Publication Abstract

Spatial analysis of heavy metal concentrations in the brown shrimp Crangon crangon (Linnaeus, 1758) from the southern North Sea

Spatial analysis of heavy metal concentrations in the brown shrimp Crangon crangon (Linnaeus, 1758) from the southern North Sea

Kristine Jung, Vanessa Stelzenmüller* and Gerd-Peter Zauke

The spatial distribution of heavy metal concentrations (Cu, Pb, Cd, Ni and Zn) in the brown shrimp Crangon crangon (Linnaeus, 1758) collected on a cruise of FRV “Walther Herwig III" to the southern North Sea in January 2004, has been investigated at an ecological scale of 18 x 18 km to evaluate the range of spatial autocorrelations for the different variables under study and to assess the extent to which biological properties of the organisms may be related to the spatial distribution of metal concentrations in C. crangon from the sampling area. Semivariogram models obtained by geostatistical procedures indicated a distinct increase in variability for most variables with sampling distance. Only if samples are taken at distances above the estimated values for the practical range of the semivariogram, stochastic independence of the data can be assumed. These distances are 6.6 km for Cd, 3.6 km for Cu, 3.0 km for Ni, 5.2 km for Pb, and 3.5 km for Zn. Classical and geostatistical population estimates for the means are in good agreement. Conversely, we observed a reduction of variability for Cd, Ni, Pd and Zn by the application of the geostatistical approach. The contour plots of the mapped spatial distribution revealed a accumulation of heavier brown shrimps in the samples in the south-western corner of the sampling area and a clear coincidence of high values for Cd, Ni and Pb with low shrimp mean body wet weight. Beyond, measured Cu, Pb and Zn concentrations were largely within the reported range, while Cd concentrations in C. crangon from the North Sea were far below the values in decapod crustaceans reported from other regions. We conclude that with this integrated biomonitoring approach heavy metal concentrations could be assessed more precisely and relations between biotic and abiotic variables could be evaluated. Hence, we suggest such an approach also for future studies addressing the problem of trophic transfer of energy or pollutants from food (e.g. brown shrimp) to higher trophic levels like fish and seabirds.

Reference

Kristine Jung, Vanessa Stelzenmüller* and Gerd-Peter Zauke (2009) Spatial analysis of heavy metal concentrations in the brown shrimp Crangon crangon (Linnaeus, 1758) from the southern North Sea. Scientia Marina, 73 (1): 105-115

Kristine Jung, Vanessa Stelzenmüller* and Gerd-Peter Zauke

Scientia Marina, 73 (1): 105-115