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Chapter 4 Ecosystems (PDF) ECOSYSTEMS4 Coordinating Lead Authors: Mario V. Balzan (Malta), Abed El Rahman Hassoun (Lebanon) Lead Authors: Najet Aroua (Algeria), Virginie Baldy (France), Magda Bou Dagher (Lebanon), Cristina Branquinho (Portugal), Jean-Claude Dutay (France), Monia El Bour (Tunisia), Frédéric Médail (France), Meryem Mojtahid (Morocco/France), Alejandra Morán-Ordóñez (Spain), Pier Paolo Roggero (Italy), Sergio Rossi Heras (Italy), Bertrand Schatz (France), Ioannis N. Vogiatzakis (Cyprus), George N. Zaimes (Greece), Patrizia Ziveri (Spain) Contributing Authors: Marie Abboud-Abi Saab (Lebanon), Aitor Ameztegui (Spain), Margaretha Breil (Italy), Thierry Gauquelin (France), llse R. Geijzendorffer (France), Aristeidis Koutroulis (Greece), Jürg Luterbacher (Germany), Mohammad Merheb (Lebanon), Cesar Terrer Moreno (Spain), Marco Turco (Spain), Elena Xoplaki (Germany) This chapter should be cited as: Balzan MV, Hassoun AER, Aroua N, Baldy V, Bou Dagher M, Branquinho C, Dutay J-C, El Bour M, Médail F, Mojtahid M, Morán-Ordóñez A, Roggero PP, Rossi Heras S, Schatz B, Vogiatzakis IN, Zaimes GN, Ziveri P 2020 Ecosystems. In: Climate and Environmental Change in the Mediterranean Basin – Current Situation and Risks for the Future. First Mediterranean Assessment Report [Cramer W, Guiot J, Marini K (eds.)] Union for the Mediterranean, Plan Bleu, UNEP/MAP, Marseille, France, pp. 323-468. 324 CLIMATE AND ENVIRONMENTAL CHANGE IN THE MEDITERRANEAN BASIN | MedECC CHAPTER 4 - ECOSYSTEMS Table of contents 4 Ecosystems 328 Executive summary ........................................................................................................................................................................... 328 4.1 Marine ecosystems ........................................................................................................................................................................... 329 4.1.1 Current condition and past trends ........................................................................................................................... 329 4.1.1.1 Observed changes ................................................................................................................................................. 329 Key habitats undergoing change ................................................................................................................... 331 - Coralligenous ........................................................................................................................................................... 331 - Deep sea ecosystems ...........................................................................................................................................332 - Planktonic ecosystems ......................................................................................................................................... 333 - Large vertebrates ................................................................................................................................................... 335 Changes in biodiversity ....................................................................................................................................... 335 4.1.1.2 Past changes ............................................................................................................................................................ 339 Response of marine ecosystems to past temperature changes ........................................................339 Response of marine ecosystems to past changes in stratifcation and ventilation . 340 Response of marine ecosystems to past changes in productivity .....................................................341 Response of marine ecosystems to past changes in pH ................................................................. 341 4.1.2 Projected vulnerabilities and risks .......................................................................................................................... 342 4.1.2.1 Projected impacts and risks ............................................................................................................................ 342 Projected impacts on microbes ..................................................................................................................... 342 Projected impacts on primary and secondary production .............................................................342 Projected impacts on macrobenthic and pelagic species .............................................................. 344 - Corals..........................................................................................................................................................................344 - Seagrass .................................................................................................................................................................... 345 - Mussels ...................................................................................................................................................................... 346 - Jellyfsh ......................................................................................................................................................................346 Winners and losers ............................................................................................................................................... 346 4.1.2.2 Vulnerabilities .......................................................................................................................................................... 347 Climate-related vulnerabilities ...................................................................................................................... 347 Anthropogenic vulnerabilities ......................................................................................................................... 348 4.1.3 Adaptation ................................................................................................................................................................................. 348 4.1.3.1 Long-term monitoring and adaptation strategies ..............................................................................348 4.1.3.2 The role of Marine Protected Areas (MPAs) for adaptation ........................................................... 348 4.1.3.3 Management of fsheries and adaptation ................................................................................................349 4.1.3.4 Adaptation strategies for ocean warming and ocean acidifcation in the Mediterranean Sea .................................................................................................................................350 4.1.3.5 Regional observation networks as a tool for adaptation ................................................................. 351 4.2 Coastal ecosystems .......................................................................................................................................................................... 352 4.2.1 Current condition and past trends ........................................................................................................................... 352 4.2.1.1 Observed changes ................................................................................................................................................. 352 Natural Mediterranean habitats under severe degradation ......................................................... 352 - Sandy beaches and sand dunes ........................................................................................................................ 353 - Rocky coasts ............................................................................................................................................................. 354 - Coastal wetlands .................................................................................................................................................... 355 - Seagrass meadows ................................................................................................................................................ 355 - Coastal lagoons and deltas ................................................................................................................................. 356 - Salt marshes ............................................................................................................................................................ 357 CLIMATE AND ENVIRONMENTAL CHANGE IN THE MEDITERRANEAN BASIN | MedECC 325 CHAPTER 4 - ECOSYSTEMS - Coastal aquifers ...................................................................................................................................................... 358 Risks from non-indigenous species ............................................................................................................ 358 - Phytoplankton .......................................................................................................................................................... 358 - Jellyfsh ...................................................................................................................................................................... 359 - Fish .............................................................................................................................................................................. 359 - Plants ........................................................................................................................................................................
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