OSLO, (Reuters) – Brazilian senator and former  environment minister Marina Silva won Norway’s $100,000 Sophie  Prize for her work to protect the Amazon rainforest, the prize  foundation announced yesterday.

The Sophie Prize is awarded annually for environmental  protection and sustainable development. It was set up in 1997 by  Norwegian author Jostein Gaarder and is named after the main  character of his book “Sophie’s World.”

Silva, who was environment minister in 2003-2008, clamped  down on illegal activity in the forest, the Sophie Foundation  said in its citation.

“During this period she reduced deforestation in the Amazon  to historically low levels — by 60 percent from 2004 to 2007,”  it said.

“Huge areas were conserved, more than 700 people were  arrested for illegal activities in the forest, over 1,500  companies were closed down and equipment, properties and illegal  timber were confiscated. These measures were effective.”

Brazil’s rainforest absorbs huge amounts of carbon dioxide  (CO2) — the main gas blamed by scientists for global warming —  and rainforest conservation is crucial to limit the greenhouse  effect and dramatic climate changes, the foundation said.

During Silva’s last three years in government, deforestation  was reduced to the second lowest level in 20 years, it said.

“She also balanced the concerns of indigenous peoples’  traditional farming societies,” it said.