Philippines: Nipa habitat on the decline

Eufemio T. Rasco Jr. Malaya 12 Aug 11;

MANGROVES, where nipas grow abundantly, are on the decline in the Philippines.

As in other Southeast Asian countries, mangroves have been converted into what was believed to be more profitable ventures.

In the 1950s, vast tracts of mangroves were awarded by the government to concessionaires and logged over for firewood and tan barks. Mangrove firewood was the preferred fuel for coastal villages and most bakeries because of its high heating value. Mangrove firewood was exported to Japan as a source of rayon.

Starting in the 1960s, the government encouraged prawn and bangus farming in mangroves. These resulted in the reduction of mangroves from 500,000 hectares in the beginning of the 20th century to only 117,000 hectares in 1995.

It is estimated that half of the mangrove forests, or about 141,000 hectares, was lost to fishpond construction.

In effect, what were once common property of multiple use and benefit to a large number of people was narrowly channeled to the benefit of a select few.

Shrimp and fishponds are now being abandoned voluntarily. But the economic folly of conversion is not the reason why. It is the unsustainability of shrimp and fish farming in former mangroves.

Pond soil has gradually becomes acid sulfate, which indirectly causes toxicity to shrimps.

In the Philippines, Taiwan and Thailand, shrimp farming collapsed because of diseases that reduced profitability.

Today, more money can be earned from undeveloped mangrove forests.

As a crop, nipa is unaffected by typhoon or unfavorable weather. It does not need to be replanted. And it continues to produce sap for 50 years or more without replanting.

One fruiting head could have as many as 90 fruits. The fruit is used as food in Indonesia, Malaysia, Vietnam, Thailand, India and Bangladesh – but not in the Philippines where the fruits are simply left to rot or made into handicrafts.

There is a thriving cottage industry based on the nipa leaves used in bahay kubo or thatched houses. Thousands of people, particularly women and children, depend on nipa shingle production as their main source of livelihood.

The leaflets are used for making raincoats, hats, baskets, mats, bags and wrappers for sticky rice delicacies. The midribs are used for coarse brooms and the petioles for fuel.

The nipa shingle industry is for the poorest of the poor. In Vinzons, Camarines Norte, a conservative estimate shows people producing 1.2 million leaflets per hectare per year. Based on P150 per 100 shingles, this is worth P36,000.

One hectare of nipa could provide 240 man-days of employment for weaving (assuming one weaver can make 100 shingles a day); and 50 man-days for leaf gathering (assuming one gatherer can get 25,000 leaflets a day).

The young seeds are edible and the nipa sap is a source of vinegar, sugar and alcohol. The fermented juice called tuba is extensively used as a beverage, the earliest record of which was made by Pigafetta during the 1521 voyage of Magellan.

The World Agroforestry Center estimates the annual sap yield per hectare is 126,000 liters in the Philippines. For alcohol production, one person can tap 250 nipa plants a day and turn in 180 liters of sap, enough for one load using the native distilling apparatus which produces 30 liters of a 70-proof, colorless alcoholic brew.

It is a raw material for sugar as the sucrose content of nipa (up to 17 percent) is higher than that in sugarcane (12 percent). When the sap is collected within 12 hours, only a slight fermentation takes place. Boiled in open pans, the saps turns into a brown mass, like the panocha or solidified sugar made from cane.

Except for crushers which are unnecessary, the same facilities required for making sugar from sugarcane juice are needed for nipa.

After coconut, nipa is the second most popular raw material for vinegar; the are buri and kaong.

When distilled to 100 percent alcohol, roughly 10 liters of ethanol is produced. Which makes nipa an alternative fuel source.

The Biofuels Act mandates an increasing proportion of ethanol in fuel blends – 10 percent by 2011.

And yet, aside from sugarcane, which is the main source, cassava and sweet sorghum are being explored as sources of alcohol. Somehow, nipa – the world’s cheapest source – had been forgotten.

This doesn’t seem to make sense. The alcohol yield of Philippine nipa is about 10,000 liters per hectare per year – and could be doubled with improved management.

Unlike sugar, cassava and sweet sorghum, nipa does not compete with food crops for land and water because it grows where most crops cannot grow. It requires very little maintenance because once established, it will last for at least 50 years – if not forever.

The main constraint is labor intensity which accounts for almost the entire cost of the sap. But in a country where rural unemployment is very high, labor-intensive sap gathering is an advantage; nipa is abundant in the country’s poorest areas: Bicol, Eastern Visayas and Northeast Mindanao.

Even though the list is long, new uses for nipa are still being discovered: for treating wastewater contaminated by heavy metals; as inhibition of metal corrosion; and as a possible source of pulping material.

Not only are scientists busy identifying the chemical components of nipa, they are studying the fungi, bacteria and other organisms associated with the plant.

They are building knowledge on the relationships between plant and organisms to give further clues on the survival skill of nipa as well as find application in food processing, industries, agriculture and the environment.

All these economic uses pale in comparison with the environmental roles of nipa mangroves which benefit everyone. Among these are its role as a breeding ground for fish and invertebrates and in maintaining the stability of the riverbanks and the removal of heavy metals from water.

Without mangroves, there will be less fish and more floods, as drainage is hampered by the collapse of riverbanks.

The environmental role of nipa is thus priceless.

(Dr. Eufemio T. Rasco heads the Philippine Rice Research Institute. The plant breeder is a member of the National Academy of Science and Technology.)