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Category Environment

How do you control a swarm of locusts?

Controlling locust swarms is no easy task. The larger the swarms, the more difficult the task becomes.

  • At present, the primary method of controlling desert locust swarms and hopper bands is to use pesticides, which is applied in small concentrated doses by vehicle-mounted and aerial sprayers. (However, this led to environmental concerns).
  • Natural predators such as wasps, birds and reptiles may prove effective at keeping small swarms at bay.
  • Other strategies include catching them in nets, driving them away by burning tyres, collecting hoppers with catching machines, trapping them in duties, and other mechanical methods.
  • One of the most effective ways to avoid the devastating effects of locust players is to prevent them from happening in the first place. Early warning and preventative control strategies are in place in some places. Locust monitoring stations collect data on weather, ecological conditions and locust numbers, making forecasts of the timing and location of breeding.

 

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Which are the dreaded locusts?

  • The desert locust is potentially the most dangerous of the locusts because of the ability of swarms to fly rapidly across great distances. Plagues of the desert locust have threatened agricultural production in Africa, the Middle East and Asia for centuries.
  • During quiet periods (known as recessions) the desert locust is usually restricted to the semi-arid and arid deserts of Africa, the Near East and South-West Asia, inhabiting some 30 countries (including India) but during plagues, they may spread over an enormous area of nearly 30 million sq. km., extending over 60 countries.
  • According to the National Geographic, a single swarm of the desert locust can be 460 square miles in size and pack between 40 and 80 million individuals into less than half-a-square mile. Each locust can eat its weight in plants each day, so a swarm of such size would eat 423 million pounds of plants every day.
  • The desert locust flies with the wind and swarms can travel from about five to 130 km or more in a day. Solitary adults usually fly at night whereas gregarious adults fly during the day. The locust can live between three and six months, and there is a 10- to 16-fold increase in locust numbers from one generation to the next.

When conditions are right

  • The desert locust reproduces and increases in numbers, when conditions are favourable. It needs moist, sandy soil to lay eggs and fresh vegetation for hoppers (nymphs) to grow into adults. A good monsoon is therefore a cause for concern.
  • Females lay about 95 to 158 eggs in an egg pod in soft soils at a depth of 10 to 15 cm below the surface. The location needs to be at the night temperature and right degree of dampness.
  • Thought it’s still a mystery what triggers solitary insects to become gregarious, scientists have theorised that a primary cause of the switch happens when individuals regularly touch others on the hind legs within populations. When population starts to build up following a period of drought, individuals concentrate in an environment while foraging. As young insects get more crowded, the close physical contact causes the insects’ hind legs to bump against one another. This triggers a change in behaviour, they say.

 

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Why was the Basel Convention created?

The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal was adopted in 1989 and it came into force in 1992. The convention aims to protect human health and the environment against the adverse effects resulting from the generation, transboundary movements and management of hazardous waste and other waste.

In May 2019, 187 countries agreed to amend the Basel Convention to subject shipments of scrap plastic to tighter controls and greater transparency. Set to come into effect in 2021, this amendment would prohibit nations from exporting hazardous plastic waste to other countries.

 

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Why countries urged to cut down on plastic?

The Southeast Asian importers became swamped with waste posing significant threat to the environment. The sheer quantity of imported scrap not only overwhelmed ports, but also caused a sharp uptick in illegal recycling operations. Illegal recyclers dumped toxic wastewater into waterways and polluted the air with fumes from burning plastic.

These countries began to face backlash from the public and environmental groups, who used officials to permanently ban the import of plastic waste. This made countries send unwanted and contaminated waste back to the countries it came from and to impose new controls.

  • In 2018, Malaysia announced bans on imports of plastic scrap by 2021. Malaysia has revoked import permits and has been clamping down on illegal processing plants.
  • Thailand has temporarily prohibited plastic waste import.
  • Indonesia has restricted the import of non-recyclable waste and Vietnam will bar all imports of plastic scrap by 2025.
  • India announced that a ban on import of plastic waste would began in August, 2019.

 

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Why did China stop taking recycling?

China was the world’s biggest importer of scrap plastic, receiving close to half of the world’s global plastic waste for three decades. But serve pollution concerns prompted the country to impose a ban on plastic waste import abruptly in January 2018. This shook up the global garbage/scrap trade. With the primary importer of plastic waste out of the market, exporting countries began sending increasing volumes of scrap to Southeast Asia, with Malaysia emerging as the number one importer. Vietnam, Thailand and Indonesia also picked up a lot of the slack. Malaysia’s imports rose five-fold and the Philippines’, three-fold.

The recycling crisis triggered by China’s ban could have an upside, experts say, if it leads to better solutions for managing the world’s waste, such as expanding processing capacities in North America and Europe, and spurring manufacturers to make their products more easily recyclable. Above all, experts say it should be a wake-up call to the world on the need to sharply cut down on single-use plastics.

Over the coming decade, as many as 111 million tons of plastics will have to find a new place to be processed or otherwise disposed of as a result of China’s ban, according to Brooks and University of Georgia engineering professor Jenna Jambeck. However, the places trying to take up some of the slack in 2018 tended to be lower-income countries, primarily in Southeast Asia, many of which lack the infrastructure to properly handle recyclables. Many of those countries were quickly overwhelmed by the volume and have also now cut back on imports.

 

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Why some countries are shipping back plastic waste?

For many years now, wealthier nations have been shipping their waste including paper, plastic, metal and electronic items, to developing countries, which recycle them and use them as raw material in their manufacturing businesses. For the former, it’s a cheap way to dispose of their waste, and for the latter, waste is a valuable source of income. But in recent months, the global waste trade has been facing a crisis. A growing number of countries are demanding that nations take back their plastic waste. Malaysia, the Philippines and Indonesia have started to send contaminated waste back to where it came from. Returning 42 shipping containers of illegally imported plastic waste to the U.K., Malaysia’s Environment Minister Yeo Bee Yin announced last month that Malaysia would take steps to ensure it does not become the garbage dump of the world. In 2019, the Philippines shipped back 69 containers of plastic to Canada that it said was falsely labelled as recyclable in 2013 and 2014.

Global trade in plastic waste is a big business. According to an estimate, from 1988 to 2016, the top 10 plastic waste exporters shipped 168 million tonnes, most of it to China. Exporting is seen as a cheaper option than sorting, cleaning, recycling or reusing it locally.

In developing countries on the other hand, recyclers line up to buy this waste and turn it into new products.

In the recent past, countries found themselves dealing with huge volumes of waste they are ill-prepared to handle. Such waste also contains a variety of materials, chemical additives and dyes that make it next to impossible to recycle. Workers who process these shipments are often exposed to hazardous chemicals. Further, the plastic that cannot be recycled is disposed of in incinerators, landfills, thereby polluting the air, land and sea. Worries about receiving such waste have forced countries to act.

The Exporters

  • Garbage is exported from about a dozen developed countries, including the U.S., Canada, France, Belgium, Germany, Spain, the Netherlands and the U.K., according to Greenpeace.
  • The European Union is the largest exporter of plastic waste, with the U.S. leading as the top exporter for a single country.

The Importers

  • The list predominantly includes Asia countries such as China, Malaysia, India, Indonesia, Vietnam, Thailand, the Philippines, South Korea, Taiwan, and Hong Kong. They import some form of waste or the other.
  • About 1,21,000 metric tonnes of plastic waste is imported to India.
  • Interestingly, some developed countries too import plastic waste. They include Germany, the U.S., Italy, Canada, Sweden, France, the U.K., the Netherlands and Belgium.

 

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HOW DO THE MAIN ECOSYSTEMS DIFFER?

Terrestrial ecosystems are many because there are so many different sorts of places on Earth. Some of the most common terrestrial ecosystems that are found are the following:

Rainforests – Rainforests usually have extremely dense ecosystems because there are so many different types of animals all living in a very small area.

Tundra – As mentioned above, tundra usually have relatively simple ecosystems because of the limited amount of life that can be supported in these harsh conditions.

Deserts – Quite the opposite of tundra in many ways, but still harsh, more animals live in the extreme heat than live in the extreme cold of Antarctica, for instance.

Savannas – These differ from deserts because of the amount of rain that they get each year. Whereas deserts get only a tiny amount of precipitation every tea, savannas tend to be a bit wetter which is better for supporting more life.

Forests – There are many different types of forests all over the world including deciduous forests and coniferous forests. These can support a lot of life and can have very complex ecosystems.

Grasslands – Grasslands support a wide variety of life and can have very complex and involved ecosystems.

Since there are so many different types of terrestrial ecosystems, it can be difficult to make generalizations that cover them all.

Because terrestrial ecosystems are so diverse, it is difficult to make generalizations about them. However, a few things are true almost all of the time. For instance, most contain herbivores that eat plants (that get their sustenance from the sun and the soil) and all have carnivores that eat herbivores and other carnivores. Some places, such the poles, contain mainly carnivores because not plant life grows. A lot of animals and plants that grow and live in terrestrial ecosystems also interact with freshwater and sometimes even ocean ecosystems.

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WHERE ARE THE MAIN ECOSYSTEMS OF THE WORLD?

The map below shows the main ways in which the Earth can be divided into different ecosystems. These are based mainly on the kind of plants that grow in an area, as all other living things rely directly or indirectly on plants for their food. Of course, there are many smaller ecosystems within these broad divisions.

An ecosystem consists of all the living and non-living things in a specific natural setting. Plants, animals, insects, microorganisms, rocks, soil, water and sunlight are major components of many ecosystems. All types of ecosystems fall into one of two categories: terrestrial or aquatic. Terrestrial ecosystems are land-based, while aquatic are water-based. The major types of ecosystems are forests, grasslands, deserts, tundra, freshwater and marine. The word “biome” may also be used to describe terrestrial ecosystems which extend across a large geographic area, such as tundra. Keep in mind, however, that within any ecosystem, specific features vary widely – for instance, an oceanic ecosystem in the Caribbean Sea will contain vastly different species than an oceanic ecosystem in the Gulf of Alaska.

Forest Ecosystems

Forest ecosystems are classified according to their climate type as tropical, temperate or boreal. In the tropics, rainforest ecosystems contain more diverse flora and fauna than ecosystems in any other region on earth. In these warm, moisture-laden environments, trees grow tall and foliage is lush and dense, with species inhabiting the forest floor all the way up to the canopy. In temperate zones, forest ecosystems may be deciduous, coniferous or oftentimes a mixture of both, in which some trees shed their leaves each fall, while others remain evergreen year-round. In the far north, just south of the Arctic, boreal forests – also known as taiga – feature abundant coniferous trees.

Grassland Ecosystems

Different types of grassland ecosystems can be found in prairies, savannas and steppes. Grassland ecosystems are typically found in tropical or temperate regions, although they can exist in colder areas as well, as is the case with the well-known Siberian steppe. Grasslands share the common climactic characteristic of semi-aridity. Trees are sparse or nonexistent, but flowers may be interspersed with the grasses. Grasslands provide an ideal environment for grazing animals.

Desert Ecosystems

The common defining feature among desert ecosystems is low precipitation, generally less than 25 centimeters, or 10 inches, per year. Not all deserts are hot – desert ecosystems can exist from the tropics to the arctic, but regardless of latitude, deserts are often windy. Some deserts contain sand dunes, while others feature mostly rock. Vegetation is sparse or nonexistent, and any animal species, such as insects, reptiles and birds, must be highly adapted to the dry conditions.

Tundra Ecosystems

As with deserts, a harsh environment characterizes ecosystems in the tundra. In the snow-covered, windswept, treeless tundra, the soil may be frozen year-round, a condition known as permafrost. During the brief spring and summer, snows melt, producing shallow ponds which attract migrating waterfowl. Lichens and small flowers may become visible during this time of year. The term “tundra” most commonly denotes polar areas, but at lower latitudes, tundra-like communities known as alpine tundra may be found at high elevations.

Freshwater Ecosystems

Freshwater ecosystems can be found in streams, rivers, springs, ponds, lakes, bogs and freshwater swamps. They are subdivided into two classes: those in which the water is nearly stationary, such as ponds, and those in which the water flows, such as creeks. Freshwater ecosystems are home to more than just fish: algae, plankton, insects, amphibians and underwater plants also inhabit them.

Marine Ecosystems

Marine ecosystems differ from freshwater ecosystems in that they contain saltwater, which usually supports different types of species than does freshwater. Marine ecosystems are the most abundant types of ecosystems in the word. They encompass not only the ocean floor and surface but also tidal zones, estuaries, salt marshes and saltwater swamps, mangroves and coral reefs.

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Where are most bushfires in Australia?

Bushfires happen almost every year across the island-nation of Australia. However, this time around, it has been one of the worst-ever. What began in September 2019 has continued well into 2020. It has claimed more than 25 lives while reducing millions of acres to ash. And New South Wales was hit the hardest – in this State alone, more than half-a-billion creatures, including mammals, birds and reptiles, are feared to have perished. There are reports that thousands of kangaroos and koalas have been consumed by the fire across the country. The last few decades have seen an increase in the number of bushfires, and may be attributed to global warming. As for Australia, the bushfires season seems to be beginning earlier and lasting longer. In a chilling revelation, the U.K. scientists have said that the recent fires in Australia are assign of what the world will go through as temperatures increase.

 

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Why tiger population was reduced rapidly in India?

A telling identity of our planet’s biodiversity, the tiger is also a keystone species. And its population the world over, and especially in India, has been of particular concern. However, July 2019 brought with it some comforting news. The findings of the Tiger census, conducted in our country once in every four years, showed that the tiger population had increased from 2,226 in 2014 to 2,967 in 2018. With that, India is estimated to be home to around 70% of the world’s tigers. Following an alarming decrease in the tiger population since the early 20th Century, the government had put in place stringent laws in the 1970s to protect the national animals, and this seems to have been paying off over the last decade or two. However, human-animal conflicts continue, and conservationists have repeatedly called for an increase in protected areas for the tiger.

 

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