MarClim: Marine Biodiversity and Climate Change
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The MarClim project examined the effects of climatic warming on marine biodiversity by examining selected indicator species. The project used historic time series data, from the 1950s onwards, and contemporary data. Quantitative counts of barnacles, limpets and trochids were made as well as semi-quantitative surveys of up to 56 intertidal taxa. Based on the data, models were created to examine the propagation probability of certain species in different British waters. In combination with future climate scenarios, it was also possible to predict future species ranges and abundances.
The project aimed to use key intertidal species, whose abundances had been shown to fluctuate with changes in climatic conditions, as indicators of changes occurring in the intertidal and open sea zones.
The MarClim project has provided strong evidence that recent rapid climate change has resulted in changes in the abundance, population structure and biogeographic ranges of a number of intertidal indicator species, mirroring changes in the open sea. Experiments have shown that many of the changes in southern/lusitanian species have occurred as a result of increased reproductive output and a higher rate of juvenile survival in response to increased warming. In the case of some northern/boreal species it would appear that decreases in abundance may be linked to a decrease in their reproductive output. Evidence suggests that species range expansion in response to climatic warming is occurring quicker in marine ecosystems (plankton, fish, as well as intertidal species) than in terrestrial ecosystems.
UKCIP02 (see UKCIP)
Marine species such as plankton and fish show rapid responses to alterations in climate. The investigations have shown that the rate at which the biogeographic limits of southern intertidal species are extending northwards and eastwards towards the colder North Sea is up to 50km per decade, far exceeding the global average of 6.1km per decade in terrestrial systems.
Different rates of range extensions and contractions are likely to result in a short-term increase in biodiversity on rocky shores close to the biogeographic boundaries. However, as the climate continues to warm biodiversity is likely to return to previous levels as northern species ranges retract to be replaced by southern species, resulting in different species compositions.
The project has been funded under the auspices of UKCIP by the following institutions:
Marine Biological Associaton, UK
Marine Biological Association of the UK,The Laboratory
Citadel Hill
UK - PL1 2PB Plymouth