1.South American lungfish

Source – the hindu

Recent study revealed that the South American lungfish genome grew massively during the past 100 million years.

About South American lungfish: 

• It is a freshwater species (Lepidosiren paradoxa).
• It is the nearest living relative to the first land vertebrates and closely resembles its primordial ancestors dating back more than 400 million years.
• Distribution: It is mainly inhabiting slow-moving and stagnant waters in Brazil, Argentina, Peru, Colombia, Venezuela, French Guiana and Paraguay.
• It has the largest genome compared to any of the animals on the earth.
  • The length of the DNA in each cell of this lungfish would extend almost 60 metres. The human genome would extend a mere 2 metres.
  • Its genome is more than 50 times the human genome’s size.
  • The world’s four other lungfish species live in Africa, also with large genomes.
  • Its genomes are largely composed of repetitive elements – about 90% of the genome.

Key features of Lungfish

• Lungfish first appeared during the Devonian Period.
• While other fish rely upon gills to breathe, lungfish also possess a pair of lung-like organs.
• It lives in oxygen-starved, swampy environs of the Amazon and Parana-Paraguay River basins, and supplements the oxygen gotten from the water by breathing in oxygen from the air.

2.Miyawaki Method

The Chhattisgarh Forest Department recently organised a Van Mahotsav programme in the Manendragarh-Chirmiri-Bharatpur (MCB) district by planting saplings using the Miyawaki method.

About Miyawaki Method:

• It is a method of afforestation developed by the Japanese botanist and plant ecology expert Professor Akira Miyawaki.
• It involves planting two to four types of indigenous trees within every square meter.
• Due to the dense planting, the seedlings grow quickly as they compete for sunlight.
• Only native species that would occur naturally in that area without humans, given the specific climate condition, are planted. 
• The selection of species to plant in a given area was originally linked to the theory of potential natural vegetation (PNV), in other words, the vegetation that would occur in a specific area without further human interference.
• In this method, the trees become self-sustainable and grow to their full length within three years.
• Miyawaki forests grow 10x faster, are 30x denser and contain 100x more biodiversity. 
• They are quick to establish, maintenance-free after the first two-to-three years, and can be created on sites as small as 3 sq. m.
• The goals of a Miyawaki technique include improving biodiversity, sequestering carbon, increasing green cover, lowering air pollution, and preserving the water table.
• Miyawaki forests are viable solutions for cities looking to rapidly build climate resilience.

It is effective because it is based on natural reforestation principles, i.e., using trees native to the area and replicating natural forest regeneration processes.

3. Bunni Grassland

Recently, in a new study, researchers in Bhuj, have assessed the suitability of different areas of Banni for sustainable grassland restoration, considering ecological value to be the primary criterion.

About Banni Grasslands

• It is located along the northern border of Kachchh district in the state of Gujarat.
• The Banni is also home to 22 ethnic groups, the majority of whom are pastoralists.
• It is home to great biological diversity, having 37 grass species, 275 bird species, and domesticated animals like Buffalo, Sheep, Goat, Horses and Camel, as well as wildlife. 
• The Kutch Desert Wildlife Sanctuary and Chhari Dhand Conservation Reserve are part of the Banni Grasslands.
• Flora: The vegetation here mainly comprises Prosopis Juliflora, Cressa critica, Cyperus spp, Sporobolus, Dichanthium, and Aristida.
• Fauna:It is home to mammals such as the Nilgai, Chinkara, Blackbuck, Wild boar, Golden Jackal, Indian Hare, Indian Wolf, Caracal, Asiatic Wildcat and Desert Fox etc. 

Key facts about Grasslands

• These are one of the largest ecosystems in the world.
• They are distributed mainly in semiarid and arid areas, and include savannahs, grassy shrublands, and open grasslands.
• Ecological benefits: They harbour a large number of unique and iconic species and offer a variety of material and intangible advantages to people, including several ecosystem services such as carbon storage, climate mitigation, and pollination.
• Threats: They face the problem of degradation due to deforestation, overgrazing, agriculture, urbanisation, and other natural and human-made reasons. As much as 49% of grassland areas worldwide are estimated to be experiencing degradation.
• In India, grasslands account for approximately eight lakh sq. km, or about 24% of the country’s total land area (32.8 lakh sq. km).

4.Parvorirus 19

The US centres for Disease Control and Prevention (CDC) recently issued a healthy advisory due to concerning rise in cases of parvovirus B19.

About Parvovirus B19:

• It is a highly contagious and common illness, particularly in those with weakened immune systems. 
• It is commonly known as the “slapped cheek” illness due to the characteristic reddening of the cheeks it causes. 
• Parvovirus infection has also been known as ‘Fifth disease’ because, historically, it was fifth in a list of common childhood illnesses characterized by a rash.
• Transmission:
  • The virus can be spread through airborne droplets when an infected person coughs or sneezes.
  • It may also spread through blood or contaminated blood products.
  • Pregnant people with parvovirus can spread the virus to the fetus through the placenta.
• Complications:
  • In most children, parvovirus infection is mild and needs little treatment.
  • But in some adults, the infection can be serious. Parvovirus infection in some pregnant women can lead to serious health problems for the fetus.
  • The infection is also more serious for people with some kinds of anemia or who have a compromised immune system.
• Symptoms:
  • Most people with parvovirus infection have no signs or symptoms.
  • When symptoms do appear, they vary greatly depending on how old you are when you get the disease.
  • Common symptoms include “slapped cheek” rash in children, and joint pains in adults.
• Treatment:
  • Parvovirus B19 infections are usually mild and will go away on their own.
  • Treatment usually involves relieving symptoms, such as fever, itching, and joint pain and swelling. 

5. Zinc

Researchers in France have discovered that zinc plays a crucial role in the health of legume crops.

About Zinc: 

• It is a silvery blue-grey metal with a relatively low melting and boiling point.
• Both lead & zinc are found to occur together in ore along with other metals like silver and cadmium.
• It is the fourth most widely used metal across the globe, trailing only steel, aluminium and copper. India has self-sufficiency in respect of zinc.
• In India, Rajasthan is endowed with the largest reserves/resources of lead – zinc ore, followed by Andhra Pradesh (3.03%), Madhya Pradesh (1.98%), Bihar etc.
• Global reservoirs of Zinc: Australia accounts for 27% of world’s zinc reserves, followed by China (18%), Russia & Mexico (9% each), Peru(8%), Kazakhstan(5%), USA(4%), etc.
• Uses:
  • The largest consumer of zinc is the Galvanising Industry. Owing to its corrosion resistance in varied types of environment, zinc is used for protecting steel by way of galvanizing.
  • Large quantities of zinc are used to produce die-castings, which are important in the automobile, electrical and hardware industries.
• Zinc oxide is widely used in the manufacture of very many products such as paints and rubber etc.
• Biological role
  • It is a trace mineral, meaning that the body only needs small amounts, and yet it is necessary for almost 100 enzymes to carry out vital chemical reactions.
  • It is a major player in the creation of DNA, growth of cells, building proteins, healing damaged tissue, and supporting a healthy immune system.

Key findings

• It found that zinc in plantsaids in nitrogen fixation, a process where atmospheric nitrogen is converted into ammonia, an essential nutrient for plants.
  • Legume crops form a symbiotic relationship with rhizobia, a bacteria that fixes atmospheric nitrogen in root nodules. 
  • However, these nodules are sensitive to environmental factors such as temperature, drought, flooding, soil salinity, and high soil nitrogen levels.
• Another vital finding of this study is the identification of a crucial transcription factor that controls nodule breakdown when soil nitrogen levels are high. 
• The researchers discovered that legumes also use zinc as a secondary signal to integrate environmental factors and regulate nitrogen fixation efficiency. The mechanism works due to a transcriptional regulator called Fixation Under Nitrate (FUN).
• FUN is inactivated by zinc through the formation of large filament structures, which are dismantled to release active FUN when zinc levels are low.