UAE coastline changes have a ripple effect
DUBAI // Villa compounds, towers and hotels, marinas and ports, desalination and power plants – the past few decades have seen dramatic changes as increasing numbers of developments have sprung up along the coastline.
But as the competition for space by the sea intensifies, scientists are warning that the cumulative impact of development is negatively affecting valuable coastal and marine ecosystems.
Changes along the coastline have significance even for people who do not live on the coast directly, said Dr Mohammed Yagoub, associate professor of remote sensing and GIS at UAE University.
“Even people living inland are affected by what happens in the coastal zone,” he said, giving the example of the reliance on desalinated water.
Coastal areas and the sea also provide people with food and act as carbon sinks.
Dr Yagoub has been studying land-use changes in Abu Dhabi using satellite imagery. The method, he said, allows him to follow the progression of changes over time as well as study areas hard to access by foot or car.
Through the images he can see where and when expanses of water are in-filled to extend the coastline or create islands, or whether vegetation is being lost. The images also provide some clues as to the impact of desalination plants, which in the UAE largely rely on thermal technologies heating up sea water to produce potable water, then releasing the hot brine back into the ocean.
The streams of water with higher temperature than the ambient are easy to see on the satellite images, said Dr Yagoub, although he has not studied the issue in detail.
In 2006, Dr Yagoub and a colleague published a paper documenting the coastal changes in Abu Dhabi from 1972 to 2000, looking at developments up to 30 kilometres inland. The paper estimated that, within that period, woody vegetation such as mangroves declined from 122sq km to 27sq km. Wetlands were reduced from 432sq km to 168sq km.
Dr Yagoub is studying changes in the area around Yas Island, from 1993 to 2013. The full results will be available next year, he said, but preliminary data suggests a reduction of 11 per cent in the area previously taken up by water, suggesting reclamation activity.
Built-up areas have increased three times within the same period, while vegetation has increased 134 per cent, mostly as a result of new landscaping.
This process is not limited to the capital or even the UAE, said Dr John Burt, associate professor of biology at New York University –Abu Dhabi and head of the Marine Biology Laboratory at the university. In September this year, Dr Burt published a paper on the subject: The Environmental Costs of Coastal Urbanisation in the Arabian Gulf.
More than 85 per cent of people in the Gulf live within 100km of the coast and in several countries in the region, man-made structures occupy more than 40 per cent of the shoreline. The Gulf is one of the most highly impacted marine areas in the world.
“Although sustainable development has been an area of growth in the Gulf in recent years, much of the discourse has focused on improved building standards and urban planning practices with the underlying motivation being cost reduction, economic efficiency and social benefits, while the preservation of natural ecological resources has been under-represented,” the paper says.
Coastal ecosystems – salt marshes, mudflats, salt flats popularly known as sabkhas, and mangrove forests, as well as algal beds, seagrass meadows and coral reefs – are the most important natural assets of the region, the paper argues. While in the UAE awareness is rising about the value of habitats such as coral reefs or mangroves, few people realise the conservation value of less picturesque habitats such as salt flats and mudflats.
“Sabkhas are drawing increasing attention for conservation, but we are still a very long way from putting thought into action,” said Dr Burt. “Channelisation and building of roads across sabkhas changes the underground hydrodynamics, resulting in impacts that can extend hundreds of metres or even kilometres from the development, causing widespread degradation.
“Similar changes are happening in mudflats,” he said. “However, both of these systems are highly productive in terms of supplying energy to the surrounding marine systems and in supporting below-surface diversity, and it’s important that research be implemented to increase our understanding and awareness of these under-appreciated systems.”
Dr Burt is particularly focused on studying coral reefs, something he has done for a decade in the UAE. In the early 2000s he saw recovery from large-scale coral bleaching events due to the El Niño Southern Oscillation, a cyclical periodic shift in the Pacific Ocean, which affects weather around the world. Since then, he has witnessed “large scale degradation in some areas, mainly as a result of coastal development”.
While the UAE is “among one of the most progressive leaders in environmental conservation in the Gulf”, there is still a long way to go, he said.
“Improved awareness in the public and, in particular, with the leadership of the UAE would be essential to promoting the conservation of these systems, but we also require improvements in technical training, enhancement of policy and legislation on coastal zone use, and more stringent environmental and social impact assessment protocols to become leaders in coastal conservation in the Gulf,” said Dr Burt.
“This will take time, but every marathon starts with a single step, and the UAE has an opportunity to lead this race,” he said.
Updated: December 21, 2014 04:00 AM