Abstract
Gradients in nutrient distributions and the effects of eutrophication are common features in most coastal marine areas. These structures occur in aquatic systems due to spatial differences in hydrography,nutrient loading and key biogeochemical processes. Two statistical methods, cluster analysis and probability mapping, have been used in the present study to determine characteristics and patterns in water quality variables. Combined, these two methods provide a useful tool to statistically determine spatial homogeneity and representativity of areas and stations. A case study is presented here in which water quality variables (salinity, dissolved inorganic nitrogen, dissolved inorganic phosphorus and chlorophyll) in surface waters of the Kattegat are analysed for the time period 1993–1997. It was found that morphology, the proximity to sources of nutrient loading from land, nutrient uptake and the infrequent water exchange between the Baltic Sea in the south and the Skagerrak in the north all contribute to create distinct regions of water quality. Regions with concentrations significantly different from the overall mean are identified. In addition to identification of regions with similar characteristics, representative stations (as well as not representative stations) for the respective regions were made. This type of information can be used to design new or revise old monitoring programs.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Ærtebjerg, G. J., Carstensen, D., Conley, K., Dahl, J., Hansen, A., Josefson, H., Kaas, S., Markager, T. G., Nielsen, B., Rasmussen, D., Krause-Jensen, O., Hertel, H., Skov, and Svendsen, L.: 1998, 'Marine områder. Åbne farvande-status over miljøtilstand, årsagssammenhænge og udvikling', Danish Ministry of the Environment, Rapport Nr. 254, Roskilde, Denmark (in Danish).
Andersson, L.: 1996, 'Trends in nutrient and oxygen concentrations in the Skagerrak-Kattegat', J. Sea Res. 35(1-3), 63–71.
Andersson, L. and Rydberg, L.: 1993, 'Exchange of water and nutrients between the Skagerrak and the Kattegat', Estuar. Coast. Shelf Sci. 36, 159–181.
Andersson, L. and Rydberg, L.: 1988, 'Trends in nutrient and oxygen conditions within the Kattegat: Effects of local nutrient supply', Estuar. Coast. Shelf Sci. 26: 559–579.
Asman, W. A. H. and Larsen, S. E.: 1996, 'Atmopheric Processes', in B. Jørgensen, and K.
Richardson (eds), Eutrophication in Coastal Marine Ecosystems, American Geophysical Union, Washington D.C., pp. 21–50.
Borum, J.: 1996, 'Shallow Waters and Land/sea Boundaries', in B. Jørgensen and K. Richardson (eds), Eutrophication in Coastal Marine Ecosystems, American Geophysical Union, Washington D.C., pp. 179–203.
Christensen, P., Møhlenberg, F., Lund-Hansen, L., Borum, J., Christiansen, C., Larsen, S., Hansen, M., Andersen, J. and Kirkegaard, J.: 1998, 'The Danish Marine Environment: Has Action Improved its State?', Ministry of Environment and Energy, Danish EPA, Reports from the HAV90 Marine Research Programme, No. 62, pp. 120.
Christiansen, C., Gertz, F., Laima, M. J. C., Lund-Hansen, L., Vang, T. and Jörgensen, C.: 1997, 'Nutrient (P, N) dynamics in the southwestern Kattegat Scandinavia: Sedimentation and resuspension effects', Environ. Geol. 29, 66–77.
Cloern, J.: 2001, 'Our evolving conceptual model of the coastal eutrophication problem', Marine Ecol. Progr. Ser. 29, 280–329.
Conley, D. J., Kaas, H., Møhlenberg, F., Rassmussen, B. and Windolf, J.: 2000, 'Characteristics of Danish estuaries', Estuaries 23, 820–837.
Conley, D. J. and Josefson, A. B.: 2001, 'Hypoxia, Nutrient Management and Restoration in Danish Waters', in N. N. Rabalais and R. E. Turner (eds), Coastal Hypoxia: Consequences for Living Resources and Ecosystems, Coastal and Estuarine Studies 58, American Geophysical Union, Washington, D.C., pp. 425–434.
Conley, D. J., Markager, S., Andersen, J., Ellermann, T. and Svendsen, L. M.: 2002, 'Coastal eutrophication and the Danish National Aquatic Monitoring and Assessment Program', Estuaries 25, 706–719.
Choynowski, M.: 1959, 'Maps based on probabilities', J. Amer. Statist. Assoc. 54, 385–388.
Cressie, N. and Read, T. R.: 1985, 'Do sudden infant deaths come in clusters?', Statist. Decisions 2, 333–349.
Cressie, N. and Read, T.R.: 1989, 'Spatial data analysis of regional counts', Biometr. J. 31, 699–719.
Danielsson, Å., Cato, I., Carman, R. and Rahm, L.: 1999, 'Spatial clustering of metals in the sediments of Skagerrak/Kattegat', Appl. Geochem. 14, 689–706.
Floderus, S. and Pihl, L.: 1989, 'Resuspension in the Kattegat: Impact of variation in wind climate and fishery', Estuar. Coast. Shelf Sci. 31, 487–498.
Granéli, E., Wallström, K., Larsson, U., Granéli, W. and Elmgren, R.: 1990, 'Nutrient limitation of primary production in the Baltic Sea area', Ambio 19, 142–151.
Gustafsson, B.: 2000, 'Time-dependent modeling of the Baltic entrance area. 1. Quantification of circulation and residence times in the Kattegat and the straits of the Baltic sill', Estuaries 23, 231–252.
Hansen, I. S., Ærtebjerg, G. and Richardson, K.: 1995, 'A scenario analysis of effects of reduced nitrogen input on oxygen conditions in the Kattegat and the Belt Sea', Ophelia 42, 75–93.
HELCOM: 1984, 'Guidelines for the Baltic Monitoring Programme for the second stage', Baltic Sea Environ. Proc. 12, 1–249.
HELCOM: 1996, 'Third Periodic Assessment of the State of the Marine Environment of the Baltic Sea 1989-1993; Background document', Baltic Sea Environ. Proc. 64B, 252.
HELCOM: 1998, 'Third Baltic Sea Pollution Load Compilation', Baltic Sea Environ. Proc. 70, 134.
Howarth, R., Billen, G., Swaney, D., Townsend, A., Joworski, N., Lajtha, K., Downing, J., Elmgren, R., Caraco, N., Jordan, T., Berendse, F., Freney, J., Kudeyarov, V., Murdoch, P. and Zhao-Liang, Z.: 1996, 'Regional nitrogen budgets and riverine N and P fluxes for the drainages to the North Atlantic Ocean: Natural and human influences', Biogeochem. 35, 75–139.
Iversen, T. M., Grant, R. and Nielsen, K.: 1998, 'Nitrogen enrichment of European inland and marine waters with special attention to Danish policy measures', Environ. Poll. 102, 771–780.
Jensen, H. S., Mortensen, P. B., Andersen, F. Ö., Rasmussen, E. and Jensen, A.: 1995, 'Phosphorus cycling in a coastal marine sediment, Aarhus bay', Limnol. Oceanogr. 40, 908–917.
Jørgensen, B. and Richardson, K.: 1996, 'Eutrophication: Definition, History and Effects', in B. Jørgensen and K. Richardson (eds), Eutrophication in Coastal Marine Ecosystems, American Geophysical Union, Washington D.C., pp. 1–19.
Kiørboe, T.: 1996, 'Material Flux in the Water Column', in B. Jørgensen and K. Richardson (eds), Eutrophication in Coastal Marine Ecosystems, American Geophysical Union, Washington D.C., pp. 67–94.
Kronvang, B., Ærtebjerg, G., Grant, R., Kristensen, P., Hovmand M. and Kirkegaard, J.: 1993, 'Nationwide monitoring of nutrients and their ecological effects: State of the Danish Aquatic Enviroment', Ambio 22, 176–187.
Madsen, P. F. and Larsen, B.: 1986, 'Accumulation of Mud Sediments and Trace Metals in the Kattegat and the Belt Sea', Rep. Marine Pollution Lab. 10, Charlottenlund Denmark, 68 pp.
Maestrini, S. Y. and Granéli, E.: 1991, 'Environmental conditions and ecophysiological mechanisms which led to the 1988 Chrysochromulina polylepis bloom: An hypothesis', Oceanol. Acta 14, 397–413.
Pedersen, F. B.: 1993, 'Fronts in the Kattegat: The hydrodynamic regulation factor for biology', Estuaries 16, 104–112.
Pedersen, M. F. and Borum, J.: 1995, 'Phosphorus Recycling in the Seagrass Zostera Marina', in Olsen & Olsen, Biology and Ecology of Shallow Coastal Waters, Fredensborg, Denmark, pp. 45-52.
Richardson, K. and Heilmann, J. P.: 1995, 'Primary production in the Kattegat: Past and present', Ophelia 41, 317–328.
Rosenberg, R., Elmgren, R., Fleischer, S., Jonsson, P., Persson, G. and Dahlin, H.: 1990, 'Marine eutrophication case studies in Sweden', Ambio 19, 102–108.
Rydberg, L., Edler, L., Floderus, S. and Granéli, W.: 1990, 'Interaction between supply of nutrients, primary production, sedimentation and oxygen consumption in SE Kattegat', Ambio 19(3), 134–141.
Sandén, P. and Danielsson, Å.: 1995, 'Spatial properties of nutrient concentrations in the Baltic', Environ. Monit. Assess. 34, 278–307.
Sharma, S.: 1996, Applied Multivariate Techniques, John Wiley & Sons, New York, 493 pp.
Stigebrandt, A.: 1983, 'A model for the exchange of water and salt between the Baltic and the Skagerrak', J. Phys. Oceanograp. 13, 411–427.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Danielsson, Å., Rahm, L., Conley, D.J. et al. Identification of Characteristic Regions and Representative Stations: A Study of Water Quality Variables in the Kattegat. Environ Monit Assess 90, 203–224 (2004). https://doi.org/10.1023/B:EMAS.0000003590.58753.0e
Issue Date:
DOI: https://doi.org/10.1023/B:EMAS.0000003590.58753.0e