease of the nitrate concentration in shallow groundwaterinthesandregionandthedecreaseoftheNsurplus, particularlyondairyfarms[32].Onaverage,thenitrate concen-trationdecreasesby 0.6mg/lper kilogramof decreaseoftheN surplus.Thisindicatesthatreductionofnitrogensurpluslikelyisan

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Table2

Area,averagenitrateconcentrationandpercentageoffarmsbelowthetargetvalueof50mg/lorlessduringtheperiod2007–2010inthesandregion(source:Willemsetal. [6]).

Area(percentageofsandregion) Averagenitrateconcentration(mg/l) Percentageoffarmsbelowtargetvalue(50mg/l)

Dairyfarms 47.5% 51 55%

Arablefarms 16.2% 78 21%

Intensivelivestock 5.7% 130 23%

Other 24.2% 70 41%

Fig.7.NitrateconcentrationinthesandregioninshallowgroundwaterandN sur-plusperhectareinthesandregion.Theyearofthenitrateobervationisshifted backwardbyaboutoneyeartomakeitcorrespondtoistheyearofNsurplusthat causedtheleaching[32].

Fig.8.TrendsofP2O5surplusandPconcentrationintheuppergroundwaterinthe

sandregion.ThehighPconcentrationsin1994and1995werecausedby exception-allyhighgroundwatertables.

effective strategy to decrease nitrogen in groundwater. How-ever,thecorrelationseemstodecreaseafter2008.Thecontinued decreaseofnitrateconcentrationscouldbeadelayedresponseto thedecreaseoftheN-surplusbefore2008[33].

Phosphate. Despite the strong decrease of the P surplus

(Figs. 5 and 8), since 1992 the phosphorus concentration in groundwaterdoesnotshowacleartrendovertime(Fig.8).This conﬁrms ﬁndings thatthe Pconcentration ingroundwater is a functionof theP saturationdegree rather thanof the actualP

surplus[33].TheNetherlands is anextremecase regardingthe phosphoruscontent of soils.Chardonand Schoumans [34] and Tóthetal.[35]showedthatmorethan50%ofsoilsamplesfrom theNetherlands(collectedusingstandardisedprocedures)fellin thehighestcategory,indicatingthatnoadditionalPfromfertiliser isneeded.However,thephosphorusinputsperhectarebymanure andfertiliseronagriculturallandintheNetherlandsarestillthe highestvalueswithintheEU[36,37].

4.1.3. Surfacewater

In theperiod1990–2013,agriculturalinputs ofN tosurface watersdecreasedby37%andthoseofPby17%(Fig.9).Inthesame period,nutrientinputsbywastewatertreatmentplantsdecreased by80%duetoimprovedtreatmentefﬁciency.Asaresult,diffuse inputsofNandPfromagriculturewerethedominantsourceof nutrientinputsin2013(approximately60%ofthetotalloadforN andP[7]).Duetovariabilityofprecipitationbetweentheyears, thediffusenutrientloadsinFig.9showconsiderablevariability betweentheyears.Thisimpliesthatlong-termtrendscannotbe establishedbasedondatafromindividualyears.

ThedecreaseofnutrientloadsfromagriculturallandinFig.9is primarilycausedbygenericfertiliserandmanurepolicies.Regional mitigationmeasuresincludedintheWFDandtheND(inparticular fertiliserandmanurefreezones,wetbufferzonesalongstreams andrestricteddrainage)hardlycontributedtothedecreaseof agri-culturalnutrientinputstosurfacewater.Theirpotentialtoreducing nutrientloadsis,however,large:Whenfertiliserandmanurefree zoneswouldbeinstalledalongallwaterbodies,NandPloadsfrom agriculturewouldbereducedbyabout20%[39].Current imple-mentationofbufferzonesonagriculturallandislessthan3%of whatwouldbepossibleandthereforehardlyreducestotalnational nutrientloads.

In2010,Nconcentrationswereonaverage1.5timesabovethe qualitystandard andPconcentrations wereonaverage3times abovethequalitystandard(Fig.10).Nitrateconcentrationsinfresh surfacewatersarelowcomparedtootherEuropeancountriesand Dutchrivers are relatively hypertrophic. Dutch lakes are often eutrophic due tohighP levelsand salinewater due toN [40]. Phosphorus showeda strongerdecrease than nitrogen, primar-ilybecauseofimprovedwastewatertreatment.VanderBoltand Schoumans[41]concludedthattheregionalmeanconcentrationof NandPdecreasedmorestronglythantheregionalmedian concen-trationofthesenutrients.Thissuggestsarelativelystrongdecrease ofpeakconcentrations,whichislikelyduetorestrictionson apply-ingmanureoutsidethegrowingseason,onsteepslopes,onfrozen soilsandnearwatercourses.Abouthalfofthesamplingsitesin regionalsurfacewatersystemscompliedwiththeconcentration targetsforeitherNorPinsurfacewaters[7].

4.1.4. Ammoniaemission

Regardingammoniameasures,theeffectofpolicyisreﬂected mostclearly in thenational ammonia emission inventories for varioustypesof manurestorage,livestockhousingand manure applicationtechniques.Theseinventoriesshowthatthe contribu-tionofagriculturalsourcestothenationalammoniaemissionswas 85%.Agriculturalemissionsdecreasedby70%since1990,mainly

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non-correctedNandPloads.

Fig.10.RatioofPandNconcentrationsandtheirrespectivequalitystandards averagedoverallWFDsurfacewaterbodies.

Fig.11.Trendsofemissionsandconcentrationsinambientairofammonia.

duetomandatorylowemissionapplicationofmanuresince1991 (Fig.11).Thecontributionofemissionfromsyntheticfertiliserin 2013was13%.Inspiteofthe50%reductionofsyntheticfertiliser use(Fig.4),the2013emissionof13.6ktonNH3wasclosetothe

level in 1990due toa gradual replacement of calcium ammo-niumnitratebyureatypefertiliser.Inthesameperiod,however,

measuredammoniaconcentrationsonlyslightlydecreased.There areseveralexplanationsforthisdiscrepancyoftrends[42].First, thedecreaseofemissionsmighthavebeenoverestimateddueto lackofcompliancewithregulationsforammoniaemissionsfrom housingand duringmanureapplication (Section4.1.5).Second, thenumberofsiteswhereammoniaconcentrationsaremeasured mightbetoolowtocapturethehighspatialvariabilityofammonia concentrationstypicalforagriculturalemissions.Finally,NH3

con-centrationsmayhaveincreasedbecauseofthestrongdecreaseof SO2inresponsetoacidiﬁcationpolicies,whichreducesformation

anddepositionofairborneammoniaaerosols.Huijsmansetal.[43] reconﬁrmedin2015theearlierconclusionthatforgrassland low-emissiontechniqueseffectivelyreducethelossofammoniawhile increasingtheavailabilityofNforgrassproduction.

4.1.5. Compliancewithmanureregulations

Thecurrentmeanannualcostforpigorpoultryfarmerto dis-posetheirmanureis15eurospertonwithseasonalpeaksupto25 eurosperton[44].Thiscanmakemanurefraudaproﬁtablepractice. Allfarmshavetokeepmineralaccounts.Compliancewith applica-tionstandardsiscontrolledforanannualsampleofabout385farms andfocusedonfarmsatriskofviolation.Finesforexceedanceof applicationstandardsarebetween7and11europerkgNorP. Therearebothstatisticalandobservationalindicationsfor viola-tions.Forexample,in2009,15–20%ofintensivelivestockfarms didnotcomplywithlegalrequirementsregardingNorP applica-tionstandards[6].Dataforproductionandexportofmanurebased onfarmaccountstotheauthoritiesindicatethatthelegalspaceto applyNandPfromanimalmanureiscommonlyexceededinthe sandregionsoftheNetherlands(Fig.12).Insomemunicipalities, applicationstandardsareexceededbymorethan35%forPand25% forN.ThiscorrespondstoexceedanceofNapplicationstandards of60–100kg/haandofP2O5applicationstandardsof25–35kg/ha.

However,partofthisexceedancemaybeduetoerrorsin allocat-ingmanureproductionandtransporttospeciﬁcmunicipalities,and notnecessaryistheresultofviolationofregulations.

Anempiricallyestablishedrelationbetweenthenitrate concen-trationinuppergroundwaterandNsurplus(Section4.1.2)implies that theexceedance ofapplication standardscorresponds toan increaseofNO3concentrationsby30–50mg/l.Thiscouldexplain

theobservedexceedanceofthenitratestandardinshallow ground-waterinthesandregionsincludingthesouth(Fig.6).Thissuggests thatstricterenforcementofmanureregulationscanincreasethe effectivenessofmanureandfertiliserpolicies.Overallcompliance offarmswiththemanurepolicieshasincreasedsince2006toalevel ofmorethan90%in2010,buttheeffectofthenon-complianceon theenvironmentisnotclear[6].

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Fig.12.UtilisationofNandPfromanimalmanurerelativetothelegalspaceatmunicipalitylevel(2013).DataarebasedoncensusdataforproductionandnetexportofN andPinmanure(source:CBS-statline).

Therearealsocomplianceproblemswithregulationsfor reduc-tion of ammonia emissions from housing and during manure application.In200811%ofslurryapplicationongrasslandwasnot inaccordancewithregulation.Furthermore,in2012,about75%of mandatoryairscrubbersonanimalhousingforpigsandpoultry didnotmeetlegalrequirements.Shortcomingsincludedabsence ofregisteredairscrubbersandairscrubbersthatwerenotin oper-ationbecausefarmerswantedtosaveenergy.Closersurveillance waseffectiveandin2014only15%ofpigandpoultryfarmswasin violation.

4.1.6. Interactionbetweeneffectsofpoliciesandpollution swapping

ImplementationofDirectivessince1990hasclearlychangedN ﬂowsin agriculture,and insomeoccasionstheactualtimingof changesofthemanureandfertiliserpolicyisreﬂectedintrends (Fig.13).Forexample,theintroductionofproductionquotaforpigs in1998sloweddowntheincreaseofmanureproduction. Further-more,theintroductionofthemineralaccountingsystem(MINAS) in1998resultedinanimmediatedecreaseoftheuseofNfertiliser [3].Therewasalsoanalmostimmediateeffectoftheintroduction ofmandatorylowemissionmanureapplicationin1991on ammo-niaemissions.However,thedrawbackoftheseapplicationrulesis anincreaseofNcontentinmanureandtheapplicationofmanure NsloweddownreductionofNleachingduetoreduceduseof syn-theticNfertiliser(Fig.13;Section3.5).Nitrateleachingdidnotstart todecreaseuntilaftertheintroductionofMINASin1998.

4.2. Achievementofgeneralprotectiongoals

Itisdifﬁculttodeterminetowhatextentthegoalsofthethree Directives regarding humanhealth and ecosystem health have

beenachievedbecausethereis nosimple, univocalrelationship betweenwaterandairchemistryontheonehandandimpactson humanhealthandecosystemhealthontheotherhand. Further-more,ecosystemhealthislesssystematicallymonitoredthanwater andairquality,andhumanhealthimpactscanonlybeinferredfrom epidemiologicalstudies.

4.2.1. Aquaticecosystems

IntheWFD,theoccurrenceoffourspeciesgroups(algae,water plants,ﬁshesandmacrofauna)isusedasanindicatorofecological quality(Section3.3).Ecologicalqualityisevaluatedtobegoodif allindicatorspeciesarepresentintherightamount.Monitoring dataof2013collectedbyregionalwaterboardsindicatesthatthe numberofwaterbodiesthatisevaluatedas“good”wasabout20% forwaterplantsandmacrofaunaandalmost40%forﬁshandalgae (Fig.14).

Only5%ofwaterbodiesscored“good”forallfourspeciesgroups (“one-out,all-out” principle).Thenumber ofwater bodies with agoodbiologicalstatusforoneoftheWFD-groupsincreasedby 4–12%in the period 2009–2013 (Fig. 14). These changes were primarilydue tomeasures improvingthe hydro-morphological qualityof surfacewaters[7].Notice,however, thatpercentages reportedarebasedontargetsforheavilymodiﬁedwaters,usinga lowerreferencequalityascanbefoundinpristineaquatic ecosys-temsofthesametype(Section3.3).

4.2.2. Terrestrialecosystems

Eutrophicationisalsoamajorcauseofdegradationof terres-trialecosystemsand wetlands (Figure15).In theseecosystems nutrientinputismainlybydeposition.In2010thecriticalN depo-sitionwasexceededon75%ofDutchareasprotectedundertheEU BirdsandHabitatDirective[45].Approximately40%ofthetotalN

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Fig.13.TrendofNﬂowsinagricultureintheNetherlands(1990=100)inrelationtothetimingofchangesofnutrientpolicies.

Fig.14.Numberofsurfacewaterbodieswithagoodbiologicalstatusforeachof thebiologicalindicatorsoftheWFD.Awaterbodyisconsideredtobeingoodstatus iftheEcologicalQualityRatio>0.6(seeSection3.3).

depositionisfromagriculturalNH3emissionsandthereforetheNE

C-NH3Directiveisimportanttoreduceexceedanceofcritical

depo-sitionloadsfortheseecosystems.Indeed,more thanhalfofthe decreaseofnitrogendepositionbetween1990and2013wasthe resultofmeasurestoreducetheammoniaemissionfromDutch agriculturesuchasmandatorylowemissionmanureapplication andtheintroductionoflowemissionhousingsystems.

DespitethereductionofNdeposition,thepresenceof charac-teristicplantspeciesandqualityofthehabitatsisstillunfavourable in80%oftheNatura2000areas[46].Thereasonisthattheother stressfactorssuchashabitatfragmentationanddesiccationhave notbeentakenaway[46].

4.2.3. Humanhealthimpactsofnitrateindrinkingwater

ThepercentageofDutchconsumersexposedtodrinkingwater exceedingthelegal EUthreshold valueof 50mg/l is negligible. Morethan99%ofDutchconsumersareconnectedtopublic drink-ingwatersupplyforwhichitisillegaltosupplywaterexceeding thenitratethreshold[47].However,thisthresholdisabovethe no-effectconcentrationforvariouspossiblehealtheffectsofnitrate

Fig.15.Therelativeimportanceofeutrophicationasacauseofdegradationof ecosystemsintheNetherlands(2012).

indrinkingwater,andanitratetargetof25mg/lisprobablymore appropriate[48].VanGrinsvenetal.[47]estimatedthatin2005 about3.5%oftheDutchpopulationwasexposedtodrinkingwater fromgroundwaterresourcesexceeding25mg/l.Theoretically,this exceedancewouldincreasetheincidenceofcoloncancerby100 casesperyear(1%oftotalnewpatients).Inviewofthissmall con-tributiontothetotalincidenceofcoloncancer,itis,however,not possibletoconﬁrmthesetheoreticalnumbersbyempirical evi-dence.

4.2.4. Humanhealthimpactsofammoniainair

Theabsenceofa decreaseofNH3 concentrationssince 2005

(Fig.11)questionstheeffectivenessofammoniameasureswith respecttohumanhealth.Ammoniais,however,alsoaprecursor forsecondaryaerosols,whichisacomponentofpotentially harm-fulparticulatematter(PM).In2005theaveragelifeexpectancyin theNetherlandsduetoPMexposurewasreducedby7–13months, representinganationalwelfarelossof5–25billioneuroperyear [49].Between1992and2013PM10concentrationsdecreasedby about50%inbothurbanandruralareas.ThetrendofPM2.5,which ismorerelevantforhumanhealth,showedasimilartrendasPM10. Secondaryinorganiccomponentsaremainlyaerosolsofammonia, nitrateandsulphateandammoniaaerosolscontributeabouthalfto

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thetotalmassofthe2.5␮mPMfraction[50].Inabsenceof ammo-niatheseaerosolswouldnotbeformed.Asthereisnoevidence thatsecondaryPMislessharmfulthanotherPMcomponents[51], itcanbeinferredthatammoniacontributesalmosthalftothetotal healthimpactofPM.

4.3. Costsandbeneﬁts

4.3.1. Coststocomplywithfertiliserandmanurepolicies

Around2005themeanannualcostfortheagriculturalsectorto complywithfertiliserandmanurepolicieswasapproximately500 millioneuro(Table3).Themajorityofthesecostswasforthe live-stocksectorandconstituted5%ofitsgrossturnoverandabout50% ofitsaddedvalue.Forthedairysectorcostswerepartly compen-satedbyannualsavingsonfertiliserof150millioneuro,butthese savingswereunequallydistributedbetweendifferentfarmtypes andregions.Costsconsistofadministrativecosts(includingthe costsofyearlymineralaccountingbythefarmeroranaccountancy agency),costsformanuredisposalandcostsfore.g.depreciationof investments(Fig.16).Costformanuredisposalincreasedafter2006 byabout70millioneurowhenMINASwithasystemofnutrient lossstandardswasreplacedbyasystemofapplicationstandards (Fig.16).Costincreased particularlyfor intensivedairy farmers whohadtostartdisposingmanuretocomplywiththe applica-tionstandardof250kg/haofNinmanureatfarmlevel.However, administrativecostsdecreasedbecausethesystemofapplication standardswaseasiertoimplementforfarmers.Costsformanure disposalincreasedsomewhatin2011and2012.In2012thetotal grosscost was278millioneuro,of which 44million eurowas acompensationofpigfarmerstoarable farmerstoaccepttheir manure[44].

4.3.2. Beneﬁtsofnutrientpolicies

Van Grinsven et al. [12] estimated the marginal benefits of reducedemissionof NfortheEUbylinkingtheseemissionsto theactualimpactsandtheWillingnesstoPay(WTP)ofpeopleto preventtheseimpacts.Thesemarginalbenefitsareusedhereto estimatethecostsandbenefitsofmanureand fertiliserpolicies intheNetherlands(Table3).Thetotalannualbenefitsforfarmers andsocietyofreducedemissionsofnitrateandammoniaare esti-matedtobe2400millioneurosperyearfortheperiod2000–2008 (Table3).These calculationsare,however, highlyuncertain(its range is 900–3700 million euros per year). The most impor-tantuncertainfactorsare [12,52](i)thedoseresponserelation betweenemissionsandimpacts,(ii)therelative contributionto

Fig.16.Costofimplementationoffertiliserandmanurepoliciesfortheagricultural sector.Costsformanuredisposalarenetcostswhicharecorrectedforpayments oflivestockfarmerstoarablefarmersforacceptanceofmanure.Administrative costsincludecostforfarmerstokeepnutrientaccount,legalcostsand administra-tivecostfortransferoftradablemanurequota.Othercostsincludedepreciationof investmentsinequipmentforstorageandtreatmentofmanure.

theseimpactsofpollutionbyvariousNandPcompounds,and(iii) theWTP.

Despite these uncertainties and not explicitly considering impacts of phosphate pollution, the resultsof this cost-beneﬁt analysisshowthatitislikelythatreducedNpollutionbyDutch fertiliser,manureandammoniapolicieshavegeneratedsubstantial beneﬁtsforsocietybutalsoincreasedproductioncostsforfarmers. Thesecostsareexpectedtoincreaseinthecomingyears,dueto increasingcostsoftransporting,processingandexportingmanure productstocomplywithreducedapplicationstandardsforNandP (Table1)andincreasingmanureproductioninthedairysectordue toabolishmentofthemilkquotasystem.Alsothecostsofadditional measurestoreduceammoniaemissionfromlivestockhousingto complywithloweremissionceilingswillincrease.

4.4. Prospectsfortargetachievement

Inthissectionwepresentanevaluationofcurrentpolicieswith regardtofuturetargetachievement.Focuswillbeontheyear2027, becausethisistheyearthatagoodecologicalstatusofallsurface watersshouldbeachievedtocomplywiththeWFD.

Table3

Annualcostsoffertiliser,manureandammoniapoliciesfortheagriculturalsectorintheNetherlandsaround2005.Nfertilisersavingsarerelativetofertiliserusein2000 andfertiliserpricesin2008.Environmentalbeneﬁtsarebasedonreductionofammoniaandnitratepollutionbetween2000and2008andmonetisationisbasedonWTPto preventimpactsofNpollution.

Annualcosts Millioneuros Annualbeneﬁts Millioneuros

Costsforfarmers Beneﬁtstofarmers

Manuretransport 200(130–250) Fertilisersavings 150

Manureadministration 125(90–170)

Manurestorage 70

Manurelowemissionapplication 60(40–80) HousingNH3reduction 50(15–80)

Yieldreduction 0

Totalcostsforfarmers 505(350–650) Totalbeneﬁtstofarmers 150

Costsforsociety Beneﬁtstosociety

Controlcosts 30 Nrunoffaquaticecosystems 1250(250–2000)

NO3pollutionhumanhealth 10(0–20) NH3pollutionecosystems 300(100–500) NH3pollutionhumanhealth 700(350–1000) Totalcosts(rounded) 530(400–700) Totalbeneﬁts(rounded) 2400(900–3700)

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Modelcalculationsindicatethatthenumberofwater bodies withagoodecologicalstatuscouldincreasefromthecurrent4–12%

to35–50%in2027whentheproposedpackageofWFD-measures

wouldbe fullyimplemented[7]. Theexpectedimprovement in

ecologicalqualitywouldmainlybetheresultofthewidespread implementationofmeasuresimprovingthehydro-morphological conditionsof water bodies, suchastheconstruction of nature-friendlyriverbanksand ﬁshladders,and there-meanderingof streams.Toreachagoodecologicalstatusinallsurfacewater bod-ies,the Nand P loads tosurface watersshould bereduced by approximately50%[39].MeasuresintheﬁfthNitrateAction Pro-gramme,however,willnotreducenutrientloadsfromagricultural soilstosurfacewaters.Duetoimprovementsinwastewater treat-ment,nutrientconditionsareexpectedtoimproveonlyslightly. However,insomeregions,nutrientconditionsmaydeterioratedue totheincreaseofdairycattleandtheassociatedincreaseofNand Pexcretionsince2012inanticipationontheendofmilkquotain 2015.Thisincreasewillalsoincreaseapplicationofdairymanure andNleaching.

Model calculations furtherindicate that the average nitrate concentrationintheuppergroundwaterofthesandregionwill decreasefrom57to52mg/lin2027andinthesouthernregion from78to68mg/l[53].In2030ammoniaemissionsareexpectedto decreasebyabout10%relativeto2013.Combinedwiththeeffectof reductionofNOxemissionthiswilldecreasethenatureareawhere

criticalNloadsareexceededby7%[54].

Sowithpoliciescurrentlyinplace,theexpectedreductionof pollutionbynutrientswillbesmallcomparedtowhathasbeen achievedduringthepastfewdecades.ThecostsforWFDmeasures are,however,substantial.VanGaalenetal.[7]estimatedthetotal costsofproposedmeasuresfortheWFDtobearound4.1billion eurosfortheperiod2009–2027.Additionalcostsforfarmersare, however,smallbecausetheDutchRBMPshardlycontainany mea-surestoreducenutrientloadsfromagriculture(Section3.6.2).The additionalcostsfortheWFDarethereforeprimarilycoveredby regionalWaterBoardsandhouseholds,whichmayconﬂictwith thepolluterpaysprinciple[7].

5. Optionsforpoliciestoimprovetargetachievement

Ouranalysisshowsthatconsiderableadditionaleffortisneeded toachieveallenvironmentaltargetsandobjectivesofthethree directives.In this section we describe optionsfor future target achievementandtheircost-effectiveness(i.e.Dperkilogram emis-sionreduction).

ImplementationoftheNitratesDirectivewithrestrictionson theapplicationofNandPwillsigniﬁcantlyreduceemissionsto sur-facewatersin2027(Table4).However,thelastNitratesActionPlan (2014–2017)didnotfurthercontributetoreduction ofnutrient emissionstosurfacewatersbecausethisActionPlanwasprimarily

developedtomeetthenitratetargetof50 mg/lingroundwater [[7]; seealso Section4.4]. Restrictionsonapplication are cost-effectivetoreducetheNloadtosurfacewaters,butnotforPin viewoftheslowresponseofPleaching.Tofurtherincreasethe cost-effectivenessofnutrientpolicieswhileminimizingnegative economicimpactsofthesepolicies,applicationstandardscouldbe differentiatedregionally.Criteriafordifferentiationcouldbethe sensitivityofagriculturalsystemstonutrientlossesandproximity ofsensitivehighvalueecosystems.Differentiationofapplication standards may increase the risk of manure fraud. Measures to reducemanurefraudandexceedanceofNandPapplication stan-dardsarethereforenecessary.

To further improve the ecological status of surface waters, a number of additional measures to improve the hydro-morphologicalstatuscouldbetaken.However,VanGaalenetal. [7]concludedthatinmanysurfacewaterbodiesthenutrient sta-tuswillremainthelimitingfactor toachievebiological targets. Measurestoimprovewatertreatmentwouldbeattractivebecause thesearegenerallymorecost-effectivethanmeasurestoreduce nutrient inputs from agricultural ﬁelds(Table 4)[39]. Further-more,measurestoreducepointsourcesshowafastresponsewhile responsetomeasurestoreduceagriculturalinputsaregenerally subjecttodelaysofuptodecades.However,measuresin agricul-tureareoftentheonlyoptiontoreducenutrientloadsupstreamor inuplandlakeswherepointsourcesareabsent.

Inadditiontonationalpolicies,regionallydifferentiated miti-gationmeasurestoreducenutrientlossesfromagriculturalsoils couldbeimplemented.Suchoptionscouldincludeinstalmentof bufferzones,miningofphosphorus,(controlled)drainage, preci-sionagricultureandmeasurestoreduceincidentallossesbyrunoff and preferential flow (see Ref. [36] for anoverview of mitiga-tionoptions). Regionalmitigationoptionshave a highemission reductionpotentialandareforphosphorusgenerallymore cost-effectivethangenericrestrictionsonPapplication(Table4).Thisis confirmedinpilotsinitiatedbytheagriculturalsectorinclose co-operationwithregionalauthorities(http://agrarischwaterbeheer. nl/).The challenge is, however, to move from pilot studies to largescaleimplementation.Asmentionedabove,financialsupport could facilitate implementation. Financial incentives are, how-ever,nottheonlykeytosuccess.Awarenessraising,practicability and riskperception areequallyimportant [57].A shifttowards goal-oriented policies that allow farmers greater flexibility in implementingmeasurescouldstimulateinnovationandimprove targetachievement[58,59].

Themostrobustandeffectiveoption forimprovingthe eco-logicalstatusofsurfacewatersinthelongrunisminingofsoil phosphorusbyzeroP-applicationinagriculturalsoilsthataffect sensitivesurfacewaters[60].Thesesoilscompriseabout5–10%of thetotalagriculturalarea[53].Thecostsofminingofsoil phos-phorus are, however, substantial (Table 4).Costs consist of (i)

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highercostsformanuredisposalbecausetheareawheremanure can beapplied will be reduced by 5–10%, (ii)lower economic yieldsperhectareduetotheneedtouselowervaluecropsfor miningof soil phosphorus,and (iii) risk of cropyield loss due to soil P-deﬁciency. These costs are highest for those farmers thathavemanyﬁeldswithahighsoilPstatusborderingsurface waters.

Thecostsoftheabovemeasuresaresubstantialandmayaffect competivenessoftheagriculturalsector.Onthelongrunpolicies mayneedtobedevelopedtotransferbackpartofthesocietal bene-fitsofreducedNandPemissionstofarmers.Incurrentcommodity andfoodmarketsit is,however,difficulttotransferthecostof cleaneragriculturalproductiontoconsumers.Thequalityofthe finalproductsisnotimprovedbybetternutrientmanagementand consumersaregenerallyunwillingtopayabonus,likethey increas-inglydoforfoodthatwasproducedinananimalfriendlywayorfor organicproducts.Anoptioncouldbetocompensatefarmers; how-ever,financialcompensationschemes,e.g.throughtheCommon AgriculturalPolicyorbynationalregulationrequirelong negotia-tionsandmayconflictwithEUregulationsaboutfaircompetition andopenaccesstomarkets.

Wheretargetscannotbeachievedwithadditionalmitigation optionsorwherefinancialcompensationschemesarenotpossible, politicalchoiceshavetobemadebetweenecologyandfarmingfor theworldmarket.Thiswouldimplythatinregionswhere ecosys-temvaluesarehigh(e.g.Natura2000areas)nutrientinputlevels arelimited byecosystem demands andwill notallow fertilisa-tionratesinaccordancetoagronomicdemand.Intheremaining andlargerpartofregionsnutrientinputsaresetinaccordanceto agronomicdemandandgoodagriculturalpractice.Regionswhere nutrientinputsarelimitedwilldevelopmoreextensiveformsof mixedfarming.Continuationoftheseformsofagricultureismore beneficialforsocietythanstoppingagriculturealtogetherasit pro-videsotherservicesthanfood,suchasregulationofwaterquantity, carbonsequestration and culturalservices [61].A key factorto implementsuchapolicywouldbetoredistributecostsand ben-efitsbetweenspecific groupsof farmers orregions. Thiswould implybetterintegrationoftheCommonAgriculturalPolicywith environmentaldirectives.

6. Conclusions

Implementationof theND hasled to a more balanced fer-tilisationand decreaseofN andPsurpluses. Inresponsetothe decreaseofNsurpluses,alsothenitrateconcentrationinshallow groundwaterdecreased. However,thenitratetarget of 50 mg/l isstill exceededathalfofthemonitoringlocationsinthesand region.DecreasingtrendswerealsofoundforNandPinputsto surface watersbut the number of water bodies where allfour biologicalindicatorsscored“good”wasonly5%.Individual indi-catorsimprovedslightlybutthiswasmostlyduetomeasuresfor theWaterFrameworkDirective(betterperformanceof wastewa-tertreatmentplantsandadjustedhydro-morphology)andnotto reducednutrientlossesfromagriculture.TheNEC-NH3Directive

wasveryeffectivetoreduceemissionsofammoniabutcriticalloads ofnitrogenwerestillexceededinthemajorityofecosystems. How-ever,healthbeneﬁtsofmeasuresreducingtheconcentrationsof ammoniaaerosolsweresubstantial.

Thereisastrongoverlapinecologicalgoalsofthethree direc-tives;however,reductionofdifferentsourcesofnutrientsislaid downinsingleregulatedpolicies.Thispiecemealapproachcauses risksofinefﬁciencyandstagnationofprogress.Forexample65% ofthecurrentnutrientloadtosurfacewatersiscausedby agri-culturebuttheDutchimplementationoftheWFDhardlycontains measurestoreducenutrientsinputsfromagriculture.Therefore

coordinationofmeasurestoimplementtheND,WFDand NECD-NH3isimportant.

NutrientpolicieshavegeneratednetbenefitsforDutchsociety. Themeanannualcostfornutrientrelatedmeasureswas approxi-mately500millioneuros.Costsweremainlyforthelivestocksector andconsistedofadministrativecosts,costformanuredisposaland costsfordepreciation ofequipment.Annualsocietalbenefitsof ammoniaandnitratepolicieswereestimatedusingawillingness topayapproachandrangedbetween900and3700millioneuro. Theapparentnetbenefitof400–3200millioneurossuggeststhat stricternutrientpoliciesmayhavebeenjustified.

Withpoliciescurrentlyinplace,theexpectedreductionof pol-lutionbynutrientswillbeinsufﬁcienttoreachthegeneralgoalsof thethreedirectives.Theeffectivenessofpoliciescouldbeincreased bybetterenforcementofmanureapplicationstandards.Toreach moretargetsinacost-effectiveway,nationalpolicies(suchas dif-ferentiatedmanureapplicationstandardsandcompulsorymanure processing)should besupplemented by regional measureslike bufferzonesalongwaterbodies,adjusteddrainage,precision agri-cultureand measurestoreduceincidental lossesbyrunoff and preferentialﬂow.Themostrobustoptionforthelongrunwould beminingofsoilphosphorusbyzeroP-applicationinagricultural soilsthataffectsensitivesurfacewaters.

Wheretargetachievementcannotbecombinedwith competi-tiveagriculture,politicalchoiceshavetobemadebetweenecology andagriculture.Thiswouldimplythatinregionswhere ecosys-temvaluesarehigh(e.g.Natura2000areas)nutrientinputlevels arelimitedbyecosystemdemandsandwillnotallowfertilisation ratesinaccordancetoagronomicdemand.Akeyfactorto imple-ment sucha policywould betoredistributecosts andbeneﬁts betweenspeciﬁcgroupsoffarmersorregions.Thiswouldimply betterintegrationoftheCommonAgriculturalPolicywith envi-ronmentaldirectives.

Acknowledgements

We thank theDepartment for Environmental Quality ofthe NationalInstituteforPublicHealthandtheEnvironment(RIVM) fortheuseofresultsoftheMineralsPolicyMonitoringProgramme (LMM) and Arno Hooijboer for his comments. We also thank WageningenUniversityandResearchCentre;MargaHoogeveen, Harrie Luesink and Ton van Leeuwen from the Agricultural EconomicsResearchInstitutefortheuseofdataoftheFarm accoun-tancyDataNetworkandfortheirusefulcomments,andLeoRenaud fromAlterraforprovidingNleachingandrunoffdata.Finally,we thankJohanBouma,emeritusprofessorofsoilscience, Wagenin-genUniversityandourcolleagueSonjaKruitwagenandfortheir suggestionstoimprovethemanuscript.

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