16
1 Demonstration Test Catchments Newsletter - Winter 2015/16 Welcome to the Winter 2015/16 edition of the DTC Newsletter highlighting some aspects of the research, recent key activities, events and information on related projects with links for you to follow up on more detailed information about individual items and topics of interest. If we knew what we were doing it would not be called research, would it? Albert Einstein Storm Desmond Causes Devastating Floods in River Eden Catchment Storm Desmond brought record-breaking rainfall and associated run-off to the north-west of England in general and the Eden catchment in particular, during the weekend of 5/6 December. The slow moving frontal rain fell onto saturated ground with a gauge at Honister Pass recording 341.4mm of rainfall in 24 hrs on 5 December, setting a new UK record (beating the previous one of 316.4mm set in November 2009 at Seathwaite, in Cumbria). A new 48-hour record was also set, when 405mm was recorded at Thirlmere also in Cumbria and there has been record rainfall recorded in December for a number of places in Cumbria and Lancashire (as well as in Yorkshire and N Wales). (http://blog.metoffice.gov.uk/2015/12/) An estimated 5200 homes were flooded with Carlisle at the bottom of the Eden being particularly badly affected. Bridges and roads have been washed away, railways blocked, farmers lost livestock and, tragically, two people died in floodwaters. The rain and floodwater has potentially moved a large amount of nutrient from agricultural land into the river system. At time of writing the EdenDTC team were still assessing the health of their monitoring kit and studying data but the impact of Desmond should give further insights into the role of extreme weather events (severe storms) in mobilising nutrient flux from land to river, but it is clear that a large load of nutrients and topsoil were moved into the catchment. Simon Johnson (Director of the Eden Rivers Trust (ERT)) said… “there could be a real opportunity… to re-engage the public to drive a better understanding of catchments, bust a few myths and develop resilient community groups that can also still enjoy and value rivers.” Storm Desmond over Cumbria Unequal rainfall distribution in the first 3 weeks of December Eden

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DemonstrationTestCatchments

Newsletter-Winter2015/16

WelcometotheWinter2015/16editionoftheDTCNewsletterhighlightingsomeaspectsofthe

research,recentkeyactivities,eventsandinformationonrelatedprojectswithlinksforyouto

followuponmoredetailedinformationaboutindividualitemsandtopicsofinterest.

If we knew what we were doing it would not be called research, would it?

– Albert Einstein

StormDesmondCausesDevastatingFloodsinRiverEdenCatchment

• StormDesmondbroughtrecord-breakingrainfallandassociatedrun-offtothenorth-westofEnglandingeneralandtheEdencatchmentinparticular,duringtheweekendof5/6December.TheslowmovingfrontalrainfellontosaturatedgroundwithagaugeatHonisterPassrecording341.4mmofrainfallin24hrson5December,settinganewUKrecord(beatingthepreviousoneof316.4mmsetinNovember2009atSeathwaite,inCumbria).Anew48-hourrecordwasalsoset,when405mmwasrecordedatThirlmerealsoinCumbriaandtherehasbeenrecordrainfall

recordedinDecemberforanumberofplacesinCumbriaandLancashire(aswellasinYorkshireandNWales).(http://blog.metoffice.gov.uk/2015/12/)

Anestimated5200homeswerefloodedwithCarlisleatthebottomoftheEdenbeingparticularlybadlyaffected.Bridgesandroadshavebeenwashedaway,railwaysblocked,farmerslostlivestockand,tragically,twopeoplediedinfloodwaters.Therainandfloodwaterhaspotentiallymovedalargeamountofnutrientfromagriculturallandintotheriversystem.AttimeofwritingtheEdenDTCteamwerestillassessingthehealthoftheirmonitoringkitandstudyingdatabuttheimpactofDesmondshouldgivefurtherinsightsintotheroleofextremeweatherevents(severestorms)inmobilisingnutrientfluxfromlandtoriver,butitisclearthatalargeloadofnutrientsandtopsoilweremovedintothecatchment.SimonJohnson(DirectoroftheEdenRiversTrust(ERT))said…“therecouldbearealopportunity…tore-engagethepublictodriveabetterunderstandingofcatchments,bustafewmythsanddevelopresilientcommunitygroupsthatcanalsostillenjoyandvaluerivers.”

StormDesmondoverCumbria

Unequalrainfalldistributioninthefirst3weeksofDecember

Eden

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AddressingaquestionfromtheEnvironmentAgencyastowhethersoilmanagementhadaroletoplayintheseverityoftheflooding,ProfessorPhilHaygarthsummarisedhisthoughtsin4categories:

1. Thereisevidenceattheplotandfieldscalethatsoilmanagement,whichpromotesstructureandwaterretention,canslowwaterrun-off.

2. Theextenttowhichthisknowledgecanbeconfidentlytranslatedtothemitigationoffloodingeventsatthecatchmentscaleismuchlessclear,catchmentsarecomplex.

3. Soilstructuralmanagementintheuplandscancontributetoreducedrun-offbutmustbepartofabiggerandintegratedsolution.

4. ItappearsthattheeventsinCumbriaduringStormDesmondweresoseverethatsoilissuesprobablywouldhavebeenofmarginalimportanceinthiscase.

Isthereevidenceof‘biogeochemicalstationarity’intheRiverWensum

catchment?TheWensumDTCteamhasbeenexaminingtherelationshipsbetweenrainfall-runoff,catchmentconnectivity,antecedentmoistureconditionsandfertiliserapplicationwithnitrate-Nandtotalphosphorus(TP)fluxesintheBlackwaterstudyareaoverthreehydrologicalyears(2012–2014).Usinghigh-resolutiondata(30min)generatedfrombanksidemonitoringkiosks,investigationshaveuncoveredarangeofimportantmeteorologicalandhydrogeochemicalphenomenawhichhaveenhancedourunderstandingofthisintensivearablesystem.Theseareasfollows:

• annualprecipitationtotalsdidnotvarysubstantiallybetweenyears,yetthetimingofrainfalldidstronglyinfluencerunoffgenerationandsubsequentnitrate-NandTPfluxes;

Figure1:CroptypesandfertiliserapplicationintheBlackwatercatchmentduringthethreeyearmonitoringperiod.(a–c)croptypes;(d-f)inorganicandorganicnitrogenfertiliserapplicationrate;(g-i)inorganicandorganicphosphorusfertiliserapplicationrate.Seepaperforfurtherdetails.

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• thegreatestnitrate-NandTPfluxesoccurredonlywhentheshallowgroundwaterlevelwaswithin0.6mofthegroundsurfaceandrunoffcoefficientsweregreaterthan0.1;

• thewetwinter2013resultedinelevatedshallowgroundwaterlevelswhichledtomorefrequentactivationofsub-surfacepathwaysandtiledrainflows;

• acrossthethreeyears,dryantecedentconditionshadatemporaryeffectinelevatingTPloads;

• evidenceofTPsourceexhaustionafterconsecutivestormeventswasdetectedandcanbeattributedtotherepeateddepletionoftemporarilyconnectedcriticalsourceareastotherivernetworkviaimpermeableroadsurfaces;

• finally,andmostimportantly,fertiliserapplicationvariedconsiderably(upto41%)acrossthethreeyearsduetodifferencesincroprotationbetweenfarms.However,proportionalreductionsinannualriverinenitrate-NandTPloadingswerenotobservedatthesub-catchmentoutlet.Nitrateloadingswereslightlyhigherduringfertiliserapplication,buttherewaslittlerelationshipbetweenPfertiliserapplicationandriverineTPload.Theseresultsindicatethatthisintensivearablecatchmentmaybeinastateof‘biogeochemicalstationarity’,wherebylegacystoresofnutrientsarebufferingthestreamagainstannualchangesinfertilisernutrientinputs.

FurtherdetailsonthisresearchcanbefoundinarecentlypublishedarticleinScienceoftheTotalEnvironment:OutramFN,CooperRJ,SünnenbergG,HiscockKM,LovettAA.2015.Antecedentconditions,hydrologicalconnectivityandanthropogenicinputs:Factorsaffectingnitrateandphosphorustransferstoagriculturalheadwaterstreams.ScienceoftheTotalEnvironment.DOI:10.1016/j.scitotenv.2015.12.025.Contact:RichardCooper([email protected])

DTCDataandtheDataArchive

TheDemonstrationTestCatchmentArchiveProjectfinishedattheendofJanuary2015.TheoutcomeoftheprojectwastheAgriculturalandEnvironmentalDataArchive(AEDA),whichhasbeenonlinefornearlyayearandcanbeaccessedatwww.environmentdata.org.Varioususershavebeenaddingdatasincethattime,notonlyfromtheDTCconsortiaandtheDefraAgriculturalGreenhouseGasPlatform,butalsofromtheFreshwaterBiologicalAssociationwhobuiltandhousethearchive,andothercontributorssuchasSyngenta,theEnvironmentAgencyandTheAtlanticSalmonTrust.TherearealsosomenewcontributorsfromtheDefraSustainableIntensificationPlatformandsomehistoricalGreenhouseGasdata.Addingdatatothearchiveisonlythefirststepinmakingitavailabletothepublic.Oncethedatahasbeenaddedintheproperformatitcanbepublished.Publicationinvolvessubmittingthedataforaseriesofautomatedchecksbythearchivesoftwareandalsohumanreviewbythearchivestaff.Ifalliswellitwillbepublishedandmadeavailabletothepublic,aDigitalObjectIdentifier(DOI)iscreatedforthedatasetanditbecomesascholarlyworkwhichcanbecitedinscientificpublications.YoucanseeexamplesofsomepublishedDTCdataat:http://www.environmentdata.org/clist/dtcwensum.Intheelevenmonthssincethearchivewasmadeavailableseveralimprovementshavebeenmadethatshouldmakeiteasierforpeopletoadddatatothearchive.TheDOIcreationfunctionalityhasbeenaddedandthequalityofthepublisheddatainthearchivehasbeenenhancedbymakingitpossibletoachievecertificationfromtheOpenDataInstitute(ODI).More

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andmoredatawillbeaddedtothearchiveastimegoesonandthetechnicalcapabilitiesofthesystemwillbeimprovedonacontinuousbasis.Contact:MikeHaft([email protected]).

TheUseofRemoteSensingTechniquesinUnderstandingDiffusePollution

TheDTCteams,intheEdencatchmentparticularly,havebeentriallingavarietyofremotesensingtechniquestoseeiftheycanaddvalueinunderstandingthecatchmentsystem.Inthefollowingfewarticlessomeofthisworkissummarised.

RealTimeCameraWorkAsetofcustom-maderealtimewebcameraswereinstalledateachoftheEdenDTCcatchmentoutletsaspartofthefirstphaseoftheDTCproject.ThesecamerascapturedVideoGraphicsArray(VGA)low-resolutionimages(640x680pixels)at10minuteintervals,whichweretransmittedtotheweb-serverviathemobilephonedatanetwork.TheimagesweredisplayedontheEdenDTCwebsiteandarchivedforfutureanalysis.Theobjectivesforthisinstallationwere:

• Toallowthefieldteamtoseethecurrentconditionsatthesitestoassistwithmaintenance;and

• Toallowstakeholderstoseethesitesandcomparethemonitoringresultstotheoutvisualrecord.

Theliveimagesfromtheweb-camswerepopularonthewebsite.Forexample,thecameraattheMorlandoutletwasviewed245timesin2013,whilethewaterchemistrydatawasviewed320times,indicatingthattheusersofthewebsitewerefindingvalueintheseimages.Thecamerasalsocapturedsomeexemplarstormeventsandstreamresponses(Fig2).

Therewereproblemswiththereliabilityofthecameras,requiringfrequentattentiontokeepthemrunning.Therewerealsoissueswithalackof3GmobiledatasignalattheThackthwaiteBecksite.Ultimately,theperformanceofthecameraswasnotsufficienttojustifythecontinuedtimecostofmaintainingthesystem;(thecamerasupplierhassincebeenboughtoutbyMeteorCommunications,whohaveupdatedandrefinedthecamerasintoanewproduct).

Figure2:StormflowresponsecapturedatThackthwaiteBeckwiththerealtimewebcameras

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Conclusions• Thereal-timecamerasprovidedusefulcontextualinformationtoboththefieldteamand

towebsiteusers;• Theeventscapturedbythecamerashavesupportedpresentationsontheproject;• Thequalityandlevelofmaintenancerequiredforthecamerasmeantthattheywereon

trialforpartoftheproject;• Futureprojectscouldconsiderinstallingnewversionsofthistechnologyifthequalitycan

beimprovedandmaintenancerequiredcanbereduced. MonitoringCattlewithCameras–Exploringthetemporaldynamicsbetweencattlein-stream

presenceandsuspendedsolidsinaheadwatercatchmentCattlein-streamactivityispotentiallyanimportantcontributortowaterpollutionfromagriculture.Inordertoaddresstheuncertaintyabouttheextenttowhichcattleimpactonsedimenttransferprocesseswithinthefluvialchannel,acomparisonofhigh-resolutionmonitoringdataofcattleactivitywithinthestreambedagainsthigh-resolutionwaterqualitydatacollectedoveraperiodofseveralmonthswasconducted.BushnellTrophyXLT119455motionsensorcameras,withinfrarednight-visionLEDs,wereusedtocapturein-streamactivityofcattle,withatime-delayof10secondsbetweeneachshutterresponsetriggeredbythemotionsensors.inanunfencedreachoverafour-monthperiod.Resultswerecomparedagainsthigh-resolutionSSCdata.Overthedaysthatcattlegrazedthefield,58%oftheinstanceswhensuspendedsolidsconcentrations(SSC)crossedthe25mgl-1FreshwaterFishDirectiveguidelinethresholdcanbeattributedtocattlepresenceinthestream.Flowwasthemaindriveroftotalsedimentstransportedoverthestudyperiod,andnorelationshipwasfoundbetweenSSCandtheabsolutenumberofcattlefeetinthewater.Hysteresisanalysisindicateda‘first-flush’oflocalsedimentsrapidlymobilisedduringthenon-cattlerelatedSSCevents,aresultofcattleproximitytochannelmargins.Resultsdemonstrateatemporallagbetweencattlein-streampresenceandacriticalamountoftheircontributiontosedimentload,andthatmonitoringonlyinstantaneouslywithcattleactivitymayleadtounderestimationoftheirpollutionimpact.Theworkhighlightsthatcattlehaveanobservableimpactonwaterpollution,althoughatemporallagbetweencattlein-streampresenceandacriticalamountoftheircontributiontosedimentloadwasdemonstrated.Thisstudyhelpsdemonstratethelossofenvironmentalinformationthatcanresultfromlowresolutionmonitoringprogrammes,andisavailableinfullathttp://pubs.rsc.org/en/content/articlepdf/2014/em/c3em00686g?page=search.Monitoringchangesindiffusepollutionsourceriskwithtime-lapsephotographyTherearemanyfactorswithinthelandscapethatcanaffectdiffusepollutionsourcerisks,whichvaryovertheyear.Examplesincludesnowcoverdynamicsdrivingoverlandflownotdirectlyconnectedtoprecipitationonthatday,andchangesinsolarreceiptresultingfromcloudcoverandlandcoverchangesensuingfromagriculturalpractices.AnapproachthatwastrialledwithinthefirstphaseofDTCwastheuseofatime-lapsecameratocreateavisualrecordonthelandscape,whichcouldthenbeprocessedtogiveacontinuousrecordofsuchfactors.Itishopedthatthisextrainformationmayprovideusefulcontextandbackgroundinformationfortheinterpretationofthein-streammonitoringdata.

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AsinglecamerawasinstalledintheDacresub-catchmentoftheEdenDTC.Thelocationwasselectedduetothesuitabilityofthetopographyfortheapproach,andlocalissueswithsnowmeltthataremostrelevantatthissite.ThecameralocationandatypicalimageareshowninFig3.ThecamerainstalledwasaCanon5DmkIDSLRwitha24mmf2.8lenssettof5.0,withafixedISOof200inapertureprioritymode.Thissetupgaveahorizontalangleofviewof73.7°.Thecamerawastriggeredtotakeanimageevery10minutesandhasbeeninstalledsinceJan2014.ConvertingImagestoInformationImageswereprocessedwiththePythonImageLibraryandSciPytoextractinformationonthechangingcharacteristicsofthelandscape.Theapproachtakenforcloudcoverandsnowcoverfollowedthesamesteps:

1. Definetheareaofinterestwithintheimageforanalysis.Fortheclearskies,thisisanareaextractedfromthesky,whileforthesnowcoverthisareawasdefinedasthelocalforegroundfield.

2. AGaussianblurfilterwasappliedtotheimagewithahighradius(200)togiveaconsistentcolourvaluewithintheextractedareaofinterestimage.

3. Thered,greenandbluecomponentsofthecolourwereextractedforanalysis.a. For‘clearskies’,theindexwasdefinedasblue/((green+red)/2)andhencethe

lowervaluesrepresentcloudydaysandhighervaluesrepresentblueskydaysb. Forthe‘snowiness’,theindexwasdefinedasblue/greenwithvaluestowards

onerepresentingsnowcoverThechangesintheoverallscenewereassessedbycomparingthestatisticaldifferencesbetweenpairsofimages.Twoapproachesweretested,thefirstcomparedthecurrentdaytothepreviousdayandthesecondapproachcomparedeachdaytotheaveragedscenefromthewholeyear.Thedifferencesbetweentheimagesweredefinedasthe‘Manhattan’difference,wherebythemeanmovementinbrightnesslevelsperpixeliscalculatedaftertheimageshavebeenconvertedtogreyscaleandnormalised.

Figure3:Thelocationofthetime-lapsecameraandatypicalimageacquiredfromthesite(24/06/14).Theredtriangleinthemapshowsthecameradirectionandangleofviewoftheimages

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InitialResultsFig4showstheinitialresultsforthe2014calendaryearfortheclearskiesandsnowinessindices,withexampleimages(Fig5).Theseinitialresultsarebasedonthemiddayimagesfromeachday.

Fromtheresults,itcanbeseenthatthesnowinessindexcorrectlyidentifydayswithsnowcoverwhentheindexvalueexceeds0.87.Thereisastrongseasonaltrendinthesnowinessindex

12/02/14ClearSkies:0.67Snowiness:0.96

12/05/14ClearSkies:0.82Snowiness:0.69

26/08/14ClearSkies:0.82Snowiness:0.53

12/12/14ClearSkies:0.79Snowiness:0.96

valueswiththelowestvaluesinthesummer.The‘blueskies’indexshowsthehighlevelofcloudcoverthroughtheyear,withrelativelyfewdaysbeingcloudfree(8.5%ofdayshaveanindexvaluegreaterthan0.75).TheexampleimageinFig5from12/05/14showsissueswithcondensationwithinthewaterproofhousingofthecamerainstall.Thiscondensationreducestheimagequalityforfinedetail,butitisstillpossibletoextractinformationontheskystatus.Fig6showsthechangesovertimeforthedailydifferenceswhencomparedtothepreviousdayandtothemeanimage.TheresultsinFig6showthatthedifferencebasedindicesarecapableofidentifyingthedaysoftheyearwerethelandscapeorclimatedifferfromthe‘normal’conditions.TheapproachsuccessfullyidentifiedtheincreasedsnowcoverinFebruary2014,theoccurrenceofachangeintheweatherconditionsfromcloudtoclearskiesinApril2014andthereverseinAugust,andfinallytheoccurrenceofsnowfallinDecember2014.

Figure4:Changesintheclearskiesandsnowinessindexoverthe2014calendaryear

Figure5:Changesintheclearskiesandsnowinessindexoverthe2014calendaryear

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11/02/14

14/04/14

09/08/14

11/12/14

12/02/14FromPrevious:35.3FromAverage:59.3

15/04/14FromPrevious:44.6FromAverage:46.2

10/08/14FromPrevious:32.7FromAverage:30.8

12/12/14FromPrevious:52.4FromAverage:14.8

Figure6:Changesovertimefordailydifferenceswhencomparedtothepreviousdayandtothemeanimage

Conclusions• Time-lapsephotographyofacatchmentandlandscapehasthecapabilitytoadd

significantcontextualinformationtocomplementandsupportthein-streamwaterchemistrydatasets;

• Theapproachgeneratessignificantamountsofdata,andhencetoolsareneededtoidentifytheimportanttimesandassociatedimages;

• Thepresentedindicesarecapableofidentifyingpropertiesoftheenvironmentsuchascloudcoverorsnowaccumulation/melt;

• Itispossibletoidentifythetimingoflargechangesinthelandscape,eithercomparedtothepreviousdayortotheannualaverageconditions.

UseofUnmannedAerialVehicles(UAVs)forDiffusePollutionUnderstandingPartoftheoriginalconceptualmodelofthegenerationofdiffusepollutionwithinthelandscapewasthatakeypartoftheprocesswasdrivenbyinteractionoftherainfallintensityandthe

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statusofthelandsurface.Landsurfacecharacteristicschangesignificantlyonintra-andinter-annualtimescalesandhence,tounderstandthecatchmentresponsetoastormevent,knowledgeofthecurrentstatusofthelandscapeisneeded.Tomonitorthesechanges,variousremotesensingapproacheswereassessed.Bothsatellitebasedremotesensingandaerialphotographywerediscountedduetoprohibitivecostsandpotentialissueswithcloudcover.Therefore,aspatiallytargetedplanusingaUAVwasdevelopedasawaytogetsomeinformationonthelandscapestate.

Exampletruecolourimage Landcoverclassifiedimage.Redare

bareareasandbluearevegetatedareas.Imageshows6.4%bare,erodiblesoil.

Changesinthegroundvegetationcover

TheequipmentsourcedwasaMicrodronesMD4-200quadcopterUAV1,whichofferedprogrammableflightroutesusingGPSandagroundstationshowingtelemetryfromthecraft,includingbatteryvoltage,positionandavideofeed.ThisisthesameUAVthatwasusedbytheEnvironmentAgencyandotherUKpublicsectororganisationsatthetime.TheMD4-200iscapableofcarrying200gpayloadofasmallRGBdigitalcamera.

Proofofconceptresults-ThefirstimageinFig7isatruecolourimageofaspringsownbarleyfieldatSewborwensFarmnearPenrith;thesecondisaclassifiedimagewhichshowsvegetationversussoilcover;andthefinalimageshowthechangeinvegetationcoverovertimeforthissite.

Lessonslearnt• Withinphase1ofEdenDTC,therewasinsufficientpersontimetoimplementtheplanned

monitoringschemewithoutimpactingonothermeasurements;• Dedicatedtimeandresourceisrequiredtoacquirehighqualityimagesandtoprocess

themintousefulinformation;• WiththeMD4-200,thereisanarrowwindspeedwindowforeffectiveandsafeoperation.

Thecraftissensitivetowindspeedgusts,whicharenotalwaysrecordedinweatherdata;• Repairtimescanbelongandcancreateissueswithapplication;• People(stakeholdersandpublic)areinterestedinthetechnologyanditprovidesan

effectiveengagementtool.

NextStepsWithinDTCphase1theoperationalisationofthespatialmonitoringwasnotpossiblewiththeUAVduetolackofsufficientpersontimeandtechnologicallimitations.WithinDTCphase2weareplanningtouseUAVequipmentfromDurhamUniversitytomonitorasetofkeyfieldswith1http://www.microdrones.com/en/products/md4-200/at-a-glance/

Figure7:ExampleimageprocessingforaspringsownbarleyfieldwithintheEdenDTCmonitoredarea

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higherosionriskandeffectivepathways(strongconnectivity)totheriverchannels.Thenewequipment(DJIS1000withZenmusegimbal,carryinga24mpAPS-CRGBcamera)iscapableofflyinginfarhigherwindspeedsandcancapturehigherresolutionandhigherprecisionimages.Theseimprovedimageswillenabledetailedterrainmodelsandcovermapsforthehotspotfieldstobecreated.Exampleswillbeshowninfutureprojectupdates.

Farmer-LedMonitoringintheWensumDTC

AspartoftheknowledgeexchangeactivitiesoftheWensumDTC,severalsmalltrialswithhand-heldmonitoringequipmentwereconducted.SeveralHannaHI9829probeswereinitiallypurchased,whichcanmeasurenitrate,turbidity,dissolvedoxygenandwatertemperature,butthesewerenotsufficientlyreliableinvalidationtestsusingsamplesthatwerealsoprocessedbytheanalyticallaboratoryatUEA.SeveralfarmersattendingtheWensumDTC/NFUmeetinginNovember2011offeredtoparticipateinundertakingmonitoringoffielddrainsontheirownfarms.SincetheHannaprobesdidnotproveeffectiveinspring2012wesuppliedthreefarmerswithnitrateteststripssothattheycouldassessvariationsinwaterqualityfromfielddrainsunderdifferentcrops.Thesestripstypicallycostabout£10foratubeof50strips,buthavelimitedsensitivitywithcolourchangesthatcanbematchedtoindicatorlevelsof(forexample)0,5,10,25,50,100,250and500mgl-1NO3.Threefarmersusedthestripstotakemeasurementsonthreeorfourfieldseveryfortnightorsoforthreemonths(MarchtoMay2012).Betweenthem,theycollected65datapointson14datesfrom11locations.Table1showstherangeofreadingsrecordedfromdrainsonfieldswithavarietyofdifferentcrops.

Minimum

(mgl-1NO3)

Maximum

(mgl-1NO3)

Oilseedrape 0 5Winterwheat 2 20Sugarbeet 20 80Fieldbeans 20 50Linseed 5 20Herbs 10 20Pasture 5 5Theresultsweresufficientlyreliabletohighlightdifferencesbetweencrops(e.g.concentrations<10mgl-1NO3fromfieldsofoilseedrapewherethecropwasactivelytakingupnitrogenfertiliser,andvaluesintherange20-80mgl-1NO3wheresugarbeethadbeenplanted).However,itwasnotpossibletoidentifyanyconsistentchangesfollowingrainfalleventsandallthreefarmersnotedthattherewasadegreeofsubjectivityinmatchingthecolourchangestotheshadescaleonthesideofthetubes.Basedonthisexperienceitwasdecidedthatweneededequipmentwithgreatersensitivityandthatcouldprovideareadableconcentration(ratherthanrequiringcomparisonwithcolourshades).Ittooksometimetoidentifyapossiblesolution,butinlate2012theDTCpurchasedfiveLovibondMD600Photometers(costing£815each,includingVAT)fromTintometerLtd(http://www.lovibond.com/)andhavebeenpleasedwiththeirsubsequentperformance.

Table1:NitrateteststripmeasurementsfromthreefarmsintheWensum(Apr–May2012)

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Thephotometerscanbesetuptoanalysequiteawiderangeofwaterqualityparameters,althoughsofaronlyphosphate(PO4)andnitrate(mgl-1N)concentrationshavebeenanalysed.Thephosphatetestinvolvescrushingtwotabletsinawatersampleandleavingthemtodissolvefor10minutesbeforetakingareading.Asetof250phosphatetabletscostsabout£50.Thenitratetestismoreexpensive(£150for25tests)andinvolvestubesofreagentswithahighconcentrationofsulphuricacid.Completedriskassessmentformsarerequiredforbothanalysesandithasbeenusefultopurchaseadditionalplasticsboxes,trays,testtubestandsetc.tostoreandmanagetheequipmentandreagents(seeFig8).Todatetherehavenotbeenanyproblemswithsafetyissues.

Thenitratetesthasanadvertisedrangeof1-30mgl-1N.Repeatedanalysesofthesamewatersamplefromafielddrainhavetypicallygeneratedvariationsof1-2mgl-1Naroundthemeanvalue.Forphosphatethereisanadvertisedrangeof0.05-4mgl-1PO4andexperienceshowsthatitisquitepossibletogetresultsvaryingby0.10or0.15mgl-1fromrepeatanalysesonthesamewatersample.Theissuewiththephosphatetestsistoensurethatthetabletsarecompletelycrushedanddissolvedbeforeputtingthesampleinthe

photometer.Beyondthesecaveatsregardingprecision,theequipmentprovedtobereliableandstraightforwardtoexplaintopotentialusers.Overwinter2013-14severalofthephotometerswereloanedtotheCatchmentSensitiveFarmingteamintheWisseycatchmentwhoarecollaboratingwithfarmersrecruitedthroughFrontierAgriculturetotesttheiruse.AnothersetofequipmentwasusedbyaprojectofficerfromtheNorfolkRiversTrust.Experiencesreportedbacktodatearethattheequipmentiscertainlycapableofidentifyingdifferencesinfielddrainnutrientlevelsbetweencrops(e.g.oilseedrapeandwheat)andreductionsinconcentrationsbetweenlateNovemberandFebruary.Onapracticalleveltherehavebeencommentsthatthephotometersarecertainlyanimprovementonteststripsorequipmentfromothersuppliers,butissueshavebeenencounteredingettingallthephosphatetabletstodissolveandtheviewhasbeenexpressedthatmanyfarmerswouldrequireatrainingsessionandon-farmsupporttogetconsistentlyreliableresults.WorkingwithlocalCatchmentSensitiveFarmingofficers,theWensumDTChopestodevelopsuchtrainingandgatherfurtherinsightsonexperienceduringthenexttwoyears.

DefraWorkshop30thNovember:“Experiencesofengagingwithfarmers”

SimonWest(HeadofWaterQualityandAgricultureatDefra)organisedaworkshopinLondoninNovember,invitingseveralDTCresearcherstopresenttheirfindingsandexperienceonchangingfarmers’behaviour.TheworkshopwasattendedbystafffromdifferentpolicyareaswhodealwithagriculturalissuessuchasGMpolicy,animalidentificationandmovements,agriculturaleconomics,animalhealthandwelfare,soils,biosecurity,foodandfarmingevidence,agri-environmentalschemesandhealthandsafety.

Figure8:

LovibondMD600Photometer

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AtthebeginningoftheworkshopProf.AndrewLovettfromtheUniversityofEastAngliaintroducedthedesignandconceptoftheDTCplatform.WillCleasbyfromtheEdenDTCthendescribednumerousexamplesofstakeholderengagementachievedthroughhisworkwiththeEdenRiversTrust.PhDresearcherEmilieVrainledthemainsession,presentingherPhDresultsonfactorsinfluencingfarmeruptakeofwaterpollutionmitigationmeasuresandtheroleoffarmadvice.Theresearchfromherthesiswaspresentedto:1)provideanexemplarofexperienceandbenefitsofengagingfarmersandfarmadvisorsaboutwaterpollution,and2)highlightqualitativemethodswhichcouldbetranslatedtoaidunderstandingofhowbesttoinfluencefarmerbehaviourinothertopicareas,especiallythosewhicharehighlycontested.AlexInman,acatchmentadvisorworkingontheHampshireDTCprovidedsomereflectionsattheendofthefirstsessiontoleavetheaudiencewithfoodforthought.Informativetwo-waydialoguewasachievedthroughoutthepresentationswithallworkshopattendees.TwobreakoutgroupsconsideredhowtheDTCs’experiencemightbetransferrabletotheirpolicyanddeliveryareas.Theywerealsoaskedtocontemplatehowtheirexperiencemightbebuiltintothewaterqualityandagriculturalpolicyanddeliveryarea.Nextstepswerethendiscussedastohowdifferentpolicyareascouldworkmorecloselytogether.Oneattendeestated‘it[theworkshop]wasveryusefulforbringingtogetherpolicyareasandthereforemessages,identifying

whowecanlinkeffortswith.’Itwasagreedmoreeventsshouldbeheldinthefuturetoallowcommonsharingofknowledgebetweendepartmentswithafocusoninfluencingfarmerbehaviour.

NewUpstreamThinkingprogrammetoprotectrivers

ApartnershipofSouthWestWater(SWW),theDevonWildlifeTrust,theCornwallWildlifeTrust,theWestcountryRiversTrustandtheExmoorNationalParkAuthorityisbuildingonworkbegunin2008tochangelandmanagementpracticestoprotectriverswithanewfive-yearprogramme.SupportedbytheNationalFarmersUnion,theEnvironmentAgency,NaturalEnglandandtheFarmingandWildlifeAdvisoryGroup,theprogrammeispartofSWW'slong-termbusinessplantoreduceitsenvironmentalfootprintandmanagetheimpactof

diffusepollutiononcustomers'bills.Theprogrammehastwomainelements:adviceandgrantsforfarmersandtherestorationofpeatlandinpartnershipwithlandowners.

Thelatest£11.8millionprogrammefocuseson11catchmentsacrossDevonandCornwallin2015-20.Thetargetfortheprogrammeis750farmsand1,300haofmoorlandandothersemi-naturallandunderrevisedmanagement.UpstreamThinkingadviserswillbeworkingontheExe,theDart,theOtterandtheYeoinDevonplusgroundwatersourcesinEastDevonandthecatchmentaroundFernworthyReservoir,whileinCornwalltheywillbefocusingontheCober,theTamar,theFalmouthreservoirsandDriftreservoir.

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Grantsaretargetedatfarmswithlandconnectedtoriversabovewaterabstractionpoints.Theaimistoreducetheamountofunwantedsubstancesinriverwater,whichinturnhelpstocontrolthecostofchemicalsandenergyneededtoturnrawwaterintohighqualitytapwater.

Grantscanhelptofundimprovementstoslurrystorage,fencingtokeeplivestockoutofrivers,providingalternativewatersourcesforlivestock,betterpesticidemanagementincludinginvestmentinnewequipment,suchasweedwiperswhichdelivertargeteddosesofherbicide.Farmersmatchthefundingandofteninvestmorebesides,aswellasbeingabletoaccessfurthersourcesoffunding.Farmerswhotookpartintheprogrammein2010-2015savedanaverageof£20,000onthingslikereducedfertilisercosts.Since2008,UpstreamThinkingadvisorshavemade1,700visitstofarmsandallocated180capitalgrantstotalling£2.2million.

ThemoorsoftheSouthWestprovideover40percentoftheregion’sdrinkingwater,andpeatlandrestorationisacrucialelementoftheUpstreamThinkingprogramme.TheExmoorMiresPartnershiphasinvestigatedandrestoredover2,000hectaresofmoorlandonExmoorandDartmoor,andplanstorestoreafurther1,000hectaresby2020.ScientificresearchcarriedoutonthemoorbytheUniversityofExeterhasshownthatrestoredbogsreleaseathirdlesswaterduringstormsand30%lessdissolvedorganiccarbon,whichdiscoloursthewater.ResearchbytheEnvironmentAgencysuggeststheworkishelpingtomaintainriverlevelsduringdriersummermonths.Contact:DrDavidSmithSWWProgrammeManager([email protected])

DTCPhase1Reportavailableshortly-someConclusions

Phase1ofDTChasreachedanumberofconclusionsconcerningthedominantsourcesineachoftheresearchcatchments,thetimingofnutrientexportfromlandtowater,andtherangeofnutrientchemistriesmobilisedandtransportedtostreamsineachofthecatchments.However,universaltruthshavenotemergedfromthisanalysisanditisclearthatcaremustbetakentoensurethatthefindingsfromoneprogrammearenotassumedtoprovideaperfectsolutioninanothercircumstancewithoutpriortestingofthosesolutionsacrossmultiplelandmanagementandgeoclimaticconditions.TheDTCmonitoringhasshownthatstormeventsarehighlyimportantindrivingthefluxofdiffusepollutionincatchmentswherethereisahighproportionofrapidrunoffinpreferentialflowpathways(surfacerunoff,near-surfacequick-flowanddrainflowindrainedlandscapesliketheWensumcatchment).However,itisthemidfloweventsthatdominatenutrientand

sedimentdeliveryincatchmentsdrivenbysubsurfacehydrologicalfunction.Similarly,nitrateisthedominantformofnitrogendeliveredtowaterbodiesinpermeablecatchments,basedontheevidencecollectedhere,butitisaminoritycomponentoftheTNloadinginlivestockfarmingsystemswherethehighstockingdensitiesandabundanceofmanureproductionleadstoenrichmentofwaterswithbothparticulateanddissolvedorganicnutrientfractionswhichwillstimulatebothalgalproductivityandmicrobialmetabolismin-stream.Amonitoringprogramme

thatfocusedsolelyonnitrateinalivestockfarmingcatchmentwouldbeunlikelytobe

sensitivetocurrentmanagementortotargetedon-farmmitigationeffortsinthecatchment.Anotherpointwhichhasemergedisthattherearesignificantuncertaintiesassociatedwithanymonitoringstrategytodetectnutrientandsedimentfluxbehavioursincatchments.Sensorsprovideon-sitehighfrequencyobservations,buttherecanbetechnologicalproblemsto

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overcomewiththeiruse,ifrobustandreliablefindingsaretobegenerated.Simplyrelyingonthesensorswithouttestingtheaccuracyandprecisionoftheobservationswithinanuncertaintyframeworkwillconstraintheusertoimpreciseanduncertainobservations,datastreamswithsignificantgapsandalimitedrangeofdeterminandswhichmightnotbethosebestsuitedtoansweringthequestionposed.Laboratorybasedanalyseshavetheirplace,asqualitycontrolcanensurehigherqualitydata,forawiderrangeofdeterminands,albeitatalowertemporalresolution.Acombinationofmonitoringapproachesislikelytobeneededtogeneraterobust

evidencestreamsforcatchmentmitigationeffortsatanysite.InsynthesisingthesenutrientandsedimentfluxbehavioursfordifferentlandscapetypologiesacrosstheDTCplatform,carefulconsiderationalsoneedstobegiventotheappropriatestatisticaltechniquesthatareapplied(seeLloydetal.2014).Thisensurescorefindingsregardingtheefficacyofmitigationstrategiesallowforthequalityanduncertaintyofdifferentmeasurementstrategies(suchasidentifiedabove);thenaturalvariabilityintimeandspaceofcatchmentsystemsandrelatedclimaticfactors;thedurationoftheevidencebasepreandpostmitigationinlightofinherentnaturalvariabilities;andthedifferentQAproceduresandmonitoringstrategiesbetweenDTCcomponents.Finally,thecontrastbetweentheresponsesofdifferentcatchmentswithvaryingsoilsandgeologytodifferingdegreesofrainfallhasbeenshowntobecriticalindeterminingpollutantloads,andproperlyevidencingtheselectionofmitigationmeasuresinanycatchment,asistheproportionofgroundwaterthatcontributestoriverflow.Consequentlytheimportanceofidentifyingandmanagingrun-offpathwaysduringstormeventsandsubsurfacepathwaysyearroundisakeyfindingofDTC.Themannerinwhichthesebehavioursimpactontheecosystemfunctionandhealthofthereceivingwaterbodiesarediscussedfurtherinthefullreport.

SoilmoisturemonitoringintheWensumDTC

TensetsofsoilmoistureprobeswerefirstinstalledinJanuary2013intheBlackwatersubcatchmentoftheR.Wensumforthepurposeofdeterminingsoilconditions,forexampleinfiltrationbehaviourandfieldcapacityconditions,intheninemitigationmeasuresfieldsatSalle.TheAdconGPRStelemetrysystemenablessoilmoistureatintervalsof10cmtoadepthof90cmtoberecordedat15-minuteintervalsusingAdconSM1capacitance-basedmeasurementprobes.Temperatureisalsomeasuredatthreedepths(15,45and75cm).Profilesofsoilmoisturedevelopmentovertimecanbeusedtocalculatewaterdrainageandevapotranspirationratesandalsodownwardfluxesofdissolvedsolutessuchasnitratewhereporouspotdataexist.AnexampleofthetypeofsoilmoisturedatacollectedisshowninFig9forprobe50413installedinDunkirkfieldatManorFarm,Salle,inmini-catchmentA.ThedataarefortheperiodFebruarytoearlyJuly2013.Thegreenlinerepresentssoilmoistureat30cmdepthandshowsanumberofpeaksinresponsetorainfallevents.ThepeaksinFebruaryandMarchreachmaximum,orfieldcapacity,valuesfortheclayloamsoilatthislocationofabout56%moisturecontent.Followingthewinter,thereisagradualdryingtrendat30cmdepththatbecomesmorepronouncedfrommid-April,andespeciallyfollowingthelateMaypeakinsoilmoisturecontent.Thesoilmoisturecontentatgreaterdepthremainssaturatedforlongerwiththerecordat60cmdepth(darkblueline)onlyrespondingtodryingatthestartofJune.Therecordat90cmdepthshowsnoresponsetodryingbythestartofJuly(lightblueline).Thedatarecordedon3Julygivesoilmoisturecontentsof31.9%,54.4%and59.0%atdepthsof30cm,60cmand90cm,

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respectively.Theredlineshowsthetemperaturerecordedat75cmdepthanddisplaysagradualwarmingfromabout4oCinFebruarytoavalueof13.0oCon3July2013.Soilmoistureconditionsmattertofarmerswhendecidingwhentoundertakefieldoperations.Wetweatherdelaysdrillingatthestartoftheautumnandinthespring.Afterawetspellthereis

alwaysthetemptationtogetonthelandanddrillbeforeitisreallysuitable,whichcanriskinferioryieldscomparedwithwaitingforbettersoilconditions.Asanexample,dataatManorFarm,Salle,demonstratetheimpactofleavingthesoiljustanotherday(Figure10)orpreferablytwodaysbeforewheeledortrackedvehiclesrunoverit.Thefigureshowsrapiddryingofthesoilat30-50cmdepthbetween5Februaryand6-7February2013,despitelittlechangeinthemoisturestatusoftheshallowerlayers.Asfarmequipmenthasbecomeheavier,thistypeofinformationhasaddedsignificanceinattemptingtoavoidcompactioninthedeepersoillayers.Contact:KevinHiscock([email protected])

Figure10:Soilmoisturestatus(expressedasascalefrequencyunitorpercentvolume)atManorFarm,Salle,3-8February2013.

Figure9:Recordofsoilmoisturecontentat30cm(greenline),60cm(darkblueline)and90cm(lightblueline)depthatManorFarm,Salle,fromFebruarytoearlyJuly2013.Theredlinerepresentssoiltemperatureat75cmdepth.Thesoilmoisturedatarangefrom32-59%andthetemperaturedatarangefrom4-13oC.

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LastPost–fromBobHarrisThisisthelastDTCnewsletterthatIshallbeputtingtogether,thetaskpassingtotheWensumDTCConsortiumfor2016(contact:AndrewLovett).I’vereallyenjoyedmy6+yearsworkingwithDefra,theDTCConsortiaandthewiderrelatedresearchandstakeholdergroups.Theearlydayswereexcitingwiththeemergenceofnewpoliticalwilltodevelop‘catchmentthinking’andaddressthechallengesofmoreintegratedorholisticapproachestoscientificresearchandenvironmentalmanagement.However,thesupportedconceptofalong-termresearchplatformtobuildknowledgeandtestpracticalmeasuresinarobustscientificwaywasalwaysgoingtobechallenging,andsoit’sturnedout,compoundednowbytheserecenttimesofeconomicconstraint.Unfortunatelyaswelearnmoreaboutthecomplexitiesofundertakingresearchatthecatchmentscale(especiallythechallengesofscalingupfromplot,fieldandfarmwheretheexperimentsinevitablyhavetobeundertaken,towholecatchmentsandlandscapes)themorewerealisethattheanswerstobothpolicyandoperationalquestionscannotbeansweredquickly.StormDesmondhasalsorecentlydemonstratedthatthelonger-andshorter-termclimaticchanges,betheyinduced(climatechangerelated)ornatural(ElNinoandNAtlanticOscillationrelated),maywellswamptherelativelysmallwaterqualitychangesinourriversandgroundwaterthatfarm-scalemeasurescanbring.So,manyuncertaintiesremainnottheleastthefeelingthatsmall-scaleon-farmmeasureswillbeinsufficienttoaddressthechallengesfacingwaterqualityandthesubsequentstressesonfreshwaterecosystems–wemaynotbeable‘tohaveourcakeandeatittoo’throughacontinuationofwithamodifiedbusiness-as-usualapproach.Largerlandusechangemaybenecessarytohaltthedeclineinourfreshwaterbiodiversity…Ifthisisapriorityofsociety.Whatevertheapproachandthesolutionsweneedtohavetheresearchcapabilitytoinvestigatethequestionsposedwhetherbypolicy-makers,catchment-managersorlandmanagers.Withoutknowledge,andtheabilitytouseitintelligentlyinmoreintegratedways,wewillcontinuetofumbleinthedark!

And a Happy New Year to all