Answer by taking a quote from the following article:

Wangari Muta Maathai (  ; 1 April 1940 - 25 September 2011) was an internationally renowned Kenyan environmental political activist and Nobel laureate. She was educated in the United States at Mount St. Scholastica (Benedictine College) and the University of Pittsburgh, as well as the University of Nairobi in Kenya. In 1977, Maathai founded the Green Belt Movement, an environmental non-governmental organization focused on the planting of trees, environmental conservation, and women's rights. In 1984, she was awarded the Right Livelihood Award, and in 2004, she became the first African woman to receive the Nobel Peace Prize for "her contribution to sustainable development, democracy and peace."

On 28 March 2005, Maathai was elected the first president of the African Union's Economic, Social and Cultural Council and was appointed a goodwill ambassador for an initiative aimed at protecting the Congo Basin Forest Ecosystem. In 2006, she was one of the eight flag-bearers at the 2006 Winter Olympics Opening Ceremony. Also on 21 May 2006, she was awarded an honorary doctorate by and gave the commencement address at Connecticut College. She supported the International Year of Deserts and Desertification program. In November 2006, she spearheaded the United Nations Billion Tree Campaign. Maathai was one of the founders of the Nobel Women's Initiative along with sister Nobel Peace laureates Jody Williams, Shirin Ebadi, Rigoberta Menchu Tum, Betty Williams and Mairead Corrigan Maguire. Six women representing North America and South America, Europe, the Middle East and Africa decided to bring together their experiences in a united effort for peace with justice and equality. It is the goal of the Nobel Women's Initiative to help strengthen work being done in support of women's rights around the world. In August 2006, then United States Senator Barack Obama traveled to Kenya. His father was educated in America through the same program as Maathai. She and the Senator met and planted a tree together in Uhuru Park in Nairobi. Obama called for freedom of the press to be respected, saying, "Press freedom is like tending a garden; it continually has to be nurtured and cultivated. The citizenry has to value it because it's one of those things that can slip away if we're not vigilant." He deplored global ecological losses, singling out President George W. Bush's refusal to join the United Nations Framework Convention on Climate Change (UNFCCC) and its subsidiary, the Kyoto Protocol. Maathai was defeated in the Party of National Unity's primary elections for its parliamentary candidates in November 2007 and chose to instead run as the candidate of a smaller party. She was defeated in the December 2007 parliamentary election. She called for a recount of votes in the presidential election (officially won by Mwai Kibaki, but disputed by the opposition) in her constituency, saying that both sides should feel the outcome was fair and that there were indications of fraud. In June 2009, Maathai was named as one of PeaceByPeace.com's first peace heroes. Until her death in 2011, Maathai served on the Eminent Advisory Board of the Association of European Parliamentarians with Africa (AWEPA). Wangari Maathai died on 25 September 2011 of complications arising from ovarian cancer while receiving treatment at a Nairobi hospital. CANNOTANSWER

What did she do after her time on as President?

In June 2009, Maathai was named as one of PeaceByPeace.com's first peace heroes.