Category Environment

More than 70 species of mushrooms are bioluminescent. Some of them light up only at night. As the temperature drops when the sun sets, the fungi begin to glow. Scientists believe fungi such as mushrooms, glow in order to attract insects. Insects are drawn to the mushrooms, which crawl around them. They pick up the spores of the fungi and help spread them. Fungal spores are microscopic biological particles that allow fungi to reproduce- what seeds are for plants, spores are for fungi. The light of fungi ranges from blue to green and yellow, depending on the species.

Scientists went foraging for the glow-in-the-dark mushrooms in Brazil and Vietnam. Back in the lab, reports Becker, they crushed the mushrooms to make a slurry filled with luciferins. Then they isolated the luciferin and studied it, capturing its chemical structure and experimenting with its ability to fuel those flourescent colors.

Not only does the team now know that the mushrooms are fueled by their own kind of luciferin, but they also figured out that the enzyme that combines with the chemical to trigger light could be what they call “promiscuous.”

That means that the enzyme might be able to interact with different luciferins—and produce even more shades of that pretty glow. And that suggests that when it comes to these magical mushrooms, there’s even more to discover.

 

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Sunlight does not penetrate 200 ft below the ocean’s surface, so the deep sea is essentially a cold, dark place. But if you dive underwater and go deep down, you may witness a blue-green glow here or a ghostly flicker there. And if you are lucky or a ghostly flicker there. And if you are lucky enough, you may witness lightshows of red, green, and blue. Where are these lights coming from? From marine organisms. This phenomenon of emitting light due to a chemical reaction within a living organism is called bioluminescence.

Shining stars

Though marine bioluminescent organisms live throughout the water column, from the surface to the seafloor and from near the coast to the open ocean, they are extremely common in the deep sea. As many as 90% of all the organisms in the deep sea are bioluminescent. Its the norm there, say scientists. Some of the bioluminescent marine organisms include fish, jellyfish, bacteria, algae, marine worms, crustaceans (shrimp, lobster, krill etc.), sharks and cephalopad (octopus, squid, cuttelfish). In fish alone, there are about 1,500 known species that emit light.

Thought rare, bioluminescence be witnessed among a few terrestrial organisms as well. They include firefiles, land snails, glow worms and some types of fungi. Some forms of bioluminescnence are brighter or exist only at night.

Chemical reaction

How is the light produced? The light is produced by a chemical reaction involving light-emitting molecule luciferin and light-emitting enzyme luciderase found in the organisms. When luciferase interacts with luciferin in the presence of oxygen, light is produced.

But not all bioluminescent reaction involve luciferase. Some involve a chemical called photoprotein instead of luciferase.

Some creatures produce their own light while others such as squid foster a symbiotic relationship with certain bacteria that live on the organism and emit light to help the host. (The host organisms provide these bacteria a safe home and sufficient nutrition. In exchange, the hosts use light produced by the bacteria for camouflage, prey or mate attraction.)

Colour choice

Most marine organisms emit light in the blue-green part of the visible light spectrum. These colours are more easily visible in the deep ocean. Land organisms also exhibit blue-green bioluminescence, but there are those that glow yellow such as fireflies.

A few organisms can glow in more than one colour. The head of the railroad worm(a larvae of a beetle species) glows red while its body glows green. The bioluminescent colour is a result of the arrangement of luciferin molecules and the type of the luciferase enzyme.

What the purpose?

Bioluminescent organisms often light up in response to an attack or a disturbance such as touch, waves or the passing of a boat (e.g: dinoflagellate); some use it to hunt prey (anglerfish has a fleshy growth on its head, which, when lit up, looks like a fatty, juicy worm. The fish uses it to attract prey); to find mate (the female of Bolitaena pygmaea), a deep-sea octopus species, lights up around the mouth to attract mate) and to communicate (scientists think the lanternshark uses bioluminescence to communicate to other members of its species). Some use bioluminescence as a defence tactic to surprise or confuse a predator (many types of jellyfish and squids) or to camouflage (hatchet fish and many shark species produce light to match their background).

 

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California has been in the news for all the wrong reasons. On the one side, this U.S. State has been fighting a series of wildfires that have destroyed acres of forests and displaced thousands of people. On the other, it’s facing threat from the explosion of a marine species called the purple sea urchin. These urchins have chomped off 90% of the bull kelps along the coastline of California and neighbouring State Oregon, putting the entire coastal ecosystem out of whack.

Kelps are a type of a large brown seaweed that grow in shallow, nutrient-rich saltwater, near coastal fronts around the world. They offer shelter to a host of sea creatures. The coastal water of northern California was once home to a dense coverage of kelps. But today, they have been replaced by purple sea urchins. The vast stretch of the seafloor is barren and is dotted with nothing but tens of millions of these spiny orbs.

Sea urchins are typically spiny, round creatures, inhabiting all oceans. They belong to the phylum Echinodermata – the same group or sea stars, sand dollars, sea lilies and sea cucumbers.

The purple sea urchin – Steongylocentrtus purpuratus – is voracious, kelp-eating species. They are particularly fond of bull kelps. They are native to California’s coast, and have traditionally been found in smaller numbers. But now, from California, the population of the sea urchins has spread to Oregon reef, where their count has been found to be 350 million – more than a 10,000 % increase since 2014. These millions and millions of sea urchins are eating away not just kelps but also anemones, the sponges, flesh red algae and even sand, say scientists.

Cascade of events

Sea water wasting

The trouble began in 2013, when a mysterious disease began to spread among starfish. Scientists are not sure what caused the diseases in sea stars. It wiped out tens of millions of the species. This included sunflower sea water, which is the only real predator of the purple urchin. With no predators to keep the population in check, the hitherto harmless purple sea urchins began to grow and multiply, eating everything in sight. Destruction of kelps, their primary source of food, left other creatures depended on it to starve and die. Meanwhile, purple sea urchins’ population grew 60-fold between 2014 and 2015.

Double whammy for kelps

The kelps had already been struggling because of warmer-than-usual waters in the Pacific Ocean. Warm waters are nutrient poor, and as a result, the kelp cannot grow high enough to reach the surface of the water for photosynthesis. The 2014 record-breaking heatwave and subsequent El Nino condition in 2015 fuelled their decline further.

Ecosystem collapses

As the kelps population declined, 96% of red abalone, a type of sea snail that feeds on kelp, died from starvation, by 2017. According to a study, red sea urchins, a meatier relative of purple urchins, are also declining due t lack of food kelps.

Fisheries affected

The devastation is also economic. Until recently, red abalone and red sea urchins supported a thriving commercial fishery in both California and Oregon. But the mass moralities of red abalone led to its closure in 2018. The commercial harvest of red sea urchins in California and Oregon also has taken an enormous hit.

Can kelps rebound?

• Bull kelp is one of the fastest-growing algae on Earth and if the cooler water temperatures return, the seaweed may be able to bounce back. But the excessive numbers of purple sea urchins will still pose a problem.
• The only way to restore the kelp is to remove the purple sea urchins. But to remove the ones in Oregon alone, it would take 15 to 20 years, by scientists. Without the kelps, purple sea urchins by themselves may decline. But again it could be a long wait.
• Conservationists suggest urchin farming as a solution to the problem. It involves physically removing large numbers of purple sea urchins from the seafloor to be flattened up in controlled environments for human consumption.
• However, even if the kelps rebound, it may take decades for the entire ecosystem to bounce back to its past glory.

 

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Seeking ti replace the 2006-version of the law, the Union Ministry of Environment, Forest and Climate Change unveiled the draft to the public in March 2020, a day before the COVID-19 lockdown was put in the place. The new draft has drawn criticism from environmentalists and experts across the country. They allege that many provisions in it are ‘anti-environment’ and ‘pro-industries’ and is diluting the very purpose of the EIA. While the government has denied their claims, it has assured to take into consideration the feedback submitted by the public to the Ministry on August 11. Here, we list four of the main contentions identified in the new draft.

Post-facto clearance

The EIA new draft 2020 allows post-facto clearance, which means that even if a project has come up without environment clearances, it could carry out operation and the developers can choose to obtain a clearance after the project is initiated. For instance, national highways expansion are exempted from obtaining prior environmental clearance. Critics say even if the environmental clearance for such project is rejected ultimately, the damage done to the environment would be irreplaceable.

Further, those units that have been already operating illegally without environmental clearance can now get clearance and become legal units by simply submitting a remedial plan and paying the prescribed penalty, though hefty.

Expemtion from EC

The draft has exempted almost 40 types of projects such as clay and sand extraction or digging wells or foundations of building, solar thermal power plants and common effluent treatment plants from prior EC.

Further, a mining project can now get environmental clearance for a period of up to 50 years in the beginning itself, which, in the 2006 version up to 30 years only.

The public consultation process will be weakened

The draft said public consultation is exempted for many projects, including modernisation of irrigation; building, construction and area development projects; inland waterways; expansion or widening of national highways and all projects concerning national defence and security or involving “other strategic considerations” as determined by the central government.

The new draft also suggests reducing the number of days within which the members of the public can submit their concerns. From 30 days, it has now been reduced to 20 days.

Reporting of violations

According to the new draft, the violations of environmental laws by any project can be reported by a government authority or the developer of the project themselves.

This means that the members of the general public (who are usually the affected) or environmental activists cannot flag a project for violating the norms.

 

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Scientists discovered a new species of marine creature in the deepest trench on Earth. In a normal scenario, this would have called for celebration. But this situation isn’t normal. Because the researchers also identified plastic in its body.

The amphipod is just two inches long and was caught at a depth of 20,000 feet in the Mariana Trench. The Mariana Trench in the Pacific Ocean is the deepest point on Earth’s surface, reaching more than 36,000 feet deep. Clearly, even this remote environment is not exempt from the impact of plastic pollution. The tiny creature had been found to have ingested tiny pieces of debris known as microplastics. The material they identified was polyethylene terephthalate (PET), common plastic widely used in food and drink packaging. To highlight the scale of marine plastic pollution crisis, researchers decided to name it Eurythenes plasticus. The creature is now one of the 240 known species to have been recorded ingesting plastic.

Plastic debris is now common throughout the world’s oceans. In fact, a 2015 study found that around eight million tones of the material enter the oceans every year. Once in water, this plastic can break down into smaller and smaller pieces, eventually becoming microplastics – frequently ingested by marine animals. Thousands of animals, from sea birds to whales, die every year from consuming or getting caught in plastic.

 Pollution in Alarming scale

• According to a 2017 study, humans have produced 18.2 trillion pounds of plastic since the 1950s. Only 9% of it has been recycled and another 12% has been burnt. A majority of the plastic ends up in landfills and the oceans. The debris is often carried by wind and rain into our drainage networks and eventually into the sea.
• A report released by Ellen MacArthur Foundation at the World Economic Forum in 2016 estimated that at least eight million tones of plastics leak into the ocean – this is equal to dumping the contents of one garbage truck into the ocean every minute. The report further says the ocean is expected to contain one tonne of plastic for every three tonnes of fish by 2025, and by 2025, there will be more plastic than fish by weight in the ocean.

What are microplastics?

Most plastic in the ocean break down into very small particles called microplastics and make their way into the system of marine animals. Plastic particles that are less than five mm long are called microplastics. Microplastics come from a variety of sources, and are of two types – one that are manufactured (microbeads) and the other that are derived from the breakdown of larger plastic debris. Besides water, microplastics have been found in soil and air.

How plastic affects marine ecosystem

Sea turtles and other marine creatures mistake plastics for food (such as jellyfish) and ingest them. This causes blockage in their digestive system, leading to their death. Studies have found that plastic pollution can also affect sea turtles’ reproductive system.
In sea birds, plastic ingestion reduces the storage volume of the stomach, causing starvation and death.
Besides ingestion, marine mammals get tangled up in plastic, leading to their death.
Plastic may also get transferred along the food chain – from fish to bigger fish or marine mammals and finally to human seafood consumers.

Invisible threat

Marine species also face the invisible threat of plastic-derived chemicals. It was long held that plastic broke down only at very high temperatures and over hundreds of years. A study in 2009 showed that some plastics decompose rapidly in the ocean, even within a year of the trash hitting the water. The degrading plastics also leach potentially toxic chemicals such as bisphenol A into the seas, possibly threatening ocean animals, and human, who ultimately consume some of these creatures.

• Direct toxicity of plastics comes from lead, cadmium and mercury added to them while manufacturing plastic products. These toxin s have been found in many fish in the ocean.
• When expanded polystyrene, used especially for making food containers, breaks down, the tiny polystyrene components start to sink, as they are heavier than water. Exposure to polystyrene can cause irritation of the skin, eyes and the upper respiratory tract in humans. Acute exposure may also result in gastrointestinal effects.
• Bisphenol A (BPA) has been shown to interfere with the reproductive systems of animals. In humans, even low doses of bisphenol A can impair immune function and cause cancer, obesity, diabetes and hyperactivity, among other problems.
• Diethylhexyl phthalate (DEHP) contained in some plastics, is also carcinogenic (cancer-causing).

 

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Locusts are large insects. They are special grasshoppers. They have big hind legs used for jumping. All grasshoppers (except the long-horned, ones) belong to the Acridoidea family, and the most important Locusts are all in the family Acrididae. Locusts can change their habits and, behaviour when they occur in large numbers their numbers rise they stay together in dense groups called, “swarms.” These are groups of adults. Locust groups are called “bands” when; they consist of the wingless young ones, commonly called ‘hoppers’. Locust swarms migrate over great distances, and, this behaviour differentiates them from other grasshoppers. When, locusts are in small numbers they live their individual lives like ordinary grasshoppers. These could be small groups that stay in one place. Some species of locusts are regarded as intermediate between grasshoppers that live alone and typical locusts that do not.

Locusts have the capacity to multiply rapidly and produce groups or swarms in special circumstances. Their population explosion can be started by unusual weather conditions or changes in land use. This is what happened this year. According to the UN, the heavy infestation this year can be traced back to cyclone season of 2018-19 that brought heavy rains to the Arabian Peninsula. This allowed at least three generations of “unprecedented breeding” and no one noticed it. Swarms have since spread out into South Asia and East Africa. David Phiri, a FAO regional, coordinator said that whew weather conditions are good for locust breeding, there is a high probability that the insects will continue to spawn rapidly. This year it may go on till April. Locusts have probably been man’s enemies ever since humans began to grow crops. The Old Testament (Bible) and the Koran mention the desert Locust. You can see carved, images of Locusts in Sixth Dynasty (2420-2270 BC) tombs at Saqqara in Egypt. Now, in countries like Somalia, Locusts can determine whether people will have sufficient food or starve. The damage they cause can be mild to very severe. This depends on whether the swarms are moving about quickly or whether they stay for several days in one area.

FAO describes the desert Locust, schistocerca gregaria, as the world’s “most dangerous migratory pest, with a, voracious appetite unmatched in the insect world.” Swarms can vary from, less than 1 sq km (0.38 square miles) to several, hundred. Each square kilometre can contain at Least 40 million insects, according to FAO. FAO’s Western Africa joint Locust control force was established, in 2016 and includes Mauritania, Algeria, Burkina Faso, Morocco, Niger, Senegal, Chad, Libya, and Mali.

 

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