Using Examples Outline How the Tropical Grassland Ecosystem Works and Evaluate How It Can Be Managed

Using examples outline how the tropical grassland ecosystem works and evaluate how it can be managed.

The tropical grassland biome is situated between latitudes 5 degrees and 15 degrees north and south of the equator. Therefore it is found in the Brazilian Highlands, central Africa and northern Australia. With an exception of the grassland in East Africa, the savanna is bordered by desert on one side and tropical rainforest on the other.

The climate of a tropical grassland is significantly different to that of a tropical rainforest because the grassland experiences two distinct seasons. This is due to the movement of the inter-tropical convergence zone. This ITCZ is created by the Hadley cell, as above the equator intense solar heating takes place from the sun causing there to be great evaporation, as warm air can hold more moisture than cold air. As the water vapour rises and condense it coalesces to form large particles. When the particles get too big they fall as rain over the tropical grassland, as the air moves in convection currents. As the air sinks it warms again due to compression, however because the air has lost its moisture the warming process is more rapid. As a result there is great variance across the ecosystem. The grassland closer to the desert receives less rainfall and so shorter grasses grow compared to grasses that are closer to the equator. The two seasons are created as the ITCZ moves due to the earth rotating on a tilt.

In the dry season when rainfall is between 100-200mm only short grasses can survive because there is a soil moisture deficit. This dry season takes place between the 21st October and 21st April north of the equator as the ITCZ is not overhead. In the wet season the rainfall reaches 400mm, and so soil moisture recharge takes place. This allows solitary trees like the Baobab tree to survive as there is plenty of water available during this season, which takes place between 21st May and 21st September. The wet season is caused by the sun and ITCZ being overhead.

As a result of how the ecosystem works the tropical grassland biome is very fragile and therefore reaching a sustainable balance is very difficult in this ecosystem. The Serengeti is an area of tropical grassland in East Africa and there is a low level of economic development this makes it difficult to use the ecosystem sustainably. Currently the ecosystem is being used for hunting, land for the increasing population to settle on and land for growing crops. Although this is increasing the economic development of the area, the conservation of the ecosystem needs to be considered for the biome to be sustainable. As a result many management techniques have been put in place to establish an equal balance and to stop the exploitation of the ecosystem.

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