Abstract
Critical loads have become a well-establishedpart of the work programme of the UnitedNations Economic Commission for Europe (UNECE) Conventionon Long-Range Transboundary Air Pollution (CLRTAP). Thelinking of ecosystem response to deposition level is thecentral principal of the critical loads approach. Foreach ecosystem, a biological indicator is chosen, asuitable chemical criterion selected and a criticalchemical limit assigned. The Bc:Al ratio is the mostwidely used chemical criterion for setting criticalloads. However, critical loads based on this criterionare very sensitive to marine deposition. In regions whichreceive high depositions of marine-derived base cations,such as the Republic of Ireland (ROI) and the UnitedKingdom (UK), critical loads based on the Bc:Al criterionwill inevitably be high. Therefore, it is proposed thatcritical loads are estimated using multiple chemicalcriteria with appropriate critical limits to protect thechosen biological indicators. The range of publishedchemical criteria have been applied to the ROI and theUK. The chemical criterion corresponding to the mostsensitive critical load have been mapped and thecontribution of each to the final maps investigated. Thesimulations indicate that the most sensitive criteria forsetting critical loads are based on specifying critical Hor Al concentrations. However, the choice of critical limits andmodel parameters will ultimately effect the criticalloads. Therefore, it is important that appropriate criticallimits are chosen to protect the biological indicator andreceptor ecosystem from long-term damage.
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Cosby, B.J., Hornberger, G.M. and Galloway, J.N.: 1985, 'Modelling the effects of acid deposition: assessment of a lumped parameter model of soil water and stream water chemistry', Wat. Resour. Res. 21, 51-63.
Davies, T.D., Trainer, M., Wigington, P.J. and Eshleman, K.N.: 1992, 'Acidic episodes in surface waters in Europe', J. Hydrol. 132, 25-69.
Hettelingh, J.-P, Downing, R.J. and de Smet, P.A.M. (eds): 1991, 'Mapping Critical Loads for Europe: CCE Technical Report No. 1', RIVM Report No. 259101001, RIVM, Bilthoven, The Netherlands, 86 pp.
Hornung, M., Sutton, M.A. and Wilson, R.B. (eds): 1995, 'Mapping and Modelling of Critical Loads for Nitrogen: A Workshop Report', Institute of Terrestrial Ecology, U.K., 207 pp.
Løkke, H., Bak, J., Falkengren-Grerup, U., Finlay, R.D., Ilvesniemi, H., Nygaard, P.H. and Starr, M.: 1996, 'Critical Loads of Acidic Deposition for Forest Soils: is the Current Approach Adequate?', Ambio 25, 510-516.
Posch, M., de Smet, P.A.M., Hettelingh, J.-P. and Downing, R.J. (eds): 1995, 'Calculation and Mapping of Critical Thresholds in Europe: Status Report 1995', RIVM Report No. 259101004, RIVM, Bilthoven, The Netherlands, 198 pp.
Posch, M., de Smet, P.A.M., Hettelingh, J.-P. and Downing, R.J. (eds): 1999, 'Calculation and Mapping of Critical Thresholds in Europe: Status Report 1999', RIVM Report No. 259101009, RIVM, Bilthoven, The Netherlands, 165 pp.
Reuss, J.O. and Johnson, D.W.: 1986, Acid Deposition and the Acidification of Soils and Waters, Springer-Verlag, New York, 120 pp.
Reuss, J.O., Christophersen, N. and Seip, H.M.: 1986, 'A critique of models for freshwater and soil acidification', Water, Air, and Soil Pollut. 30, 909-930.
Schecher, W.D. and Driscoll, C.T.: 1987, 'An evaluation of uncertainty associated with aluminium equilibrium calculations', Wat. Resour. Res. 23, 525-534.
Sverdrup, H. and de Vries, W.: 1994, 'Calculating critical loads for acidity with the simple mass balance method', Water, Air, and Soil Pollut. 72, 143-162.
Sverdrup, H. and Warfvinge, P.: 1993, 'The Effect of Soil Acidification on the Growth of Trees, Grass and Herbs as expressed by the (Ca+Mg+K)/Al ratio', Reports in Ecology and Environmental Engineering 1993:2, Department of Chemical Engineering II, Lund University, Sweden, 177 pp.
Sverdrup, H., de Vries, W. and Henriksen, A.: 1990, 'Mapping Critical Loads', Miljörapport 1990:14, Nordic Council of Ministers, Copenhagen, 124 pp.
Ulrich, B.: 1983, 'Interaction of Forest Canopies with Atmospheric Constituents: SO2, Alkali and Earth Alkali Cations and Chloride', in B. Ulrich and J. Pankrath (eds), Effects of Accumulation of Air Pollutants in Forest Ecosystems, pp. 33-45. Reidel, Dordrecht, The Netherlands, 389 pp.
Ulrich, B.: 1987, 'Stability, Elasticity and Resilience of Terrestrial Ecosystems with Respect to Matter Balance', in E.D. Schulze and H. Zwolfer (eds), Potentials and Limitations of Ecosystem Analysis, Ecological Studies 61, pp. 11-49, Springer-Verlag, Berlin.
Werner, B. and Spranger, T. (eds): 1996, 'Manual on Methodologies and Criteria for Mapping Critical Levels/Loads and Geographical Areas where they are Exceeded', Federal Environmental Agency (Umweltbundesamt), Berlin, Germany, 144 pp.
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Aherne, J., Farrell, E.P., Hall, J. et al. Using Multiple Chemical Criteria for Critical Loads of Acidity in Maritime Regions. Water, Air, & Soil Pollution: Focus 1, 75–90 (2001). https://doi.org/10.1023/A:1011578311375
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DOI: https://doi.org/10.1023/A:1011578311375