Horrill, A.D.

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CST REPORTNg?77VEGETATIONCHANGESON CESSATIONOF GRAZING. MONITORINGBRYOPHYTESIN HORROWDALE. INTERIMREPORTS 1975/76. 3 leaves. fCoricractTitle: Monitoring'yeChangesin Woodlands; Contractor: ITE (A.D.Horrill); NCC ResearchContract: F3/03/273Key-Words: BORROWDALE; BRYOPHYTES, GRAZING; GRIZEDALEThis Report is an officialdocumentpreparedunder contractbetween the NatureConservancyCouncil and the NaturalEnvironment ResearchCouncil. It shouldnot be quoted without permissionfrom both the Instituteof TerrestrialEcolouy ,and the Nature ConservancyCouncil.ITB 15EE2E9ss ReE2ELVEGETATIONCHANGES ON CESSATIONOF GRAZINGThe aim of this project is to assess the changes in two sites in the LakeDistrictwhen grazing pressuresare removed. Several recordingmethods arebeing used and the objectiveis to assesstheir value in terms of each of.use,time taken to perform fieldwork, and the usefulnessand detail of the dataobtained..AThe sites used are in oak woodland in Borrowdaleand Grizedale. TheBorrowdalesite is in heavily sheep-grazedwoodlandrich in atlanticbryophyteswhilst the Grizedalearea is dominatedby heavily grazedVacciniumonly a few incheshigh, the main grazing animalbeing Red deer.Both areas were chosen as those where changewas likely to occur over ashort timescale.BorrowdaleThe experimentalplot has been fenced againstsheep and 10 randomlydistributed1 a? quadrats set up inside the enclosure. As there hadpreviouslybeen problems with the unauthorizedremovalof marker stakesthe quadratshave been marked with 8" lengthsof 1" x 1" aluminiumangle drivenverticallyinto the ground. Two stakes are located at oppositecornersof the quadraton a diagonaland serve to relocatethe quadrat frame.The quickestand most practicalway of findingthese markershas been foundto be by means of a metal detectorwhich is very effectiveproviding tilevegetationis not wet with dew or rain.Recordingat this site has only been carriedout for one year prior tofencing due to the marker loss. Two techniquesare being used, photographicrecordilvgand freqUencycounts using a subdividedquadrat.The photographicrecords are taken in both monochromeandcolour,using astandard50 mm lens. The camera is mountedon a tripod above the quadrat,aligned using a spirit level and the camera/grounddistanceis standardisedfor each quadrat.2The quadratframe used for the recordinghas been sub-dividedinto 2520 x 20 cm sub-quadratsand within each of these all speciesof floweringplants, ferns and bryophytesare recordedon a presence/absencebasis. Itis proposedthat any tree seedlingsthatdevelop in subsequentyears willbe individuallylabelledwith numberedtags and height measurementstaken.GrizedaleThe area in Grizedale is on ForestryCommissionland and has experiencednoproblemswith interference. Two year's recordshave been obtainedpriOr tofencing.The plot layoutand marking system are the same as describedfor Borrowdaleexcept that the fence heighthas to be sufficientto excludethe Red deerwhich frequentthe area.Recordingwork is being carriedout photographicallyas at Borrowdalebothin monochromeand colour.The secondmethod of recordingused at Grizedaleis point quadrats. 7norder to relocatethe samplepoints accurately,a non-randomlayout for thepoint quadratshas been adopted. A metre rule is pinned down along one sideof the quadrat and a point quadrat framewith 10 pins is set at rightangles to the rule. This is repeatedat 2 cm intervalsalong the rule,yieldinga total of 500 points -perquadrat. During the descentof thepins all contactswith the vegel_ationare recorded. Computerprogrammeshave been writtenwhich summarisethe resultsin terms of percentagecover,percentagecontributionto the sward and percentagebare ground orlitter.It is anticipatedthat a least three years recording followingfencingwillbe needed at these two sitesbefore an assessmentof the techniquesused canbe made.A. D. Morrill 19 March 1976.rrE16 PROGRESSREPORTVANITORINGBRYOFHITES IN BORROaDALEThe main objectiveof this work is to assessthe possibilityof developinga quick photographictechniquefor recordingchange in bryophytecommurities.The area chosen foi,the work,i% Johnny's wood,Borrowdale,a site well knownamongst bryologistsfor the range and diversityof its AtlanticbryophyteCommunities. In the first instancesazicolouscommunitiesare being recorded,the techniquedeveloped so far being as follows:-The areas recordedare chosenon the grounds of their species content andthe availabilityof a site for mounting the recordingcamera. Once chosenthe site is relatedto nearby landmarksand marked by a small paint spot;the area used ie generally of the order of 30 x 20 cm. The camera is mountedin a small cradlewhich enables the centre of the lens to be moved 5 am ina horizontalplane by slidingthe camera body from side to side,this cradlefits onto the head of a standardheavy duty tripod.Once set up the system is focusedand so positionedthat the marker spotis visible in the corner of the field of view, the lens/subjectdistanceis then recordedfor future reference. The first exposure is made, thecamera moved,alongthe cradle and the secondphotographtaken.Both natural light and electrcnicflash has been used in preliminarytrials;natural light has proved to be far the most satisfactoryprovidinga camerawith an adequaterange of slow shutter speeds is available. The electronicflash tends to give rather harsh results even using a diffuser.By mounting the pairs of transparenciesunder a standard stereoscopea verygood impressionof depth is obtainedeven with such small subjects.Assessmentmethods in the process of trial includesuperimpositionof standardgrids over the transparenciesand projectionin order to detectchanses andthe preparationof "vegetationmaps" of each areaused. At the presenttime 25 sites are in coursr,of 1-.eingrecordedin Johnny's Wood.It is anticipatedthat at least3-5years recordin2;will be needed to obtainmeaningfulresults although from a practicalpoint of view the field techniqueappears quick and yields satisfactoryresults.

Monitoring of changes in woodlands. Vegetation changes on cessation of grazing. Monitoring bryophytes in Borrowdale. Interim reports 1975-76

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Monitoring of changes in woodlands. Vegetation changes on cessation of grazing. Monitoring bryophytes in Borrowdale. Interim reports 1975-76

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