Human Environment Interactions: The Tropical And The Subtropical Region (Basic)

Life In The Amazon Basin

The Amazon Basin is located around the Equator in the tropical region of South America. It is a vast river basin where the Amazon River flows. This region is characterized by dense rainforests and a significant impact of human activities on its environment.

Climate

The Amazon Basin experiences a hot and humid climate throughout the year. The average temperature is around $30^\circ$C, and there is very little variation in temperature. The region receives heavy rainfall almost every day, usually in the afternoon, which can be very intense. This rainfall contributes to the high humidity levels. The climate can be described as:

Temperature: Consistently high, around $30^\circ$C, with minimal seasonal variation.
Rainfall: Heavy and frequent throughout the year, often occurring as thunderstorms in the afternoon.
Humidity: High due to the constant evaporation from the river and dense vegetation.

Rainforests

The Amazon Basin is home to the world's largest rainforests, known as the Amazon rainforest. These rainforests are incredibly diverse and play a crucial role in regulating the global climate. Key features of the rainforests include:

Dense Vegetation: The forests are so dense that the sunlight struggles to reach the ground. The canopy layer, formed by the tall trees, blocks most of the sunlight.
Layered Structure: The vegetation is organized into several layers: the canopy, the understory, and the forest floor.
Biodiversity: The rainforests support an astonishing variety of plant and animal life. It is estimated to house millions of species of insects, birds, mammals, and plants.
Economic Importance: Many valuable timber species like mahogany, rosewood, and ebony are found here. Various medicinal plants are also present.

People Of The Rainforests

The Amazon Basin is inhabited by indigenous communities who have lived in harmony with the rainforest for centuries. However, there has been increasing pressure from external forces due to the rich natural resources of the region.

Indigenous Communities:

These communities have traditional lifestyles deeply connected to the forest. They rely on hunting, fishing, and gathering forest produce for their sustenance. They practice subsistence farming, growing crops like cassava and maize in small clearings. Their knowledge of the forest, its plants, and animals is extensive and passed down through generations.

Inhabitants and Livelihoods:

The inhabitants of the Amazon Basin engage in various activities:

Agriculture: They practice subsistence agriculture, growing crops like pineapple, papaya, banana, and cassava in small patches cleared from the forest.
Fishing: The Amazon River and its tributaries are rich in fish, which forms a significant part of their diet.
Hunting: They hunt animals like deer, monkeys, and capybaras for food and other resources.
Gathering: They collect fruits, nuts, and medicinal plants from the forest.

Challenges and Development:

In recent times, the Amazon rainforest has faced significant challenges due to deforestation, mining, and agricultural expansion. This has led to:

Loss of Biodiversity: Habitat destruction due to deforestation threatens many species with extinction.
Climate Change: The Amazon rainforest plays a vital role in regulating global climate by absorbing carbon dioxide. Deforestation contributes to climate change.
Impact on Indigenous Peoples: The traditional way of life of indigenous communities is threatened by these developments, leading to social and cultural disruption.
Government Initiatives: Governments are implementing measures to conserve the rainforest, promote sustainable development, and protect the rights of indigenous peoples.

Life In The Ganga-Brahmaputra Basin

The Ganga-Brahmaputra basin is located in the Indian subcontinent, formed by the Ganga and Brahmaputra rivers and their tributaries. This is a densely populated region with a diverse range of geographical features and human activities.

Geography Of The Basin

The Ganga-Brahmaputra basin is a vast river basin situated in India, Nepal, Bhutan, and Bangladesh. The two major rivers, the Ganga and the Brahmaputra, originate in the Himalayas and flow through different terrains before meeting in Bangladesh to form the world's largest delta, the Sundarbans. The basin can be broadly divided into:

The Mountains: The northern part of the basin is covered by the Himalayas, characterized by high altitudes and steep slopes.
The Plains: The middle part consists of the vast, fertile plains formed by the deposition of alluvium by the rivers. This is the most densely populated area.
The Delta: The southern part is the low-lying delta, a region of distributaries, creeks, and swamps.

The soil in the plains is rich alluvial soil, making it highly fertile for agriculture.

Climate

The Ganga-Brahmaputra basin experiences a monsoon climate. The climate is characterized by distinct seasons:

Summer (March to May): Hot and dry, with temperatures rising significantly.
Monsoon Season (June to September): This is the period of heavy rainfall brought by the southwest monsoon winds. The rainfall is crucial for agriculture but can also lead to floods.
Post-Monsoon Season (October to November): Rainfall decreases, and the weather becomes pleasant.
Winter (December to February): Cool and dry, with clear skies and mild temperatures in the plains.

The amount of rainfall varies across the basin, with the northeastern parts receiving exceptionally high rainfall, while the western parts are drier.

Population Distribution

The Ganga-Brahmaputra basin is one of the most densely populated regions in the world. The fertile plains, availability of water, and favorable climate support a large population. Major urban centers like Delhi, Kolkata, and Dhaka are located within this basin.

Factors contributing to high population density include:

Fertile Land: Alluvial soil supports intensive agriculture, providing food for a large population.
Availability of Water: Rivers provide water for irrigation, drinking, and transport.
Economic Opportunities: The presence of industries and cities attracts people for employment.

However, this high population density also leads to challenges like pressure on resources, pollution, and strain on infrastructure.

Agriculture

Agriculture is the primary occupation in the Ganga-Brahmaputra basin due to the fertile alluvial soil and ample water supply. The main crops grown are:

Paddy (Rice): Grown in areas with high rainfall, it is the staple food for millions.
Wheat: Cultivated in the drier parts of the plains, especially in the western regions.
Maize: Grown in various parts of the basin.
Jute: Known as the 'golden fibre', it is grown in the deltaic regions, particularly in West Bengal and Bangladesh.
Sugarcane: Cultivated in the plains.
Tea: Grown in the hilly areas of Assam and West Bengal, with plantations established on slopes.

Terrace farming is practiced in the hilly areas to cultivate crops like tea.

Vegetation and Wildlife

The vegetation of the Ganga-Brahmaputra basin is diverse, reflecting the variations in climate and topography.

Tropical Evergreen Forests: Found in areas with heavy rainfall, characterized by tall trees, dense undergrowth, and a variety of evergreen species.
Deciduous Forests: Trees in these forests shed their leaves during the dry season. Sal and teak are important species.
Mangrove Forests: The Sundarbans delta is famous for its mangrove forests, which are adapted to saline and waterlogged conditions. The Royal Bengal Tiger is the most famous inhabitant of the Sundarbans.
Grasslands: Found in the floodplains and higher altitudes.

Wildlife in the basin includes a wide range of animals such as tigers, elephants, deer, monkeys, various species of birds (parrots, pigeons, mynahs, cranes), snakes, and crocodiles. The diverse habitats support a rich ecosystem.

Towns, Cities and Pollution

The Ganga-Brahmaputra basin is home to some of the largest and oldest cities in India, Bangladesh, and Nepal. These include Delhi, Kolkata, Patna, Lucknow, Kanpur, Varanasi, Dhaka, and Guwahati. These cities serve as administrative, industrial, and cultural centers.

Pollution is a significant issue in this basin, particularly in urban areas:

Water Pollution: Rivers like the Ganga are heavily polluted due to untreated sewage, industrial waste, and agricultural runoff. This poses a serious threat to aquatic life and human health.
Air Pollution: Industrial emissions, vehicle exhaust, and burning of fossil fuels contribute to poor air quality in cities.
Noise Pollution: High population density and traffic also contribute to noise pollution.

Efforts are being made through various government initiatives like the 'Namami Gange' program to clean up the rivers and improve environmental conditions.

Transport

The Ganga-Brahmaputra basin has a well-developed transport network:

Roadways: An extensive network of roads connects villages, towns, and cities.
Railways: The Indian Railways network is one of the largest in the world and plays a vital role in transporting goods and passengers across the basin.
Waterways: The Ganga and Brahmaputra rivers are important natural waterways. They are used for transporting goods and people, especially in the deltaic regions and for tourism. The Ganga river has been declared a National Waterway.
Airways: Major cities have airports, facilitating air travel.

Tourism

The Ganga-Brahmaputra basin offers a rich variety of tourist attractions, catering to different interests:

Religious and Spiritual Sites: Cities like Varanasi, Haridwar, Rishikesh, and Bodh Gaya are major pilgrimage centers.
Historical Monuments: Numerous forts, palaces, and historical structures dot the landscape.
Natural Beauty: The Himalayas offer trekking and adventure tourism. The Sundarbans provide opportunities for wildlife viewing, especially the Royal Bengal Tiger. Tea gardens in Darjeeling and Assam are also popular attractions.
River Cruises: Cruises on the Ganga and Brahmaputra rivers offer a unique way to experience the region's culture and scenery.