North-East India is a physically diverse region of India located between the Himalayas and the Indo-Myanmar mountain system. Due to tectonic movements, river action and climatic factors, the region is divided into five major physiographic divisions. These divisions strongly influence the climate, drainage, agriculture, settlement and economic activities of the region.
The North-Eastern Frontier Mountain Ranges, also known as the Arunachal Himalaya, are located in Arunachal Pradesh and form part of the Eastern Himalayas. These mountains are young fold mountains with high elevation and rugged relief. Important hill ranges include the Mishmi, Patkai and Abor hills. Many important rivers, such as the Siang, Subansiri and Lohit, originate from this region, and it acts as a climatic barrier and forest-rich zone.
The Brahmaputra Valley lies between the Arunachal Himalaya in the north and the Meghalaya Plateau in the south. It is a wide alluvial plain formed by sediment deposition from the Brahmaputra River and its tributaries. The valley has fertile soil and supports crops such as rice, tea, and jute. It is densely populated but frequently affected by floods and riverbank erosion.
The Karbi–Meghalaya Plateau is situated south of the Brahmaputra Valley and includes the Karbi Anglong and Meghalaya Plateaus. It is made of old crystalline rocks and is an extension of the Peninsular Plateau. The plateau consists of the Garo, Khasi and Jaintia hills and receives heavy rainfall, especially in areas like Cherrapunji and Mawsynram. This region is important for minerals, forests and horticulture.
The Barak Plain or Cachar Plain is located in southern Assam and is drained by the Barak River. It is a low-lying alluvial plain with fertile soil and supports agriculture, mainly rice and jute. The region is flood-prone but supports dense rural settlements.
The South-Eastern Hill Ranges include Nagaland, Manipur, Mizoram and Tripura and form part of the Indo-Myanmar fold mountain system. These are young fold mountains with steep slopes, narrow valleys and parallel ridges. Important hills include the Naga, Manipur and Mizo (Lushai) hills. Shifting cultivation or jhum is the main agricultural practice in this region.
In conclusion, North-East India has a highly complex and varied physiography consisting of mountains, plateaus and plains. These physiographic divisions play a vital role in shaping the natural environment, human activities and economic development of the region.