My Science School

World Paper Bag Day is observed on July 12 every year to spread awareness about plastic pollution and encourage the use of environment-friendly alternatives. Use of paper bags, which are easily recyclable, will help reduce plastic waste that takes years to decompose, causing environment pollution.

Remember the 3 'R's? We know this mantra of Reduce', 'Reuse and Recycle can help us adhere to a sustainable lifestyle. It's also our trump card to save the Earth. What if we told you that there is also another lifestyle choice you could make to help the earth breathe, reduce your carbon footprint and regulate the usage of plastic.

Does it come as a surprise that the humble Paper Bag has a day of its own

The first machine

Not much literature is available as to how Paper Bag Day came to be or who started it. But the day gets marked with a flurry of programmes to promote the usage of paper bags. But there is a lot of drama and story behind this bag and how it came to be. Did you know that it was in 1852 that the first paper bag machine was established? This was by American inventor Francis Wolle who patented the first paper bag-making machine. Wolle who was also a priest called it the 'Machine for Making Bags of Paper.

Later, inventor Margaret E. Knight came up with a machine that could fashion out flat-bottomed paper bags. She patented this in 1870. This invention made a lot of difference enabling the production of flat-bottomed paper bags that could carry groceries.

It is interesting to note that the inventions didn't stop here! In 1883, another patent was granted. And this was to Charles Stilwell who created the S.O.S bag aka Self Opening Sack. Stilwell named it so because the bags could stand on their own without anyone's assistance while it was being loaded.

An alternative to plastic

Much has been talked about plastic and single-use carry bags and their detrimental environmental effects. Yet we still find it being used abundantly in marketplaces. People still depend on it out of convenience.

There is an organic solution to tackle this. Paper bags! One can easily create these bags using recycled paper. You must have seen that newspapers are quite often used for making paper bags.

Make your own bags

So, let's pledge never to use plastic bags and shift to sustainable alternatives such as paper bags or cloth bags.

And try making your own paper bag! Trust us, you will enjoy the process. You can introduce your fellow mates to this bag that can do so much and initiate them to the new craft of making paper bags. Make this sustainable lifestyle choice and be the change!

QUICK FACTS

According to estimates, 100 trillion plastic bags are used worldwide every year.

About 18 billion pounds of plastic find their way into the ocean every year, proving to be life-threatening to marine life. And this plastic stays in the ocean.

According to statistics, over 40% of the plastic produced gets used only once. And they get discarded, ending up as refuse on the Earth, taking years to disintegrate.

In the case of single-use plastic bags, it could take hundreds of years to disintegrate and get turned into microplastics, polluting the environment further. The plastic that we use today could easily stay on even after our journey.

SAY 'NO' TO PLASTIC BECAUSE...

It takes centuries to decompose.

It contains many chemicals that pollute the soil and the environment.

It affects food chains; harms water resources, has led to the unnatural death of animals species on land and sea. It is expensive to recycle.

Picture Credit : Google 

Beaches are much more than just recreation - they are integral to the ecosystem and for livelihood. There is thus, a need to preserve them.

Beaches are amazing wonders of nature. But they are not just spaces for recreational activities. They support an incredible diversity of marine life and the livelihood of fisherfolk. They act as a natural barrier between the land and the sea protecting coastal areas from large waves during a storm. Without this barrier, coastal land would be infertile, courtesy, the sea's salty water.

India has a long coastline of over 7,500 km which includes both sides of the Indian peninsula and the islands. But, did you know that at many places along the coast, the sandy shoreline has been disappearing slowly? As much as 33 per cent of the coastline has been lost in 26 years between 1990 and 2016 alone. This phenomenon, known as coastal erosion is natural and human-induced.

Coasts undergo constant changes due to natural factors, such as rivers flowing into the sea, sediment deposition, tides, storms, tsunamis and more. However, it is human activity that has put our beaches in peril today.

Threatened existence

A beach is formed when a river deposits large amounts of sediment as it drains into the sea. Dams, built along the course of rivers, have disturbed this natural flow of sediment to the coast. Many ports and fishing harbours dotting the coastline have changed the natural pattern of sand distribution along the coast. Sediments have to be removed from time-to-time to maintain ports. But, they are rarely ever replenished, leading to beach erosion.

Rampant sand mining is a huge contributor to coastal erosion. Sand is a common raw material for construction activities, and its growing demand has spawned sand mafias, which routinely take away truckloads of sand from beaches. Then, mangrove forests hemming the shoreline, that bind the sand together and prevent erosion, are being destroyed for building homes factories, and for commercial activities like aquaculture.

Global warming, over the past several decades, has caused glaciers to melt, leading to a rise in sea levels. Rising seas have been slowly engulfing coastal areas. Due to the rapidly warming Indian Ocean, cyclones are increasing in number and intensity on India's east and west coasts. Severe cyclones cause changes to the coastal geography. Added to this are many illegal constructions that have encroached upon the coastline despite a ban. This has not only endangered coastal ecosystems but also caused large-scale beach erosion.

In the past two decades, the sea has swallowed up large stretches of our coastline, destroying hundreds of homes and forcing families into temporary shelters. With no beach to stop the sea from flooding villages and towns, the govemment built high stone walls to keep the waves at bay. But sea walls seem to have caused more harm than good.

Erosion during the monsoon is natural, but after the rains, the beach gets restored as the sediments that are washed away are returned to the beach But stone walls block this natural movement of sand. They also redirect the waves and cause another area along the coast to erode. Moreover, sea walls block the easy access of fishermen to the sea. In Kerala, over 65 per cent of the coast is now lined with stone walls instead of sand.

Beach restoration

Until 1989, Puducherry had a beautiful beach drawing thousands of tourists each year. It began to erode soon after the construction of a harbour, and disappeared completely within a few years. After unsuccessful attempts to contain the sea with stone walls, Puducherry finally adopted a sustainable plan to restore the beach. A triangular-shaped artificial reef, submerged into the sea, has been able to partially restore it within a year.

Odisha has installed geotextile tubes at Pentha, a small coastal hamlet in Kendrapara district. These tubes acted as an effective barrier and protected the coast during the cyclones that battered the state in the last decade. The beach has been restored here as well.

Picture Credit : Google 

So much of our oceans is still unexplored and remains a mystery. In fact, it is safe to presume we know more about the surface of Mars than about Earth's seafloors! But whatever  we little know of life in ocean depths is intriguing, fascinating, and incredible. The deep oceans are low on sunlight and plants but high on pressure, and yet, several creatures call this space home. Here's a glimpse of how they have adapted to life in unforgiving conditions.

Colours that help

 Since they dwell in open waters without plants or rocks to hide under to safeguard themselves from predators, many creatures benefit from disguise. Some of them are red. rendering them difficult to spot since red light does not penetrate those depths. Some others are transparent, again tough to spot. Many others are bioluminescent, a good tool to confuse predators.

Heard of sea snow?

Since ocean depths hardly have any plant, finding "live meal" is a tough task. Apparently, the duration between two live meals can be even up to three weeks for a marine creature! That's where marine snow or sea snow comes into play. When no live meal is available, the next best thing to turn to is the dead. Organic particles from the surface waters - disintegrated bodies of animals and plants, mingling with fecal matter-drift down in what is known as "marine snow".

What is chemosynthesis?

At the cracks between oceanic plates are hydrothermal vents - these are the hot springs on the ocean floor. These vents send out chemical compounds such as hydrogen sulphide. These chemical compounds are used for preparing food - much like sunlight is used in photosynthesis. This process used by microorganisms such as bacteria to create food (such as glucose), is called chemosynthesis.

Though humans still don't have a complete understanding of ocean depths, we're definitely leaving our mark there- and, sadly, not in a good way. With global warming, over-fishing, and pollution, we're changing the composition of the oceans they are acidifying, and hosting crustaceans with microplastics, as far deep as the Mariana Trench, the deepest location on Earth.

Picture Credit : Google 

It's inevitable that often its climate change that makes global headlines. For years, experts have been cautioning us about the impending doom of our planet if we do not mend our ways. Among the suggestions to save Earth is the expansion of green cover. But studies point to the fact that simply expanding green cover alone may not really rescue us from the dire situation we find ourselves in. Here's why. It is an established fact that forests take in large quantities of carbon dioxide from the atmosphere. So it would make sense to increase such areas to tackle the growing carbon dioxide content in the atmosphere. But it is important to note that due to global warming, there are increasing instances of wildfires and drought globally, killing off several trees. Such trees, dying in large numbers, are adding to the carbon in the atmosphere.

Further, it is assumed that more carbon dioxide for a tree translates to greater growth due to photosynthesis. However, a study has shown that rather than photosynthesis it's the cell division that drives the growth of trees. And this process is severely affected by climate change impact such as drought.

Such studies appear to point to the fact that rather than only trying to increase forest areas for carbon offset, it is perhaps more urgent, pertinent, and wiser to protect what exists already. This calls for cutting down on emissions. thus bringing down instances of forests being lost to wildfires, drought, and tree-attacking insects that thrive in a warmer world.

Picture Credit : Google 

A dip in the waters in the Hirsholm islets off the northern shores of Denmark is like diving into a giant aquarium. Amidst the dazzling colours of its vibrant marine life, tiny bubbles from the seabed soar to the surface like clear blobs. The unique phenomenon is caused by the presence of methane gas. The gas was probably formed due to the microbial decomposition of plants deposited thousands of years ago under the sea. As the gas seeped up through funnels in the floor, chemical reaction with underwater microbes hardened the sand particles into sandstone structures. Water currents washed away the surrounding loose sand, leaving behind solid stone columns, arches and slabs, which became thriving hubs of plant and animal life. The methane constantly bubbles out through vents in these columns, resembling air bubbles in a fish tank. The site is an important centre of marine biology.

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A type of algae, kelp is crucial for thriving ecosystems the world over. However, kelp forests are shrinking. But, why? Let's find out

Most types of seaweed or marine algae grow along the coasts in shallow waters, where they can attach themselves to rocks, shells, or the sea floor. A root-like part called holdfast anchors them firmly and prevents them being washed away by strong waves or currents. A soft, flexible stem-like frond with outgrowths similar to leaves emerges from the holdfast. Though they carry out photosynthesis, algae are not plants as they don't have true roots, stems, leaves, or flowers. Marine algae can be green, brown, or red in colour. Red algae are delicate and feathery and prefer warm tropical seas. Small green algae are found everywhere in shallow waters. Brown algae called giant kelp grow in cool waters at depths ranging from 15 to 40 mt.

Extraordinary ecosystem

A kelp forest is one of the most valuable and productive: ecosystems on Earth. Kelp forests are found all over the world-the west coasts of North and South America, the southern tip of Africa and Australia, and off islands near Antarctica. In North America, kelp forests are found on the Pacific Coast from Alaska to California. A forest of kelp is home to a variety of creatures. They live and forage for food among its broad blades. The kelp provides shelter not only from predators. but also from storms. Mammals and birds that thrive in kelp forests include seals, sea lions, whales, sea otters, gulls, terms, egrets, and herons. Sea otters have an especially beneficial bond with kelp. Mother otters wrap their babies in kelp to keep them from drifting away while they go hunting. Adult otters also find the dense kelp canopies a secure place to snooze. The otters return the favour by eating sea urchins that dine on kelp. Kelp forests can shoot up in no time, growing up to 30 cm a day. Some species attain heights of over 45 mt!

Kelp farming is a big part of the billion-dollar global seaweed-farming industry. Kelp renders sea water less acidic. This enables kelp farmers to raise shellfish, which require low acidity. Kelp and mussels are grown on floating ropes, which also support baskets of scallops and oysters. One kelp farm can produce 40 metric tonnes of kelp and a million shellfish per hectare per year! As with other species of seaweed, kelp is used in many products,) including shampoos and toothpastes, as well as a wide range of foods such as salad dressings, puddings, cakes, dairy products, and ice cream. It is also employed in pharmaceuticals and in the manufacture of fireproof and waterproof textiles.

Urchin attack

The waters off the coast of northern California are home to lush forests of bull kelp. Since 2013, the population of purple sea urchins that feast on the kelp, has exploded, destroying almost 90 % of the kelp forest. Sea stars prey on purple urchins and keep their numbers in check. However, a mysterious disease killed off huge numbers of sea stars, leaving sea urchins to thrive. Sea snails (called red abalone) and red sea urchins, both of which are raised for meat and feed on bull kelp, died from starvation. Commercial red sea urchin and red abalone fisheries located on America's northwestern coast have closed down as a result.

Fact file

• Kelp forests are the ocean's lungs just as trees are the Earth's lungs. They absorb carbon dioxide and give out oxygen.

• Warming seas along the Australian coast have wiped out huge swathes of kelp forest.

•Extremely hot weather is harmful to kelp forests. Strong storms can wipe out large areas by uprooting the plants from the sea floor.

• There are 18 species of edible kelp, including kombu widely used in Japanese cuisine.

•Kelp is rich in calcium and Vitamin K.

Picture Credit : Google 

An unplanned, uncontrolled fire that burns in a natural area such as a forest, grassland, or prairie, wildfires can happen anywhere at any time. Likely caused by human activity or natural phenomenon like lightning, it is not known as to how over half of the recorded wildfires began. Even though wildfires keep the ecosystem healthy and are even essential for the continued survival of certain plant species, they also simultaneously impact weather and climate by releasing large amounts of carbon dioxide, carbon monoxide, and fine particulate matter into the atmosphere.

Wildfires can burn in vegetation located both in and above the soil. Ground fires typically ignite in soil thick with organic matter that can feed the flames, like plant roots. Ground fires can smolder for a long time—even an entire season—until conditions are right for them to grow to a surface or crown fire. Surface fires, on the other hand, burn in dead or dry vegetation that is lying or growing just above the ground. Parched grass or fallen leaves often fuel surface fires. Crown fires burn in the leaves and canopies of trees and shrubs.

Some regions, like the mixed conifer forests of California’s Sierra Nevada mountain range, can be affected by different types of wildfires. Sierra Nevada forest fires often include both crown and surface spots.

Wildfires can start with a natural occurrence—such as a lightning strike—or a human-made spark. However, it is often the weather conditions that determine how much a wildfire grows. Wind, high temperatures, and little rainfall can all leave trees, shrubs, fallen leaves, and limbs dried out and primed to fuel a fire. Topography plays a big part too: flames burn uphill faster than they burn downhill.

Wildfires that burn near communities can become dangerous and even deadly if they grow out of control. For example, the 2018 Camp Fire in Butte County, California destroyed almost the entire town of Paradise; in total, 86 people died.

Still, wildfires are essential to the continued survival of some plant species. For example, some tree cones need to be heated before they open and release their seeds; chaparral plants, which include manzanita, chamise (Adenostoma fasciculatum), and scrub oak (Quercus berberidifolia), require fire before seeds will germinate. The leaves of these plants include a flammable resin that feeds fire, helping the plants to propagate. Plants such as these depend on wildfires in order to pass through a regular life cycle. Some plants require fire every few years, while others require fire just a few times a century for the species to continue.

Wildfires also help keep ecosystems healthy. They can kill insects and diseases that harm trees. By clearing scrub and underbrush, fires can make way for new grasses, herbs, and shrubs that provide food and habitat for animals and birds. At a low intensity, flames can clean up debris and underbrush on the forest floor, add nutrients to the soil, and open up space to let sunlight through to the ground. That sunlight can nourish smaller plants and give larger trees room to grow and flourish.

While many plants and animals need and benefit from wildfires, climate change has left some ecosystems more susceptible to flames, especially in the southwest United States. Warmer temperatures have intensified drought and dried out forests. The historic practice of putting out all fires also has caused an unnatural buildup of shrubs and debris, which can fuel larger and more intense blazes.

Credit : National geographic 

Picture Credit : Google 

 

An area of land that is either covered by water or saturated with water, wetlands are those areas where water covers the soil. While most scientists consider swamps, bogs, and marshes to be the three main kinds of wetlands, there are other types like peatlands, sloughs, and mires as well. Even though wetlands were seen as wastelands for most of history as they don't support development, it has since been realised that these are among the most valuable ecosystems on Earth. Governments began recognising the value of wetlands from the 1970s and laws have been put in place in parts of the world to protect wetlands.

Categories of Wetlands

Wetlands vary widely because of regional and local differences in soils, topography, climate, hydrology, water chemistry, vegetation and other factors, including human disturbance. Indeed, wetlands are found from the tundra to the tropics and on every continent except Antarctica. Two general categories of wetlands are recognized: coastal or tidal wetlands and inland or non-tidal wetlands.

Coastal/Tidal Wetlands

Coastal/tidal wetlands in the United States, as their name suggests, are found along the Atlantic, Pacific, Alaskan and Gulf coasts. They are closely linked to our nation's estuaries where sea water mixes with fresh water to form an environment of varying salinities. The salt water and the fluctuating water levels (due to tidal action) combine to create a rather difficult environment for most plants. Consequently, many shallow coastal areas are unvegetated mud flats or sand flats. Some plants, however, have successfully adapted to this environment. Certain grasses and grasslike plants that adapt to the saline conditions form the tidal salt marshes that are found along the Atlantic, Gulf, and Pacific coasts. Mangrove swamps, with salt-loving shrubs or trees, are common in tropical climates, such as in southern Florida and Puerto Rico. Some tidal freshwater wetlands form beyond the upper edges of tidal salt marshes where the influence of salt water ends.

Inland/Non-tidal Wetlands

Inland/non-tidal wetlands are most common on floodplains along rivers and streams (riparian wetlands), in isolated depressions surrounded by dry land (for example, playas, basins and "potholes"), along the margins of lakes and ponds, and in other low-lying areas where the groundwater intercepts the soil surface or where precipitation sufficiently saturates the soil (vernal pools and bogs). Inland wetlands include marshes and wet meadows dominated by herbaceous plants, swamps dominated by shrubs, and wooded swamps dominated by trees. Certain types of inland wetlands are common to particular regions of the country. 

Many of these wetlands are seasonal (they are dry one or more seasons every year), and, particularly in the arid and semiarid West, may be wet only periodically. The quantity of water present and the timing of its presence in part determine the functions of a wetland and its role in the environment. Even wetlands that appear dry at times for significant parts of the year -- such as vernal pools-- often provide critical habitat for wildlife adapted to breeding exclusively in these areas.

Credit : EPA 

Picture Credit : Google 

Waste management corresponds to the process of managing unwanted waste items. This includes collection, transport, processing or waste treatment, recycling, and disposal. Mainly done for waste produced by human activities, it started off in an effort to reduce their effect on human health or local aesthetics, but now addresses their effect on the natural world and environment at large as well. Wastes can be generated domestically, industrially, agriculturally, and commercially, among others, and its management can involve solid, liquid, or gaseous substances with different methods for each.

The aim of waste management is to reduce the dangerous effects of such waste on the environment and human health. A big part of waste management deals with municipal solid waste, which is created by industrial, commercial, and household activity.

Waste management practices are not uniform among countries (developed and developing nations); regions (urban and rural areas), and residential and industrial sectors can all take different approaches.

Proper management of waste is important for building sustainable and liveable cities, but it remains a challenge for many developing countries and cities. A report found that effective waste management is relatively expensive, usually comprising 20%–50% of municipal budgets. Operating this essential municipal service requires integrated systems that are efficient, sustainable, and socially supported. A large portion of waste management practices deal with municipal solid waste (MSW) which is the bulk of the waste that is created by household, industrial, and commercial activity. According to the Intergovernmental Panel on Climate Change (IPCC), municipal solid waste is expected to reach approximately 3.4 Gt by 2050; however, policies and lawmaking can reduce the amount of waste produced in different areas and cities of the world.[8] Measures of waste management include measures for integrated techno-economic mechanisms of a circular economy, effective disposal facilities, export and import control and optimal sustainable design of products that are produced.

In the first systematic review of the scientific evidence around global waste, its management and its impact on human health and life, authors concluded that about a fourth of all the municipal solid terrestrial waste is not collected and an additional fourth is mismanaged after collection, often being burned in open and uncontrolled fires – or close to one billion tons per year when combined. They also found that broad priority areas each lack a "high-quality research base", partly due to the absence of "substantial research funding", which motivated scientists often require. Electronic waste (ewaste) includes discarded computer monitors, motherboards, mobile phones and chargers, compact discs (CDs), headphones, television sets, air conditioners and refrigerators. According to the Global E-waste Monitor 2017, India generates ~ 2 million tonnes (Mte) of e-waste annually and ranks fifth among the e-waste producing countries, after the US, P.R. China, Japan and Germany.

Credit :  Wikipedia 

Picture Credit : Google