Drainage System

In geomorphology, the drainage systems, which are also known as a stream or river systems, are the patterns formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks and the gradient of the land. Geomorphologists and hydrologists often view …

Base Level and Graded Stream

Longitudinal Profile: Plot of the relative elevation of a stream bed from headwaters to mouth is called its “longitudinal profile”. The longitudinal profile of the stream is generally concave upward which is in accordance with the steady downstream decrease in slope. Base Level: The level which controls the depth of stream erosion is called a …

Depositional Landforms

A stream erodes a large amount of sediments and debris of the rocks and earth surface. The separation of sediments from the surface is called Weathering. The movement of these sediments from their origin to low lying areas is called erosion. Both the processes of weathering and erosion are collectively called Denudation. As a result …

Features of Stream Erosion

Stream erosion brings enormous changes within the landscape of its passage. The power of water gets succeeded in order to remove all kinds of obstacles before its way. It cuts the rocks, erodes the ledges, digs out trenches. Stream water brings many changes to the channel it passes through. Following are the main features of …

Work of Streams

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 …

Work of Wind

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 …

Human Migration

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 …

Climate and Soil formation

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 …

Soil and its types

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. …

Population ageing in the world

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 …