Amazon+Landscape

Fill in all the gaps, using the words below, one word fits in each gap. Do in pencil. ** convectional economic sustained fluvial manioc environmental open-cast three transpiration Carajas Yanonami humus Trans-Amazonian Shifting burnt ash **
 * __ Answers __**
 * The effects of cultural perspectives and human activities on the natural landscape of the Amazon basin **
 * Gap-fill exercise **

Aluminium smelting || ** economic ** || Short-term and long-term devastating effects on the natural landscape. Rainforest clear- felled for **open-cast** mining and road/rail, soil exposed to wind and **fluvial** erosion, microclimates created. – hotter and drier due to removal of the forest ecosystem Land use ‘sacrificial’. Regeneration of natural landscape unlikely. ||
 * Group || Activities affecting the natural landscape || Their cultural perspective || Effects on the natural processes and elements of the natural landscape ||
 * Indigenous people e.g. **Yanonami.** || **Shifting** cultivation || Indigenous, **environmental,** sustainable || In the short term, vegetation is ‘slashed and burnt’, soil fertility increased by **ash**. Root crops (**manioc**, cassava) and fruit trees replace selva rainforest. Natural fertility of the soil exhausted after **3**years. Some localised soil erosion may occur. Area regenerates, so long-term effect on soil and vegetation minimal. The natural landscape is **sustained**. ||
 * Brazilian government || Built **Trans-Amazonian** Highway. Encouraged settlers from urban areas and more modern farming. ( cattle ranching, soy bean farming) || Economic and social || Road cut through rainforest, forest **burnt.** Reduction in **transpiration** reduced moisture for **convectional** rainfall, resulting in hot, drier climate in certain areas. Exposed soil washed and blown away. Soil fertility decreased. Loss of **humus** layer. Stock destroys soil structure. ||
 * Project **Carajas** || Mining iron ore, bauxite, gold.

 **__ Answers __**  ** Tectonic processes and the Amazon Basin **  ** Gap-fill exercise ** Fill in all the gaps, using the words below, one word fits in each gap. Do in pencil. ** American Andes Atlantic Brazilian crust denser downwards eastwards energy eroded flood plain fold geologic Gondwanaland Guiana Nazca plate sediment sedimentary soft South America steep west ** Tectonic processes have been very significant in the formation of the Amazon Basin. Although the basin itself is made up of eroded material or **sedimentary** rock, the direction and flow of the river is attributed to tectonics. The basin lies between three large relief features that were all formed by tectonic processes and from where the sediments that formed the basin therefore originated. To the north lies the **Guiana** Plateau while to the south lies the **Brazilian** Plateau. Both of these were once part of the ancient continent of **Gondwanaland**. This broke apart as a result of **plate** tectonics, which resulted in their present location in the continent of **South America**. As these ancient landmasses were broken down or **eroded**, the sediment formed the initial basin. This, however, flowed at this time in a **West** direction. It was only when plate movement caused the **NAZCA** plate moving eastwards to collide with the **American** plate moving westwards that this changed. The subduction of the much **denser** Nazca plate caused the land on top of the **crust** to buckle and **fold** to form the **andes** fold mountains. It also caused movement of land to the east of the mountains so it was pushed **downwards** to cause a basin. All of this meant that the Amazon River then changed course to flow in an **eastwards** direction and now have its mouth into the **Atlantic** Ocean. The Andes mountains also affected the river in other ways. Because they are recent in **geologic** time they are **soft** and easily eroded. This has created a lot of **sediment** that is deposited in the basin below and has built up a very wide **flood plain**. The **Steep** relief of the Andes also provides much of the **energy** for river flow. Without tectonics, the Amazon River would have very different characteristics.