Population Growth:

• The world population probably reached 500 million by 1650 and has since grown at an increasing rate. The world population first reached 1 billion in 1804. The second billion was added after 123 years in 1927.  Since 1950, the rise in population has been rapid.
• The growth of population or the natural increases of population depends on the birth rate and death rate. Birth rate is the number of live births in a year for every 1000 people in the total population. Death rate is the number of deaths per 1000 people.The difference between birth rate and death rate is termed as growth rate.

Population distribution and density:

• Population distribution refers to the pattern of spread of people on the Earth. World population distribution is uneven. About 90% of the Earth’s people live on 10% of the land.

Population density is defined as the number of people per sq.km.  it is calculated by dividing the number of people in a country by the area of that country.

POPULATION AND RESOURCES

• As the population grows, the resources base is struggling to provide human with their requirements. There is a mismatch of people and resources. The increased population puts a lot of pressure on the available resources like land and water.  Each year, the number of human beings increases, but the amount of natural resources with which to sustain this population remains finite.

Water:

• Water use has been growing at more than twice the rate of population increase in the last century. Freshwater constitutes barely 0.03% of the water that is available on the Earch’s surface. Increasing population overexploits and pollutes the surface and underground water.

Food supply and land availability:

• As population increases, food supply has to increase. In Africa and Asia, rural population nearly doubled between 1950 and 1985, with a corresponding decline in land availability.

Deforestation:

• Eighty percent of the world’s natural forests is destroyed by human development activities like logging, clearing for agriculture and grazing. Deforestation results in droughts, soil erosion, flooding, and global warming.

Desertification:

• A third of the Earth’s land surface (35%) is threatened by desertification. It affects a large number of people living in 110 countries. Decortications occurs in the semi – arid lands and desertification is impossible to reverse.

Minerals:

• As the world’s demand for minerals increase, minerals are being mined from greater and greater depths. This increases ground pollution and lowers the water table.

Fuel:

• About 80% of the world’s commercial energy comes from non-renewable fossil fuels like coal, oil and natural gas. The world’s use of fossil fuels has nearly doubled every 20 years since 1900. There is a decline in the availability of these fossil fuels.

Land Degradation:

• The land is degraded by a combination of human activities. The land, air and water are highly polluted.

Satellite Technology and Resources:

• As population increases, humans have to find ways and means of finding additional reserves of minerals and ground water. There is need for organized sharing of these limited resources for the benefit of human kind. This requires an understanding of the distribution and availability of natural resources over the Earth.
• The development of space technology after the World Wars opened up new ways of understanding the Earth’s resources. The first artificial satellite, Sputnik 1, was launched by the Soviet Union in 1957. This was followed by different countries for various purposes. These include Earth Observation satellites, Communication satellites, Navigation satellites, Weather Satellites and Research Satellites.
• Earth Observation satellites or Remote Sensing help in finding and managing resources. Remote sensing satellites play an important role in natural resources inventory, environmental monitoring and management. Important remote sensing satellites include LANDSAT of USA, SPOT of France, KITSAT of Korea and Yaogan of China.
• The first Indian Remote Sensing Satellite IRS1A was launched in 1988. This was followed by the launch of a series of other satellites like IRS – 1B, 1C, P3, P5, P6, CAROSAT and RESOURCESAT.
• The remotely sensed data provide valuable information about land resources such as geology, soil, vegetation cover, water bodies and minerals. This information helps countries to plan for a sustainable future.