Physiography and Drainage

• The slope of the region in the north, shown in dark green, is towards the Aravali ranges and Chhota Nagpur Plateau.
• The peak shown in the Eastern Ghats is Mahabaleshwar.
• The mountains that demarcate the deep plains of Brahmaputra are the Himalayas.
• The region with an altitude of more than 6000m lies in the Ladakh region of India.
• The south-flowing river in the peninsular region is the Cauvery.
• The Nilgiri Hills are located in the south-western part of India.
• The Vindhyas act as a water divide between the Ganga and the Yamuna river basins.
• The range of the altitude of the Amazon river basin is 200 to 1000 metres.
• The Amazon river basin is located between the Andes and the Atlantic Ocean.
• The isolated regions shown in yellow indicate the presence of regions with an altitude of less than 200m.
• The plateau region with a height of 200 to 500 m through which tributaries of Amazon flow is located in the Brazilian state of Mato Grosso.
• The Western Ghats are called a water divide because they act as a barrier to the flow of water from the west to the east.
• India has a long coastline extending for approximately 7500 km, which lies to the western and eastern part of the Peninsula.
• The western coast of India, which borders the Arabian Sea, is a rocky coast with spurs taking off from the Western Ghats extending up to the coast.
• The eastern coast of India, which borders the Bay of Bengal, is a deltaic coast formed as a result of the depositional work of rivers.
• Amazon is a large river in the world, with its mouth located in the deltaic regions.
• There are no west-flowing rivers in Brazil, dissimilarities between the eastern and western coasts of India, fewer natural ports on the eastern coast of India, and as compared to Amazon, pollution in river Ganga will affect human life greatly.
• These rivers of Brazil are north-flowing: Juruika- Xingu- Aragua.
• The Amazon Basin is mainly characterized by droughts, filled by swamps, covered by dense forests, and fertile.
• The order of physiographic units in Brazil while going from North-West to South-East is Parana River basin- Guyana Highlands- Brazilan Highlands.
• The order of plateaus of India from south to north is Karnataka- Maharashtra- Bundelkhand, Chhota Nagpur- Malwa- Marwad, Telangana-Maharashtra-Marwad.
• The Chola king constructed a dam on the river Kaveri in the 2nd century A.D. near Tiruchirapalli and started irrigation in this deltaic region.
• The Lakshadweep Islands of Arabian Sea are made from the part separated from the mainland, coral islands, volcanic islands, and continental islands.
• Brazil and Guyana shields are considered to be the core of the South American continent.
• To the foot hills of the Aravalis lies the Bundelkhand Plateau, Mewad Plateau, Malwa Plateau, and Deccan Plateau.
• The Shield Area is considered to be the core portion of a continent, made up of igneous crystalline rocks and high grade metamorphic rocks, and their period can be from 580 million to 2 billion years.
• India has many small and large islands along the coast of the mainland, which are included in the coastal island group.
• The west flowing rivers occupying the area between the Western Ghats and the Arabian Coastline are short in length but swift.
• Coastal rivers in Brazil are numerous and attain significance due to the dense population in the coastal area.
• Himalayan drainage covers two major river systems such as Indus river system and Ganga river system.
• River Paraniba and River Itapecuru flowing northwards meet the North Atlantic Ocean.
• Rivers in India are largely classified according to their source region into Himalayan and Peninsular rivers.
• The size of catchment area, their relative location within respective countries, headwater regions of rivers, orientation of the rivers, major tributaries and their orientation are factors that can be considered for comparison of the basins of Ganga and Amazon river.
• Brahmaputra, Ganga, Damodar, Mahanadi, Brahmani, Son, Yamuna, Chambal, Narmada, Tapi, Godavari, Manjra, and Bhima are the main rivers and lakes in India.
• Most of the major rivers in the Himalayas originate from various glaciers, flood during monsoons, and are perennial rivers.
• Sao Francisco is the third important river of Brazil, occupying the eastern portion of the highlands and flowing towards the north for a distance of about 1000 km over the plateau before entering the coastal strip along the Atlantic Ocean.
• Major rivers of Brazil and India are shown in figure 3.3 and 3.4.
• Drainage basin maps of Amazon and Ganga can be prepared using two tracing papers.
• The physiography of India and Brazil can be described based on the distribution of altitude, direction of slope of land and other characteristics.
• Paraguay-Parana system consists of two rivers located in the southwestern part of Brazil that form the catchment of River Plata in Argentina.