Environment & Biodiversity Current Affairs MCQs

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A degraded area called the Polo Ground inside Guindy National Park is being restored to support wildlife, especially blackbucks. Guindy National Park is a rare protected urban area located in Chennai, Tamil Nadu. It is home to spotted deer and blackbucks, which rely on open grasslands to survive. Restoration work includes removing invasives, planting seven native grass species, and adding legume plants to improve soil health.

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A new frog species named Leptobrachium aryatium was discovered in Garbhanga Reserve Forest near Guwahati, Assam, after a 21-year-long study. It was first studied in 2004 but misidentified as Leptobrachium smithi. The discovery site lies near Deepor Beel, a Ramsar wetland site, and is part of the Garbhanga-Rani-Deepar Beel elephant corridor. The species was named after Arya Vidyapeeth College, which helped transform the local area from a liquor brewing zone to an educational hub. The frog has orange-and-black eyes, a reticulated throat, and makes rhythmic dusk-time calls. Its identification was confirmed through morphology, DNA analysis, and bioacoustics.

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India is now the second-largest emitter of nitrous oxide (N₂O) in the world after China, raising climate concerns due to N₂O’s high global warming potential. Nitrous oxide (N₂O) is nearly 300 times more potent than carbon dioxide (CO₂) in trapping heat in the atmosphere. Nitrogen makes up around 78% of Earth’s atmosphere and is essential for DNA, adenosine triphosphate (ATP), proteins, and chlorophyll. Plants cannot use nitrogen gas (N₂) directly, so they depend on nitrogen-fixing bacteria called diazotrophs to convert it into usable forms. In the nitrogen cycle, ammonia changes into nitrites (NO₂⁻), then nitrates (NO₃⁻), which plants absorb. Excess nitrates are returned to the atmosphere through denitrification, maintaining balance in the nitrogen cycle.

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The Poas volcano in Costa Rica, one of the country’s top tourist spots, erupted recently, drawing global attention. It is one of the most active volcanoes in Costa Rica and is located inside the Poás Volcano National Park. The volcano is a composite stratovolcano with an irregular shape and a base covering around 400 square kilometers. It stands 2,708 meters above sea level and features a huge main crater about 1.5 kilometers wide and 300 meters deep. This crater is one of the largest active volcanic craters in the world.

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Researchers from the Centre for Peninsular Aquatic Genetic Resources, Kochi, under the National Bureau of Fish Genetic Resources (NBFGR), discovered two new freshwater fish species from the Western Ghats. These species are named Labeo uru and Labeo chekida, and they help resolve a 150-year-old confusion over the identity of Labeo nigrescens, first described in 1870. Labeo uru, named after the traditional wooden dhow because of its sail-like fins, was found in the Chandragiri river. Labeo chekida, locally called kaka chekida for its dark body, was discovered in the Chalakudy river. The study confirmed Labeo nigrescens as a separate species, noted for its kinked lateral line and unique scale patterns. These findings highlight the Western Ghats as a major biodiversity hotspot, with rivers possibly hosting many undiscovered species.

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Recently, at least 20 red-crowned roofed turtles were re-introduced into the river Ganga in Uttar Pradesh to boost their population. The red-crowned roofed turtle, also known as the Bengal roof turtle, is native to India, Bangladesh, and Nepal. In India, the National Chambal River Gharial Sanctuary is currently the only area with a good population of this species. It is a freshwater turtle that lives in deep flowing rivers and uses land areas for nesting. Its conservation status is Critically Endangered under the International Union for Conservation of Nature (IUCN) and it is listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

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Scientists are closely watching the Axial Seamount as it is expected to erupt for the first time in ten years. Axial Seamount is an underwater shield volcano located about 300 miles off the coast of Oregon, United States, in the Pacific Ocean. It has a large caldera at its summit and rises to a depth of 1,400 meters below sea level. The volcano was formed by a hot spot, where molten material from Earth’s mantle rises into the crust. It lies on the Juan de Fuca Ridge, the tectonic boundary between the Pacific and Juan de Fuca plates. It features hydrothermal vents, which are underwater hot springs that release mineral-rich plumes heated by magma.

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A Rs 1,500-crore project to restore a 44-kilometre stretch of the Adyar River has been stalled since 2023. The Adyar River starts near Chembarambakkam Lake in Kanchipuram district, Tamil Nadu. It is one of three rivers flowing through Chennai and joins the Bay of Bengal at the Adyar Estuary. The estuary covers about 300 acres and was declared a protected wildlife reserve in 1987. The river is 42.5 kilometres long and supports Chennai’s estuarine ecosystem. The Adyar Creek near its mouth carries tidal water back to the sea. The river drains water from 200 tanks, lakes, streams, and rainwater over an 860 square kilometre area. Unfortunately, much city waste flows into the river, causing pollution.

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The Blyde Rondavel Flat Gecko was rediscovered in the Blyde River Canyon, Mpumalanga Province, South Africa, after being unseen for 34 years. This flat-bodied lizard grows up to 8–9 cm and is adapted to live on cliffs and rocky outcrops, making it hard to spot. It was first discovered in 1991, but no sightings since then led to fears of extinction or doubts about it being a distinct species. The International Union for Conservation of Nature (IUCN) had listed it as “Data Deficient” due to lack of data. The Endangered Wildlife Trust (EWT) confirmed its rediscovery during a special expedition to a remote rocky area. This gecko is the fifth lost species rediscovered by the Endangered Wildlife Trust in recent years, after a dune mole, a butterfly, a lizard, and a frog.

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A new species of cave-dwelling fish named Schistura densiclava was discovered by Gauhati University’s Department of Zoology in Meghalaya. It was found in Krem Mawjymbuina, a limestone cave near Mawjymbuin village in East Khasi Hills district. The cave is deep, seasonally accessible, surrounded by dense forest, and untouched by tourism, keeping it pristine. This discovery raises the number of known cave-associated fish in Meghalaya to six. Unlike typical cave fish, Schistura densiclava has working eyes and bright body colours, showing it is a troglophile, meaning it can live inside and outside caves. It belongs to the loach family called Nemacheilidae and thrives in cool, low-light cave streams.