Mangroves under threat

Mangroves under threat

Volume M/Number 9/September 1997 discover end-user requirements for timely information, The project will use SAR imagery from the Canadian Radarsat sa...

221KB Sizes 2 Downloads 60 Views

Volume M/Number 9/September 1997 discover end-user requirements for timely information, The project will use SAR imagery from the Canadian Radarsat satellite and process the data with the Oil Spill Detection Workstation (OSDWS) located at the receiving station in West Freugh, Scotland in order to execute a real-time service. This will offer a realistic user-driven approach to the demonstration of an oil spill information service, coupling data providers to the

old and dirty, can be used to make bitumen for roads. Shell Bermuda have also offered assistance if needed.

real customers.

No environmental assessment appears to have been made of Karachi Harbour, Pakistan in spite of the apparently high levels of pollution present according to a recent report from Environmental News Service

ALAIN FEBVRE

Radioactive Contamination at

La Hague Access to the area around the French reprocessing plant discharge-pipe at La Hague is to be restricted following the results of an independent analysis on samples from the area conducted by the Department of Labour, Health and Social Services of the Federal State of Hamburg. The analysis confirmed that the effluent and sediment samples are radioactive waste. According to the analysis of the German Institute, the effluent contains up to 160 becquerel of tritium per litre. The plutonium levels also classify the sediment as 'waste containing nuclear fuel' and German law prohibits such discharge into the sea. La Hague's permission to discharge effluent into the sea is being re-assessed, with French authorities making a decision by September of this year. Greenpeace have welcomed the restrictions but have also asked that a full public environmental impact assessment of all the operations of La Hague should be carried out.

The

Black

narbour

Waters

Of Karachi

(ENS). An

unnamed official leaked the information to ENS indicating his considerable concern over the state of the harbour. According to the official, there is frequent spillage of oil from ships in the harbour when it is pumped through pipelines in the oil installation into the storage tanks and again when the stored oil is pumped into the road based oil tankers for transport into the country. There is a constant strong smell of oil from the harbour water. As yet there appears to be no data available on pollutants in the water or sediment in the 120 km 2 harbour area. Pollution other than oil is believed to be present as well. There are dredgers which remove the sediment but according to the official it is redumped so close to the harbour area that it soon returns. He did not believe that the dredgers had been chosen for reasons of environmental concern and hence were not completing a satisfactory removal of sediment. Karachi can handle ships of 75 000 dead weight t and yet has no boom pipes to deal with oil spillage. Most ports have had these booms in operation since the early 1980s but the boom purchased for Karachi last year still had not arrived by July this year.

Bermudan Caves used as Oil Dump by Royal Navy

Mangroves Under Threat

An estimated one million gallons of waste oil found in caves near the old HMS Malabar in Bermuda is to be cleaned up. The oil was discovered in 1995, when an environ-mental consultant did a study for the Navy base. The dumped oil, some of which may be as old as the early 1900s, has formed a thick black oil sludge on the cave floors and extends quite some distance. There appears however to be no leakage of oil into the surrounding sea from the caves. The oil has accumulated after being dumped in the area from Royal Navy ships for decades and the U K Ministry of Defence is to pay for the clean up. The work was due to start in August and is expected to take three years to complete on account of the massive quantity o f oil involved, However, once underway it should not be labour intensive, just time-consuming. The free oil will be cleared first, drawn up by pumps as a water/oil mix and transported to the US for disposal where, if it is not too

One of the world's largest mangrove forests is being threatened by the lowering of flow and increasing pollution of the Indus River according to a recent report by Ahmar Mustikhan of ENS. Apparently, discharge of freshwater from the Indus River into the delta stood at some 150 million acre feet some decades back, but this has been reduced to only 10 million acre feet on the basis of the Indus Water Accord among the four provinces of Punjab, Sindh, Balochistan and Frontier. The reduced water flow has resulted in increased salinity which appears to be killing mangrove species that are unable to tolerate high levels of salt. Four species have already been wiped out and a number of other species are believed to be severely threatened. Fortunately the most salt tolerant species, Avicennia marina is also the most abundant making up 95% of the forest. However, increasing salinity is only one of the 683

Marine Pollution Bulletin

threats to the area which is subject to the dumping of millions of gallons of untreated sewage in addition to an annual beaching of some 20 000 t of oil from shipping and coastal oil installations, According to Mustikhan, it is estimated that the mangrove forests have reduced from coveting an area of 1600 km 2 (1000 miles2) in the 1960s to just over 960 km 2 (600 miles/ ) today. Pressure also comes from domestic needs as local people use the foliage as feed for camels and cattle. This has been estimated to account for some 18 000 t annually,

Minamata Clear

"g,ven the All

A name synonymous with environmental disaster, Minamata Bay in Japan, has been declared free of mercury 40 years after its waters were the cause of death and birth defects. The Governor of Kumamoto prefecture in south-west Japan has declared the bay to be safe for fishing. Chemical companies had dumped mercury in the bay for decades but it was not until the 1950s that the problem began to emerge. The mercury had been accumulated by shellfish and fish in large doses in their tissues and these doses were then passed on to anyone eating them proving highly poisonous to the victim. Hundreds of people have died over the years following, others have suffered spasms and blurred vision while babies have been born with disfigured limbs. The greatest polluters were the Chisso Corp. who dumped tons of mercury compounds into the sea around Minamata city, 1056 km (660 miles)southwest of Tokyo, from 1932 until the mid-1950s. It took some years to determine the cause of the health hazards, and even when established, it was not until 1968 that the government prevented any further dumping. It took until 1995 before compensation for victims was set aside. 30 billion yen ($225 million) was used in state subsidies and bonds to compensate the victims, Since the intervention of the government in 1 9 7 4 Minamata Bay has been sealed off with nets to prevent organisms contaminated with mercury from leaving and affecting other areas. The removal of the 380 ha of netting should be completed by the end of September. For three years the surveys have shown that the levels of mercury have fallen to less than accepted government standards. It is still unsure whether people will feel secure eating fish from the bay in spite of the reassurances as it has been contaminated for so long that lingering fears are bound to persist. However, fish from the bay will be distributed in fish markets very soon. PHILIPPA AMBROSE 684

H e l p for S h a r k B a y The Australia government is to provide AU$ 490 000 to fund crucial work to conserve threatened native animals in Western Australia's Shark Bay World Heritage site. This is almost treble the funding made available the previous year. The funding will contribute to reintroducing and monitoring populations of four endangered species and to improving visitor information services and facilities at Shark Bay which is located 400 km north of Perth. According to Federal Environment Minister, Robert Hill, one of the main reasons Shark Bay is included in the World Heritage List is that it is home to five of Australia's endangered mammals that live on the Peron Peninsula. It also supports the loggerhead turtle and the

dugong. The Cononwealth is providingfundingto help protect and increase the populations of three of the terrestrial species and funding is being provided to develop management strategies to protect the turtles and dugong in the region. Several studies into the marine environment of Shark Bay, centering on Monkey Mia, are also being funded to assess possible adverse impacts and any necessary actions to ensure these areas are protected.

"11~

_ O i l _*

__

t , rnung perauons Threaten Beaufort S e a W h a l e s The National Oceanic and Atmospheric Administration (NOAA) is proposing to authorize gas and oil exploration operations in federal and state waters in Alaska's Beaufort Sea which will result in the harassment of various seal species and possibly bowhead and beluga whales. Under the Marine Mammal Protection Act, ARCO Alaska Inc. applied for authorization to disturb small numbers of the mammals during five and a half months of drilling operations in Camden Bay, Alaska. NOAA have already determined that the proposed activities would cause harassment of seals and whales, but believe this would result, at worst, in temporary behaviour modification, with negligible impact on species stocks. Authorization would require a trained mammal observer to be on board transport vessels to search for and record the behaviour of marine mammals during the equipment set-up phase. In addition, a series of mitigation measures would be imposed, including the shutdown of drilling operations during bowhead whale migration and prohibition of drilling in areas where ringed seal lairs may be present. Public opinion has been sought on this issue by NOAA's National Marine Fisheries Service. SHIRLEY HENDERSON