from the Sahara desert and dumps it on Bermuda.

The process has been studied for decades -- with key facts uncovered by Bermuda Biological Station experts.

But now the full picture has begun to emerge, thanks to a series of breakthroughs.

Scientists believe dust from droughts in Africa can blow across the Atlantic to South America, the Caribbean and Bermuda.

And they think particles may boost the growth of tiny plants in the Atlantic and even feed the rainforests of South America.

Some of the latest research is being done by a team backed by the US space agency NASA in Namibia, southern Africa.

It was being examined yesterday by Biological Station director Dr. Tony Knap who himself edited a book on the subject two years ago.

He said that although it had long been known that African dust was carried by winds and landed on Bermuda, he was interested in work done by US scientists on the possibility that iron in the dust fertilises the ocean.

Such an idea was first promoted in Bermuda in 1958 -- by Biological Station scientists Mr. David Menzel and Mr. John Ryther.

"They noticed that there was a fertilising effect from rainwater and postulated that iron could play a very important role,'' he said.

It had long been proposed that a lot of the soil in Bermuda had its origin in the Sahara desert, he added. Dust reached the Caribbean after travelling across the Atlantic and could then travel north.

"We're not in the mainstream of that dust, but a lot of it is respon sible for the build-up of soils on the Island,'' he said.

Dr. Knap said work on dust fertilisation might eventually help scientists work out how to offset the "greenhouse effect'', believed to be caused by increasing carbon dioxide in the atmosphere.

Fertilising tiny plants in the sea could boost the amount of carbon dioxide they removed from the air.

Dr. Michael Garstang of Virginia University, one of the scientists in the NASA-sponsored project, said: "This African dust feeding the Atlantic and the Americas shows how very large and distant ecosystems depend on each other.

"The message is that our planet consists of many interconnected and interdependent systems which we barely understand. But if we want to know how man is affecting the planet, we first have to know how these systems work.''