Wangari Maathai (born April 1, 1940, Nyeri, Kenya—died September 25, 2011, Nairobi) was a Kenyan politician and environmental activist who was awarded the 2004 Nobel Prize for Peace, becoming the first Black African woman to win a Nobel Prize. Her work was often considered both unwelcome and subversive in her own country, where her outspokenness constituted stepping far outside traditional gender roles.
Maathai was educated in the United States at Mount St. Scholastica College (now Benedictine College; B.S. in biology, 1964) and at the University of Pittsburgh (M.S., 1966). In 1971 she received a Ph.D. at the University of Nairobi, effectively becoming the first woman in either East or Central Africa to earn a doctorate. She began teaching in the Department of Veterinary Anatomy at the University of Nairobi after graduation, and in 1977 she became chair of the department.
While working with the National Council of Women of Kenya, Maathai developed the idea that village women could improve the environment by planting trees to provide a fuel source and to slow the processes of deforestation and desertification. The Green Belt Movement, an organization she founded in 1977, had by the early 21st century planted some 30 million trees. Leaders of the Green Belt Movement established the Pan African Green Belt Network in 1986 in order to educate world leaders about conservation and environmental improvement. As a result of the movement’s activism, similar initiatives were begun in other African countries, including Tanzania, Ethiopia, and Zimbabwe.
In addition to her conservation work, Maathai was also an advocate for human rights, AIDS prevention, and women’s issues, and she frequently represented these concerns at meetings of the United Nations General Assembly. She was elected to Kenya’sNational Assembly in 2002 with 98 percent of the vote, and in 2003 she was appointed assistant minister of environment, natural resources, and wildlife. When she won the Nobel Prize in 2004, the committee commended her “holistic approach to sustainable development that embraces democracy, human rights, and women’s rights in particular.” Her first book, The Green Belt Movement: Sharing the Approach and the Experience (1988; rev. ed. 2003), detailed the history of the organization. She published an autobiography, Unbowed, in 2007. Another volume, The Challenge for Africa (2009), criticized Africa’s leadership as ineffectual and urged Africans to try to solve their problems without Western assistance. Maathai was a frequent contributor to international publications such as the Los Angeles Times and the Guardian.
deforestation, the clearing or thinning of forests by humans. Deforestation represents one of the largest issues in global land use. Estimates of deforestation traditionally are based on the area of forest cleared for human use, including removal of the trees for wood products and for croplands and grazing lands. In the practice of clear-cutting, all the trees are removed from the land, which completely destroys the forest. In some cases, however, even partial logging and accidental fires thin out the trees enough to change the forest structure dramatically.
History
Conversion of forests to land used for other purposes has a long history. Earth’s croplands, which cover about 49 million square km (18.9 million square miles), are mostly deforested land. Most present-day croplands receive enough rain and are warm enough to have once supported forests of one kind or another. Only about 1 million square km (390,000 square miles) of cropland are in areas that would have been cool boreal forests, as in Scandinavia and northern Canada. Much of the remainder was once moist subtropical or tropical forest or, in eastern North America, western Europe, and eastern China, temperate forest.
The extent to which forests have become Earth’s grazing lands is much more difficult to assess. Cattle or sheep pastures in North America or Europe are easy to identify, and they support large numbers of animals. At least 2 million square km (772,204 square miles) of such forests have been cleared for grazing lands. Less certain are the humid tropical forests and some drier tropical woodlands that have been cleared for grazing. These often support only very low numbers of domestic grazing animals, but they may still be considered grazing lands by national authorities. Almost half the world is made up of “drylands”—areas too dry to support large numbers of trees—and most are considered grazing lands. There, goats, sheep, and cattle may harm what few trees are able to grow.
Although most of the areas cleared for crops and grazing represent permanent and continuing deforestation, deforestation can be transient. About half of eastern North America lay deforested in the 1870s, almost all of it having been deforested at least once since European colonization in the early 1600s. Since the 1870s the region’s forest cover has increased, though most of the trees are relatively young. Few places exist in eastern North America that retain stands of uncut old-growth forests.
Modern deforestation
The United NationsFood and Agriculture Organization (FAO) estimates that the annual rate of deforestation is about 1.3 million square km per decade, though the rate has slowed in some places in the early 21st century as a result of enhanced forest management practices and the establishment of nature preserves. The greatest deforestation is occurring in the tropics, where a wide variety of forests exists. They range from rainforests that are hot and wet year-round to forests that are merely humid and moist, to those in which trees in varying proportions lose their leaves in the dry season, and to dry open woodlands. Because boundaries between these categories are inevitably arbitrary, estimates differ regarding how much deforestation has occurred in the tropics.
A major contributor to tropical deforestation is the practice of slash-and-burn agriculture, or swidden agriculture (see alsoshifting agriculture). Small-scale farmers clear forests by burning them and then grow crops in the soils fertilized by the ashes. Typically, the land produces for only a few years and then must be abandoned and new patches of forest burned. Fire is also commonly used to clear forests in Southeast Asia, tropical Africa, and the Americas for permanent oil palm plantations.
Additional human activities that contribute to tropical deforestation include commercial logging and land clearing for cattle ranches and plantations of rubber trees, oil palm, and other economically valuable trees.
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The Amazon Rainforest is the largest remaining block of humid tropical forest, and about two-thirds of it is in Brazil. (The rest lies along that country’s borders to the west and to the north.) Studies in the Amazon reveal that about 5,000 square km (1,931 square miles) are at least partially logged each year. In addition, each year fires burn an area about half as large as the areas that are cleared. Even when the forest is not entirely cleared, what remains is often a patchwork of forests and fields or, in the event of more intensive deforestation, “islands” of forest surrounded by a “sea” of deforested areas.
The commercial palm oil industry rapidly expanded in the late 20th century and led to the deforestation of significant swaths of Indonesia and Malaysia as well as large areas in Africa. New plantations are often formed using slash-and-burn agricultural methods, and the resulting fragmentation of natural forests and loss of habitat threatens native plants and animals. Bornean and Sumatran orangutans are especially iconic species threatened by the expansion of oil palm farming in Indonesia.
Deforested lands are being replanted in some areas. Some of this replanting is done to replenish logging areas for future exploitation, and some replanting is done as a form of ecological restoration, with the reforested areas made into protected land. Additionally, significant areas are planted as monotypic plantations for lumber or paper production. These are often plantations of eucalyptus or fast-growing pines—and almost always of species that are not native to the places where they are planted. The FAO estimates that there are approximately 1.3 million square km (500,000 square miles) of such plantations on Earth.
Many replanting and reforestation efforts are led and funded by the United Nations and nongovernmental organizations. However, some national governments have also undertaken ambitious replanting projects. For example, starting in 2017, the government of New Zealand sought to plant more than 100 million trees per year within its borders, but perhaps the most ambitious replanting project took place in India on a single day in 2017, when citizens planted some 66 million trees.
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