Bailey-Watts, A.E.

Kirika, A.A.

English

NERC Open Research Archive

   Chapter (non‐refereed)   Bailey­Watts, A.E.; Kirika, A.A.. 1986 Amount of phosphorous entering Loch Leven. In: Annual Report of the Institute of Terrestrial Ecology 1985/86. NERC/ITE, 79­80.   Copyright © 1986 NERC  This version available at http://nora.nerc.ac.uk/10314/    NERC has developed NORA to enable users to access research outputs wholly or partially funded by NERC. Copyright and other rights for material on this site are retained by the authors and/or other rights owners. Users should read the terms and conditions of use of this material at http://nora.nerc.ac.uk/policies.html#access    If you wish to cite this item please use the reference above or cite the NORA entry                        Contact CEH NORA team at  nora@ceh.ac.uk Harriman, R, Morrison, B R S, Caines,L A, Collen, P and  Watt,  A W.  1987. Longterm changes in fish populations of acidstreams and lochs in Galloway.  WaterAir and Soil Pollut,  32,89-112.Pierce,  B A.  1985. Acid tolerance inamphibians.  Bioscience,  35, 239-243.Tome, M A and Pough, F H. 1982.Responses of amphibians to acidprecipitation. In:  Acid rain fisheries,edited by T A Haines and RE Johnson,84-91. Bethesda MD: AmericanFisheries Society.•.50+•.0013.00+2.50;2.00;1.50+1.00;0.50+----0.00F  0.0. 2.0 4.0 __ 6.0 0.0 10.0M  T W Th F Sa Sun1555.0ayFigure 10.  Total P concentrations (pg I ', plotted onlogo, scale) on different days of the week from Januaryto October 1985, in a major inflow to Loch Leven,which receives industrial effluent.n.02,10;2.20;1.00;1.60;1.40+1,20;1.00;0 .In,. total P.L505,0  to.  PI-,ZAP•+1, • •J.1.10Mama+50 twn3.310.0Figure 11.  A comparison between total Pconcentrations (pg 1 -I plotted on log,o scale) above(Nc) and below (Na) an outfall of treated sewage on amajor feeder stream to Loch Leven, January-October1985.Amount of Phosphorus EnteringLoch LevenIntensive ecological surveillance ofLoch Leven, since the late 1960s,indicates that phosphorus (P) is ofspecial importance in theeutrophication of the loch and to the%SRP %PP.s."0 10020de20100 00 20  %SURP 100SRPSURPHaPPNbFigure 12.  Triangular plots of contrastingproportions of soluble reactive P (SRP), solubleunreactive P (SURP), and particulate P (PP), in a smallsilty stream (Ha) and a major river affected by sewageeffluent (Nb) flowing into Loch Leven.growth of its plankton (Bailey-Watts1979, 1981; Bailey-Watts et al. 1983).Recent interest in P levels hasarisen because of a continuingdeterioration in water quality ofsome of the inflows and of the lochitself. Concern over this trend hasbeen expressed by official bodies,including the Nature ConservancyCouncil (NCC), which manages theloch as a National Nature Reserve,and the Forth River PurificationBoard (FRPB), which is responsiblefor water quality in the catchment ofthe loch, and by downstreamindustrial abstractors of water fromthe loch.As summarized by Bailey-Watts andKirika (1984), the interest led to adesk study commissioned by NCCto assess (i) the likely current (then1982-83) loading of P to the loch, (ii)the various contributions to the totalinput, and (iii) implications for theircontrol. The study took account ofanalytical results from an earlierloading assessment made by theDepartment of Agriculture andFisheries for Scotland (DAFS)(Holden 1976; Holden & Caines 1974,unpublished data to 1978), andinformation on nutrient content,obtained by ITE between 1980 and1983. The exercise concluded that,whilst point sources continued tocontribute the major part of the totalloading (as found by the earlierstudy), new measurements werenecessary to establish the actualquantities currently involved. First,the sewer-served population in theloch catchment had increased,giving a higher input from sewagetreatment works. Second, recentanalyses of a major feeder streamreceiving P-rich industrial effluentindicated that the input from thissource had increased considérablysince the late 1970s. Third, P inputsin rain falling directly on the lochsurface were likely to be lower thanoriginally thought. Fourth, moredata were needed to estimate themore diffuse sources of P, such as inrunoff from agricultural land and inwildfowl faeces. Each of theseaspects is now being studied in anew project funded by DAFS, NCC,the Scottish DevelopmentDepartment and the TaysideRegional Council (with a grant from-the Commission of European -Communities). The major part of thework involves sampling all inflowsto the loch, as well as the loch itself,at 8-day intervals throughout acalendar year (Bailey-Watts &Kirika 1987). An 8-day schedule was79•adopted because it was suspected -that some water courses receiveeffluent whose chemistry varieswith day of the week. This suspicionis justified by results from a major -inflow receiving industrial P wate(Figure 10); concentrations of Pwere considerably higher on •Tuesdays to Fridays than on otherdays, especially Sundays. Theimpact of effluent from sewagetreatment works on P levels inanother river was alsoconsiderable. Figure 11 shows that, •despite dilution of effluent by the .river, the concentrationsdownstream of the discharge werevery much greater than'background' levels upstream.The above examples refer to total P,but our analyses also take accountof the particulate and dissolvedfractions. The proportions ofparticulate P, soluble reactive P,and soluble unreactive P varyseasonally within a stream andbetween different streams. Figure12 contrasts a small stream (Ha), richin particulates from road drainage,with a larger river (Nb), which isrelatively richer in dissolved P frofiitreated sewage.Although P is the main focus of thestudy, water from the mouths ofvarious streams was also analyzed •for levels of nitrate and dissolvedsilica. The programme is integratedwith FRPB work defining the height-discharge characteristics of theinflows, so that nutrientconcentrations can be converted to . 1•,!.loadings (ie the products of flow '-and concentration) by relatingcontinuous and spot recordings ofriver heights to chemicalconcentrations. As well as theseasonal surveillance, a number ofintensive 24-hour studies are beingmade to assess variations betweennight and day. Other sub-projects •focus on external inputs of P in (i)rainwater, (ii) wildfowl faeces, and',80(iii) selected agricultural areas, andon internal source P, namely thatderived by recycling of the nutrientfrom the sediments of the loch itself.A E Bailey-Watts and A KirikaReferencesBailey-Watts, A E.  1979. Aspects ofplankton ecology.  Annu. Rep. Inst. terr.Ecol. 1978,  79-80.Bailey-Watts, A E.  1981. Loch Levenplankton succession.  Annu. Rep. Inst.terr. Ecol. 1980,  88-92.Bailey-Watts, A E  &  Kirika, A.  1984.Eutrophication of Loch Leven.  Annu.Rep. Inst. terr. Ecol. 1983,  19-21.Bailey-Watts, A E and Kirilca, A. 1987.A re-assessment of phosphorus inputs toLoch Leven (Kinross, Scotland):rationale and an overview of results oninstantaneous loadings with specialreference to run-off.  Trans. R. Soc.Edinb:  Earth Sciences,  78,  351-367.Bailey-Watts, A E, Jones, D J, May, L. &Kirika, A.  1983. The plankton ecology ofLoch Leven.  Annu. Rep. Inst. terr. Ecol.1982,  14-19.Holden, AV.  1976. The relativeimportance of agricultural fertilizers asa source of nitrogen and phosphorus toLoch Leven.  Tech. Bull. Minist. Agric.Fish Fd.,  32,  306-314.Holden, AV.  &  Caines, L A.  1974.Nutrient chemistry of Loch Leven,Kinross.  Proc. R. Soc. Edinb.  B.,  74, 81-100.Rehabilitation of DisturbedEcosystemsCreating Attractive Grasslands(This work is supported by NatureConservancy Council funds)Much of the stimulus for research onthe creation of plant communitieshas come from the need to restoreor revegetate areas of derelict landleft by mining and quarryingindustries in the developedcountries, notably in Britain,America and Australia. A recentreview (Bradshaw & Chadwick1980) gives an account of progressin this particular area of research,where special problems, such asextremes of temperature, acidityand alkalinity, high salinity andmetal toxicities, or shortage ofwater and nutrients, have beenencountered. Much less attentionhas been given to establishinggrasslands which contain a range ofcolourful forbs on land whereextremes of soil and waterconditions do not prevail.It has been estimated by the NatureConservancy Council (Anon 1984)that 95% of all lowland herb-richgrassland and about 80% oflowland chalk and limestonegrasslands have been destroyedsince 1949, largely by conversion toarable land. While the defence ofthe best remaining areas ofgrassland is clearly a primaryobjective of nature conservation, itis nonetheless now appreciated thatgrasslands and meadows createdby sowing mixtures of grasses anddicotyledons may have an importantrole in conserving wildlife in thecountryside as a whole.Opportunities for creatingattractive grasslands arewidespread. They occur when newverges are made on motorways ortrunk roads; in urban areas in newtowns, such as Milton Keynes,Peterborough and Warrington; innewly created Country Parks; in thegrounds of schools and colleges,where the functional use of grassmay be combined with an educativerole; on the banks and surrounds ofpublic reservoirs and on newlymade farm reservoirs; on farms andestates where the owners or tenantswish to create a more attractiveenvironment and to encouragewildlife.Methods Available for EstablishingAttractive GrasslandsIn theory, there are 5 ways in whichgrasslands can be establishedincorporating wild flowers andnative grasses:1. by natural colonization of baresoil from local or nearby seedsources;2. by spreadin4 top soil containingthe seed of grassland species;3. by transplanting turf fromspecies-rich grassland whichoverlies areas that are to bedestroyed by quarrying or road-making;4. by sowing grass/herb mixturesinto prepared seed beds;5. by diversifying establishedswards, using either the slot-seeding technique, or insertingpot-grown plants with a bulbplanter.In practice, methods (1), (2) and (3)have a number of undesirablefeatures which ensure that they arerarely used, or considered for use,except in special circumstances.Natural colonization depends on theability of propagules to reach a site.As semi-natural habitats becomeincreasingly fragmented anddispersed, the probability of seedarriving at a site becomes low, evenfor those species with an effectivemeans of dispersal, seeds of manygrassland species have nodispersal mechanism and are shedwithin one metre of the motherplants, so the probability of theirreaching sites miles away  is  verysmall. Natural colonization  is  a slowprocess, and the engineer andlandscape architect often require avegetation cover quickly.Spreading top soil in the hope thatit contains the seeds of grasslandspecies is not acceptable, asexperience has shown that the seedbank consists mostly of weeds ofarable land, particularly membersof the Polygonaceae, Cruciferaeand Compositae. Furthermore, topsoil is a variable commodity, and itis extremely difficult to determineor predict the type of vegetation thatwill result when it is spread and notseeded.Turf transplants, obtained bystripping the turf from areas beforethey are quarried, have been usedsuccessfully to revegetate restoredland after quarrying (Gilbert &Wathern 1980). This method doesnot increase the area of grassland,but does save a valuable resourceand is to be encouraged, althoughthe area of land involved is verysmall.The principal means of establishinggrass/wild flower mixtures is eitherby sowing seed mixtures intoprepared seed beds, or bydiversifying existing grasslands.Some results from experiments toinvestigate these methods in moredetail are discussed below.Establishment of Grass/HerbMixtures From SeedThe following are the mainrequirements for successfulestablishment from seed.i)  Careful selection of speciessuitable for the ecologicalconditions of the site.  The mixturessuggested by Wells et al. (1981) forclay, chalk and alluvial soils providea guide as to the most suitablespecies for those soil types. Criteria'used in selecting species forinclusion in these mixtures aregiven in Table 4.ii)  A weed-free seed bed.  It isessential that perennial weeds suchas common couch (Agropyronrepens), docks  (Rumex,  spp.) andcommon nettle  (Urtica dioica) arekilled before sowing by using aherbicide, such as glyphosate,according to the manufacturer'sinstructions.Table 4. Some criteria used for selecting species for inclusion in wild flower seed mixtures1. Ecologically suitable for particular soil/water conditions2. Common grassland species3. Not rare or locally distributed4. Preferably perennial and long-lived5. With colourful and attractive flowers6. Attractive to insects as nectar or pollen sources7. Not highly competitive or invasive8. Seed germinates easily over a range of temperatures

Amount of phosphorous entering Loch Leven

http://nora.nerc.ac.uk/10314/1/858607.pdf

Amount of phosphorous entering Loch Leven

Abstract

Similar works

Full text

Available Versions

NERC Open Research Archive