Difference between revisions of "Effects of global climate change on European marine biodiversity"
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| − | Global warming has a range of | + | Global warming has a range of effects on marine systems. The effects may be related to changing water temperatures, changing water circulation or changing habitat; as a consequence of these changes, altered pathways within biogeochemical cycles and food webs are detected as well. In the first case, the biological responses and impacts result from the physical effects. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> |
| − | Even without human-induced climate change, the biodiversity and | + | Even without human-induced climate change, the biodiversity and biogeography of species is continuously changing (seasonal and yearly changes). Consequently, long term monitoring is necessary in order to evaluate these processes. The marine systems however may become more dynamic and variable due to climate change. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> |
| − | Europe may be less threatened by sea-level rise than many developing country regions. However, coastal ecosystems do appear to be threatened, especially enclosed seas such as the Baltic, Mediterranean and Black Sea. These seas have only small and primarily east-west orientated movement corridors, which may restrict northward displacement of | + | Europe may be less threatened by sea-level rise than many developing country regions. However, coastal ecosystems do appear to be threatened, especially enclosed seas such as the Baltic, the Mediterranean and the Black Sea. These seas have only small and primarily east-west orientated movement corridors, which may restrict northward displacement of organisms in these areas. <ref name="Nicholls"> Nicholls, R.J.; Klein,R.J.T. (2005). Climate change and coastal management on Europe's coast, '''in''': Vermaat, J.E. ''et al.'' (Ed.) (2005). Managing European coasts: past, present and future. pp. 199-226.</ref> |
==Effects on primary production== | ==Effects on primary production== | ||
| − | Higher temperatures and enhanced stratification could affect the | + | Higher temperatures and enhanced stratification could affect the productivity of phytoplankton. A number of models predict an increase in global primary production of between 1% and 8% by 2050, when compared to pre-industrial times (SAMIENTO 2004 cit in 1) |
| − | + | Because phytoplankton is an important basis of the marine food web, any change in the timing, abundance or species composition of the phytoplankton will have an effect on the whole food web. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> | |
| − | Because phytoplankton is | ||
==Effects on the recruitment process== | ==Effects on the recruitment process== | ||
| − | The population dynamics of a lot of marine vertebrates and fish are driven by recruitment processes. | + | The population dynamics of a lot of marine vertebrates and fish are driven by recruitment processes. The recruitment of cold temperate species is often synchronized with seasonal production cycles of phytoplankton. Increasing sea water temperatures may advance the timing of reproduction of these fish species; this may result in a mismatch with their food source (phytoplankton) (match/mismatch hypothesis). A change in recruitment success will lead to shifts in species composition. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> |
===Example: cod recruitment in the North Sea=== | ===Example: cod recruitment in the North Sea=== | ||
| − | The Atlantic cod recruitment in the North Sea, in the past 40 years, was influenced by changes at the base of the food web (bottom-up-control), induced by rise of temperature. Cod recruitment decreased from the mid-1980s, coincident with unfavorable changes in the plankton ecosystem. <ref name="Beaugrand"> Beaugrand, G.; Brander, K.M.; Lindley, J.A.; Souissi, S.; Reid, P.C. (2003). Plankton effect on cod recruitment in the North Sea.''Nature (Lond.) 426(6967)'': 661-664.</ref> Fig 1 | + | The Atlantic cod (''Gadus morhua'') recruitment in the North Sea, in the past 40 years, was influenced by changes at the base of the food web (bottom-up-control), induced by the rise of temperature. Cod recruitment decreased from the mid-1980s, coincident with unfavorable changes in the plankton ecosystem. <ref name="Beaugrand"> Beaugrand, G.; Brander, K.M.; Lindley, J.A.; Souissi, S.; Reid, P.C. (2003). Plankton effect on cod recruitment in the North Sea.''Nature (Lond.) 426(6967)'': 661-664.</ref> Fig 1 |
| + | |||
| + | ==Effects on the biogeography== | ||
| + | |||
| + | The species movement in a warming area is towards the poles in general. Since global warming accelerated in the late 1980s, pole ward advances of southern species and retreats of northern species have been recorded in zooplankton, fish and benthic species (Brander et al. 2003; Southward et al. 2005 cit in 1). | ||
| + | The species distribution is not always northwards. For example when the stock of the main prey of the harp seals in the Barents Sea collapsed, these seals migrated southwards along the coast of Norway and into the North Sea in search of food. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> | ||
| + | |||
| + | ===Example: Study of barnacles in the Celtic-Biscay shelf=== | ||
| + | |||
| + | The Celtic-Biscay shelf was liable to warming in the 1930; in the 1960 there was a switch back to colder. Changes in species assemblages were described on rocky shores, using barnacles as a sensitive indicator of wider changes in marine life. (Southward et al. 1995, 2005). These showed switches between warm water barnacles in the 1950s (Chthamalus spp.) to greater dominance by the cold water barnacle Semibalanus balanoides in the 1960s and 1970s. On rocky shores warm water barnacles now exceed the levels found in the 1950s. <ref name="Phillipart"> Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach.'' European Science Foundation, Marine Board: Strasbourg, France.'' 82pp.</ref> (Fig 2) | ||
| + | |||
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Revision as of 17:04, 20 August 2007
Global warming has a range of effects on marine systems. The effects may be related to changing water temperatures, changing water circulation or changing habitat; as a consequence of these changes, altered pathways within biogeochemical cycles and food webs are detected as well. In the first case, the biological responses and impacts result from the physical effects. [1]
Even without human-induced climate change, the biodiversity and biogeography of species is continuously changing (seasonal and yearly changes). Consequently, long term monitoring is necessary in order to evaluate these processes. The marine systems however may become more dynamic and variable due to climate change. [1]
Europe may be less threatened by sea-level rise than many developing country regions. However, coastal ecosystems do appear to be threatened, especially enclosed seas such as the Baltic, the Mediterranean and the Black Sea. These seas have only small and primarily east-west orientated movement corridors, which may restrict northward displacement of organisms in these areas. [2]
Contents
Effects on primary production
Higher temperatures and enhanced stratification could affect the productivity of phytoplankton. A number of models predict an increase in global primary production of between 1% and 8% by 2050, when compared to pre-industrial times (SAMIENTO 2004 cit in 1) Because phytoplankton is an important basis of the marine food web, any change in the timing, abundance or species composition of the phytoplankton will have an effect on the whole food web. [1]
Effects on the recruitment process
The population dynamics of a lot of marine vertebrates and fish are driven by recruitment processes. The recruitment of cold temperate species is often synchronized with seasonal production cycles of phytoplankton. Increasing sea water temperatures may advance the timing of reproduction of these fish species; this may result in a mismatch with their food source (phytoplankton) (match/mismatch hypothesis). A change in recruitment success will lead to shifts in species composition. [1]
Example: cod recruitment in the North Sea
The Atlantic cod (Gadus morhua) recruitment in the North Sea, in the past 40 years, was influenced by changes at the base of the food web (bottom-up-control), induced by the rise of temperature. Cod recruitment decreased from the mid-1980s, coincident with unfavorable changes in the plankton ecosystem. [3] Fig 1
Effects on the biogeography
The species movement in a warming area is towards the poles in general. Since global warming accelerated in the late 1980s, pole ward advances of southern species and retreats of northern species have been recorded in zooplankton, fish and benthic species (Brander et al. 2003; Southward et al. 2005 cit in 1). The species distribution is not always northwards. For example when the stock of the main prey of the harp seals in the Barents Sea collapsed, these seals migrated southwards along the coast of Norway and into the North Sea in search of food. [1]
Example: Study of barnacles in the Celtic-Biscay shelf
The Celtic-Biscay shelf was liable to warming in the 1930; in the 1960 there was a switch back to colder. Changes in species assemblages were described on rocky shores, using barnacles as a sensitive indicator of wider changes in marine life. (Southward et al. 1995, 2005). These showed switches between warm water barnacles in the 1950s (Chthamalus spp.) to greater dominance by the cold water barnacle Semibalanus balanoides in the 1960s and 1970s. On rocky shores warm water barnacles now exceed the levels found in the 1950s. [1] (Fig 2)
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Phillipart C.J.M. (ed.) (2007). Impacts of climate change on the European marine and coastal environment: ecosystems approach. European Science Foundation, Marine Board: Strasbourg, France. 82pp.
- ↑ Nicholls, R.J.; Klein,R.J.T. (2005). Climate change and coastal management on Europe's coast, in: Vermaat, J.E. et al. (Ed.) (2005). Managing European coasts: past, present and future. pp. 199-226.
- ↑ Beaugrand, G.; Brander, K.M.; Lindley, J.A.; Souissi, S.; Reid, P.C. (2003). Plankton effect on cod recruitment in the North Sea.Nature (Lond.) 426(6967): 661-664.
