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To clear large amounts of forests


Farmland becoming deserts; man causes desertification by overgrazing.


Natural cause for famines; many years without rainfall.

Water pollution

Factories, animals, and human are polluting water sources; people upstream pollute water for people downstream.


A steep slope or long cliff that separates two relatively level areas of differing elevations.


An elevated, comparatively level expanse of land


The term for the flat, grassy, mostly treeless plain in a tropical grassland region.


The total market value of all the goods and services produced within the borders of a nation during a specified period. (Gross Domestic Product)

Literacy rate

The percentage of people over the age of 15 with the ability to read and write


The state of being or becoming a community with urban characteristics.

Ethnic group

People of the same race or nationality who share a distinctive culture

Oral history

Evidence taken from the spoken words of people who have knowledge of past events and traditions.

Extended family

A group of relatives, such as those of three generations, who live in close geographic proximity rather than under the same roof.


A large group of relatives, friends, or associates.

Middle passage

A large mass of water in the Atlantic, which was not affected by the slave trade.


A policy of racial segregation, practiced in the Republic of South Africa, involving political, legal, and economic discrimination against nonwhites.

Universal suffrage

The extension of voting privileges to all adults, without distinction as to race, sex, belief or social status.

Cash crop

A crop grown only for sale

Commercial farming

Farmers grow their crops to sell.

Subsistence farming

When farmers farm to survive and feed their family

Shifting farming

An agricultural practice using the rotation of fields rather than of crops.

Sedentary farming

When a farmer lives on the same farmland all his life


A rock layer that stores & allows water to pass through it


Water from an aquifer has reached the surface, supports vegetation and wildlife

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