Streams do a large of geological work. Flowing water from upstream toward downstream possesses a tremendous amount of energy. The geological work of streams is to erode the valley, transport the eroded material, and deposit the same in the lower reaches at favorable sites. Stream Erosion: The stream causes erosion in four ways: (i) chemical
What is a Wind? The air currents in the motion are called “wind”. The wind is an important agent of erosion, transportation and deposition. Its work is particularly seen in arid regions. Wind Erosion: Although wind erosion is not restricted to arid and semi-arid regions, it does its most effective work in these areas. Wind
Historical background The phenomenon of migration or human mobility has been going on since ancient times. This process began about a million years ago when Homo Erectus reached Eurasia from Africa. Then a second wave left the shores of dark continent (Africa)about 70,000 years and migrated Asia, Europe and Australia. It is believed that Americas
Arid Zone: In arid regions where days are very hot and nights are cool, the rocks shatter mainly by the influence of unequal expansions and contraction. The soil thus produced contains the grain of minerals which are disintegrated from the original rock. The surface layers of such soil often become hard due to the crystallization
Regolith: Regolith is any solid but unconsolidated material laying on the top surface of the bedrock. Regolith includes soil, alluvium, and rock fragments weathered from the bedrock. The thickness of this mantle varies from nil over rock exposures to very deep in areas protected from erosion. Soil: Soil is the top layer of the regolith.
The trend of population ageing is presently on the increase because the people are living longer now due to better food and healthcare. The falling fertility rate is reducing the proportion of younger people. Thus most of the countries are now facing the challenge of greying population. According to UN figures, over the past half
The term structure of population means age wise and sex-wise composition of the population along with the description of qualitative characteristics. Age Structure of Population: Age structure is an important characteristic of the population of a country or a region. The population is generally composed of different age group which greatly influence the social attitudes,
Australia and Oceania include the mainland of Australia, New Zealand and the islands located in the South Pacific. Countries of Australia and Oceania: This region comprises of the following countries: Australia, Papua New Guinea, New Zealand, Nauru, Marshal Islands, Kiribati, Fiji and Palau. Country Area (Sq.Km) Population (2020) Capital Australia 2967909 25,499,884 Canberra New Zealand
Continent of Latin America/South America is the fourth largest landmass in the world. It covers an area of 17819000 sq.km and has a population of million. Latin America comprises of 18 nations viz. Argentina, Brazil, Peru, French, Guiana, Suriname, Venezuela, Colombia, Chile, Ecuador, Bolivia, Paraguay, Uruguay, Guyana, Trinidad & Tobago, St. Kitts, St. Vincent and
North America is the third largest continent of the world with an area of 24.71 million sq.km which is 16.5 of the total area of the world. It is bounded by Arctic in the North, South America in the south, Pacific Ocean in the west and Atlantic Ocean in the east. Major portion of this
