scientist attached to the Bermuda Biological Station an invitation to the Earth Summit, held last month in Brazil.

Miss Joanna Ellison who has just returned from Rio de Janeiro, had her trip funded by UNESCO, the scientific arm of the United Nations, as a member of their official task force on climate change.

At the summit, the UNESCO-supported International Society for Mangrove Ecosystems was active in the appending of a Charter for Mangroves to the overall Earth Charter, approved by all countries that have mangroves and setting out basic principles for their conservation and usage. At this meeting, Miss Ellison reported on Bermuda and Cayman on the current status of mangrove conservation in the American hemisphere.

The UNESCO Task Team on Climate Change Effects on Mangroves met in Rio to select sites and methodology for long-term study.

"It was quite an honour to be chosen as the other delegates were all professors or heads of departments.'' Miss Ellison, who will be granted a doctorate in December for her work on the mangrove swamps at Hungry Bay, was the only scientist whose papers were singled out for specific mention in the Conference's background analysis on the worldwide mangrove situation.

Found to be particularly useful to the meeting was her 10,000-word study, Impacts of Climatic Change on Ecosystems and Species, which includes her observations on Bermuda. This is to be published soon by Cambridge University Press, in a volume entitled Impacts on Climate Change on Ecosystems and Species, with expert assessments from other world ecosystems.

Miss Ellison's invitation to attend the summit arose out of her visit to Bangkok last November, when UNESCO asked her to give a presentation on Bermuda's mangroves and their susceptibility to sea level rises. As a result of her findings, it was decided that a low-island site, where there are no rivers, should be included in the massive, UN-funded survey of mangrove ecosystems that is to be undertaken as a result of the summit.

"Although Bermuda's mangroves are unique in many ways, it is a relatively small system. That is one of the reasons why Bermuda was not chosen by UNESCO as a site for long-term research. Cayman and Tonga, both of which are my research sites, were eventually selected, so I was very happy about that,'' she says.

It should be noted, she explains, that in other areas of the world, the effect of climate and sea level changes on mangrove forests are of paramount importance. In the tropics they form a natural storm barrier between the ocean and the mainland and provide a natural resource base for silviculture and a large range of traditional economic products. In the Caribbean, they are also a valuable breeding ground for fish.

The American Environmental Protection Agency recognises that mangroves are likely to be the most sensitive ecosystems of all to climate change and have just committed $1 million to research on this.

"There wasn't much science actually going on at the summit, as most of the groundwork had been done beforehand -- the main emphasis was the political angle, trying to get everyone to agree on steps that should be taken. But it was a fascinating experience,'' she says, "because so many countries took part.'' Exact numbers were difficult to obtain, as many fringe groups gathered unofficially in Rio to lobby their particular interests, but it was estimated that between 25,000 and 30,000 people and 114 Heads of State converged on the spot that has become as famous for its crime rate as for its glamorous resort image.

"Everyone in Rio was very anti-Bush. All these countries had gathered there, hoping that something would be done, but he was looking to the needs of the US economic machine and safeguarding that at any cost, instead of trying to look after the world's climate and ecosystems.'' Miss Ellison says that the generally accepted view at the summit was that these changes have already started and can be seen in the increase of huge, freak storms such as the one that hit the UK a few years ago, sudden frosts in Florida, unusually long droughts and torrential rains. "But no scientist can be 100 percent certain of what is going to happen, so the politicians grasp on this and use it as an excuse to do nothing at all. The US refusal to sign the original wording of the emissions control declaration was a shame, as in the '70s, they were the true leaders of the earth summit held in Stockholm and the most active in bringing about changes in developing countries. Now, 20 years later, the only country that was being obstructive was the US.'' Miss Ellison stayed in a hotel just outside the centre of Rio. "The security arrangements were incredible. We were warned not to wear any jewellry and to leave bags behind. All the sidewalks were closed off in front of the hotels where the VIP's were staying. We had to travel by bus -- at $20 a trip -- to and from the conference centre, which looked like the interior of the Starship Enterprise. There were army tanks and armed soldiers everywhere. The local Brazilian people were astonished by this as the army hasn't been seen out in the open for years. Ever since they had a coup in the '60s, the army has been kept undercover, in secret camps.'' She says that the stringent security operations did limit the opportunity to attend meetings or to even move around Rio with ease, "although I managed to attend a ceremony on the opening night of the summit, when women only were gathered on the beach. We all carried candles and were there to welcome the arrival of Gaea, the earth goddess, into the summit.'' The more colourful events, she says, were those staged by organisations like Greenpeace and the World Wildlife Fund -- who attracted attention by flying a giant balloon with their panda logo on it, over the sea at Rio. They were kept in touch with what was going on each day by the superb press coverage. "They produced a special paper, Earth Summit Times, which was mainly put together by the New York Times,'' she says.

Miss Ellison feels that one of the weaknesses of the summit was its failure to address the problems of developing nations. "Countries like Malaysia, for instance, are getting very tired of being told what they can or can't do with their forests. What we all sometimes forget is that the US and Bermuda chopped their forests down long ago, so these undeveloped countries feel it's a bit of a cheek to be told now that they can't do the same thing.'' SUMMIT MEETING -- Miss Joanna Ellison who was invited by UNESCO to attend last month's Earth Summit.

THE OTHER SIDE OF THE SUMMIT -- Armed troops patrol one of Rio de Janeiro's worst slums while 114 Heads of State gather in the beach-side resort for the Earth Summit.