Limited capacity to retain phosphorus in the Baltic proper offshore sediments
Comment to: Stigebrandt, A. 2018: On the response of the Baltic proper to changes of the total phosphorus supply. Ambio 47: 31–44. https://doi.org/10.1007/s13280-017-0933-7.
Based on calculations using a phosphorus (P) budget model, Stigebrandt (2018) concludes that the P-concentration in the water column of the Baltic proper (BP) could be reduced by about 70% within 10–15 years if the deep bottoms were oxygenated. The calculations assume an annual influx from the sediment to the water column of almost 100 000 tonnes, which could be switched off if the sediments were oxidised. However, the P storage capacity is strictly limited to the uppermost oxidised layers of the sediment cores. Below the sediment redox cline, the total P-concentration levels out around 1000 mg kg−1 dw regardless of the oxygen conditions in the upper sediment layer (Rydin et al. 2011; Malmaeus et al. 2012; Puttonen et al. 2015). The maximum capacity of BP sediments to retain P from recent settling matter would be...
- Jonsson, P., R. Carman, and F. Wulff. 1990. Laminated sediments in the Baltic: A tool for evaluating nutrient mass balances. Ambio 19: 152–158.Google Scholar
- Malmaeus, J.M., E. Rydin, P. Jonsson, D. Lindgren, and O.M. Karlsson. 2012. Estimating the amount of mobile phosphorus in Baltic coastal soft sediments of central Sweden. Boreal Environmental Research 17: 425–436.Google Scholar
- Malmaeus, J.M., and O.M. Karlsson. 2016. Comparing the phosphorus regime in soft sediments from two sub-systems of the Baltic Sea with different redox conditions. VATTEN: Journal of Water Management and Research 72: 31–40.Google Scholar