Emerald Green and Sapphire Blue
∼fantasy and facts∽
Dr. Satyabrata Ghosh
Ex-Associate Professor, Department of Botany
Sree Chaitanya College
West Bengal 743268 - INDIA
Hold it! Do not get your eyebrows raised. Surprised! Don’t be. No it is not a narrative about stones and gems; yet something more precious than all the gems and gold; these are priceless which no money can buy.
In the cold dark night of November 17, 1998, from the roof top I was viewing the most wonderful and spectacular celestial event of my life – the Leonid meteor shower, coming from the Tempel – Tuttle comet (the comet 55p – discovered independently by E W L Tempel on December 19, 1865 and by H P Tuttle on January 6, 1866; Kondrat'eva and Reznikov, 1985; Beech, 1998; Jenniskens, 2006; Maslov, 2007; Rendtel and Arlt, 2009). The tiny sparkling meteorites were traversing from north east to south west, illuminating the whole sky with their short-lived nanosecond sparklers, displaying the bursts of all the possible colours. All on a sudden, to my utter surprise, a few of them started turning and twisting and hovering over instead of traversing the course. It was unbelievable. Letters, words and finally the sentences were being formed by those tiny heavenly glimmers. And started vanishing as they appeared. I heard something; a strange discourse with an admonition. For reason unknown my eyelids were getting heavier and I fell asleep. Then came a heavenward thundering whisper “Leonid calling – wake up – disseminate what you have seen – save blues and greens – commit no sin”. I woke up, heavily perspiring and found nothing. The same old dark sky was twinkling with the pulsars. Sitting alone in the glooms of dewy winter night and staring at dark, my memory went blank momentarily until my paining neck and backache reminded me of the Leonid events. Laughed at myself – Have I really seen any skywriting meteors? No, I have not! It is not possible! These are all illusions coming out of stresses and strains for watching the event for so long.
Nothing happened; nothing came to my mind in these long fifteen years till the June 6th of 2013, the world environment day. In the midnight, it was drizzling outside, the thunder woke me up and with the rumbles came the same heavy whispering voice reminding me every details and asking me to tell the world about whatever I had seen on that ‘Leonid – night’-“Whoever reads the Sky-write is destined to disseminate my admonition; ignorant is the sinner of ignoring my commandments”. I could not move my limbs for long. A chill was crawling along my spine with the thought of a dire consequence. Forgive me O’ Lord! Now I have to let you all know what was written in the sky on that night, and whatever I had heard – find them in the followings, remember and disseminate or else! He knows!
The Sky-write – His Almighty the Creator, created life and all that has been destined to be eternal; the Creator painted them all with colour, every colour has been empowered to speak for itself; it has been vowed that the creations shall not be destroyed unless a sin is committed by the Created; and to give them all a chance, and to balance his creation, on a dark celestial night He created man – the sinner, and gave them intelligence – the power to view, to perceive, to realize, to understand and at the end to appreciate the language of all these colours; the sin is committed with this power only and only this power can reverse it.
And the Devine Voice – the voice came from the pulpit of heaven and said “at every point of sin committed, at every moment pain is inflicted on Mother Nature by the sinner, the Colours shall look fader and long before all the Colours fade out the sinner shall be withdrawn from the scene, forever”.
To have his mercy upon us, to save our soul, and to protect and restore the colours, we should know how all the sin has been committed and how the divine laws of Mother Nature have been transgressed against. Followings are the prelude to perceive the meaning of all these heavenly colours that have bonded all forms of inorganic and organic life together and to understand how the colours are fading away.
From distant space our planet earth looks blue that gives its characteristic name ‘the blue planet’ (Drinkwater et al, 2009). A closer look shows a seamless colour mosaic of vibrant blues with greyish white coils – our vast oceans, ice and atmosphere; and wide and dense brilliant greens and browns – the plants on our land mass – the markers of origin and evolution of our ‘cellular life’.
Surface of the planet earth is surrounded or covered by layers of various gases, called atmosphere, and these gases are retained around by the gravity of earth. The most important components of the atmospheric gases are Nitrogen/78.084%, Oxygen/20.946%, Argon/0.934%, Carbon dioxide/0.035%, and Hydrogen/0.000055% and lesser amount of no less important gases as Helium/0.000524%, Neon/0.001818%, Methane (CH4)/ 0.0001745%, Krypton/0.000114% etc. Beside this water vapour or moisture is always present @ more or less 1% v/v. The atmosphere is stratified and from topmost to the lowermost, extending from sea level to a maximum of 800 km, there are mainly five layers namely Exosphere, Thermosphere, Mesosphere, Stratosphere and Troposphere, and also with certain very important intermediate layers as ozone layer and ionosphere. The troposphere with denser gaseous molecules varies in height extending upto 9 km (at poles) to 17 km (at equator). This troposphere, together with stratosphere, holds more than 80% of the atmospheric mass and supports all sorts of autotrophic and heterotrophic modes of life. It is known that light energy of shorter wave lengths are scattered most by these gas molecules and in the denser zones of troposphere and stratosphere most of the scattering occurs by the high energy gas molecules. Therefore, as the blue light is most scattered, the sky looks blue and also this turns our large mass of oceans blue as the later reflects the sky-blue (Mitchell, 1989; Lutgens et al, 1995; Houghton et al, 2001; Wallace and Hobbs. 2006; Zahnle et al, 2010; Blasing, 2013).
The blue is losing its hue every moment by the presence ever increasing pollutants resulting from countless ways of anthropogenic activities. Our present agricultural practice, industries, urbanization, automobile emission, mining (particularly of fossil fuels, metals and calcium compounds) and electricity generation, coupled with deforestation to procure timber and to open up new agricultural and urban areas are the prime factors responsible for the accumulation of pollutants in our environment and particularly in our atmosphere. Every manufactured item we consume is adding more pollutant to the environment. The most notorious polluting agents as various oxides of carbon (CO, CO2), oxides of sulfur (SO2, SO3) and oxides of nitrogen (NO2, N2O, NO), chlorofluorocarbon (CFC), methane (CH4), formaldehyde (HCHO) etc. are collectively called Green – House – Gases (GHG) and are responsible for Global Warming and El-Niño, two most notorious phenomena of the Anthropocene age. Oxides of heavy metals, ozone (O3) and various volatile hydrocarbons (VHCs) or volatile organic compounds (VOCs) are other dangerous atmospheric pollutants coming from auto-emissions, metal industries, manufacturing and processing of paints and all sorts of industries which burn fossil fuels. Do we need all these to survive? No way. Most of them are junk. Judicious selection is the demand of the day. And the rest of the answer is ‘Go Green to save Blue’.
With the reduction of carbon and origin of carbon based organic molecules, organic life began on earth. The inherent property of organic molecules to undergo rapid change under the influence of all sorts of physical, chemical and biological factors sets the inevitable course and pace of change over time, called evolution, which led ultimately to the origin of cellular life on earth predictably about 4 billion years ago (bya or BYA). Approximately 4 – 3.5 billion years’ (byr/BYR) history of organic evolution and diversity of cellular forms had
have a number of climax points before and after all the five major ‘Mass Extinction Events’ which occurred during the Ordovician Period (Ordovician–Silurian extinction event - end Ordovician or O-S: 450–440 Ma/million years ago or mya/MYA. Two events occurred that killed off 27% of all families and 57% of all genera); Devonian Period (Late Devonian extinction: 375–360 Ma near the Devonian Carboniferous transition - a prolonged series of extinctions eliminated about 70% of all species); Permian Period (250 mya at the Permian-Triassic transition. Earth's largest extinction killed 57% of all families and 83% of all genera), Triassic Period (205-180 mya at the Triassic-Jurassic transition; about 23% of all families and 48% of all genera - 20% of marine families and 55% of marine genera went extinct –Jurassic extinction event - End Triassic)) and Cretaceous Period (65 mya Cretaceous – Paleogene extinction event - End Cretaceous, K-T extinction, or K-Pg extinction; 75% of species became extinct).
It has been estimated that each and every climax was built up with new species and only less than 1% are extant of all the species ever existed (Schopf,1983; Abramov and Stephen 2009) on earth before every ‘mass extinction event’.
Biological diversity of the Holocene Epoch is an accumulation of species evolved over 35 million years (myr/MYR) since the Eocene Epoch and long after the ‘Dinosaur Extinction Point’ in the fifth mass extinction event, during late Cretaceous Period about 65 mya (Lyons et al, 2004 a). Present biodiversity climax has been resulted from a species explosion after the end of the Ice Age about 0.01mya and may be the last climax of all, as is being feared by the scientists from every discipline of science, if the degree of devastation of ‘nature and natural resources’ by a single species, the Homo sapiens Linn. (1758) Ssp. sapiens continues to remain unchanged and unchecked.
This ‘mass extinction event’ of the Anthropocene age (Zalasiewicz et al, 2008; Revkin, 2011), is being designated by the naturalists as the ‘Sixth Mass Extinction’ or ‘Holocene Extinction’ and the sixth mass extinction exceed rates of loss in the five previous mass extinction events in the fossil record (Lyons et al, 2004 b).
All the recent data, accumulated from every possible discipline of scientific research, had been telling us every day of the last five decades that all these ‘greens and blues’ are getting fader and fader every moment with an ever increasing pace.
The origin of the green pigments, the chlorophylls, and ultimately the appearance of cellular forms enclosing these pigments, curved the atmosphere of earth in an inevitable and an irreversible way by liberating free oxygen molecule from water to the atmosphere and consequently slowly increasing the concentration of free oxygen in the atmospheric which finally became saturated and stable with oxygen at its present state (20.946% v/v or 209,460 ppmv). The obvious outcome of the availability of free atmospheric oxygen is the origin of ‘aerobic or oxygen dependent forms of cellular life’. The pattern and course of evolution of oxygen dependent multi-cellular visible forms of living objects proceeded further along the innumerable varieties of autotrophic – heterotrophic or producer – consumer cyclic relationship where conversion of inorganic molecules into organic remained always the key of all processes and factors. These evolutionary sequences synthesized a web of relationship in between autotrophs and heterotrophs where the loss of any single one shall adversely affect the sustenance of many others in a chain reaction (Olson, 2006; Buick, 2008; Javaux et al, 2010; Beraldi-Campesi, 2013).
These green pigmented cells with the cellulosic outer cover, the cell wall, are called plants. When the vast ‘Blue Ocean and the Sky’ is the maternity of cellular forms of life and the Greens, the Green living beings are the protectors of all the Blues of our mother nature.
Plants range from tiny microscopic algae to gigantic Sequoia Endl. (Sequoioideae; Cupressaceae; Pinales) and Sequoiadendron (Lindl.) J. Buchh., which can attain a height of 95m with a girth ranging from 15 – 20m (Harvey et al, 1980; Ornduff, 1994). Plants and microorganisms work in tandem to convert inorganic substances into organic compounds, together can occupy every possible niche on this planet and make every niche habitable.
Pigmentation and autotrophism form the basis of the colourful world of living beings. Life depends on this interaction between autotrophs and heterotrophs or more elaborately between green plants, microorganisms and animals.
These green plants provide us with food, fodder and pharmaceuticals, and in the way keep the planet cool by entrapping enormous amount of solar energy and CO2; liberate free oxygen into the atmosphere that we need most to breadth our life; absorb most of the pollutants to serve as the pollution sink; the network of root system hold the soil tight and prevent rivers and rivulets from being choked by runaway soil and thus prevent overflowing of running water system causing flood during monsoon times; root systems make the soil porous and prevent loss of surface water, and thereby help build up underground natural water reservoirs; green leaf surface absorbs enough solar radiation to keep the tropospheric column cool and transpiration add huge amount of moisture to atmosphere and together these phenomena help rain-cloud formation and precipitation – and the list in unending – and at the end have made the planet habitable for every creature to evolve and survive.
To keep planet habitable the earth needs plants and to survive the plants require every other prokaryotes and eukaryotes in a network called Biodiversity. To safeguard our biodiversities we need to know them well and we should find a way to assess a biodiversity qualitatively and quantitatively.
It is the degree of variation of various forms of life within a given space or in an ecosystem, in the formation of a biome, in a niche or in an entire planet. It is a manifestation of nature or health of the ecosystems (Edward O.Wilson 1988). Biodiversity is in part a function of climate. It is the only situation Mother Nature has given us for the manifestation of all the hues possible.
The term BIOLOGICAL DIVERSITY was used first by wildlife scientist and conservationist Raymond F. Dasmann in 1968. In 1980s it came into common usage in science and environmental policy. Thomas Lovejoy, in the foreword to the book - Conservation Biology, introduced the term to the scientific community. Until then the term "natural diversity" was common. In a Science Programme of The Nature Conservancy or TNC, USA – Robert E. Jenkins, its head, Lovejoy and other leading conservation scientists at the time in America advocated the use of "biological diversity". The term's contracted form Biodiversity had been coined by W.G. Rosen in 1985 while planning the 1986 National Forum on Biological Diversity organized by the National Research Council (NRC). It first appeared in a publication in 1988 when socio-biologist E. O. Wilson used it as the title of the proceedings of that forum.
Symbiotic Interaction – Survival of every species in a biodiversity depends on its interaction with other species in that particular niche. An association or a bond is formed in between microorganisms, plants and animals in a niche where all the involved components are benefitted from each other and has become indispensable for each other. This association or bondage is called Symbiosis. A variety of insects as termites, leaf-cutting ants, ambrosia beetle etc. culture fungi and form fungal garden, from which they derive essential nutrients and without which nesting or colony structure maintenance may not be possible and a particular fungal species or strain gets a vertical clonal transfer in the colonies originated from a particular colony, in a given space. However, as the genetic studies show variations in the fungal strains in different colonies, over a greater area, a polyphyletic origin and horizontal transfer is also indicated. This association includes varieties of fungal genera as Termitomyces, Leucoagaricus, Lepiota, Auricularia, Xylaria etc (Trappe, 1987; Alexopoulos, 2004). From pollination to dispersal and germination of seeds, from nitrogen fixation to providing protection to plants from pests and predators, the patterns of symbioses are unending. Each and every autotrophic and heterotrophic microscopic and macroscopic species in a biodiversity forms an integrated interactive web with each other in such a way that the loss of a single species brings a cascade effect of devastation of the whole biodiversity. Aanen et al, 2002). All the tree species and almost all the perennial herbs and shrubs in their root systems develop an inseparable and indispensable association with fungi called mycorrhiza (or actinorrhiza – when in association with Actinomycetes), where the fungal symbionts get nutrients from plants and help the plants to survive and grow precisely by protecting the roots from soil borne pathogens, by solubilizing minerals, particularly phosphates, to be absorbed by roots and by increasing the water holding capacity in the rhizosphere (
Assessment – From the preceding line it is now clear that the very survival of our own species is at stake. Somewhere, at some point, we have ignored the admonition and have started dishonoring nature’s will of our origin. Now let us be a little optimistic. May be it is not yet far too late. We have now to protect and reinstate whatever is still there; because we are the only species made to be answerable to our future. To protect, we have to know, to understand and to assess the degree of variation in a biodiversity. And at this juncture the implication of mathematics is absolutely unavoidable.
Diversity of a niche or of an ecotone is assessed and expressed in terms of an index. The most popularly used indices are Shannon’s Index and Simpson’s Index (Colinvaux, 1973; Jost, 2006; Tuomisto, 2010 a, b; Ghosh, 2012)where Species Richness (S) and Relative (Proportionate) Abundances of Individuals (Pi) are taken into account for further determination of Species Diversity. The Diversity Indices of individual ecotones can be expressed and compared in terms of Shannon’s index (Shannon H) and Simpson’s index (Simpson D, which may be expressed as reciprocal of D as 1/D or as 1-D), using the following formulae as,
Where H = Shannon diversity index, Pi = fraction of the entire population made up of species I, S = numbers of species encountered, ∑ = sum from species 1 to species S, ln is natural logarithm and D = Simpson’s diversity index (ED Simpson’s equitability or evenness). Shannon's equitability (EH) can be calculated by dividing H by Hmax (here Hmax= lnS). Equitability assumes a value between 0 and 1 with 1 being complete evenness. The species evenness or equitability can be calculated and expressed in terms of Shannon EH and can be compared with same expression of Simpson ED. It is now evident that with decrease in types (which in ecology is usually species and may even be higher taxa) in any data set the equitability or evenness index value approaches zero (0) and with single species (type) dominance the equitability value falls. However, increase in number of species (types) with frequency of individuals showing evenness the equitability index approaches one (1). Here, at this juncture, it should be mentioned that these preceding methods may not be enough and all to understand and explain true diversity of samples (types, species etc.) in a data set. It depends on the purpose, character and nature of the weighted mean of proportional abundances of types (species). While in Shannon Entropy the weighted geometric mean of proportional abundance has been considered, the other entropy (namely Herfindahl-Hirschman index or HHI – with the same result as of Simpson’s index, Gini-Simpson index – to measure the Probability of Interspecific Encounter or PIE, Gibbs-Martin index or Blau index, Berger-Parker index, Rényi entropy etc.) may have a different weighted mean of proportional abundances (as generalized mean, harmonic mean or arithmetic mean), depending on the purpose and nature of the study (microbiological, economic, demographic, sociological, psychological etc.
Human Impact – From palaeontological and palaeoanthropological evidences on biodiversity it has been revealed that since the emergence of human beings biodiversity reduction or destruction has become a regular phenomenon. Initial phase of destruction occurred at slower pace and is attributable to indiscriminate killing or hunting which in many occasion wiped out a variety of rare and endangered species and thereby reducing altogether the basic genetic diversity that we had been gifted with by nature. Loss of genetic diversity is equivalent to putting the processes of natural evolution backward. The mass killings were not always associated with hunting for food. Predatory conflicts arising from competition in the same hunting area, fear psychosis because of poor night vision coupled with death from animal attack, advantage of hunting in the open grazing land (the Neanderthals – Homo neanderthalensis, with heavily built upper part and poor legs, preferred hunting from forest fringes), onset of archaic agricultural practices and many more related factors forced modern humans to make unnecessary killings and clearing of forest areas which resulted into habitat and biodiversity destruction.
Climatological, geological, biological and sociological evidences in recent times have clearly and correctly indicated that agriculture, fossil fuel combustion for automobiles, for electricity generation and for industrial manufacturing of human consumables, frenzied urbanization and rise in poverty with explosion in human population, the products of modern civilization, are the prime factors responsible for environmental pollution, global warming and habitat destruction culminating into the holocaust of Holocene Extinction (Vitousek et al, 1997).
Measures Taken – Although a little late, and may not be adequately, number of measures have been undertaken globally and in India. The Protocols of United Nations Framework Convention on Climate Change (UNFCCC), since it was negotiated in 1992 United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro (popularly known by its title, the Earth Summit), through the resolutions of Conferences of Parties (COP), Conferences of Member Parties (CMP) and of United Nations Climate Change Conferences (UNCCC)during their summits, from time to time, have formed the basic framework for the reduction of the GHG which is responsible for climate change and global warming (Ghosh, 2012; UNFCCC web ref.). The framework, which binds signatories’ governments upon ratification, have emphasized on minimization of fossil fuel combustion and carbon foot print watch, prevention of deforestation and complete eradication of poverty.
International – United Nations Convention on Biological Diversity (UNCBD, 1992) and Cartagena Protocol on Biosafety;
Convention on International Trade in Endangered Species – in Wild Fauna and Flora (CITES);
Ramsar Convention (Wetlands);
Bonn Convention on Migratory Species;
World Heritage Convention (indirectly by protecting biodiversity habitats)
Regional Conventions such as the Apia Convention
Bilateral agreements such as the Japan-Australia Migratory Bird Agreement
Global Summit on Climate Change (Durban Summit, 2011- extending Kyoto Protocol till 2017, Kyoto 11th December, vide COP 7, 2001& Cancun Summit, COP 16, CMP 5, 2010
INDIA – India, being a non-annex member and signatory party to UNFCCC, COP & CMP, is bound to all these international protocols and frameworks.
The Environment (Protection) Act, 1986, The Forest (Conservation) Act/Rules, 1980/2003 and The Wild Life (Protection) Act, 1972 formed the basis of biodiversity and habitat conservation in India. In tandem with the Protocols of UNFCCC a number of measures have been undertaken recently by the Ministry of Environment and Forests, Government of India.
Strategies – The conservation strategy includes several measures.
1. Removal or complete eradication exotic species so that the native species can recover their niches. Simultaneous identification of suitable species for reintroduction is necessary;
2. Biodiversity Banking by placing a monetary value on the Biodiversity;
3. Rearing or Ex Situ conservation of rare and endangered species;
4. Assessment of the gene pool and Gene Banking for future conservation;
5. Reduction or, if possible complete banning, of use of pesticides, herbicides, lichenicides etc. in an exposed area;
6. Protection of wildlife and creation of wildlife corridors and inter-state treaties in between sovereign countries are of utmost necessity.
Hopes and Dreams
At this pace of environmental pollution and destruction of nature the future of planet earth are bleak. Our last resort is our hope.
There is no harm in dreaming that with all our intelligence, honesty and humane endeavor, we shall, someday, be able to restore whatever we have lost till date.
May His Almighty have mercy to give us back our Danian biodiversity, our Rupelian flora and our Tortonian fauna.
Author is thankful to all his students, friends and followers to inspire to write this article.
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