The Xisha Islands in the South China Sea. Image: Xinhua
In the last three decades, China has seen staggering economic growth, but it's come at a cost. A swelling middle class has increased demand for energy needs, like coal and natural gas, and has put increasing amounts of pressure on environmental resources. The oceans aren't immune, either: A new study says that Chinese coral abundance has declined by 80 percent in the last 30 years, and coastal development, pollution, and overfishing are to blame.
The research, published in Conservation Biology, comes from the Australian Research Council Centre of Excellence for Coral Reef Studies, and shows the results of a survey of reefs off the coast of mainland China and in the South China Sea. The main driver the authors attributed to the loss was economic growth. That finding is supported by a recent WWF study that suggest China is using its environmental resources more than twice as fast as is sustainable.
"China's ongoing economic expansion has exacerbated many wicked environmental problems, including widespread habitat loss due to coastal development, unsustainable levels of fishing and pollution," the reef study authors wrote.
In the South China Sea, where reefs expand across a region of more than 12,000 square miles, the authors found another problem: In many cases, waters and islands are claimed by multiple countries–parts of the Spratly Islands are claimed by six different nations–which exacerbates the pollution and overfishing problem while also making meaningful conservation efforts nearly impossible.
"On offshore atolls and archipelagos claimed by six countries in the South China Sea, coral cover has declined from an average of greater than 60 percent to around 20 percent within the past 10-15 years," the authors wrote.
While climate change and warming waters are thought to increase the risk of coral bleaching events, the study found that more direct human causes–the usual trio of development, pollution and overfishing–had more of a negative impact on the reefs. Meanwhile, a few token efforts at opening marine parks and protecting waters have done little to help stem the decline.
“So far, climate change has affected these reefs far less than coastal development, pollution, overfishing, and destructive fishing practices," the authors wrote. "Ironically, these widespread declines in the condition of reefs are unfolding as China’s research and reef-management capacity are rapidly expanding.”
We've already seen a couple high-profile studies showing coral reef decline this year. One took a historical look at the Great Barrier Reef in Australia, and found that pollution has been wrecking reefs for more than 80 years, and that polluted waters had caused a shift in the type of coral inhabiting the Great Barrier Reef, a switch that makes the entire reef more vulnerable. The other showed that Caribbean reefs are pretty much dead, thanks to destructive human activities like mismanaged tourism, pollution, and overfishing, all of which weakened reefs to the point that they're much more prone to bleaching as waters warm.
The common thread is that nearly all major reef systems worldwide are seeing massive declines due to human activity. Those declines also lead to a decline in biodiversity, and will change the makeup of the reefs to be less resilient. So as waters continue to warm, weakened reefs stand less of a chance of even surviving.
That's a massive problem as tropical waters are the lifeblood of many tropical nations. Reef systems are extremely important biodiversity sinks that are also key indicators of ecosystem health as a whole, and if they collapse, the fisheries millions of people rely on will as well. We're not over the cliff just yet, but the window for conservation is slamming shut. When nearly every major reef system in the world has been shown to be in decline, the outlook for ocean health is not good.