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Protect photosynthesis: less CO2 , more Oxygen and better health for all of us.
The impact of deforestation  Action concerning forests
Losses of biomass through deforestation and the cutting down of tropical forests put our supply of oxygen (O2) gas at risk. The Earth's forests did not use to play a dominant role in maintaining O2 reserves because they consume just as much of this gas as they produce. Today forests are being destroy at an astronomical rate. No O2 is created after a forest is put down, and more CO2 is produced in the process. In the tropics, ants, termites, bacteria, and fungi eat nearly the entire photosynthetic O2 product. Only a tiny fraction of the organic matter they produce accumulates in swamps and soils or is carried down the rivers for burial on the sea floor. The O2 content of our atmosphere is slowly declining. The content of the atmosphere decreased at an average annual rate of 2 parts per million. The atmosphere contains 210,000 parts per million. Combustion of fossil fuels destroys O2. For each 100 atoms of fossil-fuel carbon burned, about 140 molecules of O2 are consumed. Scientists will need to become more involved in assessing the viability of response options aimed at storing excess carbon in terrestrial or ocean systems. Land use changes from agricultural to forest ecosystems can help to remove carbon from the atmosphere at rates of 2 to 20 tonnes of carbon per hectare per year for periods of 50 years or more, until a new ecosystem equilibrium is reached. Similarly, soil conservation practices can help build up carbon reservoirs in forest and agricultural soils. Proposals to extract CO2 from smoke stacks and dispose of it in liquid form in underground reservoirs or deep oceans also need careful evaluation in terms of long-term feedbacks, effectiveness and environmental acceptability. However, much remains to be learned about the biological and physical processes by which terrestial and ocean systems can act as sinks and permanent reservoirs for carbon.
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Computer models have analized the Amazonian deforestation and indicated that the deforestation of a typical rainforest (air temperature 27oC, mean monthly rainfall of 220 mm) and subsequent degradation to savanna would result in:
Today about 1.8 billion people live in 36 countries with less than 0.1 hectare of forested land per
capita, an indicator of critically low levels of forest cover. Based on the medium population projection and current deforestation
trends, by 2025 the number of people living in forest-scarce countries could nearly double to 3 billion. Most of the world's original
forests have been lost to the expansion of human activities. In many parts of the developing world, the future availability of
forest resources for food, fuel and shelter looks quite discouraging. Future declines in the per capita availability of forests, especially
in developing countries, are likely to pose major challenges for both conservation and human well-being. The world's forests provide goods and services essential to human and planetary well-being. But forests are disappearing faster
today than ever before. Due both to deforestation and human population growth, the current ratio of forests to human beings is less thn half
what it was in 1960. Yet we not only need more forests, we need forests more than ever before–to protect the world's remaining plant and
animal life, to prevent flooding, to slow human-induced climate change, and to provide the paper on which education and communication still
depend. More efficient consumption of forest products and eventual stabilization of human population–a prospect that appears more promising today as birthrates decline–will be needed to conserve the world's forests
in the coming millennium. Half of the world's original forest cover is gone, a loss that reflects humanity's intensive use of land since the invention of farming.
Of the forest that remains, less than one-fourth could be considered relatively undisturbed by human activity. The vast primeval forests
of Europe and Asia survive today only as patchwork remnants of secondary growth, much of it vulnerable to logging, encroachment by development,
pollution, fire and disease. Forests are currently expanding in much of the industrialized world, while shrinking in most of the developing world. In just the first
five years of the 1990s, 65 million hectares of forest–an area the size of Afghanistan– were converted to other uses in developing
countries. By contrast, the industrialized countries gained 9 million hectares of forested land, an area about the size of Hungary. The pattern
of forest loss in developing countries today differs from past losses in Europe and elsewhere in two key respects: human populations are much
larger than before, and the pace of deforestation is more rapid. In the last four decades, an area half the size of the United States has
been cleared of tropical forests, while population in developing countries has doubled to 4.7 billion. Among the most encouraging trends for the
future of forests is the fact that fertility and birthrates are now declining in developing countries, leading demographers to revise downward
their projections of future population growth.Why population growth matters to the future of forests
In some countries, forests and other vegetation are being burned
away at alarming rates to satisfy the growing demand for agricultural land.
Population dynamics are among the primary underlying causes of forest decline. Poverty, corruption, inequitable access to land and wasteful consumption practices also influence the decisions of governments, corporations and individuals to cut and clear forests. The interaction of these forces is most evident in areas such as South Asia, Central America and sub-Saharan Africa, where poverty, rapid population growth and weak institutions contribute to forest loss and severe environmental degradation.
The dominant force in forest loss is growth in the demand for farmland. Subsistence agriculture is the principal cause of forest loss in Africa, Asia and much of Latin America. Slash-and-burn farming and other traditional techniques were sustainable for centuries when population densities were lower. Today they are a major factor, along with the expansion of commercial farms and livestock grazing areas, in the permanent conversion of wooded land to agriculture. The need to increase food production is expected to accelerate the forest-to-farmland cycle, especially in countries where alternatives for meeting this demand are limited.
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A typical American uses 15 times as much lumber and paper as a resident of a developing country. |
Total wood consumption has tripled during the 20th century. Per capita consumption has changed little on a global basis–actually decreasing slightly–but consumption patterns vary widely between countries. A typical American uses 15 times as much lumber and paper as a resident of a developing country. Reducing wood consumption in the industrialized world is unlikely to stop forest loss in developing countries however, since most of the wood consumed comes from trees in the industrialized countries themselves. Nevertheless, the consumption model offered to the rest of the world threatens accelerated forest loss as both populations and economies grow in developing countries.
Commercial logging of tropical forests has doubled since 1960, accounting for 5 million to 6 million hectares of forest loss each year, an area nearly the size of Sri Lanka. This is about one third the forest area lost each year in the developing world. Illegal logging causes a significant, though unquantified, amount of additional forest loss. Logging's biggest role in deforestation, however, is more indirect. Logging roads provide pathways deep into forests that farmers and other settlers then follow, permanently clearing the land for crops and pasture.
Nearly 3 billion people depend on wood as their main source of energy. The production of fuelwood and charcoal accounts for over 90 percent of the wood harvested in Africa, 80 percent in Asia and 70 percent in Latin America. Population growth is closely linked to rising woodfuel demand. The effects of woodfuel scarcity are most severe in impoverished areas, where more modern fuels are inaccessible or unaffordable.
Women and children are the victims of woodfuel scarcity. The search for fuel consumes the time, energy and health of women and their children. As local wood supplies grow scarce, women risk spinal column damage and uterine prolapse from carrying heavier loads over longer distances. Girls are often kept home from school to help their mothers gather wood, depriving them of educational opportunities. Where wood is unavailable, women cook with inefficient fuels such as animal dung or crop wastes, depriving livestock of fodder and soils of natural fertilizer. This endangers both the nutritional and respiratory health of women and their families.
Forest scarcity threatens the use of paper for education, the activity most likely to improve health and economic well-being. 80 percent of the world's population lack access to enough affordable paper and reading materials to meet basic standards for literacy and communication. Reducing paper consumption could help ensure enough paper for all. These efforts are undermined, however, by broader inequalities in access to education and economic opportunity. Closing the "paper gap" between rich and poor nations ultimately depends on government action to increase spending on education, health and social services in developing countries. Future population growth and forest loss will largely determine whether and when this gap can be closed.
Population policies based on human development and the Scale of Human and Earth Rights offer the greatest hope for the future of forests. This is not an argument for population "control" but for the social investments that allow couples to choose when to have children and how many to have. Programs linking conservation activities with family planning services show promise for achieving both the sustainable use of forests and greater acceptance of reproductive health services.
Sustainable wood consumption is essential for the future of forests. Individuals and institutions alike should promote the ecologically sound and socially responsible use of forest products. Eco-labeling, or the environmental certification of wood products, could speed the adoption of more sustainable forestry practices. Consumer demand for green-certified paper and other wood products is an important complement to recycling and other efforts to reduce wood consumption.
The well-being of the world's forests is closely linked to the health and well-being of women. Investing in education for girls helps them to contribute to their national economies–and to postpone childbearing until they are ready for a family. Providing credit and other economic opportunities for women creates alternatives to early and frequent childbearing. Finally, better access to quality reproductive health services directly benefits women and their families. These approaches increase human capacity, providing the greatest long-term return to societies, individuals and the environment. Moreover, they are likely to lead to an early peak in world population in the coming century–quite possibly at levels that can co-exist with forests that teem with human and non-human life for centuries to come.
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