Unit IX - Plant Ecology Chapter 8 Environmental Issues

Learning Objectives 8.9 Rain water harvesting 8.10 Sewage disposal Learning objectives 8.11 Environmental Impact Assessment Th e learner will be able to, (EIA) Understand the importance of growing more plants to mitigate the Aft er understanding the structure and functions environmental problems. of major ecosystems of the world, now student Distinguish between the importance community should observe and understand and conservation of endemic and environmental problems of their surroundings endangered species. at local, national and international level. Appreciate the use of technologies for Now we are going to understand some of the agriculture and forestry. environmental issues such as Participate in community activities to Over population improve environmental conditions. Develop methods in conservation Health issues of water and plants for sustainable Waste disposal development. All types of pollution Get acquainted with satellite Green House gases technology and utilising it in our daily Ozone depletion life needs Water, energy, food scarcity De-forestation Chapter outline Climate change Industrialisation, 8.1 Green house eff ect, urbanisation impacts ozone depletion 8.2 Forestry Figure 8.1: Environmental issues 8.3 Deforestation 8.4 Aff orestation Environmental issues are the problems and 8.5 Agrochemicals and harmful eff ects created by human’s unmindful their eff ects activity and over utilisation of valuable resources 8.6 Alien invasive species obtained from the nature (environment). Student 8.7 Conservation should understand not only the environmental 8.8 Carbon Capture and Storage (CCS) issues we are facing now, but also fi nd solutions to rectify or reduce these problems.

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 191 01-03-2019 17:00:50 Countries of the whole world agree that in major ecosystems and climate patterns. For something needs to be done about these important example, coral ecosystem is affected by increase environmental issues. Many global summits, in temperature, especially coral bleaching conferences and conventions are regularly observed in Gulf of Mannar, . conducted by the United Nations and many steps Human activities lead to produce the green are taken to minimise human-induced issues by house effect by

signing agreements with around 150 countries. • Burning fossil fuels, which releases CO2 and

CH4 Activity 1 • Way of Agriculture and animal husbandry Students may form ‘ECOGROUPS’ and practices discuss eco-issues of their premises and find • Electrical gadgets like refrigerator and air solutions to the existing problems like, litter conditioners release chloro fluoro carbons disposal, water stagnation, health and hygiene, • The fertilizers used in Agriculture which

greening the campus and its maintenance. release N2O • The emissions from automobiles. Drastic increase in population resulted The increase in mean global temperature (highest in demand for more productivity of food in 4000 years) due to increased concentration of materials, fibres, fuels which led to many green house gases is called global warming. environmental issues in agriculture, land use modifications resulting in loss of biodiversity, One of the reasons for this is over population land degradation, reduction in fresh water which creates growing need for food, fibre and availability and also resulting in man-made fuel and considered to be the major cause of global warming by green house gases even global warming. altering climatic conditions. Clouds and Dust particles can also produce Green House 8.1 Green House effect and Global effect. That is why clouds, Warming dusts and humid nights are Green House Effect is a process by which warmer than clear dust free dry nights. radiant heat from the sun is captured by gases in the atmosphere 8.1.1. Effects of Global Warming that increase the • Rise in global temperature which causes sea CH temperature of the 4 20% levels to rise as polar ice caps and glaciers earth ultimately. begin to melt causing submergence of many CFC CO2 The gases that 14% 60% Others 6% coastal cities in many parts of the world. capture heat are • There will be a drastic change in weather called Green patterns bringing more floods or droughts House Gases which in some areas. include carbon Figure 8.2: Relative contribution of green • Biological diversity may get modified, dioxide (CO2), house gases some species ranges get redefined. Tropics methane (CH , 4) and sub-tropics may face the problem of Nitrous Oxide decreased food production. (N2O) and a variety of manufactured chemicals like chlorofluorocarbon (CFC). Increase in greenhouse gases lead to irreversible changes

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 192 01-03-2019 17:00:50 8.1.2. Sources of Green House Gases • Developing alternate renewable sources of Emission (Natural and Anthropogenic) energy • Minimising uses of nitrogeneous fertilizers, CO2 (Carbon dioxide) and aerosols. • Coal based power plants, by the burning of fossil fuels for electricity generation. 8.1.4. Ozone depletion •Combustion of fuels in the engines of Ozone layer is a region of Earth’s stratosphere that automobiles, commercial vehicles and air absorbs most of the Sun’s ultra violet radiation. planes contribute the most of global warming. Th e ozone layer is also called as theozone shield • Agricultural practices like stubble burning and it acts as a protective shield, cutting the ultra- violet radiation emitted by the sun. result in emission of CO2. •Natural from organic matter, volcanoes, Just above the atmosphere there are two warm oceans and sediments. layers namely troposphere (the lower layer) and stratosphere (the upper layer). Th e ozone Methane layer of the troposphere is called bad ozone Methane is 20 times as eff ective as CO2 at and the ozone layer of stratosphere is known as trapping heat in the atomosphere. Its sources good ozone because this layer acts as a shield are attributed paddy cultivation, cattle rearing, for absorbing the UV radiations coming from bacteria in water bodies, fossil fuel production, the sun which is harmful for living organisms ocean, non-wetland soils and forest / wild fi res. N O (Nitrous oxide) 2 Ozone is a colourless gas, reacts readily with It is naturally produced in Oceans from biological air pollutants and cause rubber to crack, hurt sources of soil and water due to microbial actions plant life, damages lung tissues. But ozone and rainforests. Man-made sources include nylon absorbs harmful ultra violet β (uv-β) and UV – and nitric acid production, use of fertilizers in α radiation from sunlight. agriculture, manures cars with catalytic converter What is Dobson Unit? DU is the unit of and burning of organic matter. measurement for total ozone. One DU (0.001 Global Warming Eff ects on Plants atm. cm) is the number of molecules of ozone • Low agricultural productivity in tropics that would be required to create a layer of pure • Frequent heat waves (Weeds, pests, fungi ozone 0.01 millimetre thick at a temperature of need warmer temperature) 0° C and a pressure of 1 atmosphere (atm = the • Increase of vectors and epidemics air pressure at the surface of earth). Total ozone • Strong storms and intense fl ood damage layer over the earth surface is 0.3 centrimetres • Water crisis and decreased irrigation (3 mm) thick and is written as 300 DU. • Change in fl owering seasons and pollinators Th e false colour • Change in Species distributional ranges view of total ozone • Species extinction - Th e purple and blue colours are 8.1.3 Strategies to deal with Global Warming where there is the •Increasing the vegetation cover, grow more least ozone, and the trees yellows and reds are • Reducing the use of fossil fuels and green where there is more ozone. Figure 8.3: Th e false house gases colour view of total ozone

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 193 01-03-2019 17:00:50 causing DNA damage. The thickness of the Clean Development Mechanism (CDM) ozone column of air from the ground to the is defined in the Kyoto protocol (2007) which top of the atmosphere is measured in terms of provides project based mechanisms with two Dobson Units. objectives to prevent dangerous climate change The ozone shield is being damaged by and to reduce green house gas emissions. CDM chemicals released on the Earth’s surface projects helps the countries to reduce or limit notably the chlorofluorocarbons widely used emission and stimulate sustainable development. in refrigeration, aerosols, chemicals used as An example for CDM project activity, is cleaners in many industries. The decline in the replacement of conventional electrification thickness of the ozone layer over restricted area projects with solar panels or other energy is called Ozone hole. efficient boilers. Such projects can earn Certified Emission Reduction (CER) with credits / scores, September 16 is WORLD OZONE DAY each equivalent to one tonne of CO2, which can Ozone depletion in the stratosphere be counted towards meeting Kyoto targets. results in more UV radiations especially UV B Plant indicators radiations (shortwaves). UV B radiation destroys The presence or absence of certain biomolecules (skin ageing) and damages living plants indicate the state of environment tissues. UV – C is the most damaging type of by their response. The plant species or UV radiation, but it is completely filtered by the plant community acts as a measure of atmosphere (ozone layer). UV – a contribute 95% environmental conditions, it is referred as of UV radiation which causes tanning burning biological indicators or phytoindicators or of skin and enhancing skin cancer. Hence the plant indicators. uniform ozone layer is critical for the wellbeing of life on earth. Examples During 1970’s research findings indicated Plants Indicator for that man-made chlorofluorocarbons (CFC) 1 Lichens, Ficus, Pinus, SO2 pollution Rose reduce and convert ozone molecules in the 2. Petunia, Nitrate atmosphere. The threats associated with reduced Chrysanthemum ozone pushed the issue to the forefront of global 3. Gladiolus Flouride climate issues and gained promotion through pollution organisation such as World Meterological 4. Robinia pseudoacacia Indicator of Organisation and the United Nations. The (Black locust tree) heavy metal contamination Vienna Convention was agreed upon at the Vienna conference of 1985 but entered into force 8.1.5 Effects of Ozone depletion in 1988 provided the frameworks necessary to create regulative measures in the form of the The main ozone depletion effects are: Montreal protocol. The International treaty • Increases the incidence of cataract, throat called the Montreal Protocol (1987) was held in and lung irritation and aggravation of Canada on substances that deplete ozone layer asthma or emphysema, skin cancer and and the main goal of it is gradually eliminating diminishing the functioning of immune the production and consumption of ozone system in human beings. depleting substances and to limit their damage • Juvenile mortality of animals. on the Earth’s ozone layer. • Increased incidence of mutations.

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 194 01-03-2019 17:00:51 • In plants, photosynthetic chemicals will be • Multipurpose tree varieties like Acacia are affected and therefore photosynthesis will used for wood pulp, tanning, paper and be inhibited. Decreased photosynthesis will firewood industries. result in increased atmospheric CO2 resulting • Agro-forestry is recommended for the in global warming and also shortage of food following purposes. It can be used as leading to food crisis. Farm Forestry for the extension of forests, • Increase in temperature changes the climate mixed forestry, shelter belts and linear strip and rainfall pattern which may result in plantation. flood / drought, sea water rise, imbalance in Rehabilitation of degraded forests and ecosystems affecting flora and fauna. recreation forestry 8.2 Forestry The production of woody plants combined with pasture is referred to silvopasture system. 8.2.1 Agro forestry The trees and shrubs may be used primarily Agroforestry is an integration of trees, crops to produce fodder for livestock or they may and livestock on the same plot of land. The main be grown for timber, fuel wood and fruit or to objective is on the interaction among them . improve the soil. Example: intercropping of two or more crops This system is classified into following categories. between different species of trees and shrubs, i. Protein Bank: In this various multipurpose which results in higher yielding and reducing the trees are planted in and around farm operation costs. This intentional combination lands and range lands mainly for fodder of agriculture and forestry has varied benefits production. including increased bio-diversity and reduced Example: Acacia nilotica, Albizzia lebbek, erosion. Azadirachta indica, Gliricidia sepium, Some of the major species cultivated in Sesbania grandiflora. commercial Agroforestry include Casuarina, ii. Livefence of fodder trees and hedges: Eucalyptus, Malai Vembu, Teak and Kadambu Various fodder trees and hedges are planted trees which were among the 20 species as live fence to protect the property from identified as commercial timber. They are of stray animals or other biotic influences. great importance to wood-based industries. Example: Gliricidia sepium, Sesbania Benefits of agroforestry grandiflora, Erythrina spp., Acacia spp.. • It is an answer to the problem of soil and water conservation and also to stabilise 8.2.2 Social forestry the soil (salinity and water table) reduce It refers to the sustainable management of landslide and water run-off problem. forests by local communities with a goal • Nutrient cycling between species improves of climate carbon sequestration, change and organic matter is maintained. mitigation, depollution, deforestation, forest restoration and providing indirect employment • Trees provide micro climate for crops and opportunity for the youth. Social forestry refers maintain O2 – CO2 balanced, atmospheric to the management of forests and afforestation temperature and relative humidity. on barren lands with the purpose of helping the • Suitable for dry land where rainfall is environmental, social and rural development minimum and hence it is a good system for and benefits. Forestry programme is done alternate land use pattern. for the benefit of people and participation of

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 195 01-03-2019 17:00:51 the people. Trees grown outside forests by cause of deforestation. government and public organisation reduce the • Logging for timber pressure on forests. • Developmental activities like road In order to encourage tree cultivation outside construction, electric tower lines and dams. forests, Tree cultivation in Private Lands was • Over population, Industrialisation, implemented in the state from 2007-08 to 2011- urbanisation and increased global needs. 12. It was implemented by carrying out block Effects of deforestation planting and inter-crop planting with profitable tree species like Teak, Casuarina, Ailanthus, • Burning of forest wood release stored Silver Oak, etc. in the farming lands and by a carbon, a negative impact just opposite of free supply of profitable tree species for planting carbon sequestration. in the bunds. The Tank foreshore plantations • Trees and plants bind the soil particles. The have been a major source of firewood in Tamil removal of forest cover increases soil erosion Nadu. The 32Forestry extension centres and decreases soil fertility. Deforestation in provide technical support for tree growing in dry areas leads to the formation of deserts. rural areas in Tamil Nadu. These centres provide • The amount of runoff water increases soil quality tree seedlings like thorn / thornless erosion and also creates flash flooding, thus bamboo, casuarinas, teak, neem, Melia dubia, reducing moisture and humidity. grafted tamarind and nelli, etc. in private lands • The alteration of local precipitation patterns and creating awareness among students by leading to drought conditions in many training / camps. regions. It triggers adverse climatic conditions 8.2.3. Major activities of forestry and alters water cycle in ecosystem. extension centres • It decreases the bio-diversity significantly as • Training on tree growing methods their habitats are disturbed and disruption of natural cycles. • Publicity and propaganda regarding tree growing • Loss of livelihood for forest dwellers and rural people. • Formation of demonstration plots • Increased global warming and account for • Raising and supply of seedlings on subsidy one-third of total CO2 emission. • Awareness creation among school children • Loss of life support resources, fuel, medicinal and youth about the importance of forests herbs and wild edible fruits. through training and camps. 8.4 Afforestation 8.3 Deforestation Afforestation is planting of trees where there was Deforestation is one of the major contributors no previous tree coverage and the conversion to enhance green house effect and global of non-forested lands into forests by planting warming. The conversion of forested area into suitable trees to retrieve the vegetation. Example: a non-forested area is known as deforestation. Slopes of dams afforested to reduce water run- Forests provide us many benefits including off, erosion and siltation. It can also provide goods such as timber, paper, medicine and a range of environmental services including industrial products. The causes are carbon sequestration, water retention. • The conversion of forests into agricultural plantation and livestock ranching is a major

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 196 01-03-2019 17:00:51 The Man who Single Handedly Created a Achievements Dense Forest • Degraded forests were restored Jadav "Molai" Payeng (born 1963) is an • Community assets like overhead tanks environmental activist has single-handedly bore-wells, hand pumps, community halls, planted a forest in the middle of a barren libraries, etc were established wasteland. This Forest Man of has • Environmental and ecological stability was transformed the world’s largest river island, maintained. Majuli, located on one of India’s major rivers, • Conserved bio-diversity, wildlife and genetic the Brahmaputra, into a dense forest, home to resources. rhinos, deers, elephants, tigers and birds. And • Involvement of community especially today his forest is larger than Central Park. women in forest management. Former vice-chancellor of Jawahar Lal Nehru University, Sudhir Kumar Sopory Case study named Jadav Payeng as Forest Man of Tamil Nadu Afforestation Project (TAP) India, in the month of October 2013. He was With an aim of ecological restoration and honoured at the Indian Institute of Forest biological up-gradation of degraded forests Management during their annual event and other lands, the government of Tamil ‘Coalescence’. In 2015, he was honoured Nadu launched the project in 2 phases with Padma Shri, the fourth highest civilian Tap I (1997-2005). It aimed to uplift the award in India. He received honorary quality and life of villagers abutting forest doctorate degree from Assam Agricultural areas and to resolve the degraded forests in University and Kaziranga University for his Tamil Nadu. This is a massive Joint Forest contributions. Management Programme. TAP II (2005- Afforestation Objectives 2013) had 2 main objectives. • To increase forest cover, planting more trees, • To restore the ecological equilibrium

increases O2 production and air quality. of the forests, watersheds and adjacent • Rehabilitation of degraded forests to villages of Tamil Nadu.

increase carbon fixation and reducing CO2 • To improve the quality of the life of from atmosphere. inhabitants through reforestation, water • Raising bamboo plantations. conservation and sustained community action. • Mixed plantations of minor forest produce and medicinal plants. • Regeneration of indigenous herbs / shrubs. • Awareness creation, monitoring and A B evaluation. Figure 8.4: Constructions under TAP • To increase the level and availability of water A. Check Dam B. Percolation pond table or ground water and also to reduce nitrogen leaching in soil and nitrogen contamination of drinking water, thus 8.5 Agrochemicals and their effects making it pure not polluted with nitrogen. An agro-chemical is useful in managing • Nature aided artificial regeneration. agriculture or in farming area which is one of the major issues of the environment. Agro-

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 197 01-03-2019 17:00:51 chemicals includes fertilizers, liming and reduce native herbs, thus reducing the ecosystem acidifying agents, soil conditioners, pesticides services (benefits). During eradication of and chemicals used in animal husbandry, such these species, the chemicals used increases as antibiotics and hormones. greenhouse gases. Slowly they alter ecosystem, Excessive use of fertilizers and pesticides micro climate and nature of soil and make it leads to the contamination of groundwater and unsuitable for native species and create human makes it nonpotable, ultimately affecting the soil health problems like allergy, thus resulting in fertility. Most of the chemical fertilizers contain local environmental degradation and loss of varying amounts of nitrogen, phosphorous, important local species. potassium and nutrients that plants need to According to World Conservation Union grow. Soil acidity influences C and N cycles by invasive alien species are the second most affecting soil microbes, also green house gas flux significant threat to bio-diversity after habitat loss. in soils and affect bio availability of N, P, S like What is invasive species? major nutrients. This makes the soil too acidic A non-native species to the ecosystem or country or alkaline so that it becomes difficult for the under consideration that spreads naturally, plants to survive. These residues and synthetic interferes with the biology and existence of chemicals like DDT (dichloro diphenyl trichloro native species, poses a serious threat to the ethane) and PCBs (polychlorinated biphenyls) ecosystem and causes economic loss. cause nutrient and pH imbalance and quality It is established that a number of invasive reduction of agricultural produce. This problem species are accidental introduction through can be minimised by sustainable agriculture. ports via air or sea. Some research organisations Pesticides increase incidence of brain, blood import germplasm of wild varieties through cancer and neurotoxicity, Parkinson like which also it gets introduced. Alien species with symptoms, infertility, birth defects, reproductive edible fruits are usually spread by birds. and behavioural disorders. Invasive species are fast growing and are • Nitrates from fertilizers more adapted. They alter the soil system by interact with the haemoglobin changing litter quality thereby affecting the to form methyl haemoglobin. soil community, soil fauna and the ecosystem This reduces oxygen uptake, processes. results in Blue baby syndrome (cyanosis) It has a negative impact on decomposition and hypoxia. Nitrates vasodilate and reduce in the soils by causing stress to the neighbouring blood pressure. native species. Some of the alien species which • Bio-magnification: Pollutants, toxic cause environmental issues are discussed below substances increase in water move from one Eichhornia food chain to many and finally reach human crassipes being and this process of bio-amplification It is an invasive or increase in concentration is called weed native to bio-magnification. South America. It was introduced 8.6 Alien invasive species as aquatic Figure 8.5: Invasion of alien or introduced species disrupts ornamental Eichhornia crassipes ecosystem processes, threaten biodiversity, plant, which grows faster throughout the year. Its widespread

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 198 01-03-2019 17:00:53 growth is a major cause of biodiversity It infests pastures and farmland causing often loss worldwide. It affects the growth of loss of yield. The plant produces allelopathic phytoplanktons and finally changing the aquatic chemicals that suppress crop and native plants ecosystem. and its pollen causes allergic rhinitis and It also decreases the oxygen content of the asthma, dermatitis in humanbeing. waterbodies which leads to eutrophication. It Prosopis juliflora poses a threat to human health because it creates a Prosopis juliflora breeding habitat for disease causing mosquitoes is an invasive (particularly Anopheles) and snails with its species native to free floating dense roots and semi submerged Mexico and South leaves. It also blocks sunlight entering deep and America. It was the waterways hampering agriculture, fisheries, first introduced in recreation and hydropower. Gujarat to counter Lantana camara desertification Figure 8.8: Prosopis juliflora Identified as one of the and later on in worst invasive species Andhra Pradesh, by Global Invasive Tamil Nadu as a source of firewood. It is an Species Database. It aggressive coloniser and as a consequence the is also an invasive habitats are rapidly covered by this species. Its weed native to South Figure 8.6: invasion reduced the cover of native medicinal America introduced Lantana camara herbaceous species. It is used to arrest wind as ornamental plant. erosion and stabilize sand dunes on coastal and It occupies a widely adaptable range of habitats. desert areas. It can absorb hazardous chemicals This species is spread by birds It exerts from soil and it is the main source of charcoal. allelopathic effect, which reduces the growth of 8.7 Conservation surrounding plants by inhibiting germination and root elongation. Root removal and bio- India due to its topography, geology and control are the best methods to control. Now climate patterns has diverse life forms. Now tribes are trained to use the stem as fibre for this huge diversity is under threat due to many making household materials like baskets, environmental issues for this conservation furniture and even cots. becomes an important tool by which we can reduce many species getting lost from our native Parthenium hysterophorus land. By employing conservation management Parthenium hysterophorus native to South strategies like germplasm conservation, in situ, America introduced accidently into many ex-situ, in-vitro methods, the endemic as well regions of the world along with imported as threatened species can be protected food grains. It is a harmful weed in In-situ conservation the forest which It means conservation and management of suppresses the genetic resources in their natural habitats. Here growth of native the plant or animal species are protected within species and reduces the existing habitat. Forest trees, medicinal and aromatic plants under threat are conserved the availability of Figure 8.7: Parthenium by this method. This is carried out by the fodder for animals hysterophorus

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 199 01-03-2019 17:00:53 Bio-diversity Conservation

In-situ Ex-situ

Protected area Sacred plants Seed banks, Pollen Botanical gardens network home gardens banks, Field gene, Arboreta, Zoological Cryopreservation parks, Aquaria Community Government Protected Protected

Sacred groves Biosphere Wildlife Sacred lakes National parks Reserves Sanctuaries

Terrestial Marine Figure 8.9: Flow chart on biodiversity conservation

community or by the State conservation which Ex-situ conservation include wildlife, National park and Biosphere It is a method of conservation where species are reserve. The ecologically unique and biodiversity protected outside their natural environment. rich regions are legally protected as wildlife This includes establishment of botanical gardens, sanctuaries, National parks and Biosphere zoological parks, conservation strategies such reserves. Megamalai, Sathyamangalam wildlife, as gene, pollen, seed, in-vitro conservation, and Periyar National park, and Western cryo preservation, seedling, tissue culture and ghats, Nilgiris, Agasthyamalai and Gulf of DNA banks. These facilities not only provide Mannar are the biosphere reserves of Tamil housing and care for endangered species, but Nadu. also have educational and recreational values Sacred groves for the society These are the patches or grove of cultivated trees 8.7.1 International Union for which are community protected and are based Conservation of Nature (IUCN) on strong religious belief systems which usually Founded in 1948, the International Union for have a significant religious connotation for Conservation of Nature (IUCN) is the world’s protecting community. Each grove is an abode oldest environmental organisation with its of a deity mostly village God Or Goddesses headquarters at Gland, Switzerland. It is a neutral like Aiyanar or Amman. 448 grooves were forum for Governments, NGO’s, Scientists, documented throughout Tamil Nadu, of which business and local communities with the aim of 6 groves (Banagudi shola, Thirukurungudi and developing solution and implementing policies Udaiyankudikadu, Sittannnavasal, Puthupet related to the conservation of environment and and Devadanam) were taken up for detailed sustainable development. floristic and faunistic studies. These groves provide a number of ecosystem services to IUCN Red List the neighbourhood like protecting watershed, IUCN Red List categories help us to evaluate the fodder, medicinal plants and micro climate degree of threat and conservation priorities to control. the flora and fauna It is also a powerful tool for

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 200 01-03-2019 17:00:53 Conservation movement A - Population reduction B - Geographic range A community level participation can help C - Small population size and decline in preservation and conservation of our D - Very small or restricted population environment. Our environment is a common E - Quantitative analysis treasure for all the living organisms on earth. Every individual should be aware of this and Erlinct (Ex) + participate actively in the programs meant for Extinct in the wild (EW)

the conservation of the local environment. Threatened species

Indian history has witnessed many people Adequate data movements for the protection of environment. Critically endangered Chipko Movement Endangered EN

Evaluated Vulnerable VU

The tribal women of Himalayas protested Extinction risk against the exploitation of forests in 1972. Later on it transformed into Chipko Movement by Near threatened (NT)

Sundarlal Bahuguna in Mandal village of Least concerned (LC) Chamoli district in 1974. People protested All species by hugging trees together which were felled Data Deficient (DD) –

by a sports goods company. Main features of Not evaluated (NE) Chipko movement were, Figure 8.10: IUCN Red List categories • This movement remained non political IUCN Red List categories • It was a voluntary movement based on Gandhian thought. Extint (EX) • It was concerned with the ecological balance A taxon is Extinct when there is no reasonable of nature doubt on the death of the last individual. A • Main aim of Chipko movement was to give a taxon is presumed Extinct when exhaustive slogan of five F’s – Food, Fodder, Fuel, Fibre surveys in known and/or expected habitat, at and Fertilizer, to make the communities self appropriate times (diurnal, seasonal, annual), sufficient in all their basic needs. throughout its historic range have failed to record an individual. Example: Neuracanthus Appiko Movement neesianus. The famous Chipko Andolen of Uttarakhand Extinct in the wild (EW) in the Himalayas inspired the villagers of Uttar Karnataka to launch a similar movement to save A taxon is Extinct in the Wild when it is known their forests. This movement started in Gubbi only to survive in cultivation, in captivity or as Gadde a small village near Sirsi in Karnataka a naturalised population (or populations) well by Panduranga Hegde. This movement started outside the past range. Example: Ginkgo biloba to protest against felling of trees, monoculture, Critically endangered (CR) forest policy and deforestation. A taxon is Critically Endangered when the best available evidence indicates that it meets any of persuading governments to protect threatened the criteria A to E for Critically Endangered, species and for most of the plant and animal and it is therefore considered to be facing an species world-wide. IUCN has developed extremely high risk of extinctions in the wild. protected areas and developed criteria for Example: Euphorbia santapaui, Piper barberi, threatened species. The criteria are as follows . Syzygium gambelianum.

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 201 01-03-2019 17:00:53 Endangered (EN) 8.7.2 Endemic Centres and Endemic A taxon is Endangered when the best available Plants evidence indicates that it meets any of the Endemic species are plants and animals that criteria A to E for Endangered, and it is therefore exist only in one geographic region. Species can considered to be facing a very high risk of be endemic to large or small areas of the earth. extinction in the wild. Example: Elaeocarpus Some are endemic to a particular continent, venustus, Pogostemon nilagricus, Eugenia some to a part of a continent and others to a singampattiana. single island. Vulnerable (VU) Any species found restricted to a specified A taxon is Vulnerable when the best available geographical area is referred to as ENDEMIC.. evidence indicates that it meets any other It may be due to various reasons such as criteria A to E for Vulnerable, and it is therefore isolation, interspecific interactions, seeds considered to be facing a high risk of extinction dispersal problems, site specificity and many in the wild. Example: Dalbergia latifolia, other environmental and ecological problems. Santalum album, Chloroxylon sweitenia There are 3 Megacentres of endemism and 27 microendemic centres in India. Approximately Near threatened (NT) one third of Indian flora have been identified as A taxon is Near Threatened when it has been endemic and found restricted and distributed in evaluated against the criteria but does not three major phytogeographical regions of india, qualify for Critically Endangered, Endangered that is Indian Himalayas, Peninsular India and or Vulnerable now, but is close to qualifying for Andaman nicobar islands. Peninsular India, or is likely to qualify for threatened category in especially Western Ghats has high concentration the near future. of endemic plants. Hardwickia binata and Least concerned (LC) Bentinckia condapanna are good examples for endemic plants. A large percentage of Endemic A taxon is Least Concerned when it has been species are herbs and belong to families such as evaluated against the criteria and does not Poaceae. Apiaceae, Asteraceae and Orchidaceae. qualify for Critically Endangered, Endangered, Vulnerable or Near Threatened, Widespread Endemic plants Habit Name of endemic centre Baccaurea Tree Southern Western and abundant taxa are included in this category. courtallensis Ghats Data deficient (DD) Agasthiyamalaia Tree Peninsular india A taxon is Data Deficient when there is inadequate pauciflora Hardwickia Tree Peninsular and information to make a direct, or indirect, binata northern India assessment of the risk of extinction based on its Bentinckia Tree Western ghats of Tamil distribution and/or population status. condappana Nadu and kerala Not evaluated (NE) Nepenthes Liana Khasi hills, Meghalaya khasiyana A taxon is Not Evaluated when it has not yet been evaluated against the criteria. Table 1: Endemic plants Majority of endemic species are threatened due to their narrow specific habitat, reduced seed production, low dispersal rate, less viable nature and human intereferences.. Serious efforts need to be undertaken for their conservation, otherwise these species may become globally extinct.

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 202 01-03-2019 17:00:53 Carbon Sequestration Carbon sequestration is the process of capturing and storing CO2 which reduces the amount of CO2 in the atmosphere with a goal of reducing global climate change. a b Carbon sequestration occurs naturally by plants Figure 8.11: Endemic Plants and in ocean. Terrestrial sequestration is typically a. Bentinckia condapanna b. Baccaurea courtallensis accomplished through forest and soil conservation practices that enhance the storage carbon. 8.8 Carbon Capture and Storage (CCS) As an example microalgae such as species Carbon capture and storage is a technology of of Chlorella, Scenedesmus, Chroococcus and

capturing carbondioxide and injects it deep into Chlamydomonas are used globally for CO2 the underground rocks into a depth of 1 km or sequestration. Trees like Eugenia caryophyllata, more and it is an approach to mitigate global Tecomastans, Cinnamomum verum have warming by capturing CO2 from large point high capacity and noted to sequester carbon sources such as industries and power plants macroalgae and marine grasses and mangroves and subsequently storing it instead of releasing are also have ability to mitigate carbon-di-oxide. it into the atmosphere. Various safe sites have Carbon Foot Print (CFP) been selected for permanent storage in various deep geological formations, liquid storage in the Every human activity leaves a mark just like our footprint. This Carbon foot print is the Ocean and solid storage by reduction of CO2 with metal oxide to produce stable carbonates. It is also known as Geological sequestration Lentils Protein good choice EAT SMART of fibre & nutrient Your food choices affect the climate which involves injecting CO2 directly into the underground Tomatos Veggies, fruits low in 01234567 fat and colorie high in geological formations (such as nutrient declining oil fields, gas fields saline aquifers and unmineable Beans Broccoli coal have been suggested as Yoghurt Organic, high storage sites). Nuts protein, good fat, Peanut more nutritions butter conventional foods Carbon Sink Rice Potatoes Any system having the capacity to Egg Fish Organic rich accumulate more Chicken omega atmospheric carbon

during a given Solman fish, Pork Processed food. time interval than Cheese releasing CO2. Highest carbon foot print. Example: forest, soil, Beef & Lamb CARBON FOOTPRINT ocean are natural Processed food. car miles driven per 4oz(118.29 ml). consumed Different foods have a different impacts.Here’s how the green sinks. Landfills are house gas emissions (GHGs) of twenty common foods compare. artificial sinks. Figure 8.12: Carbon foot print

203 Environmental Issues

TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 203 01-03-2019 17:00:54 total amount of green house gases produced by acidic soils, increase agricultural productivity, human activities such as agriculture, industries, and provide protection against some foliar deforestation, waste disposal, buring fossil and soil borne diseases. It is a good method fuels directly or indirectly. It can be measured of preventing waste woods and logs getting for an individual, family, organisation like decayed instead we can convert them into industries, state level or national level. It is biochar thus converting them to carbon storage usually estimated and expressed in equivalent material.

tons of CO2 per year. The burning of fossil 8.9 Rain water harvesting – RWH fuels releases CO2and other green house gases. In turn these emissions trap solar energy and (Solution to water crisis – A ecological thus increase the global temperature resulting problem) in ice melting, submerging of low lying areas Rain water canal and inbalance in nature like cyclones, tsunamis and extreme weather conditions. To reduce the carbon foot print we can follow some practices like (i) Eating indigenous fruits and products Drain pipe (ii) Reduce use of your electronic devices (iii) Sand filter Reduce travelling (iv) Do not buy fast and preserved, processed, packed foods. (v) Plant a Water tank garden (vi) Less consumption of meat and sea Over flow pipe to food. Poultry requires little space, nutrients and well less pollution comparing cattle farming. (vii) Rainwater harvesting Well in individual house reduce use of Laptops (when used for 8 hours, it releases nearly 2 kg. of CO annually) (viii) Line 2 Figure 8.13: Pictures of Rain Water dry your clothes. (Example: If you buy imported Harvesting Structures in Ooraniers fruit like kiwi, indirectly it increases CFP. How? The fruit has travelled a long distance in Water storage tank The water is then supplied to shipping or airliner thus emitting tons of CO2) flats, which can be used for domestic purposes Biochar Biochar is another long term method to store carbon. To increase plants ability to store more carbon, plants are partly burnt such as crop Collection tank waste, waste woods to become carbon rich slow A fitted sensor then sends decomposing substances of material called the water to Biochar. It is a kind of charcoal used as a soil the tank amendment. Biochar is a stable solid, rich in carbon and can endure in soil for thousands of years. Like most charcoal, biochar is made Suction tank from biomass via pyrolysis. (Heating biomas in A filter placed in the low oxygen environment) which arrests wood tank clears the Rainwater inlet water of impurities The rainwater that collects on from complete burning. Biochar thus has the the terrace makes its way down a pipe potential to help mitigate climate change via carbon sequestration. Independently, biochar Figure 8.14: Rain Water Harvesting when added to soil can increase soil fertility of Structures in Water Supply sources

204 Environmental Issues

TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 204 01-03-2019 17:00:56 Rainwater harvesting is the accumulation and Important lakes in Tamil Nadu storage of rain water for reuse in-site rather than Lakes are man-made surface water harvesting allowing it to run off. Rainwater can be collected systems. They are useful for irrigation, from rivers, roof tops and the water collected drinking, fishing and recreation purposes. It is directed to a deep pit. The water percolates is the responsibility of the individuals as well and gets stored in the pit. RWH is a sustainable as communities collectively to maintain and water management practice implemented not manage water bodies. Understanding catchment only in urban area but also in agricultural fields, areas help us to halt the degradation of water which is an important economical cost effective bodies and protecting it from getting polluted. method for the future. Sholavaram Lake : It is located in 8.9.1 Environmental benefits of Rain Taluk of Thiruvallur District. It is one of the Water Harvesting: rain fed reservoir from where water is drawn for supply to city. The full capacity of the • Promotes adequacy of underground water lake is 65.5 ft. Built in the British era this lake and water conservation. is responsible for treating the guests to water • Mitigates the effect of drought. sports too. This lake is rich in varied species of • Reduces soil erosion as surface run-off is flora and fauna. reduced. Chembarampakkam Lake: It is located about • Reduces flood hazards. 25 km. from Chennai. This lake is 500 yrs old. • Improves groundwater quality and water This lake is a rain table / decreases salinity. fed water body • No land is wasted for storage purpose and which aids the no population displacement is involved. Chennai City in • Storing water underground is an eco- its water supply. A river named friendly measure and a part of sustainable Figure 8.15: water storage strategy for local communities. Adyar also incepts from this Chembarampakkam Lake 8.9.2 Importance of Lakes lake which acts Water bodies like lakes, ponds not only provide as the primary outflow for this reservoir. This us a number of environmental benefits but lake is spread over an area of 15 square km. they strengthen our economy as well as our Lake: It is located in quality of life like health. Lakes as a storage of Kancheepuram district and it is a man-made rain water provides drinking water, improves creation. An ideal spot for an evening picnic, ground water level and preserve the fresh water the widespread pristine waters of the lake are an bio-diversity and habitat of the area where in exceptionally calming sight. The full capacity of occurs. the reservoir is 23.3ft. Kiliyar is a small river that In terms of services lakes offer sustainable originates from Madhuranthagam reservoir. It solutions to key issues of water management spreads to an area of 2908 acres and was built and climatic influences and benefits like by Uttama Chola and the boundaries (stretched nutrient retention, influencing local rainfall, upto 12960 feet) are strengthened by Britishers removal of pollutants, phosphorous and with a storing capacity of 690 million cu.feet. nitrogen and carbon sequestration. Rain water from Cheyyar, Thiruvannamalai and Vandavasi reaches this lake.

205 Environmental Issues

TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 205 01-03-2019 17:00:56 8.10 Sewage disposal PrimaryPrimary treatment SecondarySecondary treatment DDisinfectantisinfecta Sewage disposal treatment helps to AAerationeration tanktank SSecondaryecondary RawRaw sewage transform raw sewage into an easier cclariferlarifer manageable waste and to retrieve ScreensScreens PPrimaryrimary SSecondaryecondary and reuse treated residual sewage eeffluentffluent eeffluentffluent CComminutoromminutor DischargeDischarge to materials. Greenhouse gases like PPrimaryrimary AAirir compressor AcActivatedtivated surfacesurface clarifier carbon-dioxide, methane, nitrous slsludgeudge water oxide are produced during sewage ((oror tertiatertiaryr RReturneturn ssludgeludge pumppump ttreatmentreatmen treatment which apart from causing GritGrit chamberchamber RRawaw or prprimaryimary sludgesludge iiff needeneeded)d the impact on the atmosphere, it also Grit disposaldisposal

affect the urban ecosystem, aquatic SludgeSludge treatement and disposal ecosystems. By making use of Figure 8.16: Sewage treatment plant process flow diagram advanced disposal treatment plants, polluting. climate change and pollution can be Sewage treatment generally involves three minimised. stages, called primary, secondary and tertiary Sewage is waste matter such as faeces or used treatment. dirty water from homes and factories, which flows away through sewers. Sewage treatment Solid waste management is the process of removing contaminants from Solid waste refers to all non liquid wastes which waste water, primarily from household sewage. causes health problems and unpleasant living Physical, chemical and biological processes environment leading to pollution. Solid waste are used to remove contaminants and produce management is a term that is used to refer to the treated waste water, that is safer for the process of collecting and treating solid wastes. It is environment. Sewage contains large amounts all about how it can be changed and recycled as a of organic matter and microbes. This cannot be valuable resource. discharged into natural water bodies like rivers Methods of solid waste management includes and streams directly. Hence sewage is treated in Landfill, incineration, recovery, recycling, sewage treatment plants (STPs) to make it less composting, and pyrolysis. • Technological 0HWKDQH (OHFWULFLW\ /HDFKDWH /HDFKDWH VWRUDJHDQG JHQHUDWRUEXLOGLQJ VWRUDJHWDQN WUHDWPHQWV\VWHP advancement for processing FRPSUHVVRU EXLOGLQJ treatment and disposal of solid 3UREHVWR GHWHFW waste helps in converting it into PHWKDQH OHDNV renewable energy and organic 0HWKDQHJDV 3LSHFROOHFW H[SORVLYH manure. UHFRYHU\ PHWKDQHJDVXVHGDV IXHOWRJHQHUDWH • Electronic waste HOHFWULFLW\ &RPSDFWHG contains toxic materials and are VROLGZDVWH found to be non-biodegradable which causes threat to human health and the smoke during *URXQGZDWHU /HDFKDWHSLSHV recycling and leaching causes PRQLWRULQJ ZHOO great threat to water bodies. *URXQGZDWHU /HDFKDWH Agricultural landfills method PRQLWRULQJZHOO stands a good method to reduce Figure 8.17: Sanitary landfill these problems.

206 Environmental Issues

TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 206 01-03-2019 17:00:57 Liquid Waste Management and implementation. It aims at ensuring Liquid waste includes point source and non- development proposals which integrate bio- point source discharges such as storm water diversity considerations. They are legally and waste water. Examples of liquid waste compliant and include mechanisms for the include wash water from homes, liquids, used conservation of bio-diversity resources and for cleaning in industries and waste detergents. provide fair and equitable sharing of the benefits arising from the use of bio-diversity. Grey water is the one from municipal waste which contains harmful pathogens. Biomonitoring Water coming from domestic equipments The act of observing and assessing the current other than toilets (bathtub, showers, sinks, and state and ongoing changes in ecosystem, washing machine) is also referred as grey water. biodiversity components, landscape including Municipal wastes can be detoxified biologically natural habitats, populations and species. and then recycled. Domestic waste water can be An agricultural drone is an unmanned aerial recycled and used for gardening. vehicle applied to farming in order to help increased crop production and monitor crop 8.11 Environmental Impact Assessment growth. Agricultural drones let farmers see (EIA) their fields from the sky. This bird’s eye-view Environmental Impact Assessment is an can reveal many issues such as irrigation environmental management tool. It helps to problems, soil variation and pest and fungal regulate and recommend optimal use of natural infestations. It is also used for cost effective safe resources with minimum impact on ecosystem method of spraying pesticides and fertilizers, and biotic communities. It is used to predict the which proves very easy and non-harmful. environmental consequences of future proposed developmental projects (example: river projects, dams, highway projects) taking into account inter-related socio-economic, cultural and human-health impacts. It reduces environmental stress thus helping to shape the projects that Figure 8.18: Agricultural drone may suit local environment by ensuring optimal utilization of natural resources and disposal of Bio-diversity impacts can be assessed by wastes to avoid environmental degradation. • Change in land use and cover The benefits of EIA to society • Fragmentation and isolation • A healthier environment • Extraction • Maintenance of biodiversity • External inputs such as emissions, effluents • Decreased resource usage and chemicals • Reduction in gas emission and environment • Introduction of invasive, alien or genetically damage modified species 8.11.1 Biodiversity Impact Assessment • Impact on endemic and threatened flora and (BIA) fauna. Biodiversity Impact Assessment can be 8.12. Geographic Information System defined as a decision supporting tool to help GIS is a computer system for capturing, storing, biodiversity inclusive of development, planning checking and displaying data related to positions

207 Environmental Issues

TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 207 01-03-2019 17:00:59 on Earth’s surface. Also to manipulate, analyse, • Tracking the patterns of urban area manage and present spacial or geographic data. development and the changes in Farmland GPS is a satellite navigation system used to or forests over several years determine the ground position of an object. It is • Mapping ocean bottom and its resources a constellation of approximately 30 well spaced Applications of Satellites satellites that orbit the earth and make it possible Name of the Year of for the people with ground receivers to pinpoint Application their geographic location. Some applications in Satellites Launch SCATSAT – I Sep. 2016 Weather which GPS is currently being used for around forecasting, the world include Mining, Aviation, Surveying cyclone prediction Agricultural and Marine ecosystem. and tracking Importance of GIS services in India • Environmental impact assessment INSAT 3DR Sep. 2016 Disaster management • Disaster management CARTOSAT – 2 Jan. 2018 Earth observation • Zoning of landslide hazard GSAT – 6A March Communication • Determination of land cover and land use 2018 • Estimation of flood damage CARTOSAT – 2 Jan. 2018 To watch border • Management of natural resources (100th Satellite) surveillance • Soil mapping • Wetland mapping Summary • Irrigation management and identification of Green house effect leads to climate change volcanic hazard which results in global warming. Deforestation • Vegetation studies and mapping of causes soil erosion, whereas Afforestation helps threatened and endemic species. to restore vegetation and increases ground Remote Sensing is the process of detecting water table. Agrochemicals like fertilizers, and monitoring the physical characteristics of pesticides and runoff from fields cause soil an area by measuring its reflected and emitted infertility and in turn depletes the growth of radiation at a distance from the targeted area. plants. Help the government to retrieve the It is an tool used in conservation practices by vegetation. Regeneration of trees by Agroforestry giving exact picture and data on identification of is possible with the involvement of community even a single tree to large area of vegetation and and government. Help to conserve the flora and wild life for classification of land use patterns fauna in their natural habitat and man-made and studies, identification of biodiversity rich or environments like zoological parks and national less areas for futuristic works on conservation parks. IUCN is the oldest environmental and maintenance of various species including organisation which protects endemic and commercial crop, medicinal plants and threatened species. Mitigation of carbon in the atmosphere done in the form of sequestration. threatened plants. Rain water harvesting is done for improving the Specific uses ground water table. Importance and location • Helps predicting favourable climate, for the of lakes in Tamil Nadu which aids water supply study of spreading of disease and controlling to the city is a measure of conservation of it. drinking water. Assessment of Environment • Mapping of forest fire and species and Biodiversity helps to study risk analysis and distribution. disaster management. Forest cover is monitored through Remote sensing and GIS.

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 208 01-03-2019 17:00:59 Evaluation a) N20 and CO2 b) CFCs and N20 1. Which of the following c) CH4 and CO2 d) CH4 and CFCS would most likely help to 6. One of the chief reasons among the following slow down the greenhouse for the depletion in the number of species effect. making endangered is a) Converting tropical a) over hunting and poaching forests into grazing land for cattle. b) green house effect b) Ensuring that all excess paper packaging c) competition and predation is buried to ashes. d) habitat destruction c) Redesigning landfill dumps to allow 7. Deforestation means methane to be collected. a) growing plants and trees in an area where d) Promoting the use of private rather than there is no forest public transport. b) growing plants and trees in an area where 2. With respect to Eichhornia the forest is removed Statement A: It drains off oxygen from water c) growing plants and trees in a pond and is seen growing in standing water. d) removal of plants and trees Statement B: It is an indigenous species of 8. Deforestation does not lead to our country. a) Quick nutrient cycling a) Statement A is correct and Statement B is b) soil erosion wrong. c) alternation of local weather conditions b) Both Statements A and B are correct. d) Destruction of natural habitat weather c) Statement A is correct and Statement B is conditions wrong. d) Both statements A and B are wrong. 9. The unit for measuring ozone thickness a) Joule b) Kilos 3. Find the wrongly matched pair. c) Dobson d) Watt a) Endemism - Species confined to a 10. The lake which was built in British era and is region and not found near the Indian Army Base anywhere else. a) b) Hotspots - Western ghats b) Maduranthagam lake c) Ex-situ c) Sholavaram lake Conservation - Zoological parks d) Chembrambakkam lake d) Sacred groves - Saintri hills of Rajasthan 11. People’s movement for the protection of e) Alien sp. environment in Sirsi of Karnataka is Of India - Water hyacinth a) Chipko movement 4. Depletion of which gas in the atmosphere b) Amirtha Devi Bishwas movement can lead to an increased incidence of skin c) Appiko movement cancer? d) None of the above a) Ammonia b) Methane 12. The invasive species introduced in India c) Nitrous oxide d) Ozone from Philippines 5. One green house gas contributes 14% of total a) Lantana b) Prosopis global warming and another contributes 6%. c) Parthenium d) Kappaphycus These are respectively identified as

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TN_GOVT_BOTANY_XII_PAGES_191 -211 CH 08.indd 209 01-03-2019 17:00:59 13. Cash crops like sesame and pearl millet are Glossary inhibited by the invasive plant Algae Blooms: Sudden sprout of algae growth, a) Kappaphycus b) Parthenium which can affect the water quality adversely and c) Lantana d) Prosopis indicate potentially hazardous changes in local 14. The plants which are grown in silivpasture water chemistry. system are Atmosphere: A major regional community of a) Sesbania and Acacia plants and animals with similar life forms and b) Solenum and Crotalaria environmental conditions. c) Clitoria and Begonia Biodegradable waste: Organic waste, typically d) Teak and sandal coming from a plant or animal sources, which 15. IUCN red list categories has developed other living organisms can break done. criteria for threatened species. The criteria Biosphere: The portion of earth and its ‘C’ refers to atmosphere that can support life. a) Geographic range b) Quantitiative analysis Effluent: Liquid waste such as sewage and c) Small population size and decline liquid waste from industries. d) population reduction Landfill: A site that is specially designed to 16. What is ozone hole? dispose of waste and operates with a license granted by the Environmental Protection 17. Give four examples of plants cultivated in Agency (EPA). commercial agroforestry. Oil spill: The harmful release of oil into the 18. What are agrochemicals? environment, usually through water, which is 19. Expand CCS. very difficult to clean up and often kills, birds, fish and other wildlife. 20. How do forests help in maintaining the climate? Radiation: A form of energy that is transmitted in waves, rays or particles from a natural source 21. How do sacred groves help in the such as the sun and the ground or an artificial conservation of biodiversity? source such as an X-ray machine. 22. Which one gas is most abundant out of Radioactive: A materials is said to be radioactive the four commonest greenhouse gases? if it emits radiation. Discuss the effect of this gas on the growth Recycle:To break waste items done into their of plants? raw materials, which are then used to remake 23. Distinguish between endangered, the original item or to make new items. vulnerable and rare species. Sewage: Liquid waste from communities which 24. Suggest a solution to water crisis and may be a mixture of domestic effluent from explain its advantages. homes, and liquid waste from industries. 25. Explain afforestation with case studies. Sustainable development: Development using hand of energy sources in a way that meets the 26. What are the effects of deforestation and needs of people today without reducing the benefits of agroforesty? ability in future generation to meet their own needs.

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Environmental Issues

Let us know about the Environmental issues using the EARTH NOW app through this activity.

Steps

• Type the URL or scan the QR code to open the activity page. • Click on the satellite it displays the shape and activities of the satellite. • Click on the Vital Signs to see the global Climate data including surface air temperature, Carbondioxide, Ozone, etc.,

Step 1 Step 2 Step 3 Step 4

URL:

https://play.google.com/store/apps/details?id=gov.nasa.jpl.earthnow.activity

* Pictures are indicative only

211 Environmental Issues

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