Geography & Environment & Disaster management

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FRA Cells to speed up Forest Rights Implementation

Context: The Central government has sanctioned over 300 FRA Cells to facilitate the implementation of the Forest Rights Act, 2006 across 18 states and UTs. 

Relevance of the Topic: Prelims: Key Features of FRA Cells, FRA 2006, DAJGUA.

Pending Forest Rights Claims

  • According to the March 2025 progress report, about 14.45% of the 51.11 lakh forest rights claims filed under the Forest Rights Act (FRA), 2006 across 21 States/UTs still remain pending. 
  • Even among the 43 lakh disposed claims, over 42% have been rejected indicating serious issues in the implementation process.

To address these long-standing delays and rejections, the Union government has sanctioned over 300 FRA Cells across 18 states & UTs. 

About Forest Right Act 2006

  • Also known as Schedule Tribes and Other Traditional Forest Dwellers Act.
  • The act recognises and vests the forest rights and occupation in Forest land in Forest Dwelling Scheduled Tribes (FDST) and Other Traditional Forest Dwellers (OTFD) who have been residing in such forests for generations.

The Act identifies Four Types of Rights: 

  • Title rights: Gives FDST and OTFD, the right to ownership of land farmed by tribals or forest dwellers subject to a maximum of 4 hectares. Ownership is only for land that is being cultivated by the concerned family and no new lands will be granted. It also provides for Community rights over minor forest produce and other resources.
  • Use rights: The rights of the dwellers extend to extracting Minor Forest Produce, grazing areas, pastoralist routes, etc.
  • Relief and development rights: To rehabilitation in case of illegal eviction or forced displacement and to basic amenities, subject to restrictions for forest protection.
  • Forest management rights: It includes the right to protect, regenerate or conserve or manage any community forest resource  which they have been traditionally protecting and conserving for sustainable use.

Key Facts: 

  • The Act recognises both individuals and community rights. 
  • The decision and declaration of Habitat rights under FRA is in the jurisdiction of the Ministry of Tribal Affairs.
  • The claim needs to be approved by the Gram Sabha. The decision of the Gram Sabha to reject or allow the claim can be appealed before court.

About FRA Cells

  • FRA Cells are created in districts and states to assist in implementing the Forest Rights Act, 2006, law meant to give forest rights to Scheduled Tribes and forest-dwelling communities.
  • This is being done under a new scheme called Dharti Aba Janjati Gram Utkarsh Abhiyaan (DAJGUA ). 

Key details about FRA Cells: 

  • Until now, implementation of the FRA, has been the domain of State and Union Territory governments who were supposed to form local committees like Gram Sabhas, Sub-Divisional Level Committees (SDLCs), District Level Committees (DLCs), etc., to process land claims.
  • Now, under DAJGUA, 324 district-level FRA cells and 17 state-level FRA cells have been approved. The rules governing the operation of these cells flow from the DAJGUA programme and not the principal legislation of the FRA. 
  • FRA Cells are meant to help tribal people and Gram Sabhas prepare documents, manage data, and push pending claims, not to interfere in decision-making. 
  • The highest number of district FRA cells are sanctioned in Madhya Pradesh (55), followed by Chhattisgarh (30), Telangana, Maharashtra, Assam, and Jharkhand. 
  • Though FRA cells function under state machinery as per DAJGUA rules, they are centrally funded through Grants-in-Aid General, as seen in sanction orders for states like Assam, Himachal Pradesh, and Odisha. The guidelines provide a budget of ₹8.67 lakh for each FRA cell at the district level, and ₹25.85 lakh for each State-level FRA cell.

Dharti Aba Janjati Gram Utkarsh Abhiyaan (DAJGUA): 

  • A central sector scheme launched in October 2024. 
  • Purpose: To Improve tribal welfare across 68,000 tribal-dominated villages by bringing together 25 interventions of 17 line ministries. 
  • One component of the DAJGUA programme is to speed up FRA implementation.

Concerns: Forest rights activists and experts have raised concerns of FRA Cells being a parallel FRA mechanism outside of FRA’s purview and that it could weaken community control.

Hydrology of Brahmaputra

Context: The Chief Minister of Assam addressed concerns surrounding the Brahmaputra River, emphasising that 65-70% of the Brahmaputra’s flow is generated within India, reassuring the public about India’s water sovereignty.

Relevance of the Topic: Prelims: Key facts about Brahmaputra River System; Key Hydropower Projects. 

Hydrology of Brahmaputra River

  • Brahmaputra originates as Yarlung Tsangpo in Kailash range near Mansarovar lake in Tibet. It traverses more than 1,000 km eastward, before forming a horseshoe bend around the Namcha Barwa peak, and enters near Gelling in Arunachal Pradesh as the Siang (or Dihang). 
  • Brahmaputra is primarily a rain-fed river system, with only approximately 30-35% of its flow coming from China, mostly through glacial melt and scanty rainfall that happens in the Tibetan region. 
  • The majority of the river’s water (about 65-70%) arises within India itself due to the monsoon rains that pour over the Northeast’s hilly terrains and the numerous tributaries feeding the river.
  • The river is called Siang in Arunachal, is joined by many tributaries in Assam as it flows down the plains before entering Bangladesh, where it is called Jamuna. 
Left/ South bank Tributaries of BrahmaputraRight/ North bank Tributaries of Brahmaputra
DihangKameng
DibangManas
LohitSubansari
Noa DehingDhansiri (North)
Burhi Dehing Sankosh
KopilliRonganadi
Dhansiri (South)
Kolong
image 18

Hydro-statistics and Regional data

  • Brahmaputra’s flow at key points exemplifies India’s water independence. At the Indo-China border, near the Tuting region in Arunachal Pradesh, the flow rate is around 2,000-3,000 cubic metres per second. 
  • During the monsoon season, as the river enters Assam’s plains, the flow swells to an impressive 15,000-20,000 cubic metres per second. 
  • These figures underscore that the river’s strength and volume are predominantly sustained within India’s climatic and geographical domain. Thus, India does not depend on upstream water flow from China to sustain its water needs.

As the region faces severe flooding due to monsoons, India must emphasise resilience and infrastructure over fears of upstream interference. 

Impact of Hypothetical reduction of water by China

  • Even a hypothetical reduction in Chinese water contribution would have a minimal impact on India’s water security or be potentially beneficial. Reduced flow could mitigate the devastating floods that annually ravage Assam and the northeastern region. 

This point also highlights that India’s water system is resilient and primarily driven by monsoon rains and local tributaries.

China’s planned interventions on Brahmaputra

Most of the Chinese infrastructure interventions are hydropower projects with minimal storage, and are located far upstream of Arunachal Pradesh, with no significant impact in Arunachal or Assam.

  • Medog (or Motuo) Hydropower Project: A major concern is the planned massive dam in Medog County near the ‘Great Bend’ where the river makes a U-turn and plunges into a canyon before entering Arunachal Pradesh. The planned 60,000-MW Medog project will be the world’s largest hydropower facility, with a generation capacity three times that of the Three Gorges Dam on the Yangtze, currently the world’s largest hydropower station.
  • South-North Water Diversion (SNWD) project: Concerns have also been raised over China’s massive, multi-decade South-North Water Diversion (SNWD) project, the Western Route of which apparently involves diverting water from the Yarlung Tsangpo (and other rivers) to the country’s dry northern regions.

As a mitigation strategy, India could plan storage on rivers of the Brahmaputra system to absorb the variations in flows (periods of flooding and reduced flows). E.g., The Upper Siang Project will not only generate power, its storage can also serve as a buffer against variations in flows.

India’s interventions to utilise water potential of Brahmaputra:

Brahmaputra and its tributaries carry more than 30% of India’s total water resources potential, and 41% of the total hydropower potential, as per estimates in the CWC-ISRO Brahmaputra Basin Atlas.

  • The National Water Development Authorityhas proposed two links to connect the Brahmaputra and its tributaries to the Ganga basin with the aim of transferring surplus water to water-scarce regions. These are:
    • Manas-Sankosh-Teesta-Ganga Link, joining the Manas, a tributary of the Brahmaputra, to the Ganga via the Sankosh and Teesta
    • Jogighopa-Teesta-Farakka Link, joining the Brahmaputra at the planned Jogighopa Barrage to the Ganga at the Farakka Barrage.
  • However, utilisation of hydropower in Arunachal Pradesh has been slow due to difficulties of land acquisition and concern over the submergence of forest lands, etc.

Environmental Risks: 

  • Risks of flooding may arise from intentional or unintentional operation of reservoirs in Tibet, as well as unforeseen events such as dam failure, landslides, or earthquakes. 
  • Upstream interventions have the potential to affect the river morphology, with consequences for riverine flora and fauna.

Key Facts:

  • Tibetan Plateau is a region of scant rainfall of the order of 300 mm annually. 
  • The southern part of the Brahmaputra river basin in India receives 2,371 mm of rain on average every year, and very few places receive less than 1,200 mm.

India should work to actively seek detailed hydrological and project-related data to continuously assess the downstream impact of Chinese infrastructure interventions and develop comprehensive data sharing protocols with China for advance warning and disaster preparedness.

Why is the health of Tiger dependent on its prey?

Context: The population of species like spotted deer, sambar, and gaur, which are the prey base for Tigers, are declining in certain states like Odisha, Jharkhand, and Chhattisgarh. This decline in their population is a matter of concern for tigers and for wildlife conservation as a whole.

Relevance of the topic:

Prelims: Key facts about Tiger.

Mains: Conservation of keystone species: Significance and challenges. 

Recent assessment report by NTCA: Key Issues:

The National Tiger Conservation Authority and the Wildlife Institute of India has recently prepared the assessment report, which shows: 

  • Declining prey base: For the first time, a detailed assessment of the status of ungulates (hoofed mammals), including deer, pigs, antelopes, and bison, has estimated their abundance across India. However, their populations are declining in east-central India in Odisha, Jharkhand, and Chhattisgarh. 
  • Uneven distribution of prey-base: The core tiger prey species are abundant, especially within tiger reserves and national parks, but not so much in sanctuaries that receive a comparatively lower level of protection, and even less in forest divisions.
  • Habitat fragmentation & inbreeding: Small and isolated populations of species such as barasingha, wild buffalo, pygmy hog, and hog deer, specially in Himalayan states, poses bottlenecks in their genetic diversity as habitat fragmentation prevents the intermixing of different animals.
  • Decline in species due to habitat destruction: Species with narrow ecological preferences like, populations of hog deer which live in grasslands and floodplains, have significantly declined due to the destruction and fragmentation of their preferred wetlands and swamp habitats. Their current distribution is confined to isolated patches in Terai grasslands and floodplains of Ganga and Brahmaputra. 

The signs of prey decline and low density of ungulates are due to severe habitat degradation, infrastructure development projects and mining that fragments forests, left-wing extremism (central India), and subsistence hunting by residents.

Consequences of the fall in population of Ungulates:

  • Impacts health of Tigers: Ungulates form the core prey base of tigers and other large predators. The lack of prey base is a double whammy for tigers, impacting the existing tiger occupancy and forcing them to kill livestock and smaller species.
  • Disrupts ecological balance: The animals help regulate forests and soil health with their feeding habits. A fall in their numbers affects the ecological balance of forests both inside and outside tiger reserves.
  • Increase in Man-Wildlife conflict: Due to the fallout of the prey base, tigers move beyond the reserves to hunt livestock, putting them in closer contact with humans, who kill tigers in retaliation for livestock depredation. 

The report prescribes augmenting prey populations through on-site breeding in enclosures to protect them from predators.

Also Read: Translocation of African Cheetahs: Neither Ecologically Sustainable nor Ethical 

Key Facts about Tiger

  • Tiger is an umbrella species. Its conservation automatically ensures the conversation of a large number of flora and fauna and entire ecosystems.
  • India is home to 75% of the global tiger population. 
    • The National Tiger Conservation Authority (NTCA) conducts a tiger census across India every 4 years.
    • As per the latest Tiger Census Report (2022), India has 3682 tigers. (2967 in 2018)
    • Madhya Pradesh has the highest number of tigers (785) in India, followed by Karnataka (563) and Uttarakhand (560). 
  • Conservation status: 
    • IUCN Red List: Endangered
    • Wildlife Protection Act: Schedule 1
    • CITES: Appendix 1

Read More: List of Tiger Reserves in India 

Air Pollution can increase the risk of Premature Birth

Context: A study by the US researchers finds first molecular level evidence of how exposure to PM2.5 pollutants by pregnant women could lead to higher risk of premature deliveries.

Relevance of the Topic: Prelims: Health implications of Pollution. 

Link between Air Pollution and Premature Birth: 

  • Exposure to pollutants like fine particulate matter, nitrogen dioxide, and sulfur dioxide during pregnancy can lead to an increased risk of complications such as preterm birth, low birth weight, and developmental issues.
  • A recent study has identified that two biological molecules- 'cortexolone' and 'lysoPE(20:3)', show altered levels in women exposed to air pollution.
    • Cortexolone is a glucocorticoid crucial to regulating metabolism, inflammation, and the immune response.
    • lysoPE(20:3) is a lipid present in cells and important for cell function. 
  • Deregulation of these molecules cause disruptions in protein digestion and absorption which are crucial to foetal development.  

Previous studies have shown that these pollutants can penetrate the placental barrier, potentially affecting fetal growth and development.  

Also Read: Air Pollution in India: Major Pollutants

Stratospheric Aerosol Injection

Context: A recent study presents a novel approach to Stratospheric Aerosol Injection (SAI) as a potential means to directly cool the Earth.

Relevance of the Topic: Prelims: Concept and Mechanism of Stratospheric Aerosol Injection Method.

What is Stratospheric Aerosol Injection (SAI)?

  • SAI is a proposed method of cooling the planet and reducing the impacts of climate change by adding a layer of tiny reflective particles (aerosols) to the high atmosphere. 
  • Aerosols reflect sunlight back into space, increasing Earth’s albedo and lowering surface temperatures by reducing the amount of sunlight reaching the earth.
  • The method was inspired by volcanic eruptions, which have been known to have a cooling effect on the planet by spewing aerosols into the air.
  • How well SAI works depends on the type of material injected, the timing of the injection, and the location. 

Key Findings: 

  • Injecting 12 million tonnes of sulphur dioxide every year at an altitude of 13 km in the local spring and summer seasons of each hemisphere could cool the planet by approximately 0.6 degrees Celsius. 
  • To achieve 1°C cooling, 21 million tonnes/year of sulphur dioxide would be required.
  • If the particles were injected at an even higher altitude in the subtropics, only 7.6 million tonnes would be required annually.
  • Higher altitude injection is more effective because particles stay for longer. At lower altitudes particles are more likely to be caught in clouds and washed out by rain. Despite this, researchers are exploring low-altitude spraying because it is technically less challenging.

While there are some benefits to this method, using three times the usual amount of aerosols carries greater risk.

Risks and Side effects of SAI 

  • Social and geopolitical risks: If one country injects aerosols into the stratosphere, all countries will be affected, it could affect global climate patterns, leading to conflicts.
  • Delayed recovery of the ozone hole and increased risk of acid rain.
  • Cooling could mask warming on the ground and make countries complacent about curtailing emissions.

Chenab Bridge - World’s Highest Railway Arch Bridge

Context: Successful completion and inauguration of Chenab Bridge, world’s highest railway arch bridge. 

Relevance of the Topic: Prelims: Key facts related to Chenab Bridge.

About Chenab Bridge

image 12
  • Location: Reasi district of Jammu and Kashmir
  • Total length: 1315 metres (1.3 kms) with a 467-metre-long arch.
  • The world’s highest railway arch bridge stands 359 metres above the Chenab River and is 35 metres taller than the Eiffel Tower.
  • It is a vital link in the ambitious 272 km Udhampur - Srinagar - Baramulla Rail Link railway project, which aims to connect J&K with the rest of the country by rail.
  • Built by: Indian Railways at a cost of ₹1400 crore. The construction was done by a joint venture between Afcons Infrastructure, South Korea’s Ultra Construction & Engineering Company and VSL India, and the arch was designed by Germany-based Leonhardt Andra and Partners.
  • The bridge has a lifespan of 120 years and is designed to handle trains running at 100 km per hour.
  • Chenab Bridge was approved in 2003, it took 22 years to complete the construction, due to the tough and challenging terrain, topographical constraints and political climate. 

Significance of Chenab Bridge: 

Strategic Importance for National Security: 

  • Critical from the national security perspective as it will help in transporting security personnel and material to the border areas during times of conflict. 

Economic Significance: 

Chenab Bridge is expected to give a huge boost to the economy of J&K.

  • By integrating this region through rail with the rest of the country, it will enable movement of goods by rail and more business opportunities.  
  • Easier market access to local businesses, especially to markets in central and southern India. It will particularly benefit the horticulture industry of J&K, especially apple growers who earlier had to rely on road transport to send their produce out of J&K. 
  • Boost to the tourist industry with greater inflow of tourists from other parts of India.
  • Freight traffic through rail is also expected to increase, improving logistics and trade in the region.

Flue Gas Desulphurisation

Context: A high-powered committee of experts, led by Principal Scientific Advisor (PSA) has recommended that India should scrap its policy of mandating coal-fired thermal power plants (TPPs) to install Flue Gas Desulphurisation (FGD) units. FGD units are fitted in TPPs to cut harmful sulphur dioxide (SO2) emissions. 

92% of India’s 600 TPPs have not yet installed FGD units. Instead, the committee recommends limiting FGD unit requirement to plants that use imported or high-sulphur (>0.5%) coal, as these contribute more significantly to SO₂ pollution.

Instead, the study recommends limiting this requirement to plants using imported or high-sulphur (>0.5%) coal, as these contribute more significantly to SO₂ pollution.

Relevance of the Topic:  Prelims: Key facts related to Desulphurisation.  

Rationale behind the Suggestions

  • The rationale underlying the analysis is that 92% of the coal used in Indian plants has low sulphur content (0.3%-0.5%).
    • SO2 levels in ambient air across the country are around 10-20 micrograms/cubic metre, well below India’s air quality norms of 80 micrograms/cubic metre. 
    • SO2 levels in cities near plants with operational FGD units do not differ significantly from those without these units.
    • Particulate Matter samples in urban areas show low levels of elemental sulphur (max 8 micrograms/cubic metre) which is not a significant concern. Thus, FGD units may offer limited benefits in reducing PM pollution. 
  • Norms mandated by the Central Pollution Control Board that require stack heights (exhaust columns) in the thermal power plants be a minimum 220 metres, coupled with Indian climatic conditions, ensure that SO2 emissions do not threaten local air quality.
  • A study by IIT-Delhi in 2024 found that acid rain, the most visible consequence of high SO2 emissions, was not a significant issue in India.
  • Installing FGD in all coal plants would increase power consumption as well as freshwater consumption in the plants, resulting in an additional 69 million tonnes of CO2 (2025-30), while reducing SO2 emissions by 17 million tonnes.
  • Unintended benefit of Sulphate Aerosols: When SO₂ is released into the atmosphere, it reacts with water vapour and other compounds to form sulphate aerosols. These aerosols reflect incoming solar radiation (shortwave radiation) back into space, which results in radiative cooling of the Earth's surface. This cooling effect masks or offsets part of the warming caused by greenhouse gases. 

Flue Gas Desulphurisation

  • Flue Gas Desulphurisation (FGD) is a clean technology system that separates the sulphur dioxide from the exhaust flue gas of coal-fired thermal power plants. 
  • FGD systems utilise various methods, including wet scrubbing with limestone slurry or dry scrubbing with a dry sorbent, to absorb SO2 from the flue gas. 
image 59

How FGD Works?

  • Flue Gas Collection: Flue gas, containing SO2 and other pollutants, is collected from the power plant's boiler or other combustion sources. 
  • SO2 Removal: The collected flue gas is then passed through an FGD system.
    • In wet scrubbing, the gas is sprayed with a limestone slurry. The SO2 reacts with the limestone, forming a calcium sulfite or sulfate, which can be removed as a by-product or waste. 
    • In dry scrubbing, a dry sorbent, like lime or activated carbon, is introduced to the flue gas, where it absorbs the SO2. 
  • Waste Product Handling: The by-products or waste generated during FGD, such as gypsum or a dry waste product, are collected and either disposed of or utilized in other applications. 
  • Cleaned Flue Gas, now with reduced SO2 levels, is discharged into the atmosphere through the stack. 

Aravalli Green Wall Project 

Context: On the World Environment Day 2025, the Prime Minister of India planted the first sapling (Sindoor/Vermillion tree) in Delhi's Ridge to officially launch the Aravalli Green Wall Project to restore the Aravalli mountain range. 

Relevance of the Topic: Prelims: Key facts about the Aravalli Green Wall Project; United Nations Convention to Combat Desertification (UNCCD); National Action Plan to Combat Desertification and Land Degradation. 

Aravalli Green Wall Project

  • Aim: Restore the 700-km Aravalli mountain range’s ecology through reforestation and conservation efforts across Delhi, Haryana, Rajasthan, and Gujarat.
  • To create a 1400 km-long, 5 km-wide green belt inspired by Africa's Great Green Wall. 
  • The project will use innovative plantation techniques, and that all plantation activities will be geo-tagged and monitored via the Meri LiFE portal to ensure transparency and effectiveness.

Key initiatives under the Project: 

  • Plant native species, revive 75 water bodies, and bolster soil conservation targeting 1.1 million hectares by 2027.
  • Expand green cover in a 5-km buffer zone along the Aravalli range
  • Develop around 1,000 nurseries to support continuous plantation drives and engage local communities.
  • Transform the region into a thriving hub for eco-tourism and sustainable travel. 

Significance: 

  • Green barriers would prevent eastward expansion of the Thar Desert, prevent soil erosion, desertification and dust storms. 
  • Enhance biodiversity and ecosystem services by planting native tree species, providing habitat for wildlife and improving water quality and quantity.
  • Help in carbon sequestration and mitigating climate change.
  • Promote sustainable development and livelihood opportunities by involving local communities in afforestation, agro-forestry and water conservation activities.
  • Contribute to India's commitments under various international conventions such as:
    • UNCCD (United Nations Convention to Combat Desertification)
    • CBD (Convention on Biological Diversity)
    • UNFCCC (United Nations Framework Convention on Climate Change).
  • Enhance India's image as a global leader in environmental protection and green development.

United Nations Convention to Combat Desertification (UNCCD):

  • Established in 1994, UNCCD is the sole legally binding international agreement linking environment and development to sustainable land management.
  • The convention addresses specifically the arid, semi-arid and dry sub-humid areas, known as the drylands.
  • UNCCD is committed to a bottom-up approach, encouraging the participation of local people in combating desertification and land degradation.
  • The member parties work together to improve the living conditions for people in drylands, to maintain and restore land and soil productivity, and to mitigate the effects of drought.
  • UNCCD collaborates closely with the other two Rio Conventions: UNCBD and UNFCCC to meet these complex challenges with an integrated approach and the best possible use of natural resources.

National Action Plan to Combat Desertification and Land Degradation:

  • The National Action Plan to Combat Desertification 2023 takes due consideration of India’s commitments for:
    • Restoration of 26 million hectares of degraded land by 2030.
    • Generating an additional carbon sink of 2.5-3 billion tonnes of CO2 equivalent by 2030 through additional forest and tree cover.
    • Initiative for enhanced South-South Cooperation to share experiences on Sustainable Land Management (SLM) strategies. 
  • India is a party to the UN Convention to Combat Desertification (UNCCD).

Aravalli Mountain Range

  • Oldest mountain ranges (fold mountains) in the world having its origin in the Proterozoic era.
  • It runs approximately 700 kms from north-east to south-west direction, in western India. 
  • Range States: Delhi, Haryana, Rajasthan, Gujarat
  • Divided into two sections: Sambhar-Sirohi ranges and Sambhar-Khetri ranges.
  • Highest Peak: Guru Shikhar on Mount Abu.
image 13

Threats: 

  • Decades of deforestation, mining, livestock grazing, and human encroachment have severely degraded the range. 
  • Of the total degraded area, 81% is in Rajasthan alone, followed by Gujarat, Haryana and Delhi.
  • It has led to drying lakes, damaged aquifers, reduced biodiversity, and increasing desertification risks.

Significance of Aravalli Mountain Range:

  • Vital ecological barrier that prevents the eastward expansion of the Thar desert and protects cities such as Delhi, Jaipur and Gurugram from desertification.
  • Gives rise to several rivers including Banas & Sahibi (Tributaries of Yamuna), Luni (flows into Rann of Kutch), Chambal, Sakhi, and Sabarmati.
  • Performs the role of an aquifer with its highly fractured and weathered quality rocks allowing water to percolate and recharge the groundwater.
  • Its forests, grasslands and wetlands support endangered plant and animal species.
  • Rich in natural resources including minerals such as rock phosphate, lead-zinc-silver, talc, pyrophyllite, asbestos, etc. 

What caused the massive eruption of Italy’s Mount Etna? 

Context: Recently, Mount Etna, the largest volcano in Europe erupted. 

Relevance of the Topic: Prelims: Key facts related to Mount Etna and cause behind its eruption.

About Mount Etna:  

  • Location: Mount Etna is located on the east coast of Sicily. Sicily is the largest island in the Mediterranean Sea, situated just off the toe of the Italian “boot” (Southern Italy).
image 7
  • Mount Etna is the largest active volcano in Europe.
  • It is an active Stratovolcano.  
  • Mount Etna has the highest peak in Italy south of the Alps.
  • Etna has been a World Heritage Site since 2013.
  • It is known for frequent eruptions. Since 1600, at least 60 flank eruptions and many more summit eruptions have happened. 
  • Etna’s summit has five craters, which are responsible for most of the volcano’s eruptions.

What caused the massive eruption of Italy’s Mount Etna?

  • Experts suggest that the eruption began with an increase in pressure inside the volcano due to expanding gases, which led to the collapse of the southeast crater, resulting in hot lava flows.

What kind of eruption did it have?

Scientists typically classify eruptions based on how explosive they are.

image 8
  • According to Italy’s National Institute of Geophysics and Volcanology (INGV) Etna Observatory, the volcano was witnessing a “Strombolian” eruption.

Strombolian eruption: 

  • This type of eruption is usually characterised as discreet moderately explosive bursts which can eject chunks of rock and cinders that can travel hundreds of metres into the air. It occurs due to the presence of gas in the magma chamber within the volcano.
  • The Strombolian eruption is named after another Italian volcano called Stromboli, which produces minor eruptions every 10 to 20 minutes.
image 10
  • However, some volcanologists believe that Mount Etna did not experience a Strombolian eruption but rather a Plinian eruption, in which hot gas, ash, and rock can explode high enough to reach the stratosphere.
image 9

Urban Flooding

Context: India’s urban centres- Mumbai, Delhi, Kolkata, Hyderabad, and several other cities are getting flooded more often in the recent past. The reasons range from inefficient drainage systems to the implications of climate change. This is having an increasing impact on life, property and increased incidence of tropical diseases. 

Relevance of the Topic:Mains: Urban Flood: Causes, Consequences, Way Forward.

About Urban Flooding

Urban flooding has become increasingly frequent in India's major cities (Chennai floods, most recent in Hyderabad), with an increasing impact on life, property and increased incidence of tropical diseases.

Natural Factors Contributing to Urban Flooding in India:

  • Monsoon Rains:
    • Example: The Indian subcontinent experiences heavy monsoon rains from June to September. Cities like Mumbai, Chennai, and Kolkata frequently face intense rainfall during this period, leading to waterlogging and urban flooding.
  • Topography:
    • Example: Bengaluru's natural topography, with its undulating terrain, can lead to water accumulation in low-lying areas. This becomes problematic when combined with urban development that disrupts natural drainage patterns.
  • Cyclones and Storm Surges:
    • Example: Coastal cities such as Chennai, Visakhapatnam, and Mumbai are susceptible to cyclones and storm surges. The 2017 Cyclone Ockhi caused significant flooding and damage in coastal areas of Tamil Nadu and Kerala.
  • Soil Characteristics:
    • Example: Certain soil types, such as clayey soils found in parts of Chennai, have low permeability, leading to poor drainage and increased surface runoff during heavy rains.
  • Sea Level Rise:
    • Example: Coastal cities like Mumbai and Chennai are vulnerable to sea level rise, which can exacerbate flooding, particularly during high tides and storm surges. The 2019 floods in Mumbai were worsened by high tide conditions.
  • Climate Change:
    • Example: The increasing frequency and intensity of extreme weather events due to climate change are causing more severe and unpredictable rainfall patterns. For instance, the unprecedented rainfall in Kerala in 2018 led to widespread flooding.
  • Hills and Slopes:
    • Example: Shimla and other hill cities experience rapid runoff due to their steep slopes, leading to flash floods during heavy rains. The terrain accelerates water flow, increasing the risk of flooding in lower-lying urban areas.
  • Seasonal Variability:
    • Example: Cities like Lucknow experience seasonal variability in rainfall, with some years receiving exceptionally high rainfall. This variability can overwhelm urban drainage systems not designed for such fluctuations.

Anthropogenic factors

Anthropogenic factors - Urban Flooding
  • Rapid Urbanization without Adequate Planning:
    • Example: The city of Gurgaon, near Delhi, has seen rapid urban development without corresponding improvements in infrastructure. The lack of adequate drainage systems has led to frequent waterlogging during monsoon seasons.
  • Encroachment on Natural Water Bodies:
    • Example: In Chennai, extensive encroachment on natural water bodies and wetlands has significantly reduced the city's capacity to absorb and drain rainwater. The 2015 floods were exacerbated by the loss of these natural buffers.
  • Outdated Drainage Infrastructure:
    • Example: Mumbai's drainage system, parts of which date back to the British colonial era, is not equipped to handle the high-intensity rainfall the city experiences. The 2005 floods highlighted the inadequacies of the city's drainage system.
  • Poor Solid Waste Management:
    • Example: In Kolkata, improper disposal of solid waste often clogs drainage channels, leading to severe waterlogging during heavy rains. The accumulated waste obstructs water flow, causing flooding even during moderate rainfall.
  • High Population Density:
    • Example: Delhi's high population density puts immense pressure on existing drainage infrastructure. During the 2020 monsoon, several areas of the city experienced severe flooding due to the overburdened drainage system.
  • Illegal Construction:
    • Example: In Hyderabad, illegal constructions along the Musi River and other watercourses have obstructed natural water flow paths, leading to increased flooding during the monsoon season.
  • Lack of Urban Green Spaces:
    • Example: Bengaluru has lost a significant number of its lakes and green spaces to urban development. The reduced capacity for water absorption has led to frequent flooding in several parts of the city.
  • Water Mismanagement:
    • Example: In Surat, the release of water from the Ukai Dam without adequate warning during heavy rains in 2006 led to severe flooding. Poor water management practices and coordination issues often exacerbate flooding.
  • Unplanned Urban Expansion:
    • Example: Jaipur has expanded rapidly without proper urban planning, leading to the development of residential areas in low-lying regions prone to flooding. The lack of planned drainage networks has made these areas vulnerable to flooding during heavy rains.

 Strategies to Curb Urban Flooding:

  • Green Infrastructure:
    • Green Roofs: Installing vegetation on rooftops can absorb rainwater and reduce runoff.
    • Permeable Pavements: Using materials that allow water to infiltrate the ground can reduce surface runoff.
    • Rain Gardens: Small, vegetated areas designed to absorb and filter rainwater.
  • Stormwater Management Systems:
    • Retention Basins: Constructing basins to hold excess rainwater and release it slowly.
    • Detention Ponds: Similar to retention basins but usually dry until a storm event occurs.
    • Bioswales: Landscaped channels designed to concentrate and convey stormwater runoff while removing debris and pollution.
  • Upgrading Drainage Infrastructure:
    • Enlarging and Improving Drainage Systems: Ensuring that drainage systems are capable of handling increased volumes of water.
    • Regular Maintenance: Keeping drainage systems clear of debris and in good repair.
  • Urban Planning and Zoning:
    • Floodplain Management: Restricting development in areas prone to flooding.
    • Elevated Structures: Building homes and infrastructure above anticipated flood levels.
  • Smart Technology and Data:
    • Flood Monitoring Systems: Using sensors and IoT devices to monitor water levels and provide early warnings.
    • Predictive Modeling: Utilizing data and simulations to predict flooding and plan responses.
  • Community Involvement and Education:
    • Public Awareness Campaigns: Educating residents about flood risks and how to reduce their impact.
    • Community-Led Projects: Encouraging local initiatives to implement flood mitigation measures.
  • Nature-Based Solutions:
    • Wetland Restoration: Rehabilitating wetlands to act as natural sponges for rainwater.
    • Urban Forests: Increasing tree cover to enhance water absorption and reduce runoff.
  • Regulatory Measures:
    • Building Codes: Implementing stringent building codes that require flood-resilient construction.
    • Stormwater Fees: Charging fees based on impervious surface area to fund flood mitigation projects.

Case Studies:

Several cities worldwide have adopted the sponge city approach, with notable examples including:

  • Shanghai, China: Implementing green roofs, permeable pavements, and extensive green spaces as part of its sponge city initiative.
  • Berlin, Germany: Utilizing green roofs, rain gardens, and retention basins to manage stormwater and improve urban resilience.
  • Singapore: Integrating green infrastructure and advanced drainage systems to transform the city into a model of sustainable water management.

As the incidence of extreme weather events due to climate change, there must be more focus on urban flooding. Guidelines laid down by NDMA for urban flooding should be followed by cities

Centre notifies guidelines to boost Electric Car Manufacturing in India 

Context: The Ministry of Heavy Industries (MHI) has notified the Scheme to Promote Manufacturing of Electric Passenger Cars in India (SPMEPCI). 

Relevance of the Topic: Prelims: Key facts related to SPMEPCI & associated guidelines.

Scheme to Promote Manufacturing of Electric Passenger Cars in India

The scheme aims to:

  • Boost domestic EV manufacturing by significantly reducing import duties for foreign manufacturers that commit to investing in local production.
  • Attract global investments in electric vehicles (EV) and position India as a global automotive manufacturing hub.

Key Features of SPMEPCI: 

  • Approved companies will be allowed to import up to 8,000 Completely Built Units (CBUs) of electric four-wheelers (e-4W) annually at a reduced customs duty of 15% (subject to a minimum CIF value of USD 35,000 per unit) for a period of five years.
  • To qualify for these benefits:
    • Applicants must commit to a minimum investment of Rs 4,150 crore within 3 years of receiving approval. They must establish manufacturing facilities and commence production within this period. 
    • They must achieve minimum domestic value addition (DVA) of 25% within 3 years, and minimum DVA of 50% within 5 years from the date of issuance of approval letter.
    • They should have global revenues of ₹10,000 crore at the time of application to qualify and receive benefits. 
  • Total duty foregone will be limited to either Rs 6,484 crore or the actual investment made by the applicant, whichever is lower.

Foreign companies can invest in existing EV manufacturing setups in India (brownfield investments), instead of only setting up entirely new factories earlier (greenfield investments).

Significance of SPMEPCI guidelines: 

  • Boosts Domestic Manufacturing: Attracts global EV companies to set up factories in India, strengthening the Make in India and Atma Nirbhar Bharat initiatives.
  • Encourages EV Adoption: Makes electric vehicles more affordable to Indian consumers through reduced import duties.
  • Promotes Investment & Technology Transfer: Ensures large-scale investments, local job creation, and introduction of advanced EV technologies.

The scheme aligns with India’s climate goals, including its commitment to achieve net-zero emissions by 2070. It will also foster environmental sustainability through strategic policy interventions in the EV ecosystem.

Going Beyond AQI: Why Toxicity Matters in Measuring Air Pollution

Context: A study has found that the toxicity of air pollution changes with the concentration levels of PM2.5 in Indian cities, bringing attention to a critical gap in current air quality standards.

Relevance of the Topic:  Prelims: PM2.5, Air Quality Index (AQI), Reactive Oxygen Species (ROS), Oxidative Stress, Pollution Sources.

What is PM2.5?

  • PM2.5 refers to fine particulate matter with a diameter of less than 2.5 micrometres, small enough to penetrate deep into the lungs and bloodstream. 
  • It originates from sources- biomass and solid waste burning, vehicular emissions, industrial activities, construction dust etc. 
  • Due to its size and chemical composition, PM2.5 is associated with respiratory, cardiovascular, and neurological disorders.
image 4
  • A recent study by Indian researchers has highlighted how toxicity of air pollution changes with concentration levels of PM 2.5 in Indian cities.

Key Highlights of the Study:

The study- “Contrasting features of winter-time PM2.5 pollution and PM2.5-toxicity based on oxidative potential” (2016-2023), conducted in Kolkata, found the following:

  • Pollution is damaging even at lower concentrations, but itsability to cause damage to cells increases sharply after the concentration level crosses a certain threshold value.
    • When PM2.5 concentration level exceeds about 70 µg/m³, its potential to create oxidative stress in the body increases steeply, and continues to rise until the concentration reaches about 130 µg/m³. 
    • Toxicity stabilises after that, and further increase in concentration do not lead to an appreciable rise in damage potential.
  • The threshold level is expected to vary from city to city. E.g., This threshold value is about 70 micrograms per cubic metre (µg/m³) for Kolkata. 
  • Threshold level of toxicity varies due to differences in the composition of air pollutants. E.g., pollutants from biomass and solid waste burning contribute more significantly to toxicity than those from vehicular emissions.

Why does toxicity increase after a point?

At lower concentrations the body can manage pollutant effects, but beyond a threshold the defences of the body are overwhelmed.

  • When pollutants are inhaled, the body’s immune system fights back through the release of Reactive Oxygen Species (ROS), which are chemicals used by immune cells to neutralise foreign substances. When larger concentrations of pollutants are inhaled, greater amounts of ROS are released.
  • The problem is ROS is damaging for the body’s cells as well. Therefore, as a natural counter-defence mechanism, the body produces another set of chemicals called antioxidants, that protect the cells against ROS.
  • However, antioxidants are present in small quantities, and take time to build up. So, while they are able to effectively deal with smaller amounts of ROS, they are helpless when ROS is produced in large amounts. This leads to an imbalance in the body, a situation called oxidative stress, which leaves the internal cells prone to damage from excess ROS.

Current Air Quality Standards: 

  • Air quality standards are framed in terms of their concentration, not toxicity. E.g., in India, a PM2.5 concentration level of 40 µg/m³ averaged over a year is considered safe. On a daily basis, a concentration of 60 µg/m³ is considered safe.
  • However, the harmful impacts of air pollution on human health depend not just on concentration, but also on toxicity, which takes into account factors like chemical composition of pollutants.

Way Forward

The study underlines a crucial gap in how we currently assess and respond to air pollution. It calls for a nuanced, city-specific and health-focused approach to pollution control. 

  • Incorporate toxicity into AQI systems: AQI should reflect not only PM2.5 concentration but also its oxidative potential, giving a more accurate picture of health risks.
  • Develop city-specific toxicity thresholds: Since pollutant composition varies by location, region-specific toxicity thresholds must be established for effective local interventions.
  • Revise Air Quality Standards: National standards must evolve to include toxicity measures.

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