Current Affair 1:

Seagrasses

 

Seagrasses are found in shallow salty and brackish waters in many parts of the world, from the tropics to the Arctic Circle. Seagrasses are so-named because most species have long green, grass-like leaves. Seagrasses are marine flowering plants, found on all continents except Antarctica. They have roots, stems and leaves and produce flowers and fruits. The closest relatives to seagrass, on land, are the monocots – grasses, lilies and palms.

One thing to note is that seagrass is different from seaweed:

Even though seagrasses and seaweeds look superficially similar, they are very different organisms. Seagrasses belong to a group of plants called monocotyledons that include grasses, lilies and palms.

Where Are Seagrasses Found?

Seagrasses grow in salty and brackish (semi-salty) waters around the world, typically along gently sloping, protected coastlines. Because they depend on light for photosynthesis, they are most commonly found in shallow depths where light levels are high.

India, being in the Indo-Pacific region, has high seagrass diversity: 14 species belonging to 7 genera. The Gulf of Mannar and Palk Strait house all the 14 species found in India, while the Lakshadweep and Andaman and Nicobar Islands have 8 and 9 species respectively.

Growth & Reproduction

Seagrasses grow both vertically and horizontally—their blades reach upwards and their roots down and sideways—to capture sunlight and nutrients from the water and sediment. They spread by two methods: asexual clonal growth and sexual reproduction. Enough.

Ecosystem Benefits

Seagrasses are often called foundation plant species or ecosystem engineers because they modify their environments to create unique habitats. These modifications not only make coastal habitats more suitable for the seagrasses themselves, but also have important effects on other animals and provide ecological functions and a variety of services for humans.

1. Modification of the Physical Environment:

Seagrasses are known as the "lungs of the sea" because one square meter of seagrass can generate 10 liters of oxygen every day through photosynthesis. Seagrass leaves also absorb nutrients and slow the flow of water, capturing sand, dirt and silt particles. Their roots trap and stabilize the sediment, which not only helps improve water clarity and quality, but also reduces erosion and buffers coastlines against storms.

1. Creation of Living Habitat:

Seagrasses are often called nursery habitats because the leafy underwater canopy they create provides shelter for small invertebrates (like crabs and shrimp and other types of crustaceans), small fish and juveniles of larger fish species. Many species of algae and microalgae (such as diatoms), bacteria and invertebrates grow as “epiphytes” directly on living seagrass leaves, much like lichens and Spanish moss grow on trees.

1. Blue Carbon:

Seagrasses are capable of capturing and storing a large amount of carbon from the atmosphere. It has been estimated that in this way the world's seagrass meadows can capture up to 83 million metric tons of carbon each year. Atmospheric carbon is captured by coastal mangroves, seagrasses and salt marshes at a rate five times faster than tropical forests.

What are the main threats to seagrasses?

Seagrass meadows are experiencing rates of loss that may be as high as 7% of their total global area per year. The natural causes of seagrass destruction are cyclones, intensive grazing, fungal and other infestations and disease. Seagrasses in the intertidal habitat are prone to drying out. In estuaries, increased freshwater incursion and siltation can also destroy seagrass beds.

However, the most significant threat is (you guessed it) from human activities. Large amounts of pollutants, including chemicals and excessive nutrients like fertilizers wash off the coast and directly into seagrass beds, causing algal blooms that can block off sunlight. Sediments can choke the leaves and dredging can completely fragment seagrass meadows. Boat anchors and large marine debris can kill sections of seagrass meadows.

Current Affair 2:

National Tiger Conservation Authority.

 

The National Tiger Conservation Authority is a statutory body under the Ministry of Environment, Forests and Climate Change constituted under enabling provisions of the Wildlife (Protection) Act, 1972, as amended in 2006, for strengthening tiger conservation, as per powers and functions assigned to it under the said Act.

You will the entire function of NTCA given below. Once you read entire functions, it will give you confidence while solving questions related to this.

 

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