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Rain Forest Essay, Research Paper
As much as people like to belive they know what a “rain forest” is, the truth of the matter is one in which not even professionals that deal with the forests on a dailty basis can surmise with articles and essays. As we look deeper and deeper into the intricate systems of our worlds rain forests, we must first differentite between forests, explorer the imense significants each role plays, and to carefully examine human interaction with them.
Rainforests are classified by climate, altitude, and latitude, either alone or in cobination. The equatorial rainfoest refers to forests found in the equatorial zone 10 degrees either side of the equator . In cases where the rain forest extends beyond the tropics, it is refered to as the subtropical rain forest. In areas that experience pronounced changes in season, a cycle of wet and dry seasons, the forests are classified as monsoon rain forests . Rain forests that establish themselves on tropical mountains are called montane rain forests; However all of thses rain forests can be easily classified into two distinct groups; Tropical, and Temperate. Tropical rain forests are chacterized by broad leaf evergreen trees that form a closed canopy . Below the canopy is a network of vines and epiphytes, which are plants that grow of the trees. Tropical rain forests also have a relatively open forest floor, and a lage variety of plant and animal species. The largest areas of tropical rain forests are located in the amazon basin of South America, in the Congo basin and lowland eqatorial regions of Africa, and on both the mainland and the islands off of Southeast Asia, in small areas found in Central America and along the Queensland coast of Australia. Temperate rain forests, growing in higher-latitude regions having wet, maritime climates, are less extensive than thoae of the tropics but include some of the most valuable timber in the world. Temperate forests are found on the northwest coast of North America, in southern Chile, Tasmania, and in parts of southwestern Austrailia and New Zealand. They contain trees that exceed the height of those in tropical rain forests, but there is less diversity of species.
Rain forests cover less than six percent of the Earth’s total land surface, but they are home for up to three-fourths of all known species of plants and animals, they also contain many more species that have yet to be discovered. Rain forests are of more potential value on a long-term basis when keft more or less intact than when converted to pastures or other simplified habitats. Rain forests have built up the largest standing trees of any plant community on earth , and they have done this almost independant of soil conditions by recycling nutrients. Managed rain forests can provide huge amounts of valuable timber, retain the naturally thin topsoil layers, regualte runoff, and stabalize localclimate. Because rain forests contain the earth’s graetest diversity of plants and animals, they also represent giant gene banks that can proviede new drugs, food, and other products. Only a very small percentage of rain forest plants have been assayed for potential chemial value.
Throuought history, humans have invaded on rain forests for living space, timber, and other agricultural puposes. There are a large number of natural phenomena and human activities that have had an impact on rain forests, lightning fires, disease, and other natural forces are now of minimal influence compared to human activities such as logging, road building, and large-scale clearing for cattle pasture and other agricultural crops. The large-scale clearing that takes place in nearly all rain froest areas is so extensive that hundreds of years would probably be needed for anything resembling the original vegetation to return. In tropical rain forests the practice of “shifting cultivation” has caused deterioration of the primary forest. Trees are killed in small plots that are cropped for two or three seasons and then abandoned; if the plots are recultivated before primary vegetation has reestablished itself, a progressive deterioration of the forest results. Since the 1970’s the rate of tropical deforestation has accelerated graetly. Total rates of tropical deforestation are difficult to estimate, but probably 100 000 sq km of rain forest are destroyed or seriously degraded every year. Some highly unique rain forests have been almost totally destroyed. Logging for exotic tropical wood has grown extensively in recent decades, leading to deforestation in places msuch as Brazil, Central America, and Malaysia. Temperate rain forests in British Columbia are also in danger from logging.
As we now see the significant role that these forests play, and the reality that some of these regions are not so far a way form home; We must insure that these last few remaining areas of earth are not exploited economicaly, before inadiquately unexploited scientificaly. The consequences could be dissaterous!
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