Monday 22 December 2008

Note on The rainforests

*The tabled layered structure will not be shown here. Pls download the doc. file. Rainforests are dense vegetation covers in the hot and wet regions. There are certain characteristics of being a rainforests: 1) Many species -- over half of world’s species. 2) Layered structure 3) Equatorial climate, the temperature is high (25C or above), small temperature range (1~5C), averagely and large rainfall (2000mm) which means no dry season. Because of this reason, rainforest is found along the equator and within the Tropics of Cancer and Capricorn. The 3 biggest rainforest in the world is Amazon Basin in Brazil (1/3 of rainforest in the world), Congo Basin in Africa, and in Malaysia. It’s hot and wet climate favours the continuous growth of plants all year (evergreen) and various species of trees, insects and birds there. However, the rainforests are disappearing which called deforestation due to some reason. 1) Commercial logging -- Some tree are valuable to be logged. Those timber can be used for furniture and construction which have a large demand of wood. Modern machines used now increase the rate of deforestation. 2) Shifting cultivation -- the natives cut down the trees and burn to clear the area for farming which is called slash-and-burn cultivation. During their farming, they won’t irrigation and add fertilizer. Then after some time the fertility dropped. They will abandon the land and find a new plot. The abandoned land will be used after some time. The period is not enough for it to restore and allows trees to grow again. 3) Cattle ranching -- The land are also suitable for cattle ranching. Some American companies open extensive rainforest area as grassland for beef cattle. 4) Plantation agriculture -- The climate in rainforest are also favourable for planting cash crop which the product is valuable. 5) Population pressure -- the society development keeps on. This will increase the demand on land, transportation. Also, the government is in pressure for making economic growth. One of their way is to develop in rainforest. Thus some land is cleared for other uses. The deforestation affect serious to the local people, livings and us. 1) Deforestation increase the daily range of temperature, wind speed, decrease the humidity in the air and increase the rate of soil erosion. 2) The native people relies on the resources from the rainforests such as food and home. Deforestation will destroy their home, they have to migrate to other places and their culture destroyed. 3) Deforestation destroys the habitats and led to extinction on animals. 4) Leaves stops rainwater fall into the ground directly while the root bind the soil together and absorb water. Without them, soil and nutrients washed away to the river and forms alluvium. Then silting and flooding may occur. 5) Deforestation also decrease the rate of photosynthesis which takes in CO2 and output O2. CO2 is a kind of greenhouse gas that will reflects heat going out the atmosphere. This will amplifies the greenhouse effect and enhance the effect of global warming. Furthermore, flooding(the ice melts and rise of sea level), droughts in inland area(high evaporating rate) and extinction of wildlife occur more frequently. 6) It’ll also cause the loss of timber resources and valuable medicine. It’s hard to solve the problem because different people have different aim and view. 1) The government have to monitor plans for rainforest development and solve the conflicts. 2) Land developers, logging and mining companies only aim at profits, although they can provide jobs and funds, they show a little concern for the environment only. 3) The native people rely on the rainforest a lot so they totally oppose deforestation. 4) Those environmentalists mostly concerning about the rainforest environment so they press the development projects. Friends of the Earth and the World Wide Fund for Nature help building up natural reserves in the rainforests. To solve this problem , sustainable development is needed. 1) Afforestation project can be used for those area seriously affected by deforestation. Tree will be replanted for an extensive piece of area. 2) Selective logging is encouraged. The companies have to obtain a license before they exploit the timber in the rainforest and some tree can’t be cut. 3) Native people are encouraged to plant cover crops on abandoned land. Cover crop can protect the soil from heavy rain and help recovering the fertility of soil. 4) Eco-tourism is a kind of tourism that to respect and protect the nature and ecosystem. Some area is designed as protected areas, set up national parks or natural reserves in the rainforests where deforestation is not allowed there. We can also do something for the rainforest such as don’t but product made from endangered species, better use the rainforest products, support eco-tourisms and environmental organizations such as World Wide Fund of Nature, Green Power and the Friends of the Earth.

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