{ TOC }-{ Chapter 1 }-{ Chapter 2 }-{ Chapter 3 }-{ Chapter 4 }-{ Chapter 5 }-{ Chapter 6 } Chapter 5: Losing Tropical RainforestsWhen thinking of the world as interwoven systems it’s easy to understand that places really remote from us can have rather direct effects on our daily lives. Most people in the United States don’t think of ecology in Brazil, New Guinea, or Australia as affecting them on a day to day basis. Think again. The Amazon basin is a vast expanse, more than 2.5 million square miles—an area almost as big as Australia—having the largest rainforest in the world. The Amazon river flows 3,000 miles from the Andes to the sea, longer than any river but the Nile. The Amazon River basin has varied types of environments that are home to literally millions of species. Over 1,000 species of butterflies alone have been recorded in the Amazon. It has several million animal species, mostly insects—and 3,000 known species of land vertebrates, as well as one fifth of the world’s bird species in less than 5% of the world’s land surface. About 80% of all known green plants are flowering plants (angiosperms), most of which are found in the tropical rainforests of the world. A small area of tropical rainforest may contain more than 750 types of trees and 1,500 species of higher plants.
At least 25 percent of all modern drugs originally came from rainforests. Scientists have identified over 2,000 tropical plants with anti-cancer properties. Many foods we consume, including rice, millet, bananas, oranges, pineapples, coffee, and tea, originate in rainforests. Rainforests are source of genetic material crucial to the sustained productivity of many modern crops.
The sheer number of trees in the Amazon basin act as a giant “carbon sink”, with all those trees dutifully capturing carbon dioxide from the atmosphere and converting it to carbon compounds embedded in the trees. Carbon dioxide, which humans produce at a rate of nearly six billion tons per year through burning of fossil fuels (gas, oil, and coal), is a key greenhouse gas, one of several gases that trap heat in the atmosphere, leading to global warming. [See GSS book: Climate Change for more about this topic.] Climate change could lead to a number of unpleasant effects ranging from rising ocean levels to increase in severity of storms and associated property damage. The ability of forests to act as a carbon sink could be one of many critical factors affecting the delicate balance of movement of carbon back and forth between solid compounds and gaseous forms.
Question 5.1.
Analysis of Deforestation in Rondonia
Start VegetationAnalysis and select the following three satellite images in this order:
Question 5.10.
Question 5.11.
Question 5.12. Be prepared to present your findings and conclusions to the class. What additional data would help complete any questions you still have about deforestation in this area of Brazil?
I. Competing Land Use Interests in the RainforestAdapted from: The Mandala Projects (American University, Washington DC); Trade and Environment Database (TED) Case Studies Some of the trees in the rainforest are rubber trees. The system of extracting rubber in this region was not one of plantation farming (cutting/harvesting) of the rubber trees, but rather rubber tapping in which slashes are cut into the tree and the sap is allowed to drain into a receptacle. The history of rubber tappers in Brazil has not been a particularly pleasant one. In the 1980s, Chico Mendes was the leader and political organizer of The National Council of Rubber Tappers, the union of the rubber tappers. Mendes tried to look out for the interests of rubber tappers: the trees. Without the rainforest there is no livelihood for them.
As large land owners, seeking profit, clear cut the forest to make pasture lands for cattle, Chico Mendes saw his means of living going up in smoke. The National Council of Rubber Tappers started non-violent resistance. When a crew of workers came to clear cut an area of the Amazon, a group of rubber tappers would surround them and not allow them to move until they turned over their chainsaws and other tools. These same chainsaws were then used to tear down the camps that had been set up. Ultimately the struggle led to a system of land use called an “extractive reserve” which set aside land for common use by people to take out products—not just rubber, but other things such as palm hearts and brazil nuts, without destroying the forest. The system supports the social well-being of the rainforest inhabitants, and the long-term sustainability of trade in forest products. But there are still great tensions between the cattle ranchers, settlers, loggers and the rubber tappers. Chico Mendes was shot and killed on December 22, 1988, presumably by a cattle rancher who wanted to protect his right to clear the rainforest. Darli Alves da Silva and his son, Darci, were convicted in December 1990 for the killing of Mendes. The effect was to make a martyr. International attention increased enormously. Even Hollywood got in on the scene to make a movie about Mendes’s life. Books were published telling his story. The World Bank and the Inter-American Development Bank became more concerned with the environmental impact of development. The events surrounding the life of Chico Mendes are seen as an environmental success story as well as a victory for social justice and dignity of the rural worker in Brazil. Yet in the years since the murder, ranchers and others have continued to clear the area in large swaths. In 1995, Brazil’s National Institute for Space Research, which tracks the burning of the rainforest, detected four times as many fires as it did in 1994. Dozens of rubber tappers and rain-forest activists allegedly have been abused, threatened and killed for speaking out against the special interests. Few arrests have been made in connection with those allegations.
II. Interview with an Amazon Forest Research Scientist
Dr. Nelson Dias is a Research Scientist at University of Taubat (Unitau), Taubat, SP, Brazil. Global Systems Science collaborator, Dr. Paul Mausel, Professor of Geography at Indiana State University, works with Dr. Dias and conducted the following interview March 10, 2004. PM: Approximately 15% of the Amazon Basin has been deforested. What are the major causes of this deforestation?
ND: New land is needed to support the population of the Amazon region that has grown from six million to twenty million people in the past 24 years. Agricultural, forest, and mineral extraction opportunities have greatly increased the past 30 years through road building, government support of settlers by providing free or low cost land, and other economic incentives. These actions have helped to make rapid population growth possible in the Amazon. PM: What is the current rate of deforestation and what are some of the consequences of this deforestation? ND: Currently, 15,000-20,000 sq. km of mature forest are being cut/burned in the Amazon each year (.4% - .5%/year of the total forest resource). Actual and potential consequences of excessive deforestation include:
ND: The are numerous possibilities, but one of the most common sequences of land use after deforestation is crop to pasture to initial forest succession (small trees mixed with some grass) to more advanced succession (full forest, but not as tall or diverse as the original forest), then back to mature or near mature forest. This full sequence of land use may be interrupted or have elements missing (e.g. crop to pasture to initial succession back to crop). In poor soil areas, a deforested mature forest may never return to its original state, but in good soil areas, a mature or near mature forests can develop in 50 years or so if left undisturbed after deforestation.
PM: Will all the original forests of the Amazon disappear? ND: Possibly, except for national parks, state parks, and other relatively small and protected areas. However, scientists from all over the world are conducting research that provides information and techniques that, if employed properly, have the potential to help create a sustainable land use whereby both vital economic growth and protection of most environmental elements can co-exist. This is a goal of many, but to what degree it will be achieved is uncertain.
PM: What are some of the characteristics of land use sustainability that permits reasonable economic uses and environmental needs of the land to co-exist?
ND: Sustainability means different things to different people, but many scientists and environmental planners have suggested that some of the elements associated with sustainability are that
III. Summary of Rainforest IssuesAdapted from: The Mandala Projects (American University, Washington DC), Trade and Environment Database (TED) Case Studies, Brazil Deforestation and Logging, http://www.american.edu/ted/brazil.htm. Deforestation in the Amazon Basin is caused by human activities such as agriculture, cattle ranching, logging and local demand for fuelwood. Trade may also play an important role both in destroying the rainforests and possibly saving them. The United States and Europe are the largest importers of rainforest products (wood, nuts, rubber, ...). Though deforestation is the major problem, other related problems include: (a) Global Warming: Deforestation in developing countries accounts for between 7 and 31 percent of global carbon dioxide emissions which cause climate change. (b) Indigenous Tribes: There were hundreds different types of indigenous tribes in the Amazon. Between 1900 and 1957 about eighty tribes had been destroyed and the number of indigenous peoples dropped from one million to two hundred thousand. The Amazon basin held most of the remaining tribes (some 140 tribes). These too could become extinct if their land is taken away. (c) Bio-diversity: Northern Brazil is losing natural forests with the substitution of fast-growing eucalyptus and pine trees, cattle ranching and commercial logging. (d) Species Loss: Much of Brazil’s native flora, fauna and animal species are being lost with the harvesting of tropical forests. Globally, forests cover about 7 percent of the planet’s land surface, but they are home to 50 percent of the plants and animals found on Earth. As many as 27,000 species may go extinct every year. These extinctions have philosophical, spiritual, cultural, scientific and economic impacts. Because Brazil has the highest species diversity on the Earth, it is an epicenter of efforts to control deforestation. The theory behind sustainable rainforest harvest is that forests are of more value when left standing than when they are felled. This value can be expressed in the commercial value of forest products (e.g. fruits, nuts, and cosmetic oils). A study done on the value of the fruits, latex, medicinal herbs, essences and oil discovered that in the long run investment in these products were more profitable than either logging or cattle ranching.
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