[DAY 12] 60 DAY RAPID REVISION (RaRe) SERIES for UPSC Prelims 2022 – Environment, CURRENT AFFAIRS & CSAT; Test Series, Videos & Notes!

Solution (a)

Explanation:

Chronologically, the following organisms evolved in the sequence given below – 

• Corals
• Fishes
• Birds
• Flowering plants

Solution (a)

Explanation:

Wetlands (Conservation and Management) Rules, 2017:

• A wetland includes areas of marine water the depth of which at low tide does not exceed six meters.
• According to the Convention, wetlands include almost any habitat where water is a key to the environment and its wildlife.
• Wetlands include swamps, marshes, billabongs, lakes, salt marshes, mud flats, mangroves, coral reefs, fens, peat bogs, or bodies of water – whether natural or artificial, permanent or temporary.
• Water within these areas can be static or flowing; fresh, brackish or saline; and can include inland rivers and coastal or marine water to a depth of six metres at low tide. There are even underground wetlands.
• Anywhere from estuaries, lakes and rivers to underground aquifers, mangroves, coral reefs and rice paddies count.

Solution (b)

Statement Analysis:

Notes:

Periphyton: These are organisms which remain attached to stems and leaves of rooted plants or substances emerging above the bottom mud such as sessile algae.

Plankton: Microscopic floating organisms such as algae, diatoms, protozoans and larval forms are called plankton. This group includes both microscopic plants like algae (phytoplankton) and animals like crustaceans and protozoans (zooplankton).

Solution (b)

Statement Analysis:

Solution (a)

Statement Analysis:

Solution (b)

Statement Analysis:

Notes:

Ramsar convention:

• The Convention on Wetlands is the intergovernmental treaty that provides the framework for the conservation and wise use of wetlands and their resources. 
• The Convention was adopted in the Iranian city of Ramsar in 1971 and came into force in 1975. Since then, almost 90% of UN member states, from all the world’s geographic regions, have acceded to become ‘Contracting Parties’.
• Every three years, representatives of the contracting parties meet as the Conference of the Contracting Parties (COP), the policy-making organ of the convention which adopts decisions (resolutions and recommendations) to administer the work of the convention and improve the way in which the parties are able to implement its objectives.
• The Ramsar Convention works closely with six other organisations known as International Organization Partners (IOPs). These are:

1. BirdLife International.
2. International Union for Conservation of Nature (IUCN).
3. International Water Management Institute (IWMI)
4. Wetlands International
5. WWF International
6. Wildfowl & Wetlands Trust (WWT)

Solution (c)

Statement Analysis:

Notes:

Photic zone:

• It is the upper layer of the aquatic ecosystems, up to which light penetrates and within which photosynthetic activity is confined. 
• The depth of this zone depends on the transparency of water. Both photosynthesis and respiration activity takes place.
• Photic (or ‘euphotic’) zone is the lighted and usually well-mixed portion that extends from the lake surface down to where the light level is 1% of that at the surface.

Aphotic zone:

• The lower layers of the aquatic ecosystems, where light penetration and plant growth are restricted form the aphotic zone. Only respiration activity takes place. 
• Aphotic zone is positioned below the littoral and photic zones to bottom of the lake where light levels are too low for photosynthesis. 
• Respiration occurs at all depths so the aphotic zone is a region of oxygen consumption. This deep, unlit region is also known as the profundal zone.

Solution (b)

Statement Analysis:

Solution (d)

Explanation:

Causes of coral bleaching:

• There are a number of stresses or environmental changes that may cause bleaching. These causes include disease, excess shade, increased levels of ultraviolet radiation, sedimentation, pollution, salinity changes, and increased temperatures.
• Increased exposure to ultraviolet (UV) radiation;
• Large amounts of stormwater from heavy rains flooding the reef;
• The exposure of coral to certain chemicals or diseases;
• Sediments such as sand or dirt covering the coral;
• Excess nutrients such as ammonia and nitrate from fertilizers and household products entering the reef ecosystem. (The nutrients might increase the number of zooxanthellae in the coral, but it is possible that the nutrient overload increases the susceptibility of coral to diseases.)

Solution (a)

Statement Analysis:

Notes:

Freshwater ecosystems can be divided into two categories:

Lentic ecosystem:

• It entails a body of standing water, ranging from ditches, seeps, ponds, seasonal pools, basin marshes, swamp and lakes.
• These are also known as Pond ecosystem.

Lotic ecosystem:

• It can be any kind of moving water, such as a run, creek, brook, river, spring, channel or stream.
• The water in a lotic ecosystem, from source to mouth, must have atmospheric gases, turbidity, longitudinal temperature gradation and material dissolved in it.

Solution (d)

Statement Analysis:

Solution (d)

Statement Analysis:

Solution (b)

Statement Analysis:

Notes:

Zones of the ocean:

• Infralittoral zone– This zone is dominated by the algae and has depth of about 16.40 feet below the low water mark.
• Circalittoral zone– This zone is dominated by the sessile animals like Oysters.
• Subtidal zone– It is the lower most part of neritic zone and below the ocean’s intertidal zone. This zone is never exposed to the atmosphere.

Solution (a)

Explanation:

Montreux record:

• The Montreux Record is a register of wetland sites on the List of Wetlands of International Importance where changes in ecological character have occurred, are occurring, or are likely to occur as a result of technological developments, pollution or other human interference. 
• It is the principle tool under the Ramsar convention for highlighting wetlands sites in need of priority conservation status. It is maintained as part of the Ramsar Database and is subject to continuous review.
• It is maintained as part of the Ramsar List.
• At present 2 Indian sites are listed under it. (Loktak Lake, Manipur and Keoladeo National Park, Rajasthan)
• In 1993 Chilka lake was also listed in Montreux record due to problem of Siltation. But later in 2002, it was removed from the list as problem tackled by government actions.

Solution (c)

Statement Analysis:

Biomes of India:

• The term biome means the main groups of plants and animals living in areas of certain climate patterns.
• It includes the way in which animals, vegetation and soil interact together.
• The plants and animals living in the area are adapted to that environment. 
• The five biomes of India are:

1. Tropical Humid Forests
2. Tropical Dry or Deciduous Forests (including Monsoon Forests)
3. Warm deserts and semi-deserts
4. Coniferous forests and
5. Alpine meadows

Solution (c)

Statement Analysis:

Coastal Regulation Zone:

CRZ along the country has been placed in four categories, which are as follows:

• CRZ I – Ecologically Sensitive Areas
  • They lie between low and high tide line.
  • Exploration of natural gas and extraction of salt are permitted.
• CRZ II – Shore Line Areas
  • The areas that have been developed up to or close to the shoreline.
  • Unauthorized structures are not allowed to construct in this zone.
• CRZ III – Undisturbed Area
  • Rural and Urban localities which fall outside I and II.
  • Only certain activities related to agriculture even some public facilities are allowed in this zone.
• CRZ IV – Territorial Area

• • An area covered between Low Tide Line and 12 Nautical Miles seaward.
  • Fishing and allied activities are permitted in this zone.
  • Solid waste should be let off in this zone.

Changes made to the regulatory framework-

• The system of granting clearances has been changed. States will have the authority to approve proposals for urban (CRZ-II) and rural (CRZ-III) areas.
• The Ministry of Environment, Forests and Climate Change will grant clearances for ecologically sensitive areas (CRZ-I), and areas falling between the low tide line and 12 nautical miles seaward.
• The modifications also include demarcation of a 20-metre no development zone for all islands and guidelines to deal with sensitive areas.

Solution (d)

Explanation:

Adaptation is any attribute of the organism (morphological, physiological, behavioural) that enables the organism to survive and reproduce in its habitat. Many adaptations have evolved over a long evolutionary time and are genetically fixed.

Adaptations by plants in desert areas:

1. Thick cuticle on their leaf surfaces
2. Stomata are arranged in deep pits
3. Stomata to remain closed during day time
4. Flattened stems

Solution (c)

Explanation:

Solution (a)

Statement Analysis:

Solution (c)

Statement Analysis:

Notes:

Khijadia Wildlife Sanctuary in Gujarat and Bakhira Wildlife Sanctuary in Uttar Pradesh were announced as Ramsar sites on the occasion of World Wetland Day 2022 (2nd January 2022) held at Sultanpur National Park, a Ramsar site in Haryana.

Solution (d)

Statement Analysis:

Context – There was an outbreak of Nipah Virus in Kerala.

Solution (b)

Statement Analysis:

Context – The Prime Minister of India addressed the forum

Solution (c)

Ministry of Information and Broadcasting has constituted a ten member Committee headed by Shri Ashok Kumar Tandon, renowned Journalist and Member, PrasarBharati. The committee was tasked to take a look at the existing guidelines of Journalists Welfare Scheme of the Ministry of Information and Broadcasting.

Solution (a)

Statement Analysis:

Context – Archeologists have found ‘shankhalipi’ inscriptions on the stairs on an ancient temple dating back to the Gupta period in Uttar Pradesh’s Etah district

Solution (c)

Statement Analysis:

Context – India’s highest altitude institute in Ladakh gets LiFi network for faster internet

Solution (d)

The bus stops at point C for 1/4 hour due to blockage.

Let the initial speed be x Km/h

Time = Distance/Speed

Time to travel the distance AC = tAC = 150/x hours

Let’s first calculate CB

60% of AB = 150 Km

AB × 0.60 = 150

AB = 150/0.60 = 250 Km

CB = Remaining distance = 250 − 150 = 100 Km

Speed of bus after point C = (x + 20) Km / h

Time to travel the distance CB = tCB = 100/(x + 20) hours

Had there been no blockage, the bus would have traveled at xKm/h. Its travel time would have been:

tusual = AB/x = 250/x hours

The bus reached town B on time, despite blockage, therefore:

Usual time = Time to travel the distance AC + Delay + Time to travel the distance CB

tusual​=tAC​+1/4​+tCB​

250/x​=150/x​+1/4+100/x+20​

Multiplying both sides by 4x(x + 20):

250 × 4(x + 20) = 150 × 4(x + 20) + x(x + 20) + 100 × 4x

1000x + 20000 = 600x + 12000 + x2 + 20x + 400x

1000x + 20000 = x2 + 1220x + 12000

0 = x2 + 1220x − 1000x + 12000 − 20000

x2 +20x − 8000 = 0

The speed is calculated by solving the above quadratic equation. Factorizing the quadratic expression we get:

(x + 100)(x − 80) = 0

x = − 100, or x = 80.

Speed is not a negative quantity, so x = 80Km/h

Solution (b)

The time taken by train is 

t = 720/90

t = 8 hr

Number of stops in 720 km 

Number of stops = (720/80) – 1 (Since final stop is not considered)

Number of stops = 9 – 1

Number of stops = 8 

Time of stopping after every 80 km is 

Total time of stopping = 8 × 4

Total time of stopping = 32 min

The total time to cover 720 km is 8 hr 32 min.

Solution (a)

The length of each train is 150 m

The speed of the faster train is 30 km/hr

The speed of the slower train is 24 km/hr

When a train crosses another train, then distance traveled is the sum of the length of both trains

Time taken = Distance/Speed

Relative Speed = Sum of speeds of trains (when trains are moving in the opposite directions)

As both trains are moving in the opposite direction

Relative speed = (30 + 24) km/hr

⇒ 54 × 5/18 = 15 m/s

Distance = 2 × 150 = 300 m

Time = 300/(15) = 20 sec

The faster trains will cross slower train completely in 20 seconds.

Solution (b)

For statement l

Upstream speed = 40/8 = 5 km/h

Downstream speed = 36/6 = 6 km/h

Speed of stream = (6 – 5)/2 = 1/2 = 0.5 km/h

For statement ll

Since, the train has to cross the whole bridge and length of itself

Speed of train = (1200 + 1600)/120 = 2800/120 m/s = (2800/120) × (18/5) km/h =84 km/h

Therefore, only statement 2 is correct

Solution (a)

Refer to, “The long-term trends for flood impact in India have been one of declining loss of lives and cattle since the decadal high of 1971-80, but rising absolute economic losses, though not as a share of GDP. “

It is clear from the passage that the long term trends of impact of floods in India have been on the decline in terms of lives of people and cattle lost but on the other hand the economic losses have quantified multiple times during this particular time duration. Among the given options, we can choose Option A only since it gives us the correct information regarding the data on lives lost in floods since 1970s till date. Others can be eliminated since they do not follow from the passage.

This makes option(a) the correct choice among the given options.