In this WP the aim is not to develop models as they already exist (the NEST model system), but to analyze the model outputs in relation to
a) the inertia of the system (as a measure of resilience) and
b) the same early warning indicators mentioned in WP1.
The state-of-the-art inertia approach provides a measure of how fast the system will react to a change for example in management.
Aim of the WP
Here we explore in detail the inertia and stability of three major sub-systems of the Baltic Sea that have undergone documented radical shifts in the past, i.e. the catchment (river loads of nutrients and carbon), the deep water realm of the Baltic Sea (rapid spreading of dead zones) and marine food web structure (collapsing fish stocks).
Resilience and non-linearities
External forcing (climate change and anthropogenic impacts) vs. internal feedbacks and pools in all three subsystems may explain the non-linear responses and abrupt changes within these subsystems of the Baltic Sea ecosystem.
We may express the inertia of the watersheds and the deep water realm as the capacity to sequester external nutrient loads. We will address changes in resilience by simulating the response of nutrient leakage, retention and nutrient fluxes as a function of external loading.
The resilience of the food web can be described by the analysis of the strength of species interactions and their feedbacks buffering external disturbances.
This WP investigates potential regime shifts and thresholds in various subsystems of the Baltic Sea, i.e. the catchment generating nutrient loads, the marine basins with their temporal and spatial nutrient and oxygen regimes in the water and in the sediments, and the food web as a responsive system to bottom up (salinity, temperature, nutrients, oxygen) and top down (fishery, seabird and seal predation) effects.
- Eriksson Hägg, H., S.W. Lyon, T. Wällstedt, C.-M. Mörth, B. Claremar, C. Humborg. 2013. Future Nutrient Load Scenarios for the Baltic Sea Due to Climate and Lifestyle Changes, Ambio, DOI 10.1007/s13280-013-0416-4.
- Gustafsson, B., F. Schenk, T. Blenckner, K. Eilola, H. Meier, B. Müller-Karulis, T. Neumann, T. Ruoho-Airola, O. Savchuk & E. Zorita. 2012. Reconstructing the Development of Baltic Sea Eutrophication 1850–2006. Ambio 41, 534-548.
- Gårdmark, A., M. Lindegren, S. Neuenfeldt, T. Blenckner, O. Heikinheimo, B. Müller-Karulis, S. Niiranen, M. T. Tomczak, E. Aro, and A. Wikström. 2013. Biological ensemble modeling to evaluate potential futures of living marine resources. Ecological Applications 23:742-754.
- Lassalle, G., J. Lobry, F. Le Loc'h, S. Mackinson, F. Sanchez, M. T. Tomczak, and N. Niquil. 2013. Ecosystem status and functioning: searching for rules of thumb using an intersite comparison of food-web models of Northeast Atlantic continental shelves. ICES Journal of Marine Science: Journal du Conseil 70:135-149.
- MacKenzie, B. R., H. M. Meier, M. Lindegren, S. Neuenfeldt, M. Eero, T. Blenckner, M. T. Tomczak, and S. Niiranen. 2012. Impact of climate change on fish population dynamics in the baltic sea: a dynamical downscaling investigation. Ambio 41:626-636.
- Meier, H. E. M., H. C. Andersson, B. Arheimer, T. Blenckner, B. Chubarenko, C. Donnelly, K. Eilola, B. G. Gustafsson, A. Hansson, J. Havenhand, A. Höglund, I. Kuznetsov, B. R. MacKenzie, B. Müller-Karulis, T. Neumann, S. Niiranen, J. Piwowarczyk, U. Raudsepp, M. Reckermann, T. Ruoho-Airola, O. P. Savchuk, F. Schenk, S. Schimanke, G. Väli, J.-M. Weslawski & E. Zorita. 2012. Comparing reconstructed past variations and future projections of the Baltic Sea ecosystem—first results from multi-model ensemble simulations. Environmental Research Letters 7:034005.
- Müller-Karulis, B., Arula, T., Balode, M., Laur, K., Ojaveer, E, 2013, Challenges and opportunities of local fisheries management: Pikeperch, Sander lucioperca (Actinoptergygii: Perciformes: Percidae), in Pärnu Bay, Northern Gulf of Riga, Baltic Sea. Acta Ichthyologica et Piscatoria, Vol. 43, pp 151-161.
- Möllmann, C., M. Lindegren, T. Blenckner, L. Bergström, M. Casini, R. Diekmann, J. Flinkman, B. Müller-Karulis, S. Neuenfeldt, J. O. Schmidt, Tomczak, MTT, J. Voss and A. Gårdmark, 2013. Implementing ecosystem-based fisheries management: from single-species to integrated ecosystem assessment and advice for Baltic Sea fish stocks. ICES Journal of Marine Science: Journal du Conseil:fst123.
- Niiranen, S., T. Blenckner, O. Hjerne, and M. T. Tomczak. 2012. Uncertainties in a Baltic Sea food-web model reveal challenges for future projections. Ambio 41:613-625.
- Niiranen, S., J. Yletyinen, M. T. Tomczak, T. Blenckner, O. Hjerne, B. R. MacKenzie, B. Müller‐Karulis, T. Neumann, and H. Meier. 2013. Combined effects of global climate change and regional ecosystem drivers on an exploited marine food web. Global Change Biology.
- Tomczak, M., S. Niiranen, O. Hjerne, and T. Blenckner. 2012. Ecosystem flow dynamics in the Baltic Proper—Using a multi-trophic dataset as a basis for food–web modelling. Ecological Modelling 230:123-147.
- Tomczak, M.T., J.J. Heymans, J. Yletyinen, S. Niiranen, S.A. Otto, and T. Blenckner. 2013. Ecological network indicators of ecosystem status and change in the Baltic Sea. PLoS ONE 8(10): e75439.
- Österblom, H., A. Merrie, M. Metian, W. J. Boonstra, T. Blenckner, J. R. Watson, R. R. Rykaczewski, Y. Ota, J. L. Sarmiento, and V. Christensen. 2013. Modeling Social–Ecological Scenarios in Marine Systems. BioScience 63:735-744.
- Ustups, D., Müller-Karulis, B., Bergstrom, U., Makarchouk, A., Sics, I. 2013, The influence of environmental conditions on early life stages of flounder (Platichthys flesus) in the central Baltic Sea. Journal of Sea Research, Vol 75. Pp 77-84.
A list of additional publications is available here
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