Across the region, many countries have been rightfully alarmed by China's accelerated construction activities across the South China Sea, which are tantamount to building "facts on the waters" amid unresolved territorial disputes.
In response, United States President Barack Obama has criticised what many countries see as China "using its sheer size and muscle to force countries into subordinate positions".
The construction activities do not only violate the spirit of the 2002 Declaration on the Conduct of Parties in the South China Sea, which discourages claimant countries from unilaterally altering the status quo through provocative actions, but also run counter to the United Nations Convention on the Law of the Sea (Unclos), which bars coastal states from artificially transforming disputed features.
An often neglected aspect of the South China Sea disputes, however, is the environmental impact of ongoing construction activities and large-scale fishing by disputing parties.
As signatories to the Convention on Biological Diversity and Unclos, South China Sea claimant states have the obligation to ensure their territorial jostling does not come at the expense of the delicate ecological balance in the disputed waters.
To be fair, China is not the only country that has been engaged in building structures and placing people and soldiers on disputed features.
Occupying the two biggest naturally formed features in the Spratlys, the Philippines and Taiwan have built airstrips and advanced facilities on Thitu and Itu Aba islands, respectively.
Vietnam, which controls the most features in the area, has built various forms of structures across the Spratly chain of islands.
Malaysia has also built advanced infrastructure on Swallow Reef and, similar to Vietnam, has been actively engaged in hydrocarbon exploration in the South China Sea.
China's construction activities, however, stand out in terms of technological sophistication, scale and sheer speed.
Within a few months, China has altered the nature of disputed features beyond recognition.
Deploying state-of-the-art geo- engineering technology, China has transformed Fiery Cross, Mischief, Gaven and Johnson South reefs, among other low-tide elevations and rocks in the Spratlys.
No longer a reef, Fiery Cross is now an island, having been artificially enlarged by 11 times over its original size, and stands as the biggest feature in the area.
China's neighbours are particularly concerned that Fiery Cross, which hosts about 200 troops, will soon be transformed into a command-and-control headquarters for expanded and sustained Chinese air, naval and paramilitary patrols in disputed waters.
China could soon also deploy missile defence and radar systems to the area.
China has effectively established the skeleton of an air defence identification zone in the South China Sea, which could pose a threat to freedom of navigation and overflight in the area.
This would enable China to drive out other claimant states from the Spratlys by tightening the noose around their supply lines.
Of course, China maintains that its activities are perfectly consistent with its "inherent and indisputable sovereignty" over much of the South China Sea.
It has also raised "environmental protection" and "fishery production service" among the core objectives of its ongoing construction activities.
Claimant states such as the Philippines, however, have accused China of damaging up to 121ha of coral reefs, allegedly leading to "irreversible and widespread damage to the biodiversity and ecological balance".
The Philippine authorities claim China's dredging activities are damaging coral reefs - a rich breeding ground for high-value fisheries - which will cost neighbouring states up to US$100 million (S$133 million) annually.
In response to China's construction activities, the Philippines and other claimants, including Taiwan, have continued with refurbishing their facilities and expanding surveillance across disputed waters, further complicating the disputes and expanding the coastal real estate boom in the South China Sea.
Growing patrols by regional and extra-regional naval vessels have also come at the expense of the environment. In recent years, the Philippines' Tubbataha Reef Natural Park, a Unesco World Heritage Site, has been damaged by American (the USS Guardian) and Chinese vessels which precariously navigated the South China Sea.
Illegal, under-reported and unregulated (IUU) fishing is another major source of concern, gravely affecting fishery resources in the South China Sea. ASEAN countries such as Indonesia and the Philippines have been victims of over- exploitation and large-scale illegal fishing and poaching of endangered species such as sea turtles, often involving foreign fishing vessels from China and Vietnam.
By some estimates, 70 per cent of coral reefs in the South China Sea have already been adversely affected by a combination of mechanical accidents, pollution and unsound fishing practices.
Given China's continued and growing reliance on fishermen- cum-militia forces to push its claims across the South China Sea, the IIU conundrum will most likely intensify.
As the pre-eminent platform for multilateral co-operation in the region, ASEAN should play an important role in facilitating greater co-operation and laying down the foundations of an environmental regime in the South China Sea.
Mutually-agreed-upon rules and regulations on protecting marine life should either be a major element of any Code of Conduct or a separate bilateral agreement between ASEAN and China. After all, 2015 is supposed to mark the year of "ASEAN-China maritime co-operation".
Unabated illegal and large- scale fishing, coupled with ecologically damaging construction activities, represent a direct threat to the lives of tens of millions of people across the region, who depend on the South China Sea for their livelihood and daily dietary needs.
Across the world, from the Northern Pacific to the North Sea, and the Baltic to the Mediterranean and even the Yellow Sea, countries have been negotiating various mechanisms to preserve endangered species and protect marine life within areas of overlapping claims.
Given the growing urgency of the environmental issue, it is high time for China and other claimant states to honour their obligations under international treaties and begin negotiating various mechanisms, including a moratorium on fishing and construction in certain areas, to protect the tenuous ecological balance in the South China Sea. The future of the region is at stake.
The writer is a political science professor at De La Salle University in the Philippines.
This article was first published on May 7, 2015.
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