16. Discussions on the Environmental Hazards Unit One

This begins a series of discussions on Environmental hazards. This is a very important area. In fact a large number of questions were asked in the Prelims of 2011. Please go through what I have written, what others have blogged and add your comments. Remember that spending an hour a day on the blogs, each one of hem and going through all blogs is a very useful way to prepare for the exams.

Only students of our Institute can participate in this activity. Those who wish to participate must first enrol themselves as students,

Karachi was flooded in 2007 resulting in thousands of deaths. There was the inundation of numerous salt mines in India in 1998. Why did these occur? Should they be dismissed as natural disasters? Recent scientific studies show that it was man’s unbridled tampering with nature that caused the havoc. According to scientists, a thickening layer of pollution over the Indian Ocean is creating atmospheric conditions that promote fierce cyclones. As a result, powerful tropical cyclones that cause large numbers of deaths and massive property damage around the Arabian Sea are becoming increasingly common.

There has been a six-fold increase in fine aerosol emissions locally since the 1930s from forest fires, domestic heating and diesel use, creating a layer of pollution 3 km thick over the Indian Ocean. This layer of haze is creating conditions that intensify cyclones and increase the chances they will reach land. The haze, known as the Asian Brown Cloud, comprises soot and sulphates spewed by factories, diesel exhaust and poorly-burnt biomass. Previous research has implicated it in disrupting monsoon patterns and in glacier loss in the Himalayas.

A research paper published in Nature by a team of scientists led by Amato Evan of the University of Virginia holds this haze, which hangs over parts of the Northern Indian Ocean, India and Pakistan, responsible for the increasing devastation in the region. “We have found a clear connection between human activity and changes in atmospheric conditions that create favourable conditions for the formation of large tropical cyclones,” said Evan. We are responsible for this and must do something to rectify the situation, instead of blaming the gods.

72 thoughts on “16. Discussions on the Environmental Hazards Unit One

  1. Since the beginning of the industrial revolution man has pumped pollutants onto the whole of the earth. It must be noted that the continuous drubbing of pollutants into earth’s weather system is without significant understanding of how the weather system on earth operates and its behavior with pollutants. Since there is large gap in knowledge in understanding of weather as a phenomenon other than descriptional knowledge and hints. Man still toys with something he does not understand fully.

    India is a monsoon dependent country and such modification of its weather patterns can affect her population by the millions. Few examples to take not off. recently in an article in ‘THE HINDU’ on the front page they spoke about how Bangalore is shifting to wetter climate and why it has resulted in a dip in the rainfall in Karnataka’s Malnad region. the pollutants over Bangalore is making the precipitation of clouds faster and also aiding in faster condensation. Thus the unusual rains in November over the city. In Idduki of Kerala ..the mist formations that aided in the growth of cash crops has disappeared and the climate around the hills is much warmer and not conducive to cash crops anymore. The end result, farmer suicides.The floods in north Karnataka two years ago is also an example of such changes. While north Karnataka was ravaged by floods coastal and Rayalaseema and Andhra went dry.

    The brown cloud will be responsible for new set of refugees in India…environment refugees.

  2. Morethan 10,000 years ago, ancient humans started living in groups. There wasn’t any apparent ownership observed over properties. Instead, every available natural resource was shared among every body. Natural resources were utilised just to satisfy everyone’s need and Mother Nature was given enough time to rejuvenate her resources. Later, in the name of civilization, man got the desire to acquire property and started commercialising the natural resources. This desire later took a swift-turn as a greed after Industrial revolution, heavily affecting the harmony between humans and the nature. Obviously a question arises at this point. Who is better civilized? Indigenous tribals who live a harmonus life with nature or the so-called modern man who eats up the natural resources rapidly everyday?

    The man-made natural hazards are attributed to the following factors.
    i)Depletion of natural resources due to
    1) deforestation
    resulting in land slides, loss of rainfall, climatic pattern changes, flooding, drought extinction of animals and more importantly stress on fresh oxygen.
    ii)Increasing pollution caused by
    1)industrial effluents
    2)automobile emissions.
    3)Burning of coal,etc
    leading to acid rain, global warming and ozone layer depletion which inturn results in climatic pattern changes and ecosystem alteration.

    How to avoid man-made hazards:
    1)By using clean energies such as Solar and Nuclear energy there by reducing the sources of pollution.
    2)Though Kyoto and Montreal protocols are adapted to restrict the emissions of green house gases and ozone-depleting substances respectively, it is pressed heavily on only developing nations with developed nations being reluctant to adopt it. Since developed nations hold more share in the emission of these gases, developing nations should persuade them to adopt the protocols strictly.
    3)Movements similar to “chipko” movement, involving general pubilc, against the indiscriminate clearing for forests and other natural resources.
    4) NGOs should play a prominent role in spreading the awareness. If the goal is not acheived in a moderate way, there is nothing wrong in graphically visualising the aftermaths and persuade people out of fear towards conservation.

    Our ancestors, through a sensible relation with nature, bequeathed us abundant resources to serve our NEED. Its our turn to be sensible and pass on the same to future generations.

    1. Eco-system is the biological environment consisting of all the organisms living in a particular area, as well as the physical and non-living components of environment the organisms interact with.
      All the components of an eco-system regulate the environmental activities like regulation of climatic processes, breakdown of wastes and recycling nutrients, filtering and purifying water, buffering against floods, maintaining soil fertility, purifying air, and provide natural resources such as wood, textiles, and of course food. All agriculture, marine and freshwater food resources depend fundamentally on Biodiversity. So, biodiversity forms the basis for human existence.

    2. The monsoon and the Western Disturbances are the two main factors which alter the weather over Karachi; otherwise, Continental air prevails for rest of the year.

      Following are the main factors that alter the weather over Karachi city.

      1. Western Disturbances mostly occur during the winter months and cause drizzle to light showers, temperature also decreases due to it.
      2. Tropical Storms usually form during the summer months from late April till June and then from late September till November.
      3. Southwest Monsoon occurs in summer from the month of July till September. Monsoon rains bring much awaited relief from the scorching summer heat. These monsoon rains are quite heavy by nature and can cause significant flooding.
      Continental air prevails during the period when there is no precipitation in the metropolis.

      With regards to the change of climatic conditions in bangalore this is got to with the rise of the population in the recent 5 years. More so it must be rembered that the climatic shift has got to do with the increase in the let out of emmisions especially the harmful pollutants such carbon monoxide, carbon dioxide levels. Despite constant awareness of the reduction levels to be maintained, the impact of warming in the mindset of people still takes a time.

      To conclude with, we must understand that ” a perfect balance” is yet and to my understanding its a distant dream to achieve it. Definitely the interaction of human behaviour has altered the activity so much that the natural climatic realm is taking a toll.

    3. Everything in the natural world is connected. An ecosystem is a community of living and non-living things that work together. Ecosystems have no particular size. An ecosystem can be as large as a desert or a lake or as small as a tree or a puddle.Ecosystems are dynamic interactions between plants, animals, and microorganisms and their environment working together as a functional unit. Ecosystems will fail if they do not remain in balance. No community can carry more organisms than its food, water, and shelter can accomodate. Food and territory are often balanced by natural phenomena such as fire, disease, and the number of predators. Each organism has its own niche, or role, to play.

      An ecosystem includes soil, atmosphere, heat and light from the sun, water and living organisms. Soil is a critical part of an ecosystem. It provides important nutrients for the plants in an ecosystem. It helps anchor the plants to keep them in place. Soil absorbs and holds water for plants and animals to use and provides a home for lots of living organisms.

      “Biodiversity forms the basis for human existence can be explained as follows:
      1. Formation of soil.
      2. Prevention of soil erosion.
      3. Recycling of waste.
      4. Pollination of crops.

      Since the beginning of the
      1990s the conservation of biodiversity had also become one of the central goals of
      international conservation organizations such as the World Wide Fund For Nature (WWF),
      the World Conservation Union (IUCN) and the United Nations Environment Programme
      (UNEP) (WWF, 1993a).

      The term biodiversity involves a complexity of meanings and levels. As used in the
      Convention, the term has the following definition (IUCN, 1994):
      • “Biological diversity” means the variability among living organisms from all sources
      including, inter alia, terrestrial, marine and other aquatic ecosystems and the
      ecological complexes of which they are part; this includes diversity within species,
      between species and of ecosystems.

      Thus biodiversity is the variability of life in all forms levels, and combinations. It is not the
      sum of ecosystems, species and genetic material, but rather represents the variability within
      and among them (IUCN, 1994). Biologists usually consider it from three different
      • “Genetic diversity” refers to the frequency and diversity of different genes and/or
      genomes. It includes variation both within a population and between populations.
      • “Species diversity” refers to the frequency and diversity of different species
      • “Ecosystem diversity” refers to the variety and frequency of different ecosystems

      It can be seen that these three perspectives form a hierarchy and are basically different
      ways at looking at the same thing (IUCN, 1990). All biodiversity is the result of natural
      selection working on the consequences of genetic variation (Lee, 1993).

    1. Causes of Soil Erosion

      Land use: Humans play a major role in soil erosion through their use and abuse of natural resources, for example deforestation, grazing, arable land use, faulty farming systems, high crop intensity, housing construction, mining etc.

      Climate: The two most important climatic factors having a direct effect on erosion are precipitation and wind velocity. Other climatic factors have an indirect effect on soil erosion, such as water balance, evapotranspiration, temperature and relative humidity. Indirect factors affect the erosivity of rainfall by altering the soil moisture regime and the proportion of rainfall that may become surface runoff. For erosion control it is necessary to investigate physical characteristics of rainfall, including the amount, distribution, intensity, energy load, seasonality and variability of rainfall and the formation and course of surface runoff.

      Soil: The susceptibility of a soil to erosion is influenced by its physical, hydrological, chemical and mineralogical properties as well as its soil profile characteristics. Important soil physical and hydrological properties that affect the resistance of a soil to erosion include texture, structure, water retention and transmission properties.

      Hydrology: Infiltration, surface detention, overland flow velocity, and subsurface water flow are important soil erosion components of the hydrological cycle. The different types of flow and their velocities may be turbulent or laminar, steady or unsteady, uniform or non-uniform and influence the extent of erosion

      Landforms: Slope gradient, slope length and shape of slope are the important variables of landform that affect erosion processes for all types of soil erosion, e.g., splash, sheet, rill, and gully erosion.

      Methods of preventing soil erosion:

      i) Soil erosion is the removal of soil from its surface by wind, water, and deforestation etc.
      Strong winds carry soil particles from one place to another to cause soil erosion.
      Fast running water creates depressions in the soil to cause soil erosion.
      Deforestation (cutting of trees) and overgrazing also lead to soil erosion.

      ii) Soil erosion can be controlled by the following ways:
      a) By planting more trees (forestation).
      b) By growing grasslands.
      c) By providing proper drainage system in the fields.Grassed waterways are depressions or channels constructed to serve as drainage ways. These waterways are stabilized by planting close growing crops such as crops and legumes
      d) By terrace cultivation on sloping fields..
      e) By control of grazing
      f)Crop rotation is the systematic planting of different crops in succession. Grain crops are usually rotated with legumes. This practice improves the soil structure and promotes rapid infiltration of water and reducing erosion.
      g) Bench terraces is an engineering approach to control erosion
      h) Other engineering approach in preventing soil erosion is by constructing a riprap wall where stones or boulders are piled up along the contour of the land in order to provide an effective barrier against the downward movement of soil and runoff water.

    2. The removal of the top layer of the soil by natural action of wind and water is called Soil Erosion. Most commonly by wind, the lighter sand or fertile soil particles get carried away by the wind to a distant place. And by water, it can be either by raindrop splash as well as by the run-off water. It is most common in:
      – regions where land is either do not have or have very sparse vegetative or residue cover,
      – in the hilly regions – longer and steeper the slope, greater is the erosion,
      – in springs when soil is most saturated

      Various preventing measures can be taken to prevent soil erosion like soil surface covering, terrace farming, contour plowing, strip cropping, crop rotation etc.

    3. soil erosion is an term for the detachment and removal of soil and rock by the action of running water, wind, waves, flowing ice, and mass movement. on hillslopes in most parts of the world the dominant processes are action by raindrops, running water, subsurface water, and mass wasting. The activity of waves, ice, or wind may be regarded as special cases restricted to particular environment.
      it is mainly caused due to following factors

      Climate factor

      The major climatic factors which influence runoff and erosion are precipitation, temperature, and wind. Precipitation is by far the most important. Temperature affects runoff by contributing to changes in soil moisture between tains, it determines whether the precipitation will be in the form of rain or snow, and it changes the absorptive properties of the soil for sater by causing the soil to freeze. Ice in the soil, particularly needle ice, can be very effective in raising part of the surface of bare soil and thus making it more asily removed by rnuoff or wind. The wind effect includes the power to pick up and carry fine soil particles, the influence it exerts on the angle and impact of raindrops and, more rarely, its effect on vegetation, especially by wind-throw of trees

      Soil feature factor

      The soil factor is expressed in the erodibility of the soil. Erodibility, unlike the determination of erosivity of rainfall, is difficult to measure and no universal method of measurement has been developed. The main reason for this deficiency is that into two groups: those which are the actual physical features of the soil; and those which are the result of human use of the soil.

      Geological factor

      where E is the erosion, S the slope in per cent, and a is an exponent. Values of a derived experimental range from 1.35 to 2.

      The lengh of slope has a similar effect upon soil loss, because on a long slope there can be a greater depth and velocity of overland flow, and rills can develop more readily than on short slopes. Because there is a greater area of land on long than on short slope facets of the same width, it is necessary to distinguish between total soil loss and soil loss per unit area.

      Biological factor

      Vegetation offsets the effects on erosion of the other factors-clmate, topography, and soil characteristics. The major effects of vegetation fall into at least seven main categories:

      (1) the interception of rainfall by the vegetation canopy;

      (2) the decreasing of velocity of runoff, and hence the cutting action of water and its capacity to entrain sediment;

      (3) root effects in increasing soil strength, granulation, and porosity;

      (4) biological activityies associated with vegetative growth and their influence on soil porosity;

      (5) the transpiration of water, leading to the subsequent drying out of the soil;

      (6) insulation of the soil against high and low temperatures which cause cracking or frost heaving and needle ice formation;

      (7) compaction of underlying soil.

      1. prevention for the soil erosin.

        •Gardening: . The grass and trees you plant or even the fences you put up will prevent heavy rain from beating down on your land and keep the top soil in place. It will also prevent the soil from drying up and getting blown or washed away.

        •Conservation tillage: Often used by farmers but can be adapted by gardeners as well, it is simply leaving some vegetation on the ground instead of stripping the entire area bare.

        •Keep Soil Healthy: This is an important step to prevent soil erosion. Use fertilizers, manure or compost regularly, soil thus treated becomes rich in organic matter, binds together and is less prone to being washed or blow away.

        •Plant Wind Breakers: In areas prone to gusty winds, plant wind breakers in the form of trees, hedges and bushes or even put up a wooden/plastic fence.

        •Contour Farming: If you happen to be living in the hills, this method is very useful in preventing soil erosion by slowing down the flow of water down the slopes. It is done by following the natural contours of the land while planting.

        •Avoid Leaving Land Barren: On land that is not in use one should plant a ‘cover crop’. This helps your land in two ways; to begin with it prevents soil erosion and also provides nutrients for the land in the form of nitrogen fixers if certain cover crops are used.

        •Matting: One of the commonly used products in soil conservation is ‘matting’. Readymade matting made of wood fiber is commonly used in household vegetable gardens and vacant plots. The matting which is placed on top of the soil prevents soil erosion while at the same time it allows plants and trees to grow through it.

        •Use of Retaining Walls: Very useful in areas where rains is heavy and water erosion affects the soil, one can prevent it by constructing small retaining walls around your vegetable plots. You can use bricks and mortar or even pack in heaped soil in rows.

        •Use of Mulch/Fertilizer: Another useful method is applying a layer of mulch and fertilizer over the soil. This prevents the rain from beating down hard directly on the soil at the same time water slowly soaks through the soil and enriches it. The mulch and fertilizer layer helps the soil to regain its PH levels.

        •Avoid Excess Watering: While it is important to keep the soil moist which at times may be difficult, like in summers, avoid over-watering as this washes away the top soil and degrades the land.

    1. According to the EPA recycling is “the separation and collection of materials that otherwise would be considered waste, the processing and remanufacturing of these items into new products, and the use of the recycled products to complete the cycle.” Waste can be categorized as products thrown off after use. They can be categorized into: Solid waste, Liquid waste, Scrap materials. They can further be classified into: Biodegradable and non-biodegradable.

      Waste Management often uses the “3 R strategy”:
      1. reduce

      The acceptable solid products for recycling include:
      1. Paper
      3.Aluminum and Steel Cans
      5.Corrugated Cardboard
      6.Plastic Grocery/Retail & Dry Cleaner Bags.

      Impact of recycling
      Recycling has a lower impact than producing new
      products from raw materials for all the waste items
      compared in this note. Both recycling and manufacture from raw
      materials affect the environment in several ways, for
      example through greenhouse gas emissions, pollution or
      the use of finite resources. For more info: refer http://www.wasteonline.org.uk

      What are the recycling facts and benefits?
      By recycling1 plastic bottle not only saves anywhere from 100 to 1000 years in the landfill but also saves the environment from the emissions in producing new bottles as well as the oil used to produce that bottle.

      For every1 ton of plastic that is recycled we save the equivalent of 2 people’s energy use for 1 year, the amount of water used by 1 person in 2 month’s time and almost 2000 pounds of oil.

      Today the most common products in cities recycling programs are paper products, cardboard, plastic, glass and aluminum.

      Approximately 60% of our rubbish thrown away today could be recycled.

      A survey was done and 9 out of 10 people surveyed said they would recycle more if it was easier. Odd as it seems there are many people who do not realize that plastic bottles our water comes in is made out of oil. This is the same oil that is used to make gasoline. It’s the same oil that is in such high demand and is not an unlimited resource.

    2. Recycling waste means processing the used the material into new products to prevent the wastage of potentially useful material, reduce consumption of fresh raw material, reduce energy usage, and reduce pollution of air, land and water usually by avoiding conventional methods of discarding waste.

      Advantages of recycling:
      – Energy consumed in recycling a product can be far less than used in fresh production e.g. Aluminum, paper(debatable as cost of paper collection for recycling if included, then energy consumption difference is marginal) etc.
      – Depletion of non-renewable natural resources can be delayed as raw material required will be less.
      – The recycling methods are far more cost effective as compared to production from virgin material.
      – This saves the landfill space
      – Surroundings remain cleaner and healthier.
      – Reduces the environmental impacts to be caused due to waste material disposal

      All these advantages can be exploited only if virgin the products are developed with a mindset of recycling post usage.

    1. The technique of using bacteria to get rid of oil spill is termed as ‘Oil Zapping’. The technique is developed by The Energy and Resource Institute (TERI), supported by Department of Biotechnology (Government of India). There are five different bacterial strains that are combined with a carrier material. This mixture of bacteria is called ‘Oil Zapper’. The bacteria feed on the hydrocarbon compounds in the crude oil and the hazardous hydrocarbons in the waste of oil refineries and convert them to harmless carbon dioxide and water.

    2. “Chitra spill: ‘oilzapper’ to be used for bioremediation”
      Source: The Hindu,Mumbai, August 22, 2010

      The new technique of using the bacteria to get rid of oil spill has been called “Oil Zapping”. Oil Zapping is a bio-remediation technique involving the use of ‘oil zapping’
      bacteria. It was recently employed to clean up the Mumbai shoreline affected by the oil spill that occurred in August 2010.

      The Mumbai Oil Spill happened when a merchant vessel M V Khalijia collided with a cargo ship MSC Chitra 10 km off the coast of Mumbai. MSC Chitra tilted 15 degrees soon after the collision but there was no loss of life. The cargo ship eventually tilted to about 80 degrees dropping around 250 containers into the sea. Before the spill could be plugged 400 tons of oil had leaked into the sea.

      The Maharashtra Pollution Control Board used the services of The Energy and Resources Institute (TERI) which has developed the oil zapping bacteria. TERI had developed this technique over a period of seven years. The Oil Zapping project was supported by the Department of Biotechnology (Government of India) and the Ministry of Science and Technology.

      There are five different bacterial strains that are immobilized and mixed with a carrier material such as “powdered corncob”. This mixture of five bacteria is called Oil
      Zapper. Oilzapper feeds on hydrocarbon compounds present in crude oil and the hazardous hydrocarbon waste generated by oil refineries, known as Oil Sludge and
      converts them into harmless Carbon dioxide and water. The Oilzapper is neatly packed into sterile polythene bags and sealed aseptically for safe transport. The shelf life of
      the product is three months at ambient temperature.
      The technique was used successfully and 130,000 tons of oily sludge/ oil contaminated soil was treated as per the leading news sources.

      1. Explaining in-situ and ex-situ methods for reference:

        In-situ conservation refers to conservation of species in natural habitats. On the other hand in ex-situ conservation biodiversity is preserved outside the natural habitats.
        It is considered that ex situ conservation measures should support in-situ conservation measures (in-situ conservation should be the primary objective).

        Out of given options, only a botanical garden is an ex-situ method of conservation of flora, rest all are in-situ conservation methods for flora as well as fauna.

    1. What are the emissions from coal combustion at thermal power plants?

      Based on the input parameters and the ultimate analysis of coal used for power generation, emissions of CO2, SO2, NO, soot carbon and particulate matter from each of the power plants has been computed. Input parameters (operating conditions) are actual air supplied, electric power generated per day, and coal used for unit power generation. Thermal power plants also use small quantities of diesel oil and furnace oil (FO) as supplementary fuels to boost the combustion and heat content. In the thermal power plants run by National Thermal Power Corporation (NTPC), supplementary fuel consumption is 0.2 to 0.3 ml/unit of power. The supplementary fuel consumption in old thermal power plants may range from 1 to 4% of the fuel. Emissions from combustion of these supplementary fuels are not accounted in the computations at present.

      further reference : http://www.osc.edu/research/archive/pcrm/emissions/thermalemissions.shtml

      For the estimation of emissions of above mentioned species from the Indian thermal power plants, the available values of the ultimate analysis of coals used in the seven thermal power plants namely Chandrapur, Dhanau, Singrauli, Dadri,Rihand, Kutch, and Nayveli, are used. Most of thermal power plants in India use E and F grade coals only. An average of ultimate analysis of E and F2 grade coals, is used for the remaining 74 thermal power plants. The excess air used in the individual power plants, kg coal used for unit (kwh) power generation, and per day power generation is available and is listed. NO calculations assume equilibrium reactions and 1700 K gas temperature.

      CO2 emissions are estimated based on the carbon content in the coal and the excess air used at the power plants. 12% carbon (based on the measurement data, it is assumed that 10% carbon remains unburned and mixes with the ash and 2% carbon forms soot) is subtracted before calculating emissions of CO2.

      The main emissions from coal combustion at thermal power plants are Carbon dioxide (CO2), Nitrogen oxides (NOx), Sulfur oxides (SOx), Chlorofluorocarbons (CFCs), carbonaceous material (soot), and air-borne inorganic particles such as fly ash, also known as suspended particulate matter (SPM) and other trace gas species. Carbon dioxide, nitrous oxide, and chlorofluorocarbons are greenhouse gases. Evidence accumulated by the Inter-governmental Panel on Climate Change (IPCC) suggests that emissions of these greenhouse gases might be responsible for climate change, a global concern. Possible consequences projected by IPCC include:
      – a rise in sea levels
      – a more vigorous hydrological cycle that may increase the severity of floods and droughts and may cause more extreme climatic events; and
      – ecological change that could threaten agricultural productivity

      Oxides of nitrogen and sulfur, also play an important role in atmospheric chemistry and are largely responsible for atmospheric acidity. Particulates and black carbon (soot) are of concern in the radiative10 forcing of the earth. They also have a significant negative impact on human health causing lung tissue irritation and are linked to cancer and other serious diseases.

      The pollutants emitted from thermal power plants depend largely upon the fuel burned, the furnace design, the excess air, and any additional devices used to reduce the emissions. At present, the only control device used in thermal power plants in India is electrostatic precipitator to control the emission of fly ash (SPM). CO2, SO2, nitric oxide (NO), soot, and SPM emissions from each of the thermal (coal-fired) power plants in India have been computed using basic principles of combustion. These calculations are based on a theoretical ideal and the input data, such as chemical composition of the coal used in the power plants, coal used per unit of power, excess air used during combustion, and the power generation from each plant. This input data has been collected from the published information. The present method to estimate the emissions is one of the many available methods for emissions inventory process. The other methods used in different countries are based on the guidelines recommended by IPCC11 , and may require large resources. Emissions from combustion of the supplementary fuels such as high-speed diesel (HSD) and furnace oil used in small quantities are not counted in the present calculations.

      Emission of carbon dioxide and sulfur dioxide:

      Utilities mostly burn coal with approximately 10 -30% excess air. Carbon as obtained from Ultimate analysis is converted to CO2 after the reaction (combustion) is complete. Some carbon is emitted in the form of soot and some carbon remains unburned and mixes with the ash. Different combustion technologies affect the types and concentrations of resultant species e.g. fixed bed combustion results in higher carbon content in the ash.

      Carbon in the coal is converted to carbon dioxide (CO2) by the reaction

      C + O2 –> CO2

      Similarly, hydrogen and sulfur are converted to moisture (H2O) and sulfur dioxide (SO2) by the reactions

      H2 + O2/2 –> H2O

      S + O2 –> SO2

      refernce: http://www.osc.edu/research/archive/pcrm/emissions/coalemissions.shtml

      Table 6A: Elemental analysis, moisture content, and grades of typical Indian coals refer : http://www.osc.edu/research/archive/pcrm/emissions/coal.shtml

      Methods of control of these emissions:
      1. Carbon capture and geological sequestration (CCS) is the key enabling technology for the
      reduction of CO2 emissions from coal based power generation. It is expected that CCS will
      become commercial for base load power generation around 2020-2025 following the
      construction and operation of several demonstration plants during the present and next

      2. Before the advent of commercial CCS technology options are available for high efficiency
      power generation with significantly reduced emissions of both CO2 and criteria pollutants.
      Prevalent among these options are:
      Pulverized coal combustion in ultra-supercritical steam cycle, and
      Integrated Coal gasification Combined gas turbine-steam Cycle (IGCC).

      1. Adding to Arun’s comment above on ways to control emission of hazardous gases:

        A carbon capture and storage (CCS) fossil plant already exists. Elsam power station near Esbjerg, Denmark is one such emission-less power plant.

        Pulverized coal is also called clean coal – Sulfur dioxide, other minerals and impurities can be removed by washing out chemically, sometimes gasified, burned and resulting flue gases treated with steam, and re-burned.

    1. 1. They use living organisms as catalysts to generate electricity from certain substrates.

      2. They can be installed in waste water treatment plants to cleanse water and produce electricity.

      Explain Microbial fuel cells

      1. Microbial Fuel Cell (MFC) is a device which converts chemical energy into electrical energy by the reaction of microorganisms acting as catalyst.
        MFC normally consists of a cathode and an anode separated by a membrane of cations. The fuel is oxidized by the microorganisms in the anode compartment and the electrons and protons are produced. The electrons get transferred to cathode through an external circuit, while protons travel through the membrane. Both get consumed in the cathode compartment and combined with oxygen to form water.

        Mostly the MFCs are electrochemically inactive. Electron transfer from cell to electrode needs a facilitator which are generally expensive as well as toxic e.g. thionine, methyl blue etc. Such cells are called mediator microbial fuel cell.
        A mediator free MFC uses electrochemically active bacteria to transfer electrons to electrode. Besides running on wastewater, such a cell can also draw its energy from aquatic plants. Such a cell gives an extra ecological advantage.

        These are called as source of sustainable energy as they do not require any non-renewable source of energy, and have advantages as explained above by the professor.

    2. Microbial fuel cells are not new – the concept of using
      microorganisms as catalysts in fuel cells was explored
      from the 1970s and microbial fuel cells treating
      domestic wastewater were presented in 1991.However,
      it is only recently that microbial fuel cells with an
      enhanced power output have been developed
      providing possible opportunities for practical applications.

      A MFC converts energy, available in a bio-convertible
      substrate, directly into electricity. This can be achieved
      when bacteria switch from the natural electron acceptor,
      such as oxygen or nitrate, to an insoluble acceptor, such as
      the MFC anode (Figure 1). This transfer can occur either
      via membrane-associated components, or soluble electron
      shuttles. The electrons then flow through a resistor to a
      cathode, at which the electron acceptor is reduced. In
      contrast to anaerobic digestion, a MFC creates electrical
      current and an off-gas containing mainly carbon dioxide.

      MFCs have operational and functional advantages over
      the technologies currently used for generating energy
      from organic matter:

      1. the direct conversion of
      substrate energy to electricity enables high conversion

      2. MFCs operate efficiently at ambient,
      and even at low, temperatures distinguishing them from
      all current bio-energy processes.

      3. an MFC does not
      require gas treatment because the off-gases of MFCs areenriched in carbon dioxide and normally have no useful
      energy content.

      4. MFCs have potential for widespread application in
      locations lacking electrical infrastructures and also to
      expand the diversity of fuels we use to satisfy our energy

      4. MFCs do not need energy input
      for aeration provided the cathode is passively aerated.


  3. Two important rivers — one with its source in Jharkhand (and known by a different name in Odisha), and another, with its source in Odisha — merge at a place only a short distance from the coast of Bay of Bengal before flowing into the sea. This is an important site of wildlife and biodiversity and a protected area. Which ls this?

    1. Bhitarkanika

      Gopalpur-on-sea in the Ganjam District of Orissa is famous for the sea turtles
      Chandipur on sea ia India’s Missile launching area. Sriharikota is another.

      Balasore (also known as Baleshwar) is a strategically located city in the state of Orissa, about 194 kilometres (121 mi) north of the state capital Bhubaneswar, in eastern India. It is the administrative headquarters of Balasore district. It is best known for Chandipur beach. It is also the site of the Indian Ballistic Missile Defense Program’s Integrated Test Range, located 18 km. south of Balasore. The Defence Research and Development Organisation developed many different missiles such as Nag, Brahmos, Agni missile among others here.

      The 2010 paper included Simlipal in the question as an option in addition to Gopalpur and Cahndipur. Simlipal National Park is a national park and an elephant reserve situated in the Mayurbhanj district in the Indian state of Orissa. Simlipal National Park derives its name from the abundance of Semul or red silk cotton trees that bloom vividly. Simlipal elephant reserve originated mainly as a hunting ground for the royalty. It was formally designated a tiger reserve in 1956 and under Project Tiger.

    1. Carbon credits are traded at a price fixed from time to time by the United Nations Environment Programme. India by adopting clean energy initiatives and by growing forests can reduce carbon emissions which lead to global warming and thus earn carbon credits.

    1. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth. It is one of the most important cycles of the earth and allows for carbon to be recycled and reused throughout the biosphere and all of its organisms.
      It is now usually thought of as including the following major reservoirs of carbon interconnected by pathways of exchange:
      • The atmosphere(photosynthesis, Animal Respiration, Soil respiration)
      • The terrestrial biosphere, which is usually defined to include fresh water systems and non-living organic material, such as soil carbon.
      • The oceans, including dissolved inorganic carbon and living and non-living marine biota,
      • The sediments including fossil fuels.
      • The Earth’s interior, carbon from the Earth’s mantle and crust is released to the atmosphere and hydrosphere by volcanoes and geothermal systems.

  4. A sandy and saline area is the natural habitat of an Indian animal species. The animal has no predators in that area but its existence is threatened due to the destruction of its habitat. Which one of the following could be that animal?

      1. The Indian wild ass, is with most other Asian wild ass subspecies, is quite different from the African species. The coat is usually sandy, but varies from reddish grey, fawn, to pale chestnut. The animal possesses an erect, dark mane which runs from the back of the head and along the neck. The mane is then followed by a dark brown stripe running along the back, to the root of the tail.

        Range/habitat :The Indian wild ass’s range once extended from western India, through Sindh and Baluchistan, Afghanistan, and south-eastern Iran. Today, its last refuge lies in the Indian Wild Ass Sanctuary, Little Rann of Kutch and its surrounding areas of the Greater Rann of Kutch in the Gujarat province. The animal, however, is also seen in the districts of Surendranagar, Banaskantha, Mehsana, and other Kutch districts. Saline desert, grassland in arid zone and shrubland are its preferred homeland.

  5. The 2004 Tsunami made people realize that mangroves can serve as a reliable safety hedge against coastal calamities. How do mangroves function as a safety hedge? Name the important mangroves in India.

    1. The mangrove swamps separate the human settlements from the sea by a wide zone in which people neither live nor venture out
      (b) The mangroves provide both food and medicines which people are in need of after any natural disaster
      (c) The mangrove trees are tall with dense canopies and serve as art excellent shelter during a cyclone or tsunami
      (d) The mangrove trees do not get uprooted by storms and tides because of their extensive roots

      Mangroves are survivors. With their roots submerged in water, mangrove trees thrive in hot, muddy, salty conditions that would quickly kill most plants, through a series of impressive adaptations—including a filtration system that keeps out much of the salt and a complex root system that holds the mangrove upright in the shifting sediments where land and water meet. Not only do mangroves manage to survive in challenging conditions, the mangrove ecosystem also supports an incredible diversity of creatures—including some species unique to mangrove forests. And, as scientists are discovering, mangrove swamps are extremely important to our own well-being and to the health of the planet.

  6. The formation of a thick brown cloud over Indian Ocean has been observed. This is the result of soot and sulphate aerosols emitted by burning fossil fuels. The soot in Asian Brown Cloud reflects sunlight and dims Earth below it but it also warms other places by absorbing incoming radiation and warming the atmosphere and whatever it touches. The sulphate aerosols on the other hand, although remain for shorter period of time in atmosphere than greenhouse gases, contribute to localized cooling and also degrade the air quality.

    The resulting regional concern include change in rainfall patterns in Asian monsoon, increased rainfall in northern Australia, rise in air temperature in elevated Himalayan region which would lead to water shortages and floods for millions of people who live downstream.
    Not just that, a study has found that the atmospheric brown clouds are producing weakening wind patterns which prevent wind shear patterns that historically have prohibited cyclones in Arabian Sea from becoming a major storm. Such phenomena have been observed in 2007 and 2010 in Gulf of Oman.

    In a study based on evolution of absolute environment impact of 179 countries, India has been ranked seventh most hazardous country in the world with carbon dioxide emission of 3000 pounds in 2007, and Brazil, US, China and Russia top the list.
    The developing as well as developed nations need to stop blaming one another, and join hands in fighting against upcoming environmental hazard. We need to find environment friendly alternatives for sulphate aerosol emitting fuels of factories, vehicles, poorly burnt biomass, and retrofitted CNG car engines.
    This can be only way to prevent the Third World War, this time by environment.

    1. The IUCN Red List of Threatened Species (also known as the IUCN Red List or Red Data List), founded in 1963, is the world’s most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature (IUCN) is the world’s main authority on the conservation status of species. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit.

      The IUCN Red List is set upon precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. The aim is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to try to reduce species extinction.

      Major species assessors include BirdLife International, the Institute of Zoology (the research division of the Zoological Society of London), the World Conservation Monitoring Centre, and many Specialist Groups within the IUCN Species Survival Commission (SSC). Collectively, assessments by these organizations and groups account for nearly half the species on the Red List.

      The IUCN aims to have the category of every species re-evaluated every five years if possible, or at least every ten years. This is done in a peer reviewed manner through IUCN Species Survival Commission (SSC) Specialist Groups, which are Red List Authorities responsible for a species, group of species or specific geographic area, or in the case of BirdLife International, an entire class (Aves).

      In 2007 release On 12 September 2007, the World Conservation Union (IUCN) released the 2007 IUCN Red List of Threatened Species. In this release, they have raised their classification of both the Western Lowland Gorilla and the Cross River Gorilla.

      2008 releaseThe 2008 Red List was released on 6 October 2008, at the IUCN World Conservation Congress in Barcelona, and “has confirmed an extinction crisis, with almost one in four [mammals] at risk of disappearing forever”. The study shows at least 1,141 of the 5,487 mammals on Earth are known to be threatened with extinction.

      2006 IUCN Red List categories.
      Species are classified in nine groups,,

      Extinct (EX) -no individuals remaining .
      Extinct in the Wild (EW) – Known only to survive in captivity, or as a naturalized population outside its historic range.
      Critically Endangered (CR) – Extremely high risk of extinction in the wild.
      Endangered (EN) – High risk of extinction in the wild.
      Vulnerable (VU) – High risk of endangerment in the wild.
      Near Threatened (NT) – Likely to become endangered in the near future.
      Least Concern (LC) – Lowest risk. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category.
      Data Deficient (DD) – Not enough data to make an assessment of its risk of extinction.
      Not Evaluated (NE) – Has not yet been evaluated against the criteria.
      When discussing the IUCN Red List, the official term “threatened” is a grouping of three categories: Critically Endangered, Endangered, and Vulnerable.

      The older 1994 has only a single “Lower Risk” category which contained three subcategories:

      Conservation Dependent
      Near Threatened
      Least Concern
      In the 2001 system, Near Threatened and Least Concern have now become their own categories, while Conservation Dependent is no longer used and has been merged into Near Threatened.

    2. The main purpose of the IUCN Red List is to catalogue and highlight those plants and animals that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on plants and animals that are categorized as Extinct or Extinct in the Wild; on taxa that cannot be evaluated because of insufficient information (i.e., are Data Deficient); and on plants and animals that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e., are Near Threatened).

    1. The most important greenhouse gas, apart from water vapour, is carbon dioxide (CO2). Levels have changed over time both naturally and because of humans. Much of the carbon dioxide produced by humans does not stay in the atmosphere but is stored in the oceans or on land in plants and soils. By far the largest carbon store on Earth is in sediments, both on land and in the oceans, and it is held mainly as calcium carbonate (CaCO3). The second biggest store is the deep ocean where carbon occurs mostly as dissolved carbonate (CO32-) and hydrogen carbonate ions (HCO3-). It is about a third of the carbon dioxide from fossil fuel burning is stored in the oceans and it enters by both physical and biological processes.

      As the carbon is heavier than air, not much of carbon dioxide escapes to stratosphere.

  7. With reference to India, consider the following Central Acts:
    1. Import and Export (Control) Act, 1947
    2. Mining and Mineral Development (Regulation) Act, 1957
    3. Customs Act, 1962
    4. Indian Forest Act, 1927

  8. 27. A layer in the Earth s atmosphere called Ionosphere facilitates radio communication. Why?
    1. The presence of ozone ’causes the,reflection of radio waves to Earth.
    2. Radio waves have a very long wavelength

    Which of the statements given above is/are correct.
    a) 1 Only
    b) 2 only
    c) Both 1 and 2
    d) Neither 1 nor 2

  9. Consider the foliowing:
    1. Photosynthesis
    2. Respiration
    3. Decay of organic matter
    4. Volcanic action

    Which of the above add carbon dioxide to the carbon cycle on Earth ?
    (a) 1 and 4 only
    (b) 2 and 3 only
    (c) 2, 3 and 4 only
    (d) 1, 2,3 and 4

  10. Biodiversity forms the basis for human existence in the following ways:
    1. Soil formation
    2. Prevention of soil erosion
    3. Recycling of waste
    4. Pollination of crops
    Select the correct answer using the codes given below:
    (a) 1, 2 and 3 only
    (b) 2, 3 and 4 only
    (c) 1 and 4 only
    (d) 1, 2, 3 and 4

  11. 61. Biodiversity forms the basis for human existence in the following ways:
    1. Soil formation
    2. Prevention of soil erosion
    3. Recycling of waste
    4. Pollination of crops
    Select the correct answer using the codes given below:
    (a) 1, 2 and 3 only
    (b) 2, 3 and 4 only
    (c) 1 and 4 only
    (d) 1, 2, 3 and 4

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.