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Category Ecology

How hydroponic farming a sustainable solution?

We know that plants require sunlight, oxygen, water, and nutrients to grow. What about soil? Well, soil provides a hospitable place for a plant to anchor its root and serves as a source of water and nutrients needed for its growth. But if these two purposes are met by other means, plants would not need soil. That’s the basic principle behind hydroponic farming. By offering higher yield and using fewer resources, hydroponic technology may be able to mitigate impending food shortages from climate related events such as flooding, drought and high temperatures, scientists say. But how?

What is hydroponic farming?

As discussed earlier, hydroponics is the technique of growing plants without soil. In traditional gardening and fanning, plants get their nutrients from soil and additives such as compost, manure, and fertilizers. In hydroponic farming, plants get them from nutrient-fortified water.

Many hydroponic gardens are sprouting across the world, where crops and vegetables are produced in large quantities. The method is also catching up in urban areas in India, where households meet some of their vegetable needs this way.

Soil-less cultivation of vegetables was known to humankind since the ancient times. However, the interest in the technology was renewed in the 19th and the 20th centuries, when scientists such as Julius Sachs and W.E. Gericke studied the method extensively. Among other inventions, scientists also optimised the nutrient solution that are added to water for hydroponic farming. They include macronutrients (needed in large amounts) such as carbon phosphorous, hydrogen. nitrogen, oxygen, sulphur, potassium, magnesium, and calcium, and micronutrients (needed in tiny amounts but essential) such as zinc, nickel, boron, copper, iron, manganese, molybdenum, boron, and chlorine.

How it works

There are various methods of hydroponic farming. The most common method is to place the plants in a plastic trough, with their roots dipped directly into nutrient-rich solutions. Alternatively, the roots can be supported by a medium such as rockwool or peat moss, which acts as a sterile substitute for soil. These plants are watered with nutrient solution.

Hydroponic farming can be done indoors, with specific systems to control and monitor the pH level of water (pH level is the measure of how acidic / basic water is), temperature and the amount of light the plants receive. Some of the factors considered are:

Oxygen: In traditional farming, roots can get the oxygen needed for respiration from pockets of air in the soil. In hydroponic setup, the container has to be oxygenated using tools such as an air pump (similar to the ones in fish tank).

Root base: If not dipped in water, plants require root support in the form of materials such as vermiculite, perlite, peat moss, coconut fibre, and rockwool.

Light and temperature: The grower will have to be aware of the kind of light and temperature each species of plant requires to grow optimally.

Advantages

Saves space

  • Since soil is not involved in hydroponic fanning, there is no need to worry about land requirement. (This method is often adopted for vertical gardens.)
  • Moreover, roots don’t need spread because water and nutrients are delivered right to them. As a result hydroponic systems can grow more plants in the same amount of space as soil-based systems.

Faster growth

Since, hydroponically grown plants get their nutrients without much ado, they can divert more energy into the growth of leaves, stem, vegetables and fruits. This makes them grow faster. According to reports plants in hydroponic systems grow 30% to 50% faster than those grown in soil.

Anywhere, anytime

Hydroponics allows growers to produce food anywhere in the world, at any time of the year as climate and light can be controlled.

No pesticides

In a well-maintained, well-integrated indoor horticulture practice, the risks of pests is less, if not zero. Food grown this way are nutritionally superior.

Water conservation

Hydroponic systems use less water than traditional soil-based systems. This is because closed systems are not subject to the same rates of evaporation. Plus, the water used in hydroponic systems can be filtered, repopulated with nutrients, and fed back to plants. The same water can be used over and over again. According to reports, this method of faming reduces water dependence by as much as 90%.

Sustainable solution

The United Nations has estimated that the global human population will reach nearly 10 billion by 2050. In 2019, about 124 million people were estimated to have faced acute food shortages from climate related events such as flooding, irregular rains, drought, and high temperatures. With the rise in population and with farmers struggling to cope with demand, there is a global push for sustainable fanning. As hydroponics can help grow food in a controlled environment using less resources and offering healthier, higher yields, it is seen as a sustainable solution to food security.

Challenges

  • Setting up a hydroponic farm can be extremely expensive. Consider the cost of containers, pumps, lights, nutrients, and automated systems.
  • Since plants are grown in a controlled environment constant monitoring is required.
  • The process of hydroponic farming depends on a range of equipment that requires proper expertise
  • Air pump, lights, water pump, and the running of other appliances involve a high level of energy consumption.
  • In theory, you can grow any plant hydroponically but some do better than others. While tomatoes, strawberries, lettuces, and herbs do particularly well, root vegetables don’t take to hydroponics well. As hydroponic plants have much smaller root systems, they can’t always support themselves very well. Heavy fruiting plants may need elaborate forms of support.

 

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What are the golden rules for tree-planting?

To fight climate change, countries and organisations around the world have launched ambitious tree planting initiatives. India has pledged to get 33% of its geographical area under forest cover by 2022, Compared to the existing 24%. The United Nations launched the Bonn Challenge to bring 150 million hectares of degraded and deforested land into restoration by 2020 and 350 million by 2030. More than 74 governments, private associations and companies have pledged over 210 million hectares to the Challenge.

Trees are essential to life on Earth. They provide a home to plants and animals, soak up carbon dioxide, and provide food, fuel and medicines. Scientists have claimed that planting billions of trees could remove two-thirds of all the carbon dioxide created by human activity. Although such tree-planting initiatives could take a hundred years to be fully effective in addressing climate change, along the way they would reduce the consequences of the climate crisis – protecting soil from erosion, reducing the risk of flooding and providing habitats for a vast range of animals and plant species.

Tree planting is, indeed, a brilliant solution to tackle climate change and protect biodiversity. But the idea should not be to fill every available space with trees. Species need to be chosen carefully to ensure they grow well. Planting the right trees in the right place is crucial, say scientists. Otherwise, the entire exercise could become futile.

Scientists have recently proposed 10 golden rules for tree-planting, in a study published in the journal Global Change Biology. They say must be a top priority for all nations this decade. They are:

Protect existing forest: Stopping deforestation and protecting existing trees should also be part of the plan. Intact, old forests are better at soaking up carbon due to their complex structure. The old large trees are more resilient to fire and drought.
Make local people integral to the project: For successful outcomes in both forest protection and reforestation, it is vital to include local communities from the planning stage through to delivery and monitoring.
Maximise biodiversity recovery to meet multiple goals: Reforestation is a means to achieving various goals, typically climate-change mitigation, biodiversity conservation, socio-economic benefits (including food security), soil and hydrological stability and other ecosystem services.
Select appropriate areas for reforestation: Avoid previously non-forested lands and connect or expand existing forest, rather than using other natural habitats such as grasslands or wetlands.
Use natural regeneration wherever possible: Natural regeneration can be cheaper and more effective than tree planting. Work towards low intervention, including protection from further damage such as grazing or fire, and rewilding, which includes the selective reintroduction of missing fauna to restore natural processes.
Select the right species to maximize biodiversity: Where tree planting is needed, picking the right trees is crucial. Scientists advise a mixture of tree species naturally found in the local area, but avoiding trees that might become invasive.
Use resilient plant material: To ensure the survival and resilience of a planted forest, it is vital to use material with appropriate levels of genetic diversity, consistent with local or regional genetic variation.
Plan ahead: From seed collection to tree planting, develop the required infrastructure, capacity and seed supply system well in advance.
Learn by doing: Planning decisions should be made by combining both scientific and indigenous knowledge. Ideally, small-scale trials should be implemented before large-scale tree planting commences, to test the effectiveness of proposed techniques.
Make it profitable: The sustainability of tree re-planting rests on a source of income for all stakeholders, including the poorest.

 

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Is Sargassum seaweed harmful to humans?

In the centre of the North Atlantic Ocean, amidst the vast blue expanse, is a huge floating mat of brown seaweed called sargassum. These mats are quite common in the Sargasso Sea, a region around Bermuda. The region has been named after the seaweed. These floating mats of seaweed were first reported by Christopher Columbus in the 15th Century. But since 2011, the Atlantic Ocean has been witnessing massive sargassum blooms every year. It stretches nearly 9000 km from West Africa to the Gulf of Mexico. Scientists call this the Great Atlantic Sargassum Belt. The seaweed band has been getting bigger every year, posing a serious threat to marine life, coastal ecosystem and the fishing communities dependent on it.

Sargassum is a genus of large brown seaweed (a type of algae) that floats in island-like masses. The seaweed species found in the Great Atlantic Sargassum Belt include Sargassum natans and Sargassum fluitans. They have many leafy appendages, branches, and round, berry-like structures called pneumatocysts, which keep them buoyant and close to the surface. The seaweed band attracts fish, shrimp, crabs, birds, and turtles, providing essential habitats. The seaweed is in turn nourished by the excrement of these organisms. Even larger creatures find plenty to eat amid the sargassum.

While the seaweed can be a boon for marine wildlife under normal circumstances, too much of it can pose a huge problem. As sargassum decays it consumes the oxygen, creating low oxygen conditions that affect marine life. Coral reefs and seagrass ecosystems can suffer when high levels of sargassum change water chemistry and block organisms from moving freely. Thick mats can also block sunlight from reaching the ocean depths. The seaweeds often wash up ashore en masse and choke coastal ecosystems. As the seaweed rots, it releases foul-smelling hydrogen sulphide gas, causing respiratory illness in local populations. They also affect coastal tourism.

Recurrent blooms

Scientists are concerned over the recurrent blooms having become the new normal. They attribute it to various factors such as warming of the ocean due to climate change, discharge of nutrients (nitrogen and phosphorus) from agricultural run-off and wastewater originating from major river basins such as the Congo and the Amazon and the deposition of iron and nutrient-rich Saharan dust on the ocean. Scientists say that multidisciplinary research and international efforts are required to address this issue.

 

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What is NGT and what are its functions?

You must have read about NGT banning firecrackers in areas where air quality is “poor”. But do you know what NGT is and what its functions are?

NGT is the National Green Tribunal established in October 2010 under the National Green Tribunal Act 2010. A specialised judicial body, it has over the years emerged as a significant player in environmental regulation in the country, passing strict orders on issues ranging from pollution and deforestation to waste management. People can approach the tribunal against projects that affect the environment or seek compensation for damages caused due to violation of environmental laws.

Civil cases heard The NGT deals with all civil cases under the seven laws related to the environment which are the Water (Prevention and Control of Pollution) Act, 1974; the Water (Prevention and Control of Pollution) Cess Act, 1977; the Forest (Conservation) Act, 1980; the Air (Prevention and Control of Pollution) Act, 1981; the Environment (Protection) Act, 1986; the Public Liability Insurance Act, 1991; and the Biological Diversity Act, 2002. Any violation pertaining to these laws or any decision taken by the Government under these laws can be challenged before the NGT. From individuals and conservation groups to the community at large, anyone can file a case against everyone – from the State pollution control board to the Union government- at the NGT by paying a fee. The cases are to be disposed of within six months from the date of filing. The proceedings of the tribunal are conducted only in English. The NGT has as much power to grant relief as it has to impose a penalty for non-compliance of its orders

How does the NGT function?

The main bench of the NGT is in New Delhi, with regional benches in Pune, Bhopal, Kolkata and Chennai having jurisdiction over specific geographical areas.

The NGT has a chairperson, who is a retired Judge of the Supreme Court appointed by the Central Government and judicial and expert members. Besides, expert members are required to have a minimum of 15 years experience in the field of environment, forest conservation and related subjects. Though the NGT is supposed to function with a minimum of 10 members and a maximum of 20 members who will serve a five-year term, the number has been changing over the years. According to latest reports, it has only six members and a chairperson, retired justice Adarsh Kumar Goel.

Quick facts

  • Over 400 cases were heard by the NGT via video conferencing till June-end during the lockdown period.
  • The tribunal on its own passed several directives on COVID-19 waste management, as its improper handling poses a grave threat to the health of the environment and the people.
  • It also dealt with matters relating to solid waste management and rejuvenation of water bodies such as the Ganga and the Yamuna.

How climate change can impact bird life?

Migration pattern

The impact of climate change on birds’ migration patterns has been noticed in the last few decades. Scientists have documented that fewer birds show up in breeding and wintering grounds and they attribute it to the increasing temperatures changing vegetation and extreme weather conditions.

Birds synchronise their migratory movements with seasonal changes. The start of their journey and their speed must match the life cycle (before caterpillars pupate) of food sources at the stopover and destination sites. But these environmental cues go for a toss with changing climate.

Lack of food

A number of birds has adjusted breeding times to match early Spring. They arrive at the breeding site earlier than before. Meanwhile, increasing temperatures also make the vegetation bloom and insects hatch earlier at the site. But sometimes these shifts are not in line with each other. As a result, the chicks hatch way after the caterpillars are gone. And so, they starve. (On average the window of time when birds lay their eggs has gotten earlier by almost two weeks over half a century. Since many small songbirds can raise their young in roughly one month, two weeks is a big shift in their timing.)

Habitat loss

One of the major effects of climate change is the loss of habitats. While some species face shrinking ranges, others face habitat destruction. For migrating birds, flooding or desertification could spell doom. Flocks might fly thousands of kilometres only to find their destination submerged or barren. Many goose species use the Siberian tundra’s rocky bedrock to raise their offspring. But increasing temperatures make the permafrost soil to thaw and change the habitat completely, making it impossible for the geese to breed.

Sea-level rise

Sea-level rise and erosion alter coastal wetlands. Many birds, such as piping plovers, that inhabit coastal areas lay their eggs directly on the sand of the beach in a shallow depression. The erosion of beaches and storm surges can cause nests to be lost to the ocean.

Lack of sea ice

Climate change affect penguins in two ways – non-availability of food and nesting habitats. The Adelie penguins nest on land during the summer, and migrate during the winter to the edge of the sea ice, where they feed at sea. As icebergs break off in warming Antarctica, Adelie penguins are forced to take longer routes to find food in the ocean.

Antarctica’s climate is generally cold and dry but warming could cause unprecedented rain or melting of ice, creating puddles on the ground. This is bad news for penguins that lay their eggs on the ground. Their eggs cannot survive when they are lying in a pool of water.

Chinstrap penguins, which also breed in Antarctica, are affected by melting ice. Lack of sea ice affects the abundance of krill their main source of food.

Smaller body, larger wings

A study published in December 2019 found that global warming was causing birds to shrink and their wingspans to grow in size. Scientists explained that it could be more adaptation of birds as smaller birds are better at cooling off, losing body heat more quickly due to their larger surface area to volume ratios. But smaller body size means less energy available for the birds to complete long journeys. Scientists say that birds would have evolved to grow long wings to compensate for their smaller bodies as it helps them survive migration.

Will birds be able to adapt to climate change?

In the past, species and ecosystems were able to respond to global temperature shifts because average global temperatures changed slowly. Now, the change is simply too fast for many species to adapt. As we saw earlier, birds are adapting ways such as starting their migration early to match earlier Springs, but scientists are not sure if they will be able to keep up with the speed of climate change.

 

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How do floods happen?

Many floods happen when it rains very heavily and rivers overflow. They burst their banks and flood the land all around. You also get floods in stormy weather when high tides or gigantic waves sweep on to the shore.

Amazing! The Thames Barrier was finished in 1984 to stop the River Thames flooding and drowning London. Ten huge steel gates swing up to make a massive dam.

What are flash floods?

Flash floods are floods which happen very suddenly, with no warning. Sometimes there isn’t time to evacuate buildings in the flood’s path. Flash floods can happen in the desert too, during a rare downpour of rain.

Is it true? Floods can wash whole buildings away.

Yes. In 1955, a flood in the USA washed a four-storey wooden hotel clean away. Imagine how surprised the guests were when they looked out of their windows!

Are some floods useful?

Yes, they are. The River Nile in Egypt used to flood every year, leaving rich mud on the fields. The mud made the soil ideal for farmers to grow bumper crops. The Nile doesn’t flood anymore because a large dam was built to store its water.

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From Kerala to Assam, floods cause widespread damage

The one word used repeatedly to describe several natural events across the world this year has been “unprecedented”. And it is no different for rains and subsequent floods. Be it Assam and Kerala in India, neighbours China, Bangladesh and Nepal or far away Africa and the U.S., the quantum of rain dumped so far has been unheard of, resulting in floods and landslides. And it did not help that these rains have come in the midst of the pandemic, rendering a twin blow to the people. According to new reports, monsoon rains this season have affected about 10 million people in South Asia alone, and this includes 1.3 million in Assam. In September, large areas of Africa witnessed rains with intensity not recorded earlier. In mere seven hours, Senegal recorded an amount of rain that usually takes an entire rainy season from July to September! Such a crisis causes loss of not just human lives but also of wildlife. Assam’s Kaziranga National Park lost more than a 100 wild animals, including about a dozen endangered one-horned rhinoceros in the recent floods. Rains and floods also damage or change landscapes permanently, in the process shrinking or destroying wildlife habitats and causing ecological imbalance. Experts point out that extreme weather event could be a result of human-induced climate change. This change is so swift and continuous that it does not allow for nature to heal or recover, threatening to trigger irrevocable consequences for the entire planet and all of its inhabitants.

Did you know?

This July, a few residents of Assam were greeted by an unusual visitor or two – one-horned rhinoceros (occasionally with a little one in tow) escaping Pobitora Wildlife Sanctuary, about 90% of it flooded by the swelling Brahmaputra. The sanctuary has the distinction of nurturing the highest density of rhinos in the world. But it also means these pachyderms jostle for space. And floods certainly don’t help. So the fortunate and smart among the lot moved to the fingers of the sanctuary and made themselves comfortable at the houses there – rent-free! While some residents were thrilled, some weren’t. However, no instances of human-animal conflict were reported.

 

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What are the causes of melting ice in Antarctica and Arctic?

This February, Antarctica witnessed its hottest temperature on record, resulting in widespread melting of nearby glaciers. During the period, images showed drastic changes in just nine days. Then came the news that Antarctica’s colossal Thwaites Glacier is melting fast. If the glacier were to collapse, it could lead to an increase in sea levels by around 64 cm. In mere two days, the Milne ice shelf lost over 40% of its ice over in July. And then, that ice shelf – the last intact one in the Canadian Arctic – collapsed into the Arctic Ocean. The month following this, residents of Italy’s Aosta valley were told to evacuate, fearing that a huge portion of the Mont Blanc glacier could collapse. The same month also brought in the worst news so far. A study – of nearly 40 years of satellite data – published in the journal “nature Communication Earth and Environment” said that Greenland’s glaciers have passed a tipping point of sorts. It means that glaciers on the islands have shrunk so much that even if global warming were to stop today, the ice sheet would continue shrinking. The study said “the snowfall that replenishes the ice sheet each year cannot keep up with the ice that is flowing into the ocean from glaciers”. The melting of several glaciers globally has raised concerns on further sea-level increase. Throughout history, sea level have increased and decreased substantially. But the recent rise has crossed the average rate of the last few thousand years, and is increasing sharply and swiftly. If this tends to continue, it could lead to dramatic changes in coastlines the world over, caution experts.

Even as scientists and environmentalists the world over fret over melting glaciers, a new study in August appears to offer some solace. The study by Northumbria University, published in “Nature Geoscience”, revealed that the blanket of rock debris offers glaciers more protection from climate change than previously known. The expanse of rock debris on glaciers, a factor ignored in models of glacier melts and sea-level rise, could be significant, the study added.

 

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What has been the biggest bushfire in Australia?

After raging on for several months since the previous year, one of the worst Australian bushfires seasons and wildlife disasters came to an end in March 2020. The season was far worse than any prediction, and according to the BBC, “burned an area of land the size of South Korea”, killing or harming almost three billion animals. The wildfire events for the year did not end there – they have raged on in several regions of the world, destroying different kinds of ecosystems, ranging from tundra to rainforests. The Brazilian Amazon has lost large swathes of rainforests. In just the fire seven months of 2020, more than 13,000 sq.km. burned. The story is the same in the Pantanal wetland region of South America – by September, “fires had charred an estimated 24,000 square kilometers”. The tundra ecosystem of the Arctic region wasn’t spared either – in July and August, “abnormally warm temperatures spawned an intense fire season in eastern Siberia”, according to NASA. When the season waned, it had emitted 244 megatonnes of carbon dioxide. But the worst of all was yet to come – wildfires in the U.S. Even as the eastern part has been pounded by rains, the West has been battling a series of wildfires. By September, across 12 American States, as many as 100 large wildfires have burned 4.6 million acres. These include timber-dominated ecosystems. India too suffered its share of woes hen in May, forest fires in Uttarakhand left nearly 175 acres of land – part of forest ecosystems – destroyed. And today, we’re back to staring at Australia’s bushfire season. Experts say wildfires are a natural part of many ecosystems. But “the scale, intensity, speed, location, and timing of the recent infernos stand out”, perhaps warranting a closer study of global warming.

As wildfires continued to rage in Australia early this year, New South Wales (NSW) officials air-dropped more than 1,500 kg of sweet potatoes and carrots. These were for the endangered brush-tailed rock-wallabies. It is said that this was the largest such food drop ever done in NSW. The move was also important because most of the 15 species of wallabies are endangered. Sharing on social media an image of a wallaby nibbling on a carrot, an Australian minister called the marsupial “One happy customer.”

 

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Has the government diluted clearance norms for business benefits as claimed by the concerned public?

In the last few months, the new draft Environment Impact Assessment (EIA) 2020 proposed by the Centre has been drawing a lot of attention. EIA comes under the Environment (Protection) Act, 1986, and ensures projects, including industrial and infrastructural, are duly given or denied environmental clearance based on expert assessment. The first EIA norms were notified in 1994, and they were replaced with a modified version in 2006. The current government says it has redrafted this version to make the EIA “process more transparent and expedient”. However, the new draft has caused outrage among the media, activists, environmentalists and the public, and has raised the concerns of even the United Nations for various reasons. Among them are post facto clearance (projects can come up without environmental clearance); the exemption of several large industries and projects from public consultation; shortening the period of public consultation hearings; increasing validity of the clearances for mining projects and river valley projects. The draft is seen as giving more power to the government while diluting public involvement in protecting the environment. However, Prakash Javadekar, the Minister for Environment, Forest and Climate Change, has said that valid suggestions and objections raised on the draft EIA Notification 2020 will be considered on merit before finalising it. He also said “public consultations were still underway and suggestions can be sent up to 120 days from the date of publication of the draft”. He said it was wrong to assume that “ex-post facto environmental clearance will be given to the cases involving violation”. Similarly, the draft does not talk about diluting the process of public hearing, “instead it is stressing on making it more meaningful”, he said.

This May, gas leaked from a polymer plant in Vishakhapatnam, killing about a dozen people. It was discovered that the plant had been functioning for more than 20 years without clearances. The National Green Tribunal, the country’s top environmental court, has sought a high-level probe into the incident. The same month, due to lack of proper adherence to environment norms, the natural gas of an oil company in Assam had a blowout and caught fire. The oil field borders the Dibru Saikhowa National Park, putting “all life forms in the vicinity at risk”.

 

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