By Alex Kirby BBC News Online environment correspondent

One of the world's largest financial services organisations, HSBC, is giving almost $50 million (�35m) to three environment charities.

It is funding the global environment campaign WWF, Botanic Gardens Conservation International (BGCI), and Earthwatch.

The five-year partnership, Investing in Nature, is concentrating on water supplies and endangered plants.

It will also involve two thousand of the bank's staff working in the field on five continents.

HSBC says 1.2 billion people worldwide lack access to safe drinking water, nearly 34,000 plant species are endangered, and 88% of the Earth's species are thought to remain unidentified.

The bank's chairman, Sir John Bond, said: "Companies as well as individuals have a responsibility for the stewardship of this planet, which we hold in trust for the future.

"If we don't act now, by 2025 over 60% of the world's population could face a water shortage. We are also facing a global extinction crisis with thousands of species and habitats under threat."

A year ago HSBC, the UK's largest bank, announced a 28% rise in pre-tax profit to �7.1bn ($10.3bn) for 2000.

WWF will use its share of the grant to restore two million hectares (4,942,000 acres) of river basin habitats along the Amazon in Brazil, the Yangtze in China and the Rio Grande in the US.

'Noah's Ark for plants'

It says this will restore the rivers' natural flow, protect fish and other species, and secure fresh drinking water for millions.

Botanical gardens like Kew will gain

In the UK WWF will work to protect and restore freshwater habitats in line with new European Union legislation.

BGCI will use the money to fund "a living gene bank" in botanic gardens around the world to protect 20,000 endangered plants.

It says it will also "revitalise" conservation in 16 major gardens in Argentina, Brazil, India, Indonesia and the Middle East.

About 2,000 HSBC staff will work with Earthwatch scientists on conservation projects, and on their return home they will be given grants for local conservation schemes.

The Earthwatch share of the money will also help to train 200 scientists in developing countries.

Irene Dorner, head of human resources at HSBC, told BBC News Online: "This is part of our belief that we have to put something back into the societies where we operate.

"The bank will get something out of it, too. Our staff will be contributing the equivalent of a century of labour on those Earthwatch projects.

"They'll come back with a different pair of eyes. And we'll gain their experience."