Human activity can impose far-reaching effects on an ecosystem. There is a potential conflict of interest between production and conservation.
Deforestation occurs when the world’s forests are chopped down, burned, or destroyed. This is done to clear land for agricultural purposes such as for grazing animals and growing crops but also for commercial logging purposes where the wood is sold as timber or pulp. This world wide problem occurs most often in tropical forests which are situated I relatively poor countries such as Brazil which hosts the Amazon rainforest.
In 1995 Brazil had an international debt of $159 billion, in order to make the payments on this the logging industries contribute money made from selling pulp and valuable hardwoods such as mahogany. Also farming is the basic way of life for many of the Brazilians and for this they need land, which is in turn taken from the tropical forest. The Food and Agriculture Organisation (FAO) estimate that 53 square miles of tropical forest were destroyed each year during the 1980’s with 21,00 square miles of this coming from the Amazon basin (website 1).
Logging and clearing can cause many problems on the remaining land and for the wild animals losing their natural habitats. It can cause desertification and land slides because of the loss of structure in the ground from the root systems of the removed trees also it leaves the ground with no nutrients as they are all stored in the roots and trunks of the trees. This means that regrowth of the natural forest is very difficult also the use of the land for farming is almost useless. Even when the ‘slash and burn’ method is used which burns the organic material to release the nutrients it doesn’t last for very long because as soon as it rains the lack of structure in the soil means that the top soil which contains the nutrients is washed away.(website 2) In these cases the land is often abandoned after a few years leaving it to become natural forest however with the low nutritional content of the soil the wild plants take a long time to regrow also any insecticides left on the land by the farmer can affect the local wildlife and weaken ecosystem health. Also the lack of structure in the soil can cause landslides, which can cause silting in rivers, this is when rivers are filled with mud. This often blocks out the light killing the plants and animals.(Encarta encyclopaedia)
