By Henrylito D. Tacio
Fort Lauderdale, Florida — Deforestation is a problem of growing significance all over the world. It is especially acute in tropical countries. To help stem the tide, people are reforesting those degraded areas.
Reforestation is the restocking of existing forests and woodlands which have been depleted. It also refers to afforestation, the process of restoring and recreating areas of woodlands or forest that once existed but were deforested or otherwise removed or destroyed at some point in the past.
In like manner, degraded coral reef ecosystems can also be restored by doing the same technique. Coral reefs are hailed as “tropical rainforests of the seas.” If reforestation can be done in the tropics, it can also be achieved in the seas, according to Dr. Baruch Rinkevich, a senior scientist with the Israel Oceanographic and Limnological Research.
“Many of the world’s coral reefs are experiencing a severe degradation,” said Dr. Rinkevich. These ecologically-fragile marine wonders can be saved by using “branching corals” as “ecosystem engineering species.”
In a press conference during the 11th International Coral Reef Symposium, the Israeli scientist talked about the so-called “gardening coral reefs concept,” a method inspired from forest restoration guidelines.
The technique involves generating and farming large stocks of new coral colonies in a floating nursery which is far from predators and other disturbances. After one year or so, they are transplanted into degraded areas.
“In past efforts, we take coral colonies from healthy localities and transplanted into denuded areas,” Dr. Rinkevich admitted. “This method resulted in low survival rates and inflicted stress on donor coral colonies.”
In their study, they selected five denuded knolls somewhere in Eilat’s Reef in Red Sea. “Eilat’s coral reef is the world’s most northern reef,” said Yael Horoszowski, who doing the study. “This reef, which was classified in the past among the richest and most biodiversed reefs, has been in decline for the past forty years.”
In November 2005, they transplanted 550 nursery-grown colonies of two branching coral species. Three-hundred more colonies were transplanted in May 2007.
During the first two years of monitoring, they observed few of those transplanted corals died. “We also found out that there was an increase of marine species like fish and crabs as we literally brought new ‘homes’ to them,” said Horoszowski.
In Indonesia, Dr. Helen Fox is doing another method of restoring degraded reefs caused by destructive fishing with explosives (dynamite or homemade bombs). The work was done in Komodo National Park. Sustained by rushing currents where the Indian and Pacific Oceans meet, the park is home to a staggering marine biodiversity. To the north, coral reefs sparkle. To the south, manta rays and filter-feeding whales glide through choppy, nutrient-rich waters.
“Blast fishing causes widespread and devastating damage to coral reefs,” said Dr. Fox. “Despite being illegal, blast fishing continues to be a threat to reefs in the national park.”
In restoring the degraded reefs, Dr. Fox and her team used rock piles as “a low-tech, locally-available reef rehabilitation method.” In 2002, they installed four different configurations of rock piles at four sites.
Today, the team observed that the rock piles were able to stabilize the rubble caused by explosives. It also attenuated the water currents, recreated “the three-dimensional structure” of an intact reef, and provided surfaces for coral recruitment and refuges for other marine species.
Although these two methods are very successful in restoring degraded reefs, Dr. Fox reiterated that it is “cheaper and more efficient to prevent the damage in the first place.”
Living coral reefs are the foundation for many marine species, including fish, crabs, oysters, and clams. They also provide extensive recreational and tourism opportunities.
Reef-building corals grow where the water is clear, warm, and shallow. These conditions occur in tropical waters near the equator, on the eastern sides of continents, and around oceanic islands.
In the United States, half of its coral reefs are in trouble. According to the International Union for Conservation of Nature, one third of the world’s coral reefs are threatened with extinction.
In the Indian and Pacific Oceans, coral reefs are dying off much quicker than previously thought, a study shows. Researchers compiled more than 6,000 underwater surveys, which were conducted between 1968 and 2004, in ten sub-regions of the Indo-Pacific. These included Indonesia, the Philippines, and Australia’s Great Barrier Reef.
For the last two decades, Indo-Pacific reefs have shrunk by 1 percent each year – a loss equivalent to nearly 600 square miles (1,553 square kilometers). That makes the rate of reef loss about twice the rate of tropical rain forest loss.
“We have to do something now before we will lose our coral reefs forever,” urged Dr. Rinkevich. “Restoring them using the way tropical forests are rescued is a good start.” — ###
Degraded coral reefs can be restored!
By Henrylito D. Tacio