the decline of population in rural areas and regions 

areas of high land which stick out into a steep-sided valley 

steep outer edge of a meander where erosion is at its maximum 

the change (an increase or a decrease) in population numbers resulting from the difference between birth and death rates over one year

the most important social, political and economic area of a country or global region - the centre of power 

a population in which there is a high percentage of people under the age of 16 (or sometimes 18)

the origins of an individual's or group's belief system 

precipitation formed when an air mass rises above a relief obstacle (mountains) leading to cooling and the condensation of water vapour

water that flows slowly through the soil until it reaches a river 

the inundation of low-lying areas in coastal areas and regions