New Delhi: An Indian student is all set to begin her PhD course in Earth Sciences looking at climate change in the Indus Valley at the University of Cambridge, after being awarded a prestigious Gates Cambridge scholarship in recognition of both her academic achievements and social leadership.

Yama Dixit is one of 90 new scholars starting at the University later this month. The scholarship programme was established in 2000 by the Bill & Melinda Gates Foundation to enable outstanding graduate students from outside the United Kingdom to study at the University.

They are awarded on the basis of a person's intellectual ability, leadership capacity and desire to use their knowledge to contribute to society.

Yama did not start studying the environment until her second year of undergraduate studies at Delhi University (DU) after she revisited the site of her earliest childhood memories of taking part in the religious ablutions in the river Ganges at Haridwar.

When she revisited it she found, to her horror, that the ecosystem had been absolutely devastated. "In the place of green hills and shady trees were squalid houses and shops," she says. What began as a desire to return things to their "natural state" developed into an ambition when she visited Vaishno Devi, another sacred site in the mountains.

Here too, she witnessed destruction in the form of deforestation. She decided to switch to studying environmental sciences at Jawaharlal Nehru University (JNU).

At JNU she got a lot of encouragement from one of her lecturers, Professor V. Rajamani, who supervised her Masters project. She credits him as being a key reason for her winning a coveted Junior Research Fellowship (JRF) in Earth Sciences. This in turn led to her getting to the second round of interviews for the prestigious Shyam Prasad Mukherjee scholarship.

Another more personal influence on her academic career has been her parents. Her father put his career on hold while her mother completed a PhD in Sanskrit, despite strong social pressure for her to discontinue her studies.

At university, Yama, aged 24, became involved in several extra-curricular projects. At Hansraj College, Delhi University, she lived in Kamla Nagar where she and some friends started up some classes for street children who were forced to work against their wishes.

"We saw underprivileged kids on the road, making a living, while we were hanging out," she says. "We went to their parents and told them the importance of education and we collected funds from the college students and saved our pocket money so we could buy books and stationery for them."

Yama says she loves to teach, particularly people who do not get the opportunity to learn. At JNU, for instance, she has been teaching people working in her departmental canteen. "These people cannot even calculate their wages and thus they were always hoodwinked by their employers," she says.

In April, she and some friends formed a Society called "Think for All" to encourage people to do voluntary work to help marginalised members of society. Within JNU she has also been active in promoting public health and environmental issues.

As councillor of the School of Environmental Sciences, she arranged cleaning drives, no smoking campaigns and organised a week-long celebration for Earth Day involving local schoolchildren in painting and collage-making competitions on environment-related issues.

All of this, a broader outlook made her a perfect candidate for a Gates Cambridge scholarship, but she only found out about the programme by surfing the Internet.

Yama, who since her early childhood has studied Kathak dancing, was attracted to the scholarship because of the University of Cambridge's reputation and also because she saw it as a great opportunity to interact with students in various fields from all over the world.

Her PhD will focus on reconstructing a model for climate change in the Indus Valley. Using drill cores from a dried up lake in NW India, she will seek to reconstruct the local palaeoclimate history and rainfall patterns of the region occupied by the Harappan civilisation of 2500-1600 BC.

The sediment which is unearthed will be checked for elemental and isotopic composition and dated by radiocarbon. Any changes in the oxygen isotopes of shell material will be analysed to show monsoon intensity and the ratio of lake evaporation to rain.

Yama says her study will provide the first record of palaeoclimate data in NW India for the Holocene period.

She says: "Our society is increasingly interested in the consequences of future climate and environmental change, as well as the role humans have played in these changes. Human civilisations throughout history have affected the environment and perhaps influenced climate through deforestation, agriculture, urbanisation and industrialisation. My research on how ancient civilisations affected their environment and in turn how environmental and climate change may have influenced cultural revolution will help us to draft management plans to avoid the same catastrophic climax for our own civilisation as that which befell the Harappan civilisation."