<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sandberg, J.</style></author><author><style face="normal" font="default" size="100%">Elmgren, R</style></author><author><style face="normal" font="default" size="100%">Wulff, F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Carbon flows in Baltic Sea food webs -- a re-evaluation using a mass balance approach</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Marine Systems</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Mar. Syst.</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">ANE,</style></keyword><keyword><style  face="normal" font="default" size="100%">ANE, Baltic Sea,</style></keyword><keyword><style  face="normal" font="default" size="100%">ANE, Baltic Sea, Bothnia Gulf</style></keyword><keyword><style  face="normal" font="default" size="100%">Baltic Sea</style></keyword><keyword><style  face="normal" font="default" size="100%">biogeochemical cycle</style></keyword><keyword><style  face="normal" font="default" size="100%">biomass</style></keyword><keyword><style  face="normal" font="default" size="100%">Bothnia Gulf, Bothnian Bay</style></keyword><keyword><style  face="normal" font="default" size="100%">Brackish</style></keyword><keyword><style  face="normal" font="default" size="100%">Carbon cycle</style></keyword><keyword><style  face="normal" font="default" size="100%">Chemical oceanography</style></keyword><keyword><style  face="normal" font="default" size="100%">Community composition</style></keyword><keyword><style  face="normal" font="default" size="100%">Computer analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">ECOSYSTEMS</style></keyword><keyword><style  face="normal" font="default" size="100%">food webs</style></keyword><keyword><style  face="normal" font="default" size="100%">Marginal seas</style></keyword><keyword><style  face="normal" font="default" size="100%">Mass</style></keyword><keyword><style  face="normal" font="default" size="100%">O 1080 Multi-disciplinary</style></keyword><keyword><style  face="normal" font="default" size="100%">Organic carbon</style></keyword><keyword><style  face="normal" font="default" size="100%">phytoplankton</style></keyword><keyword><style  face="normal" font="default" size="100%">plankton</style></keyword><keyword><style  face="normal" font="default" size="100%">Q1 01482 Ecosystems and energetics</style></keyword><keyword><style  face="normal" font="default" size="100%">studies</style></keyword><keyword><style  face="normal" font="default" size="100%">transfer</style></keyword><keyword><style  face="normal" font="default" size="100%">trophic relationships</style></keyword><keyword><style  face="normal" font="default" size="100%">trophic structure</style></keyword><keyword><style  face="normal" font="default" size="100%">Trophodynamic cycle</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2000</style></year><pub-dates><date><style  face="normal" font="default" size="100%">Jul</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">3-4</style></number><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">249-260</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The brackish Baltic Sea has been seen as particularly suitable for studies of food webs. Compared to fully marine ecosystems, it has low species diversity, which means fewer trophic linkages to analyse. The Baltic Sea is also one of the best-studied areas of the world, suggesting that most data requirements for food web models should be fulfilled. Nevertheless, the influence of physical and biological factors on trophic interactions and biogeochemical patterns varies spatially in the Baltic Sea, adding considerable complexity to food web studies. Food web structure and processes can be described and compared quantitatively between areas by estimating the flow of matter or energy through the organisms. Most such models have been based on carbon, though studies of complementary flows of other elements limiting production, such as nitrogen and phosphorus would be desirable. However, since ratios between carbon and other elements are used in calculating these flows, it is crucial, as a first step, to quantify the flows of carbon as accurately as possible. In this study, we used the EcopathII software (ver 3.1) to analyse models of carbon flow through the food webs in the three main areas of the Baltic Sea; the Baltic proper, Bothnian Sea and Bothnian Bay. A previously published study on carbon flow in the Baltic Sea (Elmgren, R. 1984) was complemented with the data on respiration and flow to detritus (Wulff, F., Ulanowicz, R. 1989) in order to present complete mass balance models of carbon. The purpose of re-evaluating previous models with new analytic tools was to check how well their carbon flows balance, and to provide a basis for improved mass balance models using more recent data, including nutrients other than carbon. The resulting mass balance networks for the Baltic proper, Bothnian Sea and the Bothnian Bay were shown to deviate from steady state. There was an organic carbon surplus of 45, 25 and 18 g C m super(-2) year super(-1) in the pelagic zones of the Baltic proper, Bothnian Sea and Bothnian Bay, respectively. The Ecopath network analysis confirmed that the overall carbon flow was highest in the Baltic proper, somewhat lower in the Bothnian Sea and much lower in the Bothnian Bay. The only clear differences in food web structure between the basins was that the average trophic level was lower for demersal fish in the Bothnian Sea and higher for macrofauna in the Bothnian Bay, compared to the other basins. The analysis showed weakness in our current understanding in Baltic Sea food webs and highlighted areas where improvements could be made with more recent data.</style></abstract><accession-num><style face="normal" font="default" size="100%">4772436</style></accession-num><notes><style face="normal" font="default" size="100%">Special Issue: The Changing Coastal Oceans: From Assessment to Prediction.English</style></notes><auth-address><style face="normal" font="default" size="100%">Department of Systems Ecology, Stockholm University, S-10691 Stockholm, Sweden; E-mail: johannes@system.ecology.su.se</style></auth-address></record></records></xml>