HKDSE Geography/M6/Natural Resource Extraction

Various forms of natural resource extraction are performed in the tropical rainforests.

Hunting and Gathering
Hunting and gathering refers to the collection of food resources, such as wild animals, fish, and plant parts (such as shoots and roots), mainly for consumption.

Hunting and gathering is not a form of agriculture as there is no growing or grazing involved.

Impacts

 * Hunting and gathering is originally a sustainable practice as the indigenous tribes of the tropical rainforests are scarce in number.
 * However, growing tribe populations have raised the level of destruction dealt by hunting and gathering, so their food sources are starting to thin out.
 * Some tribesmen and outsiders have begun to hunt endangered species such as the rhinoceros for commercial gain, threatening the biodiversity of the tropical rainforest in so doing.

Hydro-Electric Power
Hydro-electric power can be extracted from rivers in tropical rainforests.

Impacts

 * Aside from maintaining a steady supply of power, HEP has several other advantages: It facilitates navigation, prevents floods downstream, and so on.
 * However, damming destroys the river's local ecosystem and the habitats of the aquatic life which originally inhabited it.

The Itaipu Dam is a joint venture between Brazil and Paraguay. Its power generated exceeds even the Sanxia dam. It serves 75% of Paraguay's energy, as well as 17% of Brazil's. (Source)

Commercial Logging/Lumbering
Logging has always occurred in tropical rainforests as small amounts of wood are used as firewood for heating and fuelwood for power generation. They may also be burnt into charcoal and sold in local markets. However, in recent years, corporations have massively increased the scale of logging to produce expensive exotic woods in the tropical rainforests. The wood is made into various products, including paper, furniture and construction materials. Teak, rosewood and mahogany are examples of precious rainforest woods.

Impacts
The impacts of commercial logging will be discussed in the next chapter.

Mining
Two types of mining are commonly practised in tropical rainforests:
 * Alluvial mining refers to the extraction of minerals from alluvial deposits in rivers.
 * Opencast mining refers to the extraction of minerals in a pit.

Impacts

 * Alluvial mining pollutes rivers by disposing slag.
 * Opencast mining destroys a large area of the tropical rainforest as all the vegetation and the topsoil of the mining site is removed.
 * On-site refining of minerals releases poisons such as mercury and cyanide into the rainforest soil, posing a public health risk.
 * Mining disturbs the lives of tribespeople. Clashes between indigenous tribes and miners are frequent.

(Source)
 * 90% of the catch at Tapajós River have been found to be poisoned by mercury.
 * The Brazilian military had to forcefully eject gold miners from the forest as they were disturbing the local tribes.
 * 6100 sq. km of forest land is cleared every year in Carajas Mineral Province.