HUMAN POPULATION & ENVIRONMENT

HUMAN POPULATION & ENVIRONMENT :=INTRODUCTION :-Population can be defined as a group of organisms of the same species occupying a particular space at particular time.The population has doubled since 1950 to the present level.The growth of population accelerated after the industrial revolution in the 19th century.After 1950, it increased at a very fast rate to reach the present levels.Population Table :- Country population in million China 1330 India 1173 U.S.A 310 Indonesia 242Brazil 201Pakistan 177Bangladesh 158 % of world Rank Population 19.5 1 17.3 2 4.5 3 3.5 4 2.8 5 2.5 6 2.4 7Population Growth Formulas :- The change in Population per unit area at particular time is called population growth.

population growth rate = [crude birth rate crude death rate] 100 1000Growth Ratio = growth rate 100%4

Population Growth Graph Malthusian Theory => The English political economist and demographer the revered Dr. Thomas Robert Malthus published his treatise Essays on the principles of population in 1798.

The Malthusian theory is based on the following assumptions :-

=> The food is necessary for survival of man and therefore their existence.

=> Population, if unchecked, increases at a faster geometric rate.

Time (t)Population (N1)Malthusian Theory Graph Different Human settlement are :- Land Food Water Energy resources Forest resources Shelter Air Land := As population increased, people started taking over more & more land for human settlement. They construct roadways,railways,public complexes & industries. Food := Ancient man was depended on animals for food. They does hunting of animal for their food.

As a population increased, demand for more land for agriculture also increased. Water := As the population increased, due to shortage of water and also due to pollution of surface water bodies(like rivers, lakes, ponds)people started the use of ground water in terms of open wells for drinking water purposes.

Energy resources:=Earlier man was using fire for cooking food in forests. They started using animals as a means of transport But, with increase in population the use and demand of conventional energy sources (oil, petrol, gas, diesel, etc.) has considerably increased leading to depletion of these sources.Forest resources:=Earlier man started living in forest as the food was easily available, with increase in population demand of more land human settlement & agriculture also increased. This is very serious effect on wildlife. Shelter:=Earlier man started living in forest, he moves to caves. With increase in population people started settling by constructing huts, small colonies, etc. these colonies expanded to present village, town & cities.Air:=Air is the basic requirement for men. Earlier days there was not a problem of fresh air. But today due to excessive air pollution the air quality has deteriorated. The people search to settle themseleves in pollution free atmosphere. Factors affectingpopulation growth rate:- Basic four factors in population growth :- Birth rate & mortality fertility migration age structure Birthrate & mortality:= Birth rate is the number of child birth per Thousand people, per year. Mortality rate is the number of deaths per 1000 people per year.Fertility:= fertility is the capability of reproduction of human beings.Totle fertility rate :- Totle fertility rate is the average number of children born to woman during her life time. in developed countries TFR= 1.6 in less developed countries=3.5 Migration:= It is movement of Individuals into or out of a place or country. Net immigration which may be positive, negative or zero is only responsible for change in growth rate.Age structure:= The age structure of a given population refers to the number of individuals of different ages within that population. Three groups based on age:= Pre-reproductive group = 0-14 years reproductive group = 15-44 years post-reproductive = 45 years & aboveEffects of Population :-Decrease in agriculture landReduction in living standard of peopleIncrease in migration rateIncrease in unemploymentEnergy crisisHigh crime rateLow per capita incomeControl of Population explosion:-Education Living standards & employmentGovernment benefitsPublicityParticipation of NGOs (Non-government Organizations) -: Urbanization :-Causes of Urbanization Effects of urbanizationAttraction towards fast and glamorous city life.

Sports & recreational facilities develop in cities.

Modern health care facilities are available in cities.

Growth of slump.

Social tension increase, criminal activities breed in towns & cities.

Release of harmful industries causes acid rain.