Biodiversity and conservation, and role of marine protected areas
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Biodiversity is an important value and not always sufficiently considered, given its vital role in the provision of ecosystem goods and services, including fisheries, marine resources, recreation and tourism. There could be greater recognition of biodiversity impacts, and the use of vulnerable coastal and marine ecosystems to monitor, understand and respond to these impacts. There also needs to be an explicit consideration of the interaction between climate change and biodiversity in coastal and marine areas, due to the inherent value of biodiversity, and to support the ecosystem goods and services delivered to local and larger communities.
The sensitivities of coastal and marine ecosystems may be heightened by interactions between human activity and climate change. One example is the links between overfishing, such as documented interactions between overfishing of tuna and turtles, increased jellyfish populations, algal blooms, and warmer sea temperatures in the Mediterranean. Other interactions include those between contaminants and climate change; and the loss of coastal sand dunes, salt marshes and wetlands and increased vulnerability to erosion and extreme weather events.
The Millennium Ecosystem Assessment reports focused on the valuable ecosystem roles and services provided by biodiversity, as well as the human challenges and threats to diverse ecosystems, including climate change. Chapter 10 of the Arctic Climate Impact Assessment Scientific Report focused on the principles of biodiversity conservation in a circumpolar Arctic, including the Scandinavia Arctic, Iceland and Greenland. Aspects of Chapter 10 and the principles of biodiversity conservation are found in a paper commissioned by the Council of Europe, Conserving European Biodiversity in the Context of Climate Change (M Usher, 2005).
Effect of climate change of coastal areas
Coasts, deltas, estuaries, lagoons, enclosed seas, and arctic coasts are vulnerable coastal and marine ecosystems that need to be considered when analyzing the impacts of climate change. Some European examples are the Thames estuary, the Venice lagoon, and the Adriatic, Mediterranean and Baltic Seas. The Arctic Climate Impact Assessment Scientific Report addresses the vulnerability of arctic coasts, its terrestrial and marine species, and local communities. Representative examples of these vulnerable coastal ecosystems could be used as indicators of climate change, and to understand the effectiveness of adaptation and mitigation strategies.
Lagoons, estuaries and deltas, as well as coasts, are all linked to the sea, and have common physical, economic and social characteristics, and impacts and responses to climate change. These low-lying systems are vulnerable to sea level rise, storm surges, extreme weather events, as well as saltwater infiltration and changes to the precipitation regime. For example, Venice and the its lagoon, are vulnerable to extreme weather events and "normal" flooding, which now occurs up to 10 times in one year. Due to human-induced and geological subsidence of the lagoon, as well as overall subsidence of the Adriatic Sea, Venice and the lagoon are vulnerable to even a ten centimetre increase in sea level. They will be dramatically affected by a larger increase in sea level. One measure of the actual adaptive or preventative costs required to protect Venice and the lagoon is the 5.2 billion euro MOSES project, which is a dike structure designed to be used to prevent tidal surges from entering the lagoon. Given the sensitivity of the Venice lagoon to climate change, it could also be considered as a model and indicator for impacts of climate change on lagoons.
Another example, London and the Thames estuary, incorporates the natural, built and urban environment. The estuary is very vulnerable to sea level rise, tidal surges, flooding in the upstream tributaries of the Thames River, and heavy rainfalls. All these factors and the potentially negative impacts have been aggravated by increased building in the flood plains, inadequate sewage and storm water drainage systems, and changes in the built environment such as less green space and more concrete that decrease the absorption of rainfall. Since its construction, the Thames Flood Barrier has been used to reduce the impacts of upstream flooding and tidal surges. The Thames 2100 initiative addresses the additional flood and tidal surge defence mechanisms that will be needed in the near future to address climate influenced sea level rise and extreme weather events. Additionally, significant costs in the amount of 2 to 4 billion pounds will be required to reduce the increasing problem of combined storm water and sewage discharge. These measures and costs could be considered at least in part as costs of adapting to climate change.
Coral reefs and island atolls are considered in any discussion of climate warming, including the EU green paper on adaptation to climate change. Other ecosystems are not as well considered. For example, there is the need to consider the impact of climate change on deep and cold water reefs, and areas of high biological diversity such as sea mounts. Even warm seas like the Mediterranean have deep and cold water reefs. What will be the impacts of temperature rises in seas and biodiversity impacts on these very productive areas? As well as temperature, changing currents and circulation patterns also have to be considered.
The Mediterranean is a highly vulnerable region and sea, due to drought and declining winter precipitation in some regions, particularly in the eastern Aegean and for the countries of northern Africa. Conversely, there is flooding during the winter in other regions, such as southern France and the Adriatic Sea. In some regions, there is a shift from a Mediterranean ecosystems characterized by wet mild winters and hot dry summers to a more tropical ecosystems that is hot and dry year round. As well as these changes, there is extensive coastal development, migration into the region, local and transboundary contaminants, and ecosystem shifts.
Concern over the interaction between biodiversity and climate change has been reflected in the recommendations of the European Platform for Biodiversity Research Strategy, which was introduced to a meeting of EU Nature Ministers in October 2005 (Recommendations on Climate Change and Biodiversity Conservation: Knowledge Needed to Support Development of Integrated Adaptation Strategies, www.epbrs.org). Ongoing work is now underway through an e-conference “Life on a Blue Planet”, which has developed a draft list of research priorities, which were presented at the EPBRS meeting in Porto on November 7 to 9, 2007. Results there will be presented to the EU (www.cimar.org/epbrs).
The overarching theme throughout the “Life on a Blue Planet” e-conference was that integrated monitoring, with a long-term perspective operating on a European scale, would lead to a better understanding of the effects of climate change on marine biodiversity. Though the focus at the meeting was on marine biodiversity, many of the research priorities are equally relevant for terrestrial and aquatic biodiversity.
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