The ‘Limestone Coast Project’ by Larry Mitchell follows on from his ‘1 Degree Centigrade Project’. The aim is to document the ongoing impact of climate change with a collection of large-scale paintings capturing a moment in history of the Swan Coastal Plain and beyond.
Limestone forms our coastline from the Capes, Caves and Islands such as the Abrolhos. Covering over a quarter of West Australia’s coastline Larry is fascinated by the flow of BIOLOGY becoming ECOLOGY becoming CULTURE…
BIOLOGY - molluscs, tiny organisms such as clams and snails in the ocean have an important role in the formation of limestone.
Limestone is a sedimentary rock composed mainly of calcium carbonate. This is formed when organisms excrete the remains of calcium rich molluscs onto the ocean floor. As molluscs. die, their shells accumulate over time to form thick layers of limestone.
Their contributions to the formation of limestone have significant implications for the earth's geological history and its landscapes.
GEOLOGY - limestone cliffs and coastlines often shaped and modified by weathering, occupy over 4,000km of the West Australian coastline. These forms are constantly in a state of change.
Erosion from wind and water sculpts new landforms such as sea caves, arches and stacks. Acid in rainwater dissolves limestone cliffs and coastlines creating sinkholes and underground cave systems. Plant root systems and burrowing animals breakdown limestone and create rock shelters, niches and contribute to collapsing cliffs.
CULTURE - Western Australia has several limestone quarries for utilisation of limestone as a resource.
Limestone features in construction projects creating arches, pillars and retaining walls. In road building it forms a stable foundation to avoid erosion. In agriculture is improves soil quality and balances pH levels. In water treatment it neutralises acidic water and removes impurities. It is important for the production of cement, steel and other industrial products.
THE FUTURE
There is serious concern that the rising acidity level of the sea will have a significant impact on molluscs and other marine organisms.
When molluscs are exposed to acidic water it becomes difficult for them to maintain their shells and skeletons and in extreme cases, they can be completely dissolved having a significant negative impact on the survival of their species.
The impact of ocean acidification on molluscs can have far reaching consequences for marine ecosystems. Therefore, it is crucial to monitor and mitigate the impacts of ocean acidification on marine organisms and their habitats.
Larry’s project captures this moment in the history of West Australia’s limestone. They form a permanent record in the constantly changing landscape and drawn attention to the risks we are facing resulting from climate change.