The Geographers

Exponential Growth When a quantity increases by a constant amount per unit time  e.g. 1, 3, 5, 7, etc. it is called linear growth. But, when it increases by a fixed percentage it is known as exponential growth  e.g.  10, 10 2 , 10 3 , 10 4 ,………….., or 2, 4, 8, 16, 32 etc. Population growth increase in exponential rate and that explains the dramatic increase in global population in the past 150 years. Doubling Time The time needed for a population to double its size at a constant annual rate is known as doubling time. It is calculated as follows:             Td = 70/  r where  Td = doubling time in years                r =  annual growth rate If a nation has 2% annual growth rate, its population will double in 35 years. Total Fertility Rate It is one of the key measures of a nation’s population growth. TFR is defined as the average number of children that would be born to a woman in her lifetime if the age specific birth rate remains constant. Infant Mortal

Social Issues and the Environment Ghanashyam Deka Dept. Geography Q.1. The concept of Sustainable Development.   Ans. Sustainable Development is defined as “Meeting the needs of the present without compromising the ability of future generation to meet their own needs.” The definition was given by Norway ’s Prime Minister Brundtland, who was the director of the WHO. # The key aspects for Sustainable Development are (a) Inter-generational equity (b) Intra-generational equity. # Measures of Sustainable Development: Some of the important measures for Sustainable Development are as follows: (a) Using appropriate technology.                                                (b) Reduce, Reuse, Recycling approach.                                                (c) Environmental Education and Awareness.                                                (d) Resource Utilization as per Carrying Capacity.     Q.2. The Indian Concept of Sustainable Development.   Ans. In