In Photo: Residents watch as Mayon Volcano spews ash on January 23 as seen from Legazpi City, Albay province. The Philippines’s most active volcano ejected a huge column of lava fragments, ash and smoke in another thunderous explosion at dawn, sending thousands of villagers back to evacuation centers and prompting a warning that a violent eruption may be imminent.
While volcanic eruptions are seen as serious threats to life and property, although often a boon to the local tourism industry, the ashfall, burning lava and lahar are threats to the variety of life that thrives around the volcano.
Plants and animals in forests, caves, rivers and other unique ecosystems surrounding volcanoes may be lost during massive volcanic eruptions.
However, there is no need to worry. Experts say the effect of a volcanic eruption is temporary; the forest will eventually recover naturally, and fast, and wildlife will thrive once more, ensuring that the cycle of life goes on.
Natural disasters like flash floods, landslides, droughts, forest fires, or worse, volcanic eruptions, underscore the need to preserve as many key biodiversity areas as possible to ensure the recovery of degraded ecosystems.
These key biodiversity areas would provide shelter to animal wildlife in the event of disasters and would also become the source of seeds to be dispersed by nature’s best farmers—the birds, the bees and bats—later on.
The Philippines sits on a unique tectonic setting ideal for volcano formation, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
The entire archipelago is surrounded by subducting plates as manifested by the trenches that are related to volcano formation, the Phivolcs, an agency of the Department of Science and Technology, said in its official web site.
There are 24 active and 26 potentially active volcanoes in the Philippines, including Mayon Volcano.
Also known as Mount Mayon, the popular volcano, a world-renowned natural wonder because of its perfect, symmetrical conical shape, is one of the most active volcanoes in the world.
The most destructive eruption of the Mayon Volcano occurred on February 1, 1814, during which volcanic debris—mostly dark ash devastated the town of Cagsawa. The trees around it burned and the rivers that sustain life around it were severely damaged.
Ash accumulated to 9 meters in depth. During the eruption, 1,200 locals in Albay province died, according to Mayon Volcano’s historical records available in various literatures attributed to the accounts of the Phivolcs.
Although deadly, the enchanting volcano is the centerpiece of the Mayon Volcano Natural Park, which covers a total land area of 5,775.7 hectares.
It is first protected as a National Park in 1938 but in 2000 it was reclassified as Natural Park by virtue of Proclamation 412 signed on November 21, 2000.
The volcano is in the province of Albay and is shared by eight cities and municipalities, namely, Camalig, Daraga, Guinobatan, Legazpi City, Ligao City, Tabaco City, Malilipot and Santo Domingo.
The peak of the Mayon Volcano is the highest elevation in the entire Bicol region at 2,462 meters or 8,077 feet.
The Mayon Volcano is a central property of the United Nations Education Scientific and Cultural Organization (Unesco) Albay Biosphere Reserve.
The Mayon Volcano Natural Park (MVNP) is included in the tentative list of Unesco World Heritage Site.
“For its height, unrivaled shape and remarkably symmetrical contours, Mayon Volcano was believed by the pre-Hispanic Bicolanos to be the abode of their ancestors and, thus, its confines were subjected to taboo, including violation of its natural resources and even climbing its peak. It was also held as the sacred mountain of both the deity Mayong and Gugurang, the supreme god of Bicolano animist beliefs,”the Unesco said in its web site.
The beauty of the volcano has inspired local artists, allowing culture and arts to flourish in the region. Because it is active, having erupted over 50 times in the last century, it has caused devastation in surrounding areas.
Nevertheless, its frequent eruption has made people living around it more resilient to natural disasters.
The natural park is home to 156 floral species belonging to 36 families and 83 species of trees, including the single dipterocarp found in the area, locally known as baguatsa or gisok-gisok (Hopea philippinensis); and one near-threatened species from the rare family Nepentheceae, the pitcher plant.
Plant biodiversity found within the park is composed of 71 woody species belonging to 49 genera and 33 families. About 32 percent of these species are endemic, while others are indigenous.
It is a habitat for 104 species of land vertebrates, including 57 species of birds, 10 species of amphibians, 24 species of reptiles and 13 species of mammals.
Of the 13 mammal species, seven are endemic of which three are listed as vulnerable: the Philippine brown deer, Philippine warty pig and giant golden-crowned flying fox.
The bird fauna includes 37 endemic species with three species listed on the International Union for Conservation of Nature (IUCN) red list: the nearly threatened Luzon bleeding heart, vulnerable Philippine eagle-owl and the critically endangered Philippine cockatoo.
The 10 amphibian fauna are all endemic frog species with four listed in the IUCN red list: the nearly threatened Luzon fanged frog, Luzon forest ground frog and Guenther’s forest frog, and the vulnerable banded pygmy tree frog.
The MVNP also houses one endemic butterfly, seven endemic stick insects and nine endemic spiders in the registered insect and arachnid fauna.
These were the considerations submitted by the Philippine government to the Unesco to include the MVNP in the tentative list of Unesco World Heritage Site.
A separate profile prepared by the Biodiversity Management Bureau’s (BMB) Parks and Wildlife Division of the Department of Environment and Natural Resources (DENR) revealed that there are several rivers and creeks within the MVNP.
These are the Maagolgol, Bulawan, Bangliwan, Baranghaun, Bariw and Buang rivers; and the Miraya, Sabangan, Cabcab, Sidon, Uyangan, Pepe, Angtol, Ogob, Manadela, Mabalnos, Magsapit, Magasadit, Subangan, Tabiguian and Tancopan creeks.
Its biological features are also unique. The area is predominantly dominated by dwarf trees, grasses and few dipterocarp trees not fit for commercial purposes.
Wild pigs, civet cats and monitor lizards, likewise, thrive within the park.
Threats and danger
With the unpredictability of volcanic eruptions, such as the current activity of Mayon Volcano, Science Undersecretary Dr. Renato U. Solidum Jr. for disaster-risk reduction and climate change said there are strong possibilities that lava flowing out of the crater would eventually block and spill over the gullies.
The impact of a volcanic eruption to its surrounding environment, Solidum added, depends on the mineral deposit emitted by the volcano. Although deadly, most of the time, these minerals emitted by the volcano are beneficial to the environment. The ash spewed by Mayon that is currently covering Guinobatan town would block the gullies and spill over to farmlands.
“Fortunately, there are no farms along the path of the lava,” said Solidum, who is also the officer in charge of the Phivolcs.
Areas covered by thick ash, lava, volcanic rocks and other debris would be rendered useless for agriculture for years, he added.
The lava would kill forest vegetation—trees, shrubs and grass—and cover vast portions of some rivers and creeks, damaging the ecosystem.
The ashfall, which is common, during volcanic eruptions, often has little negative impact on the environment, except for the temporary air pollution.
In fact, Solidum said, later on the ash will be beneficial to the soil as the mineral deposit spread over vast land areas will replenish the soil cover with minerals and make it fertile in the long run.
Years after a volcanic eruption, the threat of lahar remains as heavy rains would eventually wash away downstream the debris accumulated on top of the hills, potentially “killing” rivers and adversely affecting other water bodies. However, again, Solidum said ecosystems affected by volcanic eruption will eventually recover as the soil becomes fertile.
“In general, a volcanic eruption has its benefits. Besides enhancing soil fertility, it also promotes tourism,” he said.
Unless covered by lava or lahar flow, trees in the forest would grow back, he added, agreeing to the observation that despite the frequency of Mayon’s eruption, its lush forest eventually bounces back and sustains life because of the fertility of the soil brought by the minerals sprinkled by the volcanic eruption.
Effect on biodiversity
A volcanic eruption often has an adverse environmental impact that threatens the biological diversity near the volcano, the country’s top biodiversity official said.
Director Theresa Mundita S. Lim of the DENR-BMB said as ashfall, lava or lahar affect forest and forest vegetation, animal wildlife tends to migrate or transfer to safer grounds.
“Volcanic eruption affects biodiversity as it affects the vegetation and the animal wildlife species around the area that are not mobile,” Lim said.
“What is important,” she added, “is to protect the remaining biodiversity-rich areas which can serve as shelter and sanctuary of natural pollinators and seed dispersers that will evacuate from the affected areas.”
According to Lim, even a massive volcanic eruption will not cause the extinction of plant or animal species for as long as the same species continue to exist in other areas.
Areas that are not affected by the volcanic eruption, she said, will be the source of seeds and seedlings of, hopefully, native species of plants and trees that will regenerate the forest and lure back animal wildlife that were lost from the eruption.
“On the positive side, the soil will be very fertile and will allow natural regeneration to take place more quickly,” she added.
In the case of affected areas in Albay, she said she expects the population or distribution of animal wildlife to drop, albeit temporarily.
Animal species that could not move quickly, she said like amphibians, flightless insects and arachnids, could easily detect danger and transfer to safe grounds long before a volcanic eruption occurs.
“In any case, if there are other areas in Albay or the Bicol region where the same plant species can still be found, then we still have sources for propagation and restoration. All we need are the birds and the bees and bats,” she said.
“What is important is that people are aware of these areas so we can exert more effort in protecting these identified alternative natural gene-pool sites,” she explained.