Early tipping points | Inquirer Opinion

Early tipping points

“The sight of three-foot tall hyacinths, clogging Rio Grande de Mindanao, was numbing,” Jonathan Domingo of the Mindanao Cross recalls. “One saw ordinary people and 6th Infantry Battalion soldiers working alongside Moro Islamic Liberation Front regulars so water could  flow to Illana Bay and the floods would recede.”

“No talk of war,” this Oblate priest noted. “But a common threat united us. We’ll need that unity if more rains uproot hectares of hyacinths from Liguasan Marsh.”


Welcome to the Harassed Club.

The Philippines joined other places plagued by “water lilies” or eichhornia crassipes: Lake Victoria in East Africa, Kerala’s backwaters in India, Lousiana swamps and Papua New Guinea.


Five cities and 48 municipalities in Mindanao were lashed by torrential rain, the National Disaster Risk Reduction and Management Council reported. That dislodged hyacinths. Deforestation, siltation and emergency release of water by power plants compounded the problem. Notre Dame schools and cockpits in Cotabato morphed into evacuation centers.

President Aquino declared “war versus water hyacinths.” Beyond cleaning of waterways, researchers would probe use of water lilies as energy source.

Fine. But what is involved? “A water hyacinth infestation is seldom totally eradicated,” a UN study points out. “Instead, it is a situation that must be continually managed.”

These water lilies are a pernicious invasive species from South America. Their size can double in two weeks. They block water flow and prevent sunlight from reaching native aquatic plants.

Massed hyacinths deny oxygen to water. This results in fishkills, like those still ravaging Taal Lake and Laguna de Bay today. Mosquitoes breed in them too. So does a parasitic flatworm which causes schistosomiasis or snail fever.

Chemical removal is costly and ineffective. “Try explosives,” a worried Local Government Secretary Jesse Robredo suggested. In Mindanao, backhoes, bolos and brawn were pressed into service.

The United States and 20 other countries opted for biological control. The US Agriculture Department, in the 1970s, released three species of weevil that chomp on water hyacinths. It has had limited success. Control of nutrients that hyacinths feed on may yet be the ace among preventive measures.


“Better read the weather forecast before praying for rain,” Mark Twain once joked. But rains in the first week of June over some areas of Mindanao were two and a half times than usual. “This is abnormal,” Pagasa’s Edna Juanillo told Agence France-Presse. In Cebu, rainfall in January was triple the usual downpour.

Do these rainbursts and water hyacinth “implosion” indicate that something more worrisome is happening? Yes, say the US National Science Foundation and the National Oceanic and Atmospheric Administration in their new study, “Shifting Band of Rain.”

Earth’s most prominent rain band, near the equator, has been moving north at an average rate of 1.4 kilometers a year for three centuries, writes University of Washington’s Julian Sachs and Conor Myrgvold. Today’s global warming spurred that process.

The band supplies fresh water to almost a billion people. It affects climate elsewhere, the report adds. “At current warming rates, the band could shift north by five degrees by 2100. That  would dry farmland for millions of people in Ecuador, Colombia and others near the equator.”

The sea level has risen rapidly, Vital Signs points out. More than half (55 percent) of sea level rise “results from the melting of glaciers and the Greenland and Antarctic ice sheets.”

Seventy percent of Filipinos cluster in coastal areas.

Fishermen are reeling from the impact.

Warming of sea water is associated with El Niño episodes. These caused “coral bleaching on massive scales never seen before,” notes Ocean Heritage.

El Nido reef, for instance, once had 60-70 percent coral cover. El Niño, a decade ago, stripped that down to 5-10 percent. It has not recovered to date.

Sea surface temperature in Bolinao, Pangasinan, ranged between 34.1 °C and 34.9 °C. That grilled giant clams.

“In the Philippines, rice yields drop by 10 percent for every one degree centigrade increase in night-time temperature,’’ noted Nature Geoscience last August.

“We can’t just move crops north or south,’’ cautions Dr. Geoff Hawtin of the International Centre for Tropical Agriculture. “Flowering is triggered by day length…Tipping points could come quite quickly.”

Far quicker than most thought, says the 2011 report on “State of the Oceans.”

“We’re entering a phase of extinction of marine species unprecedented in human history,” Alex Rogers, Oxford University’s professor of conservation biology writes. “We’re seeing changes we didn’t expect to see for hundreds of years.”

These “accelerated” changes include melting of northern glaciers, sea level rise, and release of methane trapped in the sea bed. Some species are already fished way beyond their limits.

“We must bring down CO2 emissions to zero within 20 years,” adds Ove Hoegh-Guldberg of the University of Queensland. “If we don’t, we’re going to see steady acidification of the seas. Heat is wiping out things like kelp forests and coral reefs. And we’ll see a very different ocean.”

“The rate of change is vastly exceeding what we were expecting even a couple of years ago,” he adds.

It is urgent to stop exploitative fishing now. Dumping of pollutants into oceans must stop. That’d include plastics, agricultural fertilizers,  human waste – and water hyacinths?

(Email: [email protected] )

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TAGS: environment, Fishing, Global Warming, Marine Resources, Water hyacinths, Water lilies
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