Coastal Plains (  Important for UPSC)

India boasts a diverse and extensive coastline spanning approximately 7,516.6 kilometers, encompassing not only the mainland but also the enchanting Andaman and Nicobar Islands and the picturesque Lakshadweep Islands. This coastal stretch gracefully embraces and influences the geography and culture of 13 states and Union Territories.

On the western front, India’s coastline unfolds with the Western Coastal Plains, hugging the glistening waters of the Arabian Sea. This stretch of land is renowned for its lush green landscapes, sandy beaches, and a rich tapestry of coastal communities.

On the eastern flank, India’s coastline extends along the Bay of Bengal, bestowing its natural beauty upon the Eastern Coastal Plains. Here, the landscape is characterized by fertile deltas, mangrove forests, and a unique blend of coastal traditions.

Overall, India’s coastline is not merely a geographical feature but a vital aspect of its identity, offering a diverse range of ecosystems, livelihoods, and cultural richness that contribute significantly to the nation’s heritage and biodiversity.

About coastal plains of India

Coastal plains in India refer to expansive, low-lying regions adjacent to the seashore, characterized by their flat and gentle terrain. These coastal plains are unique geographical features, bounded on one side by the vast expanse of the sea or ocean and on the other by towering mountain ranges. 

This geographical arrangement confines these plains to a narrow strip, with the coastline serving as their natural boundary on one side, and the elevated highlands acting as their landward limit. 

As one journeys from the coastline towards the inland highlands, the elevation gradually increases, forming a succession of flat terraces interspersed with minor hills or undulating terrain, typically ranging in altitude from 100 meters to 300 meters.

India’s coastal regions encompass a vast area of 7,516.6 kilometers, comprising a mainland coastline stretching across 6,100 kilometers and an additional shoreline extending to 1,197 Indian islands. This expansive coastal belt touches upon the territories of 13 states and Union Territories.

These coastal lowlands in India can be broadly categorized into two distinct types:

• Eastern Coastal Plains: These plains run along the eastern seaboard, adjacent to the Bay of Bengal. They are known for their fertile delta regions, mangrove ecosystems, and cultural diversity.

• Western Coastal Plains: Situated along the Arabian Sea on the western side of India, these plains feature picturesque landscapes, sandy beaches, and thriving coastal communities.

Overall, India’s coastal plains are not only critical from a geographical standpoint but also hold immense ecological and cultural significance, contributing to the nation’s diversity and natural heritage.

READ MORE
POLITY: Pressure Groups, PIL ( Important Topics For APSC): Coastal Plains (  Important for UPSC)

Formation of India’s Coastal Plains

Millions of years ago, the Indian subcontinent played a significant role as part of the ancient Gondwanaland supercontinent. Around 140 million years ago, a pivotal chapter in Earth’s geological history unfolded. The process of continental drift initiated, causing the Indian landmass to embark on a remarkable journey.

As the continental drift separated the Indian subcontinent from Gondwanaland, it began its solitary odyssey, eventually colliding with the massive landmass of Asia. This collision marked a pivotal moment in the shaping of India’s geological landscape. The Indian subcontinent found its permanent abode, nestled against the Eurasian plate.

During this extended geological saga, the continental migration of the Indian subcontinent had far-reaching consequences. The immense tectonic forces at play led to the creation of two significant water bodies that now flank India on its west and east sides: the Arabian Sea and the Bay of Bengal, respectively.

This tectonic migration and the subsequent separation from Gondwanaland left an indelible mark on the Indian subcontinent. The result was the formation of the coastal plains that grace India’s extensive shoreline. These coastal plains, characterized by their uniform and mostly linear appearance, bear testimony to the ancient geological processes that unfolded during the Cretaceous period.

In essence, India’s coastal plains are a testament to the geological history of the Indian subcontinent, shaped by the forces of tectonic movement, continental drift, and the gradual formation of two vast oceanic expanses on either side. This remarkable journey through time and geology has endowed India with its distinctive and picturesque coastal regions, rich in both natural beauty and historical significance.

Significance of India’s Coastal Plains:

• The vast expanses of India’s coastal plains are blessed with fertile soils, facilitating the cultivation of a wide variety of crops. Among these, rice stands out as the primary crop grown in these regions.
•  Along the entire coastline, coconut trees thrive, forming lush groves that contribute significantly to the agricultural landscape.
• The extensive coastline is studded with both major and minor ports, serving as crucial nodes for trade and commerce, facilitating the movement of goods both domestically and internationally.
•  These plains are known to harbor substantial deposits of mineral oil, notably in the KG Basin, making them a valuable resource for energy production.
• The sands along the Kerala coast contain substantial quantities of Monazite, a mineral essential for nuclear power generation.
• Coastal regions are home to vibrant fishing communities, where fishing serves as a prominent occupation, ensuring a sustainable livelihood for the local populace.
•  The low-lying areas of Gujarat are renowned for their salt production, contributing significantly to the country’s salt supply.
• India’s coastal regions offer an array of tourist destinations, including the famous Kerala backwaters, known for their serene beauty and unique ecosystem. Goa, with its pristine beaches, is also a prominent tourist hotspot, attracting visitors from around the world.

The Eastern Coastal Plains of India

Stretching from the northern state of West Bengal to the southern tip of Tamil Nadu, the Eastern Coastal Plains form a dynamic and geographically diverse region. Along this extensive coastal stretch, which traverses the states of Andhra Pradesh and Odisha, several notable features and ecosystems thrive.

Delta Regions

 One of the defining characteristics of the Eastern Coastal Plains is the presence of extensive delta regions. These deltas are formed by the mighty rivers of the region, including the Mahanadi, Krishna, Godavari, and Cauvery. These river deltas are exceptionally fertile and productive, making them crucial hubs for agriculture. Among them, the Krishna River delta has earned the moniker “Granary of South India” due to its exceptional agricultural output.

Segmented Coastline

 The Eastern Coast can be segmented into three distinct sections:

   Utkal Coast

Stretching between Chilika Lake and Kolleru Lake, the Utkal coast is notably broader than its western counterpart. This region receives substantial rainfall and is characterized by lush vegetation. Here, crops like rice, coconut, and banana flourish. The picturesque Chilika Lake stands out as a prominent physiographic feature in this area.

  Andhra Coast

Extending from Kolleru Lake to Pulicat Lake, the Andhra coast serves as a basin for the Krishna and Godavari rivers. It runs south of the Utkal Plain and features Sriharikota Island, a lengthy sand spit that has effectively sealed off access to Pulicat Lake. However, this region lacks well-developed harbors, with only Visakhapatnam and Machilipatnam serving as exceptions along its relatively straight shoreline.

 Coromandel Coast

Stretching from Pulicat Lake down to Kanyakumari in Tamil Nadu, the Coromandel coast experiences a unique climatic pattern. It remains dry during the summer and receives rainfall primarily during the winter months, owing to the influence of the northeast monsoons. The standout feature of this region is the expansive Cauvery delta, spanning 130 kilometers in width. Renowned for its fertile land and extensive irrigation systems, the Cauvery delta has earned its reputation as the “Granary of South India.”

The Eastern Coastal Plains, with their rich agricultural output, diverse ecosystems, and unique climatic patterns, play a pivotal role in the cultural, economic, and ecological fabric of the region. They are not only a testament to India’s geographical diversity but also a vital resource for the nation’s agricultural and economic prosperity.

The India’s Western Coastal Plains

Extending from the picturesque state of Kerala in the south to the vibrant Gujarat in the north, the Western Coastal Plains offer a captivating tapestry of landscapes, cultures, and natural riches. Spanning approximately 1500 kilometers from north to south, these coastal plains exhibit widths ranging from 10 to 25 kilometers, creating a dynamic and geographically diverse region.

West Continental Shelf

The Western Coastal Plains are at their widest near the Bombay coast, forming the West Continental Shelf. This region holds significant reserves of oil, contributing to India’s energy resources.

Lagoon Enchantment

Along the Malabar Coast, these plains are adorned with enchanting lagoons, making it a sought-after tourist destination. These serene lagoons add to the region’s natural allure and are a testament to its diverse ecosystems.

The Western Coastal Plains can be classified into four distinctive sections:

1.Kachchh and Kathiawar Coast

Shaped by the deposition of silt from the Indus River, these coasts have unique topographies. During the monsoon season, Kachchh experiences shallow inundation, creating the Great Rann in the north and the Little Rann in the east. The filling of seas and lagoons by materials carried by the Indus River has transformed the Kutch Peninsula from an island into a semi-arid landscape. Kathiawar, to the south of Kachchh, offers a different terrain.

2.Konkan Coast

Stretching from Daman in the north to the charming beaches of Goa in the south, the Konkan coast is marked by the cultivation of rice and cashew, two of its prominent crops.

3.Kanada Coast

This coastal region, spanning from Madgaon to Mangalore, is rich in iron resources. Here, the plains are relatively narrow, with an average width of 30-50 kilometers, reaching a maximum of 70 kilometers near Mangalore. The region is characterized by the steep hills of the Western Ghats, giving rise to numerous streams and waterfalls.

 4.Malabar Coast

Extending from Mangalore down to the southern tip of Kanyakumari, the Malabar coast boasts an expansive stretch. Notably, this region encompasses lagoons running parallel to the shore, a distinctive geographical feature. These lagoons, locally known as ‘Kayals,’ serve various purposes, including fishing, interior navigation, and tourism.

The Western Coastal Plains, with their rich geological diversity, unique ecosystems, and cultural vibrancy, are an integral part of India’s coastal heritage. They offer not only picturesque landscapes and tourist attractions but also valuable resources that contribute to the nation’s economic and ecological well-being.

Coastlines in Transition: Emergence and Submergence Dynamics

India’s coastal regions are dynamic landscapes where nature’s forces have played a significant role in shaping the boundaries between land and sea. These coastlines can be categorized into two fascinating and contrasting types: emergent and submergent coastlines, each offering a unique blend of geological features and ecological characteristics.

Emergent Coastlines

Emergent coastlines come into existence when sea levels drop or the land undergoes uplifting processes. This uplifting action can be attributed to tectonic forces, gradually revealing coastal structures and formations. The south-eastern half of India, particularly the Tamil Nadu coast, exemplifies the emergent coastline phenomenon. Key characteristics of emergent coastlines include:

1. Formation Mechanism: Emergent coastlines owe their existence to either a decrease in sea level or an uplift of the landmass.
2. Distinctive Features:As these coastlines emerge, they unveil various landforms such as bars, lagoons, beaches, arches, sea cliffs, salt marshes, and spits. Additionally, elevated marine terraces may form over time.

Examples: The Coromandel coast in Tamil Nadu and the Malabar Coast in Kerala exemplify emergent coastlines in India.

Submergent Coastlines

In contrast to emergent coastlines, submergent coastlines are shaped by rising sea levels or land subsidence. Along India’s west coast, a complex interplay of both emergence and submergence is observed. Submergent coastlines are characterized by:

1. Formation Mechanism:

These coastlines come into being when sea levels rise, or the landmass experiences subsidence, causing previously visible land features to become submerged.

2. Distinctive Features:

Submergent coastlines often exhibit estuaries, barrier bars, and barrier island systems. Ridges separate valleys that extend into the sea, creating unique topographies.

Example: The Konkan coast, spanning Maharashtra and Goa, serves as a compelling illustration of a submerged shoreline in India.

India’s coastlines, whether emergent or submergent, narrate tales of geological processes, environmental adaptation, and human interaction. They provide valuable insights into the dynamic relationship between land and sea, offering a glimpse into the ever-evolving nature of our planet’s coastal regions.