Vietnam: Don't let sand miners destroy our heritage

Tran Le Tra Viet Nam News 6 Aug 15;

My generation grew up realising that Viet Nam, according to the geography textbooks, is ceaselessly and naturally expanding outwards to the sea, particularly in the south.

Some even estimate that if the cape of Ca Mau keeps on growing steadily southward at the pace of 500 metres a year, then within less than 800 years the southern-most point of the country will be connected with the peninsula of Malaysia.

However, in the past few decades, Vietnamese geography textbooks remain unchanged. The shape of Ca Mau and the pattern of its replenishment by sediment, however, have changed dramatically.

In the Mekong River Delta, one can still observe just how much sediment is being carried downstream, to be deposited around the mouth of the great river.

This contrasts with other coastal areas where Viet Nam is e losing land due to coastal erosion at an unprecedented pace, due to some extent to climate change.

Up to 256 cases of serious erosion covering a total length of 450km along the coast line have been recorded. Thousands of hectares of land collapses into the sea each year. In Ca Mau province alone, coastal erosion swallows up to 927ha of land a year. Consequently, the "nose" of Ca Mau is now no longer the furthest southern point of the country and Mekong Delta provinces are losing a medium-size commune each year.

At the Forum on Natural Conservation and Culture for Sustainable Development of Mekong Delta, two core reasons for erosion were identified. One is the irresponsible constructions of dams and reservoirs for irrigation and hydropower and the other is over exploitation of sand and gravel in river bed of the Mekong. These two factors will soon be aggravated by the increasing agressivity of the wave pattern, which will be modified by climate change, and a rise in sea level.

The Mekong River Commission research shows that the suspended sediment load in the river declined from 160 million tonnes in 1992 to 75 million tonnes in 2014 due mainly to the construction of hydropower dams and reservoirs on the mainstream and tributaries of Mekong River.

Sand and gravel mining is taking place in all four Lower Mekong countries, but the largest extractions are happening in Cambodia and Viet Nam. In the Vietnamese part of the delta alone, more than 150 sand mines covering a total area of 8,041ha of water surface in 13 Mekong Delta provinces have been licensed by the provincial governments.

While the total reserve of sand in Mekong River is estimated at 816 million cubic metres, the total amount of sand mined from the lower Mekong main stem (in Laos, Thailand, Cambodia and Viet Nam) has been estimated by WWF at 35 million cubic metres per year.

A more recent sand mining estimate in the Viet Nam part of the delta by the Southern Institute for Water Resources Research is as high as 28 million cubic metres.

We are well aware that the loss of land in the Mekong Delta is no longer a myth. It is happening, and human actions,not nature, are responsible for it. "Management of sedimentation in Mekong Delta is now an issue of great concern," said Dao Anh Dung, vice-chairman of Can Tho People's Committee.

"The management of resources in a river that bring nutrition to 13 provinces in Mekong Delta requires close and effective co-operation at all levels, including international." said Van Ngoc Thinh, Country Director of the World Wild Fund for Nature (WWF) in Viet Nam.

We are very close to the point of an irreversible process. And without appropriate and strong intervention, then within several decades all the land that has been created by nature for thousands of years will be gone.

The culture of the region, which is closely related to agriculture and fishery, and strongly dependent on the resources provided by Mekong River, would be affected. Our pride would suffer, geography textbooks would have to be rewritten - and our generation would have to answer why it had failed to protect one of our most sacred heritages.

To avoid this, it is of utmost importance that the sand mining industry in Mekong Delta as the whole is reviewed and replanned on the bases of careful assessments and scientific evidence. This may be started with the development of an effective coordination mechanism among provinces in the region.

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Malaysia: Horseshoe crab population in Sabah down sharply

Daily Express 6 Aug 15;

Kota Kinabalu: The horseshoe crab population in Sabah is down sharply due to the loss of mangrove habitats.

It could be due unequal sex ratio – males outnumber the females, thus disrupting mating behaviour.

Field researcher Rolando Robert from Universiti Malaysia Sabah's Borneo Marine Research Institute links the imbalance ratio to human- related activities. He says decades of mangrove clearing and extensive beach reclamation in Kota Kinabalu have brought about these losses.

The Carcinoscorpius rotundicauda species is the focus of his research though Malaysia has two other horseshoe crab species ( out of four in the world), the Tachypleus gigas and Tachypleus tridentatus. He says previous assessments failed to provide an estimate of the population of the horseshoe crabs.

"We have tried locating their foraging and spawning habitats but with no luck. We have also tried the capture-recapture method but found it very difficult to re- capture them. They are elusive and information on their population dynamics is lacking at the moment," Robert says in an e- mail interview.

He is certain of one thing though: their occurrence at two study sites have declined dramatically, as supported by interviews conducted with local residents.

The first study site is Menggatal River where clams and other shellfish are harvested by local communities. The second site, the Kota Kinabalu Wetlands, is a research, education, and conservation centre for mangroves and fisheries is not allowed there.

"Both are breeding sites for horseshoe crabs. Fishermen and wetland authorities informed us that there are mating individuals and juveniles there, indicating that spawning activities have taken place," explains Robert.

He says monitoring work was conducted over four months – two nights during the full moon and new moon of each month, as that is the time when the horseshoe crabs venture into mangrove areas to spawn.

From the sampling, Robert and his research colleague Muhammad Ali Syed Hussein found the imbalance sex ratio. At Kota Kinabalu Wetlands, males outnumber the females by 2.58 to one, while at Menggatal River, the ratio is 5.5 males to one female.

The low number of females is a result of them being trapped in fishing nets since they have larger body sizes than the males.

Tests were also conducted in a controlled environment to determine mating behaviour: between one and four males were put into three separate tanks, with one female. Within a 30- day period, it was observed that mating occur most successfully in the tank which contained an equal number of males and females.

With fewer females, there is less chance of mating, and subsequently loss of new generation.

"The decline or disappearance of horseshoe crabs is almost always linked to habitat loss. In the natural environment, they lack predators and are generalists in terms of feeding preference, relying mostly on shelled animals, polychaete worms, and even detritus for sustenance. Hypothetically, if you take human intervention out of the equation, they will most certainly flourish," says Robert.

Muhammad Ali says what compounds the problem is renewed interest in horseshoe crabs as a delicacy. "While they have always been collected for their eggs, the crabs are now collected commercially ( especially in Peninsular Malaysia) for restaurants and for export to Thailand. Horseshoe crabs take a long time to reach maturity. The loss of breeding adults is highly detrimental to the population."

Robert says the spawning population of horseshoe crabs remains unknown as there are no published records in Sabah so far.

The males can only be identified when they reach sexual maturity ( roughly 10 years). The sexual organs in females develop much earlier but identifying it will require powerful microscopes. "This explains the difficulty in determining the gender ratios of juveniles," says Robert.

He says the presence or absence of horseshoe crabs indicates the health of the habitat, be it the beach, estuary or mangroves.

Horseshoe crabs are valued for a compound in their blood that can be used to detect the presence of bacterial contaminants in drugs and medical apparatus. Two years ago, the Sabah Government provided funds to a university to conduct a population assessment of horseshoe crabs and assess the feasibility of setting up an endotoxin detection kit manufacturing industry.

Muhammad Ali adds that horseshoe crab eggs are an important form of nourishment for shorebirds which arrive in Sabah's coastlines after long- distance migration.

At present, horseshoe crabs are not protected locally or regionally. A global network of horseshoe crab specialists is collecting more data to determine the status of the species in the Indo- Pacific region.

"I believe the best way to conserve horseshoe crabs in Sabah is by protecting of their spawning and feeding habitats. It is important that they are able to reproduce continuously because affected populations may take decades to rebound to their undisturbed state. Captive breeding will not be effective as wild- caught horseshoe crabs do not fare well in a man- made setting," he says.

Robert says despite their menacing appearance, horseshoe crabs are harmless towards humans, and have a lineage that goes back over 400 million years ago, appearing before dinosaurs did, and outliving them.

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El Nino has emerged and expected to strengthen: Australian weather bureau

COLIN PACKHAM Reuters 4 Aug 15;

An El Nino is now well established and continues to strengthen, the Australian Bureau of Meteorology (BOM) said, with models indicating that sea-surface temperature anomalies in the central Pacific Ocean are set to climb to the highest in 19 years.

The El Nino, marked by a warming of sea-surface temperatures in the Pacific, can lead to scorching weather across Asia and east Africa but heavy rains and floods in South America.

"This past week the central tropical Pacific is 1.6 degree Celsius above normal, and slowly warming still - and forecast by models to continue warming," Andrew Watkins, supervisor, Climate Prediction Services at the BOM, said on Tuesday.

"Remember, peak values typically occur late in the year so we have a three to seven months to go before we may peak in the current event. The 1987 (event) peaked in August – all other events peaked between November and February," said Watkins.

Further warming is likely, according to models monitored by the BOM, with an average peak reading of +2.7 degree Celsius above normal by December expected.

Should that forecast be realized, it would be the biggest anomaly since 1997, surpassing the top recordings associated with the El Ninos of 2002 and 2009, data from the BOM shows.

The 1997 El Nino was the last "very strong" event recorded, though the BOM concluded the overall impact to be weak, with major crops withstanding much of the dry weather associated with the system.

The outlook reinforces the BOM's view that the developing El Nino could be a "significant event", threatening Australian production of staple crops such as wheat and sugar, and providing further pressure on the country's cattle farmers.

With the El Nino event still developing, the BOM said the weather event will likely persist until early 2016.

(Reporting by Colin Packham; Editing by Himani Sarkar)

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