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27
Deforestation

Deforestation through logging, burning, and clearing cultivation and pasturing (Smithsonian Institution/International Hardwood Products Association, 1990) is occurring rapidly in the tropics and involves heavy social and ecological costs, especially where the forests are cleared by burning, which releases CO2, CH4, and other greenhouse gases. Deforestation rates for the 1980s are uncertain: rates change rapidly, satellite coverage is spotty, and substantial (and expensive) verification is required. The best available analyses suggest many reasons for trying to limit the rate of deforestation, one of them being that deforestation accounts for 20 percent of the worldwide anthropogenic contribution to greenhouse warming (World Resources Institute, 1990). Where forests must be used, the goal is to practice what is called "sustainable forestry," in which harvesting practices maintain the forests and protect soil, water, wildlife, and future resources.

Recent Trends

Figure 27.1 illustrates how emissions of carbon to the atmosphere due to deforestation and changing land use have varied over time on the major continents (Dale et., 1991). The estimates are based on recent calculations by Houghton and Skole (1990) and Houghton (1991). Forests are cut for a number of reasons, including to provide land for agriculture and wood for wood products and fuel. Although the rate of deforestation in temperate areas is currently low, the deforestation of tropical countries is continuing. At one time, Europe and North America were experiencing net deforestation, but today this is negligible due to a number of factors, including resource depletion and sustainable management of what remains. A factor that has reduced pressure on remaining forests has been the movement of



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Page 424 27 Deforestation Deforestation through logging, burning, and clearing cultivation and pasturing (Smithsonian Institution/International Hardwood Products Association, 1990) is occurring rapidly in the tropics and involves heavy social and ecological costs, especially where the forests are cleared by burning, which releases CO2, CH4, and other greenhouse gases. Deforestation rates for the 1980s are uncertain: rates change rapidly, satellite coverage is spotty, and substantial (and expensive) verification is required. The best available analyses suggest many reasons for trying to limit the rate of deforestation, one of them being that deforestation accounts for 20 percent of the worldwide anthropogenic contribution to greenhouse warming (World Resources Institute, 1990). Where forests must be used, the goal is to practice what is called "sustainable forestry," in which harvesting practices maintain the forests and protect soil, water, wildlife, and future resources. Recent Trends Figure 27.1 illustrates how emissions of carbon to the atmosphere due to deforestation and changing land use have varied over time on the major continents (Dale et., 1991). The estimates are based on recent calculations by Houghton and Skole (1990) and Houghton (1991). Forests are cut for a number of reasons, including to provide land for agriculture and wood for wood products and fuel. Although the rate of deforestation in temperate areas is currently low, the deforestation of tropical countries is continuing. At one time, Europe and North America were experiencing net deforestation, but today this is negligible due to a number of factors, including resource depletion and sustainable management of what remains. A factor that has reduced pressure on remaining forests has been the movement of

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Page 425 image FIGURE 27.1 The annual net flux of carbon from the major continental areas. Source: Dale et al. (1991). population from rural to urban areas due to overall economic growth and the expansion of nonagricultural jobs. It should be noted, however, that because of industrialization, acid rain and other air pollutants are a serious threat to forests in some temperate areas (World Resources Institute, 1985). On the other hand, deforestation in many developing countries is believed to be increasing. As shown in Figure 27.2, recent estimates of tropical deforestation are larger than the 1981 to 1985 projection of the U.N. Food and Agriculture Organization. As indicated in both this figure and Figure 27.1, deforestation estimates very tremendously; it is not clear whether estimation techniques have changed or the rate of deforestation has increased. Table 27.1 shows the rate of deforestation for a number of developing tropical countries (World Resources Institute, 1990). Emission Control Methods Recently, a number of tropical forestry experts met to discuss the causes of tropical deforestation and what could be done to slow deforestation. They arrived at a number of conclusions, some of which are summarized below (Smithsonian Institution/International Hardwood Products Association, 1990):

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Page 426 image FIGURE 27.2 Area of closed forests cleared annually in selected tropical Countries, 1980s (in thousand hectares). (See Table 27.1 for the total of all tropical forest clearing.) Source: World Resources Institute (1990). • Tropical forests will be preserved only if they are accorded economic value. • Blanket bans and embargoes (in contrast to selective ones) on tropical hardwood will tend to depress the value of these hardwoods and the forests that contain them. Such constraints generally diminish the economic incentives to conserve and manage these forests in the face of alternative land uses that lead to their destruction. • In areas where prices received for timber do not fully cover the cost of forest management, there is a lack of incentive and commitment to forest management. • Funds obtained from products of the tropical forests must be rechanneled into managing and regenerating those forests. • The international tropical timber industry should encourage the continued establishment of conservation areas solely dedicated to forest preservation It is a challenge to understand the costs of limiting tropical deforestation and to finance such efforts. The Conservation Foundation (CF), World Wildlife Fund (WWF), and Fundacion Neotropica (FN) have proposed development of a ''forestry fund" through the use of conservation endowments (Conservation Foundation, World Wildlife Fund, and Fundacion Neotropica, 1988). A conservation endowment

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Page 427 TABLE 27.1 Deforestation of Closed Tropical Forests in Selected Countries Country FAO Annual Estimate 1961–1985 (thousand hectares) Annual Rate of Loss Based on FAO Estimate (%) WRI Estimate 1987 (thousand hectares) Annual Rate of Loss Based on WRI Estimate (%) Brazil 1,480 0.4 4,500a 2.2 Cameroon 80 0.4 100 0.6 Costa Rica 65 4.0 124 7.6 India 147 0.3 1,500 4.1 Indonesia 600 0.5 900 0.8 Myanmar (Burma) 105 0.3 677 2.1 Philippines 92 1.0 143 1.5 Thailand 379 2.4 397 2.5 Viet Nam 65 0.7 173 2.0   TOTAL 3,013 1.8 12,914 2.6 Total, all 11,400   20,400     tropical           countries         NOTE: Closed forests have trees covering a high proportion of the ground and grass does not form a continuous layer on the forest floor. Open forests have trees interspersed with grazing land. One thousand hectares (ha) is 10 km2. aThe World Resources Institute's original estimate of 8000 was based on 1987, which exhibited extremely anomalous conditions. Subsidies were scheduled for removal in 1988, driving up clearing, and a drought contributed to unusually high loss to fires. The total deforestation for the period from 1979 to 1989 has been estimated at 25 million hectares. The greatest deforestation occurred in 1987, and the rate in the latter half of the 1980s is probably closer to 4 million hectares per year. The actual deforestation is probably between 4 and 5 million hectares per year. No precise numbers are available. SOURCE: World Resources Institute (1990, p. 103). would provide a stable source of funding for long-term technical assistance and would support efforts to manage existing forest resources and to reforest degraded areas. Of particular interest are the portions of the plan that would attempt to (1) stop deforestation of currently protected areas such as parks and reserves through improved protection and management and (2) slow logging and clearcutting on private lands by providing technical assistance and incentives for both farmers and the commercial

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Page 428 sector to practice sustainable forestry (Conservation Foundation, World Wildlife Fund, and Fundacion Neotropica, 1988). The endowment would be created by placing $200 per hectare in a financial institution. The interest from that endowment would be used as a financial incentive for people living near the tropical forest to practice sustainable forestry. These people would maintain claim to both public lands and interest from the endowment as long as they practiced sustainable forestry. If they did not, funding would be withdrawn. The purpose of the endowment would be to compensate people for the additional income they would have received if they had continued to use current agricultural techniques (Conservation Foundation, World Wildlife Fund, and Fundacion Neotropica, 1988). A conservation endowment is being attempted in Costa Rica. The WWF has estimated that management and protection of the Golfo Dulce Forest Reserve and Corcovado National Park would save 8.7 Mt of carbon over the 10 years of the project.1These measures and others would provide a total carbon savings from the Costa Rican project of at least 21.8 Mt over 40 years (Conservation Foundation, World Wildlife Fund, and Fundacion Neotropica, 1988). The cost and carbon sequestration figures from WWF's estimates are extrapolated for the present rate of deforestation in Appendix O. Although these figures are obviously rough, they should provide some idea of the cost of implementing such an option. The results of this analysis indicate that at the present rate of deforestation the release of approximately 7000 Mt CO2 equivalent per year could be avoided. The cost of such a program would be approximately $0.40/t CO2 avoided. Barriers to Implementation Determining the cost and capacity of different methods for preventing deforestation is very difficult. It is one of the least certain of the various options examined in this report. The primary reason is that preventing deforestation involves changing the behavior of individuals in many developing countries. It is not something that the United States can pursue unilaterally, but rather will require careful attention to the needs and desires of a wide variety of people and cultures. It is important to realize that the pressures behind deforestation differ widely among the many tropical countries involved. There is no common cause, no common cure. Furthermore, government policies that tend to put low value on the benefits of intact natural forests, and high value on the benefits from forest exploitation and conversion, lead to deforestation without a full understanding of the biological impact. Some countries have exploited their tropical forest resources to solve fiscal, economic, social, and political problems

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Page 429 elsewhere in society (Repetto, 1988). The United States can act to prevent further degradation of its own forests, but in terms of affecting potential climate change, there are greater opportunities to be had in helping developing tropical countries to limit deforestation. Policy Options Integrating concern for the long-term sustainability of tropical forests into international economic development and U.S. foreign policy would help to advance forest protection. The economic development of tropical nations intersects in important ways with those nations' management of their forestlands. Tropical forests also hold a major share of the world's species. Until recently, exploitation of tropical forests has been regarded as a means for developing nations to obtain income from forested lands and space for expanded settlement. Increasing interest in the sustainable uses of forests, both to produce commodities such as rubber and to promote services such as ecotourism, reflects a growing appreciation of nondepleting use patterns as being valuable in their own right and as ways of attracting international assistance and investment. It should be noted, however, that exploitive uses such as logging provide near-term economic returns in an already well-established business setting and that the pressures of expanding populations are real. Both forest products firms—most of which are located in developed nations—and tropical nations are understandably reluctant to disturb activities that are profitable in the near term. Multilateral aid and technology transfer are likely to be necessary for forest protection for some time to come, because the costs of nonexploitive uses of forest resources are uncertain and high in some cases. This involvement tends to increase developing nations' concern that developed nations' environmental interest in the Third World may intrude on the developing nations' autonomy. A constructive step in this circumstance is to focus on concrete projects, in which the gains and risks to all participants can be gauged. Policies that focus on bilateral or multilateral efforts to develop ecotourism, for example, can be carried out without resorting to abstract principles of international equity. Similarly, review and revision of the tropical forest action plans advanced by the U.N. Environment Programme can stress the concrete over the abstract. Although it is uncertain at this time whether U.S. forests are a net source or a net sink for CO2, it appears that they are near equilibrium. Therefore, although deforestation is not a source of greenhouse gas emissions in the United States, forestry policy related to greenhouse could be enhanced by consideration of the global environmental impacts. These impacts have not been a component of U.S. forest management thinking, and the inclusion of

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Page 430 such considerations might not only enhance the role of U.S. forests in reducing greenhouse gas emissions, but also provide leadership for other nations. Other Benefits and Costs Tropical forests hold a major share of the world's species. Reducing deforestation can help maintain biodiversity. To put it simply, for the Amazon ecosystem to operate, it must maintain its wildlife and tree diversity. In addition, tropical forests provide soil protection, hydrological cycle balance, and products such as resins, essential and edible oils, fruits and nuts, natural fibers, and pharmaceuticals (Salati et al., 1989). The destruction of tropical forests is due to growing population, growing infrastructure, and the economic activities associated with certain occupations. Unless people who work in cattle ranching, timber extraction, farming, charcoal production, and gold or oil exploration can find an alternative source of revenue compatible with their skills, their income will drop and their country's subsequent economic development will suffer. Further, growing populations maintain pressures for homesteads, farmland, traditional fuel resources, and other land-based resources. Research and Development After studying deforestation in the Amazon, Salati et al. (1989) indicated the following problems: The lack of knowledge of the basic functioning mechanism of the Amazonian ecosystem and of the most suitable methods of sustainable development of the region are the main reasons for the failure of many of the agricultural and cattle ranging projects. In addition, institutional problems are serious. The lack of research funds is impairing the continuity of many research programs and also the implementation of technical recommendations and enforcement of legal exigencies. Their recommendations (Salati et al., 1989) include the following areas of research, which they believe are needed to adequately respond to deforestation: • An expansion of international support to research groups and institutions dedicated to the study of the basic functioning mechanisms of the ecosystem, especially those with programs under way for a considerable time. • The design of integrated interdisciplinary regional programs to study factors affecting the steady state equilibrium of the entire ecosystem. • The design of programs to reclaim already degraded areas, particularly through reforestation.

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Page 431 • The implementation of anthropology research programs designed to acquire better knowledge of the forest management practices of native peoples. We should not forget that they have been living in the forest and from the forest for thousands of years. • The stimulation of extractive activities for natural products, apart from logging, that have already proved to be economically profitable and cause no harm to forest integrity. In a broader geographic sense, it is important to understand both the variety of factors leading to deforestation throughout the tropics and the way in which countries such as the United States can contribute to solutions without challenging national sovereignty and sensibilities. Conclusion The causes of deforestation are many and varied and relate largely to population and economic pressures in developing tropical nations. To prevent deforestation over the long term, there will have to be alternative solutions for a variety of social and economic problems. Developed countries such as the United States may be able to help by providing a suitable financial setting, but they will have to be cognizant of the varying national needs, aspirations, and sensitivities. Note 1. Throughout this report, tons (t) are metric; 1 Mt = 1 megaton = 1 million tons; 1 Gt = 1 gigaton = 1 billion tons. References Conservation Foundation (CF), World Wildlife Fund (WWF), and Fundacion Neotropica (FN). 1988. The Forestry Fund: An Endowment for Forest Protection, Management, and Reforestation in Costa Rica. Washington, D.C.: World Wildlife Fund. Dale, V. H., R. A. Houghton, and C. A. S. Hall. 1991. Estimating the effects of land-use change on global atmospheric CO2 concentrations. Canadian Journal of Forestry Research 21:87–90. Houghton, R. A. 1991. Release of carbon to the atmosphere from degradation of forest in tropical Asia. Canadian Journal of Forestry Research 21:132–142. Houghton, R. A., and D. L. Skole. 1990. Changes in the global carbon cycle between 1700 and 1985. In The Earth Transformed by Human Action, B. L. Turner, ed. New York: Cambridge University Press. Repetto, R. 1988. The Forest for the Trees?: Government Policies and the Misuse of the Forest Resource. Washington, D.C.: World Resources Institute. Salati, E., R. L. Victoria, L. A. Martinelli, and J. E. Richey. 1989. Deforestation and its role in possible changes in the Brazilian Amazon. In Global Change and

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Page 432 Our Common Future, R. S. DeFries and T. F. Malone, eds. Washington, D.C.: National Academy Press. Smithsonian Institution/International Hardwood Products Association (IHPA). 1990. Tropical Forestry Workshop: Consensus Statement on Commercial Forestry Sustained Yield Management and Tropical Forests. Alexandria, Va.: International Hardwood Products Association. World Resources Institute (WRI). 1985. World Resources 1986. New York: Basic Books. World Resources Institute (WRI). 1990. World Resources 1990–91. New York: Oxford University Press.