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DYNAMICS OF DEFORESTATION
Trees are vitally important to world health on all levels. Globally, forests are essential to the health of ecosystems and their functions, biodiversity and economics. Some of the many key functions of forests include climate regulation, the cycling and distribution of nutrients, and the provision of raw materials and resources. Trees cleanse the air and provide oxygen, help soil retain water, shield animals and other plants from the sun and other elements, and provide habitat for animals and plants. In addition, do not forget the special beauty they give us throughout each year!
From 1990 - 2000, about two percent of the world's forest cover - roughly 10 million hectares -was lost and not recovered, according the Food and Agriculture Organization (FAO). That rate continues today. Today there are approximately 100,000 known species of trees that exist throughout the world, according to World Resources Institute. A recent report from the United Nations Environment Program World Monitoring Center confirms that over 8,000 species are threatened with extinction and 976 of those are in a critical state. While trees were once spread virtually across all of Earth's landmasses, today they cover about 3.9 billion hectares or just over 9.6 billion acres (FAO Forest Resources Assessment 2000). One might think that's a lot of trees, but the fact is, trees now cover only about 29.6 percent of Earth's total land area. (It is important to note that these figures are not necessarily precise, they are the result of careful and comprehensive monitoring by field scientists worldwide. In as much the same way that it is currently impossible for us to know exactly how many animal species exist and have even died out without being discovered, it is also impossible to know exactly how many tree species currently exist or have existed on this planet.)
The process of natural selection for trees continues, but the advent of the Industrial Revolution created the foundation for exorbitant human demands of the land inhabited by trees. With the vast improvements in human health and technology, the human population would grow at a rate unparalleled by any other major land animal species in Earth's 4.5 billion year history. In addition, this would mean the demands for more resources from the Earth would increase exponentially. When you consider that the world population has grown by more than five billion people since the beginning of the Industrial Revolution, you can just imagine how much the world’s forests have been counted on to meet human needs!
As it is today, the forests were mostly converted for agriculture, housing and city expansion to meet the growing demands of the growing population.
The fact is, forests are being cut down and not replaced at a high rate in developing countries where their human populations are growing and their healthy development requires more use of land for agriculture, housing and roads, according to world Resources Institute. In the developing countries, even with replanting, there is a big net loss. Their population is growing fast; they are building their economy and growing food to support them. Some developing countries are also major producers and exporters of timber for industrial use.
ALTERNATIVES TO CUTTING DOWN TREES
While trees are a vital component in the creation of paper, many manufacturers today are beginning to use recycled waste combined with tree pulp to decrease the number of trees that need to be cut down and keep up with the growing demand for paper. Nearly half of all paper produced in the US is kept out of landfills by recycling it. Here waste paper has been sorted and prepared for recycling.
Recycling is by far the most common way to help save a tree. Some paper mills rely on recycled waste as their primary source of raw material. Others point ot agricultural waste as a stand in for wood. Agri-pulp, as it is called, is wheat, oat, barley and other crop stalks left over after harvesting. Combined with recycled paper and other fillers, some paper makers are finding that agri-pulp paper makes fine stationery.
Many environmentalists who believe that the world’s forests are being cut down faster than they can grow are pointing to the continued success of wood-free paper made with other plants such as hemp and a similarly fibrous plant called kenaf.
Hemp is a wood substitute that has a rich history in the paper making industry from paper's origins in China in the first century AD to the Declaration of Independence, which was written in the 18th century on hemp paper. Hemp is now used to make rope and clothes as well as paper. Unfortunately, it is illegal to grow hemp in the U.S. because it is a non-intoxicating variety of cannabis sativa; the same plant marijuana comes from. For that reason, hemp must be imported for use in the U.S.
The kenaf plant can quickly grow to between 12 - 18 feet in a few months. These plants provide about three-five times more fiber per harvest than southern pine trees, which can take 7-40 years before l hey can be harvested. This makes kenaf an attractive tree-substitute for making paper. This 4,000-year-old hibiscus plant - an annual, non-wood fiber plant related to okra and cotton - is native to central Africa and can grow up to 18 feet tall in a four-to-five month season. Like hemp, kenaf is naturally whiter than wood and can be bleached with hydrogen peroxide instead of chlorine.
One of the major reasons paper mills are hesitant to covert to using kenaf or hemp to make paper is because they are not set up to process anything except trees. Converting a paper mill to process these wood pulp alternatives would cost tens of millions of dollars and major coordination with their suppliers and customers.
The production and use of organic food products has taken firm root today as a serious alternative for consumers and farmers. Particularly since the early 1990s, a growing number of North American farmers have taken steps to minimize the use of, and consumers’ exposure to, toxic and persistent pesticides by establishing organic agricultural practices. Organic agriculture is a collection of tested agricultural practices by diligent farmers’ intent on preserving the health of our planet. Organic agriculture is sustainable, keeping soils healthy and alive, and helping to minimize contamination of the earth's precious water supplies.
Consumers who want to minimize their exposure to toxic and persistent chemicals can do so by buying organic foods and organic fiber products, and by choosing organic agricultural methods for home pest control and lawn care.
Despite the fact that less than 1 percent of U.S. agriculture research dollars are spent on organic practices, organic production has been shown to have yields comparable to, and sometimes higher than, conventional systems. In addition, because organic production improves soil quality as measured by soil structure, organic matter, biological activity, water infiltration and water-holding capacity, organic systems generally produce higher yields than crops grown using conventional high-input methods during drought, leading to production stability year after year.
Organic farming appears very much like traditional farming. The main difference is in the use of chemicals for treatment and nourishment. Organophosphates are not allowed in organic agriculture. Instead, organic growers use biological and cultural practices as their first line of defense against pests. Methods used include crop rotation, the selection of pest- and disease- resistant varieties, nutrient and water management, the provision of habitat for the natural enemies of pests, and release of beneficial organisms to protect crops from damage. Organic pesticides of molasses and enzymes are sprayed to ensure a healthy crop production.
Organic practices prohibit the use of genetic engineering, irradiation, sewage sludge, antibiotics, and hormones. These practices are allowed in other forms of raising and producing our food, and other agricultural products.
Because organic agriculture respects the balance of microorganisms in the soil, organic producers use composted manure and other natural materials, as well as crop rotation, to help improve soil fertility, rather than synthetic fertilizers that can result in an overabundance of nitrogen and phosphorous in the ground.
Current conventional practices have led to some measurable problems, including a high level of toxic metals in commercial fertilizers. An analysis of 29 fertilizers found that each contained 22 different heavy metals. In 20 of the products, levels exceeded the limits set on wastes sent to public landfills, with disturbing quantities of arsenic, lead, mercury, cadmium, chromium, and dioxin, among others.
Global Threat to Birds
Although birds can ride out extreme weather conditions and threats from natural predators, their greatest threat comes from loss of habitat, mainly due to human development and related activities. Forests and wetlands are vital to birds’ survival because they provide food and water, shelter, protection from predators and places for rest and food during their migrations. Over the past 100 years, much of the forests and wetlands have been depleted and thus seriously changed the landscape and resources for these migrating birds. As a result, bird numbers have been seriously affected in many parts of the worlds.
Of the 9,600 known bird species, nearly 1,200 are threatened with extinction (source: Johns Hopkins Center for Communications Program). About| 99 % of the globally threatened birds are risk from human activities such as agriculture, logging, hunting and trapping, other major changes in the world's ecosystems. The potential loss of large numbers of species facing extinction is a powerful indication that the quality of these ecosystem services is deteriorating.
In North America, for example, bird observers have seen a steady decline in the numbers of many of the birds that migrate to Central and South America. Deforestation and problems with their summer breeding habitats, urban sprawl and development, contamination of environment are significantly altering and removing valuable ecosystems on which birds depend. This is not only happening in the United States, but it is happening worldwide. In the US alone, this affects 80 percent the total bird population since about 520 of the US’ 650 bird species migrates.
Snow geese will fly all day and night, despite all conditions, until they reach the next suitablewetland area where they feed off the grass and small fish. Such areas have become more and more scarce in the past century, resulting in reduced numbers of snow geese.
Wetlands are areas that link water and land. They include a wide range of areas from marshes and swamps to areas between dry land and rivers, streams, lakes and coastlines. Though they are not necessarily wet year-round, they harbor very rich nutrients for plants and animals, including insects, which are a primary food for birds. Thus, wetlands provide vital habitat for many species of plants and animals, including about half of all known bird species.
As wetlands become fragmented and disappeared, the domino effect extends directly to respective qualities of life of humans and wildlife, as wetlands also provide needed protection of water quality vital for humans. They act as a sponge to absorb floodwaters, and they filter out impurities and pollutants that could flow into main water sources. Wetlands also serve to clean the air of carbon dioxide, which is absorbed by plants.
Armed with the comprehensive information now being collected about the world’s migratory birds, scientists hope to discover clues and develop solutions relating to Earth's environmental health.
New Fuel to Power the World Economy
The energy needs of increasing populations and growing economies can longer be met by uncertain supplies of oil. Recently the US, Japan, China and the European Union have focused on hydrogen technology as the most likely mainstay of continued economic development - and for good reason.
Hydrogen, the most abundant element in the universe, has excellent properties both as a fuel and as an energy carrier. When combined with a fuel cell, hydrogen offers quiet and highly efficient electricity production for both large and small applications. More significant is that it could pave the wave for zero-emission energy everywhere, from our homes to our cars. No single technology offers such broad opportunities.
Hydrogen fuel cell technologies are complex, but hydrogen has the potential for replacing essentially all gasoline and eliminating almost all C02 from vehicular emissions over the next 50 years. Hydrogen should be part of further research into all-electric vehicles, hybrids and synthetic fuels.
Substantial investment by automotive manufacturers, gas companies, the energy sector and governments has improved the performance of hydrogen fuel cell vehicles. Following the success of trials in Europe, fuel cell bus services are planned in some cities. Even with existing knowledge, any centrally fuelled commercial fleet could run on hydrogen in the near term. Fuel-cell-powered aircraft, trains, boats, trucks and forklifts are in development. The first in a new series of submarines, part-powered by fuel cells, has been launched by HDW, the shipbuilder. The number of cars is forecast to increase to more than 2bn by 2030, so initial sales of hybrid cars have demonstrated that there is already consumer demand for green technologies. Governments are right to pursue hydrogen as a potential replacement for car fuel.
Critics argue that hydrogen storage and production are not sufficiently developed for fuel cell vehicles to catch on and for these technologies to be economically viable. While hydrogen will have a role in the second half of the century, they argue, significant challenges need to be overcome. This is true -particularly for cars. However, raising cost objections to a technology that is still in the development makes little sense as the oil price climbs. If we leave decisions on an alternative to the second half of the century, it will be too late. Hydrogen is the most viable replacement. The initial hydrogen infrastructure would require 20 to 30 years' investment. The oil infrastructure - from rigs to petrol stations - may have served us for the last 80 years, but will have cost the world trillions of dollars. Every dollar spent on hydrogen will save us many more when the final rush for oil begins.