Environment

Effect of climate change 
Sushree Shailani Suman

Perishing green plants: Is global warming the cause?
Global warming is a growing concern worldwide with climate change being the most talked subject. Its effects are well known on plants and the photosynthetic process. The increased concentration of heat-trapping greenhouse gases such as carbon dioxide (CO₂) and methane (CH₄) has accelerated global warming in manifold and led to extreme events such as cyclonic storms, typhoons, drought, unseasonal rainfall, and heat waves.

How do plants deal with global warming?
The most surprising fact about CO₂ is its ability to increase the rate of photosynthesis in green plants, particularly the C3 plants. Through photosynthesis, green plants absorb CO₂ from the atmosphere and subsequently convert it into organic products (like carbohydrates, lipids, proteins, etc.) and byproducts (like oxygen). This process has been considered as a source of carbon dioxide sequestration. 

Elevated atmospheric CO₂ levels lead to temperature rise with a concomitant increase in the rate of transpiration by the green plants. However, if the plant responds by stomatal closure, the rate of transpiration may decrease. This does not allow excess CO₂ to enter the plant and results in an increased survival rate during water scarcity. The advantages are time bound. This also has several adverse effects on the photosynthetic process as absorption of less CO₂ means stunted growth. Closed stomata for a longer duration may lead to starvation in plants. Due to less partial pressure of CO₂, the stomata will be left open, resulting in rapid water loss along with CO₂ intake. Subsequently, the plants wither, wilt and die, which may have huge social implications.

The decomposition of organic matter in the soil is also stimulated by the increased CO₂ levels to be easily made available for the plants’ absorption, which in turn increases the rate of photosynthesis and carbon fixation.

Apart from the above-mentioned facts, the enhanced level of CO₂ is also marked by increased plant growth that might sound good to the farmers. Conversely, the weeds surrounding the vegetation tend to grow at a faster rate in such environmental conditions.

But such responses by the photosynthetic plants are dependent on diverse environmental factors such as availability of water, moisture content of the soil, nutrient content, atmospheric temperature, and variable CO₂ concentration, etc. Responses may be negative or positive depending on the exact nature of changes and the factors that initially limited the growth and rate of photosynthesis.

 

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Green revolution and its loopholes

Sushree Shailani Suman

Green Revolution for Mass: The advanced Mexican agricultural technology introduced by Norman Borlaug made a way out for the evolutionary technology in India, which was initiated as a trial project by Dr. M.S. Swaminathan in the northern states of India, especially Punjab and Haryana. The technology received various approbations from the scientific circles: “Green revolution describes the spectacular increase that took place during 1967–1978, and is continuing in the production of food grains in India”- was cited by J.G. Harrar.

Advancements: Green revolution proved to be a track changer in the traditional farming techniques (introduction of tractors, thrashers, harvesters; use of chemical fertilizers, pesticides, herbicides, for instant increase in the yield, etc.) as well as replacing the traditional seeds with high yielding varieties or seeds with genetic superiority.

Prolonged Loopholes: Apart from the advantages, green revolution proved to be a bane in disguise for the farmers. It has over burdened them with the increasing costs of chemical fertilizers, pesticides as well as other chemicals. The technology aimed at increasing the production of only the staple cereal crops, like rice and wheat, that too only in the north Indian states. The technology was not well implemented or did not give a proceeding result in many parts of the country.

The genetically superior seeds demanded more water, fertilizers and other accessory chemicals, for their growth and development. The overuse of these chemical ingredients has led to the detoriation and deformation in the chemistry and structure of the soil. The natural soil microbiotas are kept aloof of the soil organic carbon content, which is their nutrition source. The unavailability of the soil carbon leads to a decrease in the concentration of the beneficial soil microbiota that plays an important role in maintaining the structure of the soil. Due to this, the soil particles are left apart and they become compact and lose the water holding capacity.

The depletion in the soil organic carbon leads to the decrease in the soil’s buffering capacity that in turn affects the pH level of the soil. Lowering in the pH level affects various parameters like the unavailability of phosphorus, magnesium, calcium, which in turn affects the physiology of the plants; stunted growth of the plants, decreased root biomass and length, etc. whereas high pH level leads to a decrease in the availability of micronutrients like copper, zinc, boron, etc., which also affects the overall growth and developmental process of the plant. Decrease in the buffering capacity also leads to an increase in the thatch layer, which in turn aggravates the pathogenic population in the soil. In order to kill these pathogens, it is needed to use chemicals that, on the contrary, kill the beneficial organisms in the soil too.

Apart from these drawbacks, the technology of green revolution has neither proved to be a long-term solution, nor has it ensured food security for the rising population of our country.

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Global Cooling: Is it really happening?

Sushree Shailani Suman,

Global cooling is an undeniable phenomenon. Earth is undergoing a cooling phase since last few years that reflects an experimental fact. But we need to understand the concept of cooling on a broader context. The world has witnessed many extreme cooling conditions over a span of years such as retribution of the Arctic ice after a summer retreat, snow fall in the month of June in Johannesburg, and a sharp fall in the global average temperature. All the phenomenon mentioned above has come into existence due to the global cooling process, and the oceans play a significant role in determining the global temperature.

Two-third of the Earth’s surface is filled with water. The oceans have greater heat capacity than the atmosphere, hence, considered as a vital portion in determining the Earth’s climatic conditions. Oceans are the long-term climate regulators as this stores an enormous amount of heat, which leads to a short-term cooling phase and reduced surface temperature. Such a cooling phase has been previously experienced by the humans during the 16^th and 18^th centuries, which was known as the “ Little Ice Age”, before the man made globl warming came into the picture that reversed the cooling trend.

So the question arises that “Is ourearth getting colder?” To know the answer first we need to analyze certain important climatic changes that are going on around.

In the recent studies, researchers have found that man-made global warming has triggered a reversal in the ocean cooling. This has been empirically proven by citing the mean surface temperature of the oceans that has increased by 0.5-1°C over 200 years. The global warming has fastened the warming process of the oceans by 20 times. The earth is facing a profound energy imbalance; the ice is absorbing more and more heat causing it to melt, and the oceans are absorbing heat energy on a large scale.

To get a clear picture of the global scenario, we need to look into the data related to the total heat content of the Earth. The data reveals that global warming has continued past 1998. This year was marked by evolution of El Nino from the Pacific Ocean that led to the rise in the 

surface temperatures on a global basis. This surely paves the way toward the alarming rise in the oceanic temperature over past few years, which means the green houses gases have been rising ever since, which has already led to a radiative imbalance temperatures.

As seen in the graph below, the La Nina or the cooling phase has appeared to be prevalent in recent years .

Global surface temperature (average of the three series from NOAA, NASA and HadCRU).  Years influenced by El Niño are shown in red, La Niña influenced years in blue.  Source:  Climate Central.

This may present a picture of the gobal cooling taking place all over the Earth’s surface. But it is not the case. The amount of heat the ocean stores during the La Nina phase is released during the El Nino. So, whenever a El Nino event will arrive this will set a new record of global mean temperature. This is because not only the upper layer but also the deeper layers that gain heat energy due to the wind movements leading to loss of heat from the upper layer, which very well explains the First Law of thermodynamics.

All these events have led to a warming trend, which has doubled (0.3°C per decade) since the past few years, and the Earth is experiencing a net gain in latent heat that we can clearly see in the picture.

 

Hence, its time for the climatologists, researchers, government officials, scientists, and people dealing with protection of Earth and its resources, to dig out future prospects for dealing with the intense climatic conditions that will lesd to restoration of the damage we have made to the Earth.

(The writer is a Volunteer of PECUC &Team Leader, ECOSAVERS Youth Network, Bhubaneswar)

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GEP: Need of the hour

Sushree Shailani Suman,

 

The gross environment product (GEP) is the most recent term the country has come across. This is also known as the green gross domestic product (green GDP). Before going into the deep circles of GEP, we need to flash light on GDP to understand the main objective behind the inclusion of GEP. 

Looking at the rapidly changing skylines of the Indian cities, developing infrastructures and associated facilities, it is least remembered by us that India is still an agrarian society. The agriculture sector provides the people with their livelihoods, incomes, and security. Agriculture is considered to be the backbone of our Indian economy, yet this seems to be invisible to our national progress reports that pursue economic growth at all costs. GDP measures the economic growth of a nation that basically deals with the development in the industrial sector, and this does not reflect the rural economic and ecological status. 

The relationship between GEP and GDP is cited below:

GEP = GDP － depreciation of fixed assets － resources and environmental costs = NDP-resources and environmental costs.

Where, NDP is the net domestic product.

The natural resources such as the forest, water, soil, forest products, minerals, air, etc., have polluted or overused for the human benefits. But the data finds no place in the GDP report. Hence, a country needs to have an appropriate mechanism for the analysis and review of the natural resources to know its loss and gain for every year. GEP monitors the loss of biodiversity or natural resources, and highlights the causes of climate change. 

To know about the economic growth in true sense, we need to consider GEP alongside with GDP that will let us know about the real development in terms of economy and environment.

(The writer is a Volunteer of PECUC &Team Leader, ECOSAVERS Youth Network, Bhubaneswar)