https://youtube.com/watch?v=M4jhjt1_eyM+
Excerpt From: Rischard, Jean-Francois.
“High Noon: 20 Global Problems, 20 Years To Solve Them.” iBooks.
“The same can be said for another threatening global commons issue—the loss of forest cover and the advance of deserts and savannas the world over.
Few of us realize how central a role forests play. Along with woodlands and scattered trees, forests provide the planet’s population with shelter, food, fuelwood, medicines, building materials, and paper. They contribute to freshwater quality by slowing land erosion and filtering pollutants—and they regulate the timing and rate of water flow. About two-thirds of all terrestrial species are in forest areas, which are thus critical to biodiversity conservation. And when forests grow, they sequester carbon—so they are a crucial part of the fight against global warming.
What’s the global situation? Today, about 30–35 million square kilometers of forests remain, or about 25 percent of the world’s total land surface—probably down 20–50 percent from pre-agricultural times, though no one knows exactly. Forests in industrial countries have increased slightly over the past decades, but their trees are getting younger, smaller, and less diverse.
But the real problem is in developing countries, where there are several types of issues:
Their forests have been shrinking by more than 130,000 square kilometers (or close to 1 percent) a year. Some 20 percent of tropical and subtropical forests have disappeared since the 1960s. In Indonesia alone, for example, deforestation has run at 17,000 to 20,000 square kilometers a year over the last decade, shrinking its forest cover more than 50 percent since 1985; at the going rate, Kalimantan’s forests will disappear in nine years and Sumatra’s lowland forests in four. The main reasons behind this worldwide trend are the pressure of population growth, leading to an expansion of subsistence agriculture and to unsustainable fuelwood collection; large-scale cattle ranching in Latin America; government-planned settlement schemes; and illegal logging. In Indonesia, 70 percent of log production is derived from illegal sources.
Forest fragmentation—by roads, agriculture, and logging—also has a large negative impact. It reduces the natural habitat, blocks migration routes, and opens avenues for undesirable foreign species. Roads provide access for hunting, timber harvesting, and other disturbances to the local ecosystem. And where fragments are too small to support top predators, cascade effects degrade diversity.
Forest fires appear to be on the increase. While forest fires can be a natural and useful phenomenon, Brazilian wildfires increased 50 percent in 1996–1997, and again by 80 percent in 1997–1998. Recent giant fires in Southeast Asia caused respiratory problems for 20 million people and several billion dollars in damages—Indonesia lost 46,000 square kilometers of forest in 1997 alone.26 The El Niño phenomenon was part of the story.
All these factors combine to turn the future of tropical and subtropical forests into an important global issue. It has several dimensions:
Timber production has increased 50 percent since 1960. With plantations providing 20 percent of all timber, scarcity is not a global problem in itself. The worry is that the spread of tree farms hasn’t reduced the pressure on natural forests. In many developing countries, trees continue to be harvested at a much faster rate than natural regrowth. Typically, once forests are cleared, the land is eventually converted to other uses, in a self-reinforcing cycle. Illegal logging by major groups and by farmers using slash-and-burn techniques is a major culprit.
https://youtube.com/watch?v=jHQGyMBtE9Y+
Fuelwood, along with charcoal, accounts for half the world’s biomass energy use—on which 2 billion people in the developing world depend—and 30 percent of the world’s total energy consumption. It is already becoming scarce in some regions, particularly near urban centers. With the coming population increase almost entirely in the developing world, fuelwood demand could easily exceed by 50 percent or so what can be sustainably supplied.
Forest loss has eroded the capacity of the world’s forests to retain and filter water, and to regulate its flow. Forests are most crucial in the watershed areas—but nearly 30 percent of those areas have lost three-fourths of their original forest cover. Since forests also tend to moderate runoff during rains and thaws, their loss makes mudslides and downstream flooding more frequent—Himalayan forest losses have made life much harder in lower-lying Bangladesh. And since they also release water during drier times, their loss also makes drought situations worse.
As forests go, so goes biodiversity. Forests need protecting for the sake of diversity itself and because they have become a major source of new goods and services—including pharmaceuticals, industrial raw materials, and revenue-earning tourism and recreation services. Already, close to 10 percent of tree species are threatened with global extinction, and the invasion of foreign species has become a problem in many places.
Forests store more carbon than any terrestrial ecosystem—perhaps 40 percent of all carbon is stored that way. Clearing tropical forests and burning the debris releases large amounts of carbon back into the atmosphere as carbon dioxide. Beyond large-scale forest clearing, even logging and clearing small areas of forest for agriculture significantly reduces its carbon storage capabilities. Restoring degraded forests or changing their management is a major avenue for carbon sequestration and one of the strategies for addressing global warming.
Many solutions exist, as the considerable success of plantations shows—they produce 20 percent of the world’s timber on only 3 percent of the forest area. And many sustainable forestry options have been developed over the years, with the best involving local participation by villagers or, as in India’s Ahmedabad, even town dwellers. We must also develop a potent certification mechanism for sustainable forestry and fight illegal logging at a global level.27
Deforestation is another global issue, with huge stakes for the planet, whose solution isn’t that expensive or technically complex. Yet we’re far from having made a real dent.”