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ISSN: 0974 - 0376
Save Nature to Survive
: Special issue, Vol. III: 09 - 14; 2013 AN INTERNATIONAL QUARTERLY JOURNAL OF ENVIRONMENTAL SCIENCES
www.theecoscan.in
IS THERE AN UPPER AND LOWER LIMIT FOR CARBON DIOXIDE IN THE ATMOSPHERE FOR BIODIVERSITY TO FUNCTION IN THE CONTEXT OF CLIMATE CHANGE? Madhab Chandra Dash
KEYWORDS CO2 Biodiversity Climate change
Prof. P. C. Mishra Felicitation Volume Paper presented in National Seminar on Ecology, Environment & Development 25 - 27 January, 2013 organised by Deptt. of Environmental Sciences, Sambalpur University, Sambalpur Guest Editors: S. K. Sahu, S. K. Pattanayak and M. R. Mahananda 9
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Save Nature to Survive
QUARTERLY
MADHAB CHANDRA DASH Former Professor of Life Sciences and Vice Chancellor, Sanibalpur University Former Chairman, Odisha Pollution Control Board, Bhubaneswar, 45, VIP Area, Ananda Villa, Flat-101, Nayapalli, Bhubaneswar - 751 015 E-mail:
[email protected]
ABSTRACT The paper describes the National and International scenario on CO2 level in air and tolerance level of CO 2 by vegetation and human beings. The situation of CO2 emission in Odisha state has been discussed as a case study.
INTRODUCTION Is industrialization the key factor for warm climate in India in general & Odisha in particular? Is it due to the loss of forest cover in many districts? Is it related to changes in the oceanic environment in Bay of Bengal, and Indian Ocean? Is it due to the increasing transport facility? Is it due to the interaction of all these factors? Is it the natural process which scientists have not been able to decipher adequately? Will scientific analysis support the notion that industrialization & increased transportation is the sole factor for climate change? Is the available GHG sink factor in the country not adequate to absorb the GHG emitted from all sources? This paper makes an analysis with regard to the limits of carbon dioxide (green house gas) in the atmosphere for the biodiversity and human beings for a comfortable living and its relation to global warming. Green House Gases (GHG) Carbon dioxide is a colourless, odourless, nontoxic gas and essential for green plants for photosynthesis and along with water vapour and clouds, this gas keeps the atmosphere warm by absorbing radiation making living processes comfortable for most of the organisms. However, it is a green house gas and in recent times has drawn huge attention. I am a strong supporter of nature conservation and to live in unpolluted clean environment. The traffic situation, especially road conditions, infrastructure available in road crossings, discipline on the road, civic sense of people, etc is very poor in India and Odisha in particular, even at Bhubaneswar- the capital city of Odisha. There is no foot path, road crossing zones and markings, cycling paths etc in Bhubaneswar and other urban centres of India. Traffic congestion is heavy. Implementation of rules and laws etc is inadequate. Pollution level due to suspended particles, respiratory particles, carbon monoxide level in the road crossings, pathogens in the ambient air must be in the alarming state. These aspects appear to be equally important with green house gas level in the atmosphere in the country. The living body is made up of carbon and it is the living stuff in all organisms. Daily, a human being exhales on the average around 1 kg of carbon dioxide and thus in our state, we exhale on the average not less than 41,000tons of carbon dioxide per day (~15 million tons of CO2 per year)taking 41 million people live in Odisha (as per the 2011 census). Considering the Indian population of ~ 1210 million as per 2011 census, 1210 million kg (1.21 million tons per day, ~ 442 million tons per year) of CO2 goes to the atmosphere daily by human exhalation. Human tolerance to CO2 level Human beings and most of the animals will survive and will perform their functions without having much CO2 in the air but with higher concentration of CO2 in the atmosphere, physiological functioning, especially respiratory gas exchange would be very difficult (Happer, 2011). In otherwards, there may not be a lower limit but there is an upper limit that man and most of the vertebrate animals can tolerate. 10
LIMITS CARBON DIOXIDE FOR BIODIVERSITY FUNCTION UNDER CLIMATE CHANGE
NASA,USA has conducted extensive studies on human tolerance for CO2 for astronauts and NASA recommend an upper limit of 5000 ppm of CO2 for space missions for one thousand days, assuming total pressure of one atmosphere. USA Navy recommends an upper limit of 8000 ppm for cruises of ninety days in the submarines (Happer, 2011).
under increased CO2 concentrations. As it appears higher the concentration of CO2 up to certain level will increase the productivity if the temperature regime, availability of nutrients and water do not create stress. But increasing CO2 level in the atmosphere will increase the level of atmospheric temperature. Figure1 shows a generalized graph showing the relationship of the intensity of sunlight, air temperature and rate of photosynthesis in C3 and C4 plants (Dash and Dash, 2009).In high air temperature, the rate of photosynthesis goes down, especially in C3 plants (most of the plants and crops).
C4 plant
Rate of photosynthesis per unit leaf area
Photosynthesis and CO2 level Scientific studies show that the level of CO2 in the atmosphere should not be less than 150ppm for plants to continue the process of photosynthesis. However, plants usually grow better and produce better flowers and fruits at higher level of CO2 (Happer, 2011). The present level of CO2 in the atmosphere is conducive for good photosynthetic activity. Evolutionary history says that most of the green plants evolved at CO2 levels of several thousand ppms, not less than 10 times higher than the current level in the atmosphere. About 57 million years before in the Eocene period of Cenozoic era, the volcanic activity generated huge amount of oxides of carbon and other gases as the geologists and evolutionary biologists tell us (Kump, 2011). All forms of animals and many flowering plants and ancestors of modern man had already evolved in the planet by that time as scientists tell us (Table 1). Was the high concentration of CO2 detrimental to living organisms at that time? It may be that the organisms were adapted to high temperature and the biodiversity was not as rich as it is now. But the fact remains that the adaptive potential of biodiversity, especially human beings is phenomenal.
C3 plant
1%
Green plants are, however will do their functions more efficiently in increasing CO2 level in the air up to a very high concentration with other environmental conditions remaining as it is at present. For us, the important issue is the productivity of crops and productivity of other plants providing food to us
50% Full sunlight 0ºC
20ºC Temperature
100% 40ºC
Figure 1: Relationship between intensity of sunlight, temperature and rate of photsynthesis in C3 and C4 plants. Rate of photosynthesis for unit leaf area is significantly higher in C4 plants in differents sunlight and temperature conditions
Table 1: The ages of life on earth (based on Reader’s Digest Publications) Age
Events
Precambrian 4.6 billion years ago The Earth is formed 4.5 billion years ago The Moon is formed 3.8 billion years ago 3.3 billion years ago 2.1 billion years ago 720 million years ago Paleozoic Cambrian - 550 - 505 million years ago. Ordovioian - 505 - 438 million years ago Silurian - 438 - 408 million years ago Devonian - 408 - 360 million years ago Carboniferous - 360 - 286 million years ago Permian - 286 - 245 million years ago Mesozoic Traissic (245-208 million) - Juraseric (208-144 million)Cretaceous (144-65 million) Cenozoic Tertiary period (65 - 1.8 million years ago) Paleooene ( 65 -57 million years ago) Eocene (57 - 34 million years ago) Oligocene (34 - 23 million years ago) Mocene (25-5 million years ago) Pliocene (5 - 1.8 million years ago) Pleistocene (1.8 million years ago) to 50000 yrs, Holocene Quaternary Period (15,000 years ago to present)
Life No Life No Life Single celled organism Cyano bacteria or Blue Green Agae Single celled organism with a Nucleus. Murti cellular Aiimals. Trilobites & other Uterine animals with hard cell. Fishes without jaws fi corals. Land plants & Jawed fishes. Land Aiimals, Insects & Amphibians. Reptiles. Reptiles diversify. Reptiles Evol. Peak. Evolution of Birds and Ivtammals.
Birds diversify. Flowering plants, Ivtammals & Primates appear Aicestor of Modem man. Other Mammals. Homo erectus Human evolution, Homo species spread Homoneanderthalensis, H. cromagnon, H. sapiens Modern man. (H. sapiens sapiens)
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periods during the last million years or so. The planet’s climate is always changing and there may be many reasons as discussed above. About twelve thousand years before there was warming of the planet called medieval warming followed by the “little ice age” which brought famine as the crops were destroyed due to severe cold (Kump, 2011). Since the little ice age, the planet is warming up slowly and steadily. But during the last 200 years, the level of green house gases, particularly CO2 level has increased and increasing due to human activities. Therefore every nation is willing to adopt ‘green technologies’ in spite of the fact the technologies are available in few countries. In view of this green technology development and transfer is now considered as thrust areas of research and climate change activity.
IPCC shows serious concern for rise of temperature in the atmosphere and in the ocean. Besides the rise of temperature is thought to be the cause of glacier melting, loss and migration of biodiversity northward, loss of productivity, flooding of coastal ecosystems and human settlements. Increasing CO2 level in the Air Before the industrialization in Europe, the average CO 2 concentration in the atmosphere was around 280ppm and during the last 200 years, the concentration has increased to about 395ppm (115ppm increase). The current rate of burning of fossil fuels, the rate of increase in CO2 concentration has been estimated to about 2ppm per year. At this rate of increase, it would take 300 years for CO2 to reach a concentration of ~1000ppm in the atmosphere. The IPCC report (2007) shows that during this 150-200 years post industrial period, the average temperature of the atmosphere has increased to about 0.8 degree Celsius. They also predict that with the current rate of increase in CO2 and other green house gas emissions in the atmosphere, the temperature will increase by 2-4 degree Celsius, or more, which will be detrimental to many aspects of our crop productivity, prevalence of disease, housing, displacement of people from coastal areas, security, etc especially in tropical countries. Air temperature rise may enhance crop productivity in temperate climate but glacier melting and appearance of vector borne disease will increase.In view of this they advocate to change to alternate energy sources urgently so that CO2 and other green house gas emissions is reduced and impact would be moderated.
International scenario Many private enterprises, especially in industrially developed countries have invested heavily on green technologies and their role in promoting climate change programmes can not be ruled out. However most of the countries, particularly the developing countries such as India, China, Brazil, Mexico. South Africa, Argentina etc depend upon coal for their energy. The leaders of green technologies are the industrialized western countries, (west European countries, USA, Canada) Australia and Japan and hence the world environmental politics involving development and transfer of green technologies depend upon development of acceptable international protocols. Considering the scientific facts as discussed above, it can safely be concluded that CO2 level in the atmosphere is one of the factors of global warming and not the sole factor. The serious environmental issues are the habitat loss and damage to regional/local landscapes, increasing pollution load, particularly hazardous chemicals and wastes, mining activities and unplanned industrialization and massive transport system. Although carbon dioxide level of 395ppm or higher level does not create hindrance in the functioning of the living world, but it absorbs and retains heat and increase the temperature of the atmosphere. The temperature rise creates problem for the living and nonliving world and biological and physical processes.
Many scientists are of the opinion that since the Paleozoic era (~ 550 million years before), it is assumed that the ocean currents involving the fluid flow pattern and salt belt, the continental drift, massive volcanic eruptions in initial periods, the planet’s orbital parameters (Milanokovitch cycles), variations in sun’s output of all types of radiations, and some other causes were the reasons for temperature increase making the planet conducive for life. Besides the atmospheric gases played important role in the heat balance of the planet. In recent times scientists have found a strong correlation between CO2 concentrations and planet’s temperature by studying ice-core records of the cycles of glacial and interglacial
Table 2: The basis of estimations of GHG emissions from energy sector and important industrial sectors in the country with the capacity of production Energy sector: Thermal power
Industrial process sector Iron and steel production:
Ferro-chrome
Alumina and aluminum
Cement
1MWH generation requires about 17 tons of Indian Coal, which contains 32% C. 1MWH power generates about 0.79t CO2 .Hence 1000 MW, generates about 7 million tons CO2 per year. India generates ~ 119,000 MW thermal powers annually and emits about 825 million tonnes of carbon dioxide. 1 ton production of steel generates about 2.6-3.5 tons of CO2 (for sponge iron- about 2.6 ton CO2) from coal and coke. India produced ~ 44 million tonnes of iron and steel in 2006 with about 10% annual growth. The estimate of current production is about 65-70 million tonnes of iron and steel per year (CO2 generation is ~210 million tonnes at present). Future projection is > 100 million tonnes of iron and steel by 2020. 1 ton production generates about 2.1 tonne of CO2. The current Ferro- Chrome demand is estimated as 8 million tonnes (8 x 2.1 = 16.8 million tonnes of CO2 generation). (Taking the values of 84%C and 50% C in metallurgical useable grade coke and coal respectively). 1 ton alumina production using about 4 tonns bauxite ore and 1 tonne aluminum production using about 2 tons of alumina generate about 22 ton CO2. India has the capacity of ~ 4 million tonne aluminum production per year. (CO2 emission amounts to 88 million tonnes) 1 ton production generates about 0.9 ton CO2. In 2003, India produced about 117 million tonnes of cement. At present, India has ~ 200 million tonne annual production capacity. (180 million tonnes of CO2 emission)
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LIMITS CARBON DIOXIDE FOR BIODIVERSITY FUNCTION UNDER CLIMATE CHANGE
Energy scenario
The GHG sink potential Forest and tree cover of the country was 78.37 million ha in 2007(FSI, 2009), which was 23.84% of the geographical area and this includes 2.82% tree cover. Table 3 a and b gives the forest and tree cover in the country in 2007(FSI, 2009). The National goal is to achieve 33% of forest cover in India. The situation in different regions is not very encouraging. The forest cover is to be increased and special efforts are to be made. Awareness should be created in a massive manner to reduce the carbon foot print of individuals, and industries. We have to give importance on priority basis to renewable sources so that the pollution load and green house gas load to our atmosphere is lessened.
India’s energy source About 70% of our energy source (1, 70,000 MW) is fossil fuels and ~50% is coal based. Coal based thermal power plants are not environment friendly as these plants generate huge amount of GHG and pollutants such as SO2, NOx, Cox, SPM, Fly and bottom ash, metallic dust, etc. About 120-150 million tons of fly ash is generated annually in India (Jain, 2010). The utilization is only 25%-30% in brick making, road construction, forest soil fertilization, and in agriculture etc (Jain, 2010). Hence it is a huge problem. Industrial GHG Emissions Industrialization has grown manifold in India after 1947. An estimate of GHG emissions and the basis of estimations are given in Table 2.
Situation in Odisha- A case study Considering the abundant mineral deposits and water availability, and increasing transport facility, it is natural that many industrial houses are interested to invest in Odisha. Coal is our main energy source. It is abundantly available in Odisha and therefore we will depend upon coal for many decades. Coal in Odisha on the average contains 32% carbon and 40-45% ash. For thermal power generation, about 17 tons of coal is required per day for production of 1 MW. The pollution load from Odisha- coal based thermal power generation amounts to (Paribesh Samachar, 2010)
India annually burns > 300 million tonnes (Odisha > 30 million tons) of coal in power plants and generates equal amounts of CO2 from this source. There is increased need of energy in the farm, industrial and service sectors as the population continues to grow and to meet the developmental needs. Modern way and standard of living demand huge energy from unsustainable consumerism, transport facilities and increased construction work and other aspects of human use.
~19 tons of CO2 per day .MW; >136 kg of SO2 per day.MW; >7 tons of fly ash per day.MW.
Energy is the key for survival, continuance and for sustainable development. It has been estimated that by 2020, the energy production capacity of the country may reach 220,000MW, although per capita energy consumption in India is <500 units per year compared to about 2600 units at international level in industrially developed countries.
Currently > 7600 MW of thermal power is generated from different sources in Odisha (Dash, 2010 a,b). In view of this the pollution load is heavy amounting to 363861 tons of SO2 emissions per year, ~19 million tons of fly ash per year, and
Table 3a: Forest & Tree cover in India (2007) Class Forest Cover VDF (very dense) MDF (medium dense) OF (open) Total Forest Cover Tree Cover (Tree patches<1ha with canopy density> 10%) Total Forest and Tree Cover Non-forest: Scrub Non-forest Total G. A.
Area (million ha)
% of Geographical Area (G. A.)
8.35 31.9 28.84 69.09 9.28
2.54 9.71 8.77 21.02 2.82
78.37 4.15 255.49 328.73
23.84 1.26 77.72 100
Note 55.51 million ha lies <1000m, 11.67 m ha. >1000 to 3000m and 1.91m ha>3000m altitude
Forest and tree cover of the country was 78.37 million ha in 2007(FSI, 2009), which was 23.84% of the geographical area and this includes 2.82% tree cover.
53 million tons of CO2 per year. Besides, huge quantity of NOx gases, aerosols etc are pumped to the atmosphere in Odisha. Out of 30 districts, in the state, only 12 districts have forests cover exceeding the National target of 33% forest cover for each district. Another 4 districts have forest cover exceeding 23% and less than 33% and 13 districts have forest cover less than 20%.
Table 3b: Forest and Tree cover (km2) region-wise in India based on FSI, 2009) Region
Geog. area
Total forest cover % of GA Scrub
(No. of States/UT) South (5) North (9) West (4) N-East (8) South East (3) Central (2) Islands (4) Total
636,263 772,644 849,676 262,179 324,153 443,436 8,884 3,287,263
118,284 83,126 80,205 173,182 82,060 131,878 6,883 677,033
19 11 9 66 25 30 77 21
14,891 4,561 10,272 919 5,544 2,263 3 38,475
Some districts such as Bhadrak, Jagatsinghpur, and Puri have forest cover of less than 5% and districts such as Baleswar, Kendrapara and Jajpur have forest cover less than 10% of the geographical area of the district Angul and Denkanal districts and many are in the pipeline. These are important districts 13
MADHAB CHANDRA DASH
from population density and industrial development point of view. The districts of Angul, Denkanal, Jharsuguda, Sundergarh and Sambalpur are under severe stress from industrial emissions. More than 61% of thermal power of the state is generated by industries located in of industries and expansion and conservation of forest cover should get top priority in the state government development policy and should be reviewed periodically. It is right time to debate whether all green house gases should be declared as pollutant or should be included in the generic structure of Environmental Assessment document (EIA) in India? The carbon foot print of new industries keeping international and national standards in view may form part of the EIA document.
REFERENCES
Societal goal for energy consumption should change from high carbon systems to low carbon systems. Observation of environmental discipline at individual, family, societal and national level is the call of the time. In view of this good governance, judicious implementation of environmental laws, and implementation of massive awareness programmes are required.
IPCC, 2007. A Report of the Intergovernmental Panel of Climate Change, 2007. UNEP, Switzerland. 4:
Dash, M.C. 2010a. Environment, Energy & Development from Stockholm to Copenhagen and beyond the Celebrations. The BioScan, Special issue. 1:1-11. Dash, M. C. 2010b. Carbon Sink Potential of Forests and Industrial Green House Gas Emissions. Society of Geoscientists and Allied Technologist’s Bulletin. 11(2): 1-13. Dash, M. C. and Dash, S. P. 2009. Fundamentals of Ecology, TataMcGraw-Hill Publications, New Delhi. p. 562. FSI Report, 2009. Government of India, New Delhi Happer, William. 2011. The Truth about Green House Gases, First Things, (USA). pp. 33-38.
Jain, N. K. 2010. Suitability of flyash as a mine void hill meterial-a critical review. Minenvis. 64: 1-6. Kump, R. Lee. 2011. The last great global warming. www.scientifc american.com. pp. 57-61. Paribesh Samachar, 2010. SPCB, Odisha Publications, Bhubaneswar
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