Assertion ; the deposition of alluvium in vast basin lying in the foot...
The Formation of the Fertile Northern Plain
The assertion states that the deposition of alluvium in a vast basin lying in the foothills of the Himalayas over millions of years formed the fertile northern plain. This is supported by the reason that the northern plain is formed by the interplay of major river systems. Let's delve into the details to understand this process.
The Deposition of Alluvium
Alluvium refers to the loose, unconsolidated soil and sediment that is transported and deposited by rivers. The Himalayas, with their towering peaks, experience heavy rainfall and have numerous rivers flowing through their foothills. These rivers carry a significant amount of sediment eroded from the mountains, including rocks, sand, silt, and clay.
The Vast Basin in the Foothills of the Himalayas
The foothills of the Himalayas form a vast basin that stretches across the northern part of the Indian subcontinent. This basin is formed by the interplay of major river systems that originate in the Himalayas. The rivers, such as the Indus, Ganges, and Brahmaputra, flow through the basin, carrying the sediment eroded from the mountains.
Deposition of Alluvium in the Basin
As the rivers flow through the foothills, their velocity decreases, leading to the deposition of the sediment they carry. This deposition process occurs over millions of years, gradually building up layers of alluvium in the basin. The alluvium is composed of fine particles such as silt and clay, which settle out of the river water as the velocity decreases.
Formation of the Fertile Northern Plain
The continuous deposition of alluvium in the basin has resulted in the formation of the fertile northern plain. The alluvial soil deposited by the rivers is highly fertile and ideal for agriculture. This soil is rich in nutrients and retains moisture, making it suitable for the cultivation of a variety of crops. The fertile northern plain is often referred to as the "breadbasket" of India due to its agricultural productivity.
The Interplay of Major River Systems
The reason provided states that the northern plain is formed by the interplay of major river systems. This refers to the complex interaction between the rivers originating from the Himalayas. The rivers flow through the basin, carving out their paths and depositing alluvium along their course. The interplay of these river systems contributes to the overall shape and formation of the northern plain.
In conclusion, the assertion that the deposition of alluvium in a vast basin lying in the foothills of the Himalayas over millions of years formed the fertile northern plain is supported by the reason that the northern plain is formed by the interplay of major river systems. The continuous deposition of alluvium by the rivers has resulted in the formation of the fertile soil in the northern plain, making it an agriculturally productive region.
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