Yet the mass destruction of trees—deforestation—continues, sacrificing the long-term benefits of standing trees for short-term gain. Since , the world has lost million hectares or about a billion acres of forest, according to the Food and Agriculture Organization of the United Nations —mainly in Africa and South America. About 17 percent of the Amazonian rainforest has been destroyed over the past 50 years, and losses recently have been on the rise. The organization Amazon Conservation reports that destruction rose by 21 percent in , a loss the size of Israel.
We need trees for a variety of reasons, not least of which is that they absorb not only the carbon dioxide that we exhale, but also the heat-trapping greenhouse gases that human activities emit. As those gases enter the atmosphere, global warming increases, a trend scientists now prefer to call climate change. Tropical tree cover alone can provide 23 percent of the climate mitigation needed over the next decade to meet goals set in the Paris Agreement in , according to one estimate.
An iceberg melts in the waters off Antarctica. Climate change has accelerated the rate of ice loss across the continent. Farming, grazing of livestock, mining, and drilling combined account for more than half of all deforestation. Forestry practices, wildfires and, in small part, urbanization account for the rest. In Malaysia and Indonesia, forests are cut down to make way for producing palm oil , which can be found in everything from shampoo to saltines.
In the Amazon, cattle ranching and farms—particularly soy plantations—are key culprits. Loggers, some of them acting illegally , also build roads to access more and more remote forests—which leads to further deforestation.
Forests are also cut as a result of growing urban sprawl as land is developed for homes. Not all deforestation is intentional. Some is caused by a combination of human and natural factors like wildfires and overgrazing, which may prevent the growth of young trees.
Yet, in Southeast Asia the green revolution is faltering in part because it is no longer possible to plant two or three crops per year. In some cases, water flow, due to rapid runoff, is deeper than. In Cambodia, fish yields of swamp forests can be 10 times higher than some of the best fishing grounds in the Atlantic. One strain of annual corn recently discovered in Mexican forests would revolutionize corn production by eliminating the need to plow and replant.
Essential for safe, reliable water supplies, forest cover also influences ground temperature, soil mixture and rainfall, regional weather patterns and global climate.
Floods and erosion will cause severe constraints on food production throughout the world before the end of the century by eroding topsoil, flooding rice fields, and filling in irrigation canals. Energy production has been reduced from many reservoirs because of siltation. For example the energy produced by the Mangla Reservoir Dam in Pakistan is reduced because of million tons of silt each year, four-fifths coming from the deforested Jhelum River watershed.
In Thailand, waterways that once provided energy efficient transportation are choked with silt and no longer navigable. Vincristine, made from a rainforest plant, now allows a child with leukemia an 80 percent chance of remission as compared with 20 percent in Tropical forests offer hope for other anti-cancer drugs, compounds for coronary disorders, and safer contraceptives.
The major cause of deforestation in the tropics is the need for food, fuel, shelter, and foreign exchange. The problems of converting forest areas for agriculture, fuelwood, and industrial logging are clues to more fundamental factors - problems of population pressure, unemployment, and inequitable land tenure.
Little can be done to slow global population growth for the next 50 to 70 years, by which time 12 to 16 billion people will inhabit the earth. In tropical countries, by the year , more than million people will be born annually. Land ownership is tremendously inequitable in developing countries. In Latin America, 7 percent of the landowners own 93 percent of the arable land as compared to the U.
During the last quarter of this century, annual, global wood needs are expected to double to just over 3 billion cubic meters.
During the same period, demand for pulp is expected to increase from million cubic meters to over million cubic meters.
Although tropical forests comprise 55 percent of global forest stocks, they contribute only 15 percent of the world trade in forest products. The Congo and Finland have land and forest areas roughly equivalent in size, yet in Finland exported forest products valued 60 times more. Amazonian countries have nearly three times more forest per person than the world average yet import more forest products by value than they export.
Tropical wood exports are the fifth largest export earner, excluding oil, amounting to 4 percent of all exports from the developing world. The demand for tropical hardwood in developed countries has increased by percent since while in tropical regions it has only doubled.
Eighty percent of all wood harvested in the tropics is used for firewood and charcoal. For some 2 billion people in developing countries 80 percent of all households , it costs nearly as much to heat their cooking bowls as to fill them. Pressure on the forest will only mount while petroleum prices remain high and populations grow.
In parts of Latin America and West Africa, the urban poor often spend a quarter of their income on wood or charcoal for cooking. In Kwemzitu, Tanzania, Anne and Patrick Fleuret report that a woman with a household of five must gather To keep pace with this consumption level villagers would need to plant trees every year. Small seminomadic groups of slash-and-burn agriculturalists in very large tracts of forest are probably beneficial to forest ecology.
View our Cookie Policy. I accept. Conversion of forests for other land uses, including pulp, palm, and soy plantations, pastures, settlements, roads and infrastructure. Forest fires: Each year, fires burn millions of hectares of forest worldwide. Fires are a part of nature but degraded forests are particularly vulnerable. These include heavily logged rainforests, forests on peat soils, or where forest fires have been suppressed for years allowing unnatural accumulation of vegetation that makes the fire burn more intensely.
The resulting loss has wide-reaching consequences on biodiversity, climate, and the economy. CLIL will no longer be a secret with"clil in action"!
Watch the lessons on physics, biology, earth science and chemistry, in CLIL mode, the result of the synergy of Eniscuola with the students and teachers of Italian schools. Improve your English with Smartenglish!
An online course, be used alone or in class, to complement the curriculum or to recover debits. An aid for students, a monitoring tool for teachers. Studying physics, biology, earth science and chemistry has never been so stimulating! Supplement the classroom lessons with those that Eniscuola has created for you with the teachers and students of Italian schools.
Projects involving students from around the world, of different ages, which allow students to learn new content and release their energy, through participation and discussion. A virtual thematic classroom, high school students linked from various parts of the world for 15 courses on the world of energy, organised by faculty of MIT in Boston and world-renowned experts. We are a partner of the NECST project , the European Union programme that connects schools in Croatia, Holland, Norway and Italy in the creation of a digital platform for research and exchange of knowledge on energy production.
A storyboard full of texts and drawings to narrate one's country in an original manner: letting loose the imagination of children around the world in the edition. And for the winners, production of animated short films! We have been speaking of sustainable behaviours to apply to our daily life, but what happens when we unplug and….
More than events were organised in 30 countries during the European Robotics Week November.
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