Tamilnadu State Board New Syllabus Samacheer Kalvi 12th Bio Botany Guide Pdf Chapter 8 Environmental Issues Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 12th Bio Botany Solutions Chapter 8 Environmental Issues

12th Bio Botany Guide Environmental Issues Text Book Back Questions and Answers

I. Choose the correct answer
Question 1.
Which of the following would most likely help to slow down the greenhouse effect.
a) Converting tropical forests in to grazing land for cattle.
b) Ensuring that all excess paper packing is buried to ashes.
c) Redesigning landfill dumps to allow methane to be collected.
a) Promoting the use of private rather than puplic transport.
Answer:
c) Redesigning landfill dumps to allow methane to be collected.

Question 2.
With respect to Eichhornia.
Statement A: It drains off oxygen from water and is seen growing in standing water.
Statement B: It is an indigenous spicies of our country.
a) Statement A is correct and Statement B is wrong.
b) Both Statements A and B are correct.
c) Statement A is correct and Statement B is wrong.
d) Both Statements A and Bare wrong.
Answer:
a) Statement A is correct and Statement B is wrong.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 3.
Find the wrongly matched pair.
a) Endemism – Species confined to a region and not found anywhere else.
b) Hotspots – Western ghats.
c) Ex-situ Conservation – Zoological parks.
d) Sacred groves – Saintri hills of Rajasthan.
e) Alien sp. Of India – Water hyacinth.
Answer:
e) Alien sp. Of India – Water hyacinth.

Question 4.
Depletion of which gas in the atmosphere can lead to an increased incidence of skin cancer?
a) Ammonia
b) Methane
c) Nitrous oxide
d) Ozone
Answer:
d) Ozone.

Question 5.
One green house gas contributes 14% of total global warming and another contributes 6%. These are respectively identified as
a) N2O and CO2
b) CFCS and N2O
c) CH4 and CO2
d)CH4 and CFCS
Answer:
b) CFCS and N2O.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 6.
One of the chief reasons among the following for the depletion in the number of species making endangered is.
a) over hunting and poaching
b) green house effect
c) competition and predation
d) habitat destruction
Answer:
d) habitat destruction.

Question 7.
Deforestation means
a) growing plants and trees in an area where there is no forest
b) growing plants and trees in an area where the forest is removed
c) growing plants and trees in a pond
d) removal of plants and trees
Answer:
d) removal of plants and trees.

Question 8.
Deforestation does not lead to
a) Quick nutrient cycling
b) soil erosion
c) alternation of local weather conditions
d) Destruction of natural habitat weather conditions
Answer:
a) Quick nutrient cycling.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 9.
The unit for measuring ozone thickness
a) Joule
b) Kilos
c) Dobson
d) Watt
Answer:
c) Dobson

Question 10.
People’s movement for the protection of environment in sirsi of Karnataka is
a) Chipko movement
b) Amirtha Devi Bishwas movement
c) Appiko movement
d) None of the above
Answer:
c) Appiko movement.

Question 11.
The plants which are grown in silivpasture system are
a) Sesbania and Acacia
b) Solenum and Crotalaria
c) Clitoria and Begonia
d) Teak and sandal
Answer:
a) Sesbania and Acacia.

Question 12.
What is the ozone hole?
Answer:
The decline in the thickness of the ozone layer over restricted area is called Ozone hole.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 13.
Give four examples of plants cultivated in commercial agroforestry.
Answer:
Commercial Agroforestry includes Casuarina, Eucalyptus, Malai vembu, Teak and Kadambu trees.

Question 14.
Expand CCS.
Answer:
CCS – Carbon capture and storage.

  • Carbon capture and storage is a technology of capturing carbon dioxide and inject it deep into the underground rocks at a depth of 1 km (or) more.
  • It is an approach to mitigate global warming.

Example:

  • It is capturing CO2 released from industries and power plants.
  • Such as declining oil fields, gas fields saline aquifers and unmineable coal have been suggested as storage sites.
  • Various safe sites have been selected for permanent storage.
  • liquid storage in ocean and solid storage by reduction of CO2 with metal oxide to produce stable carbonates.
  • It is also known as Geological sequestration.

Question 15.
How do forests help in maintaining the climate?
Answer:

  • Forest regulate co2 levels in the atmosphere.
  • If greater the forest area more CO2 is removed and the impact of global climate change is decreased.
  • They regulate ecosystem, protect biodiversity, play an integral part in the carbon cycle.
  • In the tropics water evaporates naturally from trees, increasing cloud cover and keeping temperature cooling.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 16.
How do sacred groves help in the conservation of biodiversity?
Answer:
These are the patches or grove of cultivated trees which are community protected and are based on strong religious belief systems which usually have a significant religious connotation for protecting the community. Each grove is an abode of a deity mostly village God Or Goddesses like Aiyanar or Amman.

448 grooves were documented throughout Tamil Nadu, of which 6 groves (Banagudi shola, Thirukurungudi and Udaiyankudikadu, Sittannnavasal, Puthupet and Devadanam) were taken up for detailed floristic and faunistic studies. These groves provide a number of ecosystem services to the neighbourhood like protecting watersheds, fodder, medicinal plants, and microclimate control.

Question 17.
Which one gas is most abundant out of the four commonest greenhouse gases? Discuss the effect of this gas on the growth of plants?
Answer:
CO2 Carbon-di-oxide is the most abundant among greenhouse gases.

  • Low agricultural productivity in tropics.
  • Frequent heat waves (weeds, pests, fungi, need warmer temperature)
  • increase of vectors and epidemics
  • strong storms and intense flood damage.
  • Water crisis and decreased irrigation
  • Change in flowing seasons and pollinators
  • Change in species distributional ranges.
  • Speakes extinction.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 18.
Suggest a solution to water crisis and explain its advantages.
Answer:
Rainwater harvesting is the accumulation and storage of rain water for reuse in-site rather than allowing it to run off. Rainwater can be collected from rivers, roof tops and the water collected is directed to a deep pit. The water percolates and gets stored in the pit. RWH is a sustainable water management practice implemented not only in urban area but also in agricultural fields, which is an important economical cost effective method for the future. Environmental benefits of Rain Water Harvesting:

  1. Promotes adequacy of underground water and water conservation.
  2. Mitigates the effect of drought.
  3. Reduces soil erosion as surface run-off is reduced.
  4. Reduces flood hazards.
  5. Improves groundwater quality and water table / decreases salinity.
  6. No land is wasted for storage purpose and no population displacement is involved.
  7. Storing water underground is an eco-friendly measure and a part of sustainable water storage strategy for local communities.

Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 1

Question 19.
Explain afforestation with case studies.
Answer:
Afforestation:

  • Afforestation is planting of trees where there was no previous tree coverage and the conversion of non-forested lands into forests by planting suitable trees to retrieve the vegetation.
  • Example: Slopes of dams afforested to reduce water run-off, erosion and siltation. It can also provide a range of environmental services including carbon sequestration, water retention.

The Man who Single-Handedly Created a Dense Forest

  • Jadav “Molai” Payeng (born 1963) is an environmental activist has single-handedly planted a forest in the middle of a barren wasteland.
  • This Forest Man of India has transformed the world’s largest river island, Majuli, located on one of India’s major rivers, the Brahmaputra, into a dense forest, home to rhinos, deers, elephants, tigers and birds. And today his forest is larger than Central Park.
  • Former vice-chancellor of Jawahar Lai Nehru University, Sudhir Kumar Sopory named Jadav Payeng as Forest Man of India, in the month of October 2013.
  • He was honoured at the Indian Institute of Forest Management during their annual event ‘Coalescence1.
  • In 2015, he was honoured with Padma Shri, the fourth highest civilian award in India.
  • He received honorary doctorate degree from Assam Agricultural University and Kaziranga University for his contributions.

Tamil Nadu Afforestation project TAP I:

TaP I
objectives:

  • It aimed to uplight the quality and life of villagers, abutting forest areas.
  • It is resolve the degraded forests in Tamil Nadu

Tap II
objectives

  • To restore the ecological equilibrium of the forests, watersheds and adjacent villages of Tamil Nadu.
  • To improve the quality of the life of inhabitants through reforestation. Water conservation and sustained community action.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 20.
What are the effects of deforestation and benefits of agroforestry?
Answer:

Effects of deforestation:

  1. Burning of forest wood release stored carbon, a negative impact just opposite of carbon sequestration.
  2. Trees and plants bind the soil particles. The removal of forest cover increases soil erosion and decreases soil fertility. Deforestation in dry areas leads to the formation of deserts.
  3. The amount of runoff water increases soil erosion and also creates flash flooding, thus reducing moisture and humidity.
  4. The alteration of local precipitation patterns leading to drought conditions in many regions. It triggers adverse climatic conditions and alters water cycle in ecosystem.
  5. It decreases the bio-diversity significantly as their habitats are disturbed and disruption of natural cycles.
  6. Loss of livelihood for forest dwellers and rural people.
  7. Increased global warming and account for one-third of total CO2 emission.
  8. Loss of life support resources, fuel, medicinal herbs and wild edible fruits.

Benefits of agroforestry:

  1. It is an answer to the problem of soil and water conservation and also to stabilise the soil (salinity and water table) reduce landslide and water run-off problem.
  2. Nutrient cycling between species improves and organic matter is maintained.
  3. Trees provide micro climate for crops and maintain CO2 balanced, atmospheric temperature and relative humidity.
  4. Suitable for dry land where rainfall is minimum and hence it is a good system for alternate land use pattern.
  5. Multipurpose tree varieties like Acacia are used for wood pulp, tanning, paper and firewood – industries.
  6. Agro-forestry is recommended for the following purposes. It can be used as Farm Forestry for the extension of forests, mixed forestry, shelter belts and linear strip plantation.

12th Bio Botany Guide Environmental Issues Additional Important Questions and Answers

I. Match
Question 1.
Match the column I with column II and select correct option

Column I Column II
A. Methane 1. Thickness of ozone layer
B. u v radiation 2. Global warming
C. 0.3cm (or) 300DU 3. Tanning burning and skin cancer
D. Nitrogenous fertilizers and aerosols 4. 20 times as effective as CO2

Option:
a) A – 4,B – 3, C – 1, D – 2
b) A – 3, B – 2, C – 1, D – 4.
c) A – 2, B – 1, C – 3, D – 4.
d) A – 1, B – 3, C – 2, D – 4.
Answer:
a) A – 4,B – 3, C – 1, D – 2

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 2.
Match the column I with column II and select correct option

Column I Column II
A. Ozone depletion 1. September 16
B. world ozone Day 2. Chlorofluorocarbon
C. Kyoto protocol 3. 1987
D. Montreal protocol 4. 2007

Option:
a) A – 1,B – 2, C – 3, D – 4
b) A – 2, B – 1, C – 4, D – 3.
c) A – 2, B – 3, C – 4, D – 1
d) A – 3, B – 2, C – 1, D – 2.
Answer:
b) A – 2, B – 1, C – 4, D – 3

Question 3.
Match the column I with column II and select correct option

Column I Column II
A. Pinus 1. Nitrate pollution
B. Petunia 2. Indicator of heavy metal
C. Gladiolus 3. SO2 pollution
D. Black locurst tree 4. Fluoride pollution

Option:
a) A – 3, B – 1, C – 4, D – 2.
b) A – 2, B – 3, C – 4, D – 1.
c) A – 1, B – 2, C – 3, D – 4.
d) A – 3, B – 2, C – 1, D – 4.
Answer:
a) A – 3, B – 1, C – 4, D – 2

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

II. State True or False and choose the correct option

Question 1.
A – Eichhornia crassiper decreases the oxygen content of water bodies.
B – Prosopis juliflora enrich soil nutrient and important local species growth.
C – Petunia and chrysanthemum are referred as nitrate phytoindicators.
D – Robinia pseudoacocia is a indicator of heavy metal contamination.
Option:
Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 2
Answer:
b) A – T, B – F, C – T, D – T

Question 2.
A) Jadav “molai payeng” is an forest man of India.
B) The world largest river island, Majuli located on major rivers the Brahmaputra.
C) In 2015 he was honoured with padma shri award in India.
D) He was a student of forest management student.
Option:
Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 3
Answer:
b) A – T, B – T, C – T, D – F.

III. Choose the incorrect statement

Question 1.
Choose the incorrect statement related to effects of ozone depletion.
a) Juvenile mortality of animal, Increased incidence of mutations.
b) Increases the incidence of cataract, throat and lung irritation, emphysema, skin cancer.
c) Flood/ drought, sea water rise, Imbalance in ecosystem affecting flora and fauna.
d) Diminishing the functioning of immune system is not related to ozone depletion.
Answer:
d) Diminishing the functioning of immune system is not related to ozone depletion.

Question 2.
Choose the incorrect statement related to forestry.
a) The tank foreshore plantations have been a major source of firewood in Tamilnadu.
b) The production of woody plants combined with pasture is referred to silvopasture system.
c) Trees provide micro climate for crops and maintain 02 – CO2 balance.
d) Agro-forestry is an integration of trees, animals, water bodies and humans.
Answer:
d) Agro-forestry is an integration of trees, animals, water bodies and humans

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

IV. Choose the correct statement

Question 1.
Choose the correct statement from the following.
a) Agricultural drones are animals used to do heavy agricultural works.
b) CARTOSAT-2 is used to watch border surveillance.
c) The production of flowering plants combined with pasture is reffered to silvopasture system.
d) GTS is a satellite navigation system used to determine the ground position of an object
Answer:
b) and d)

V. Pick out the odd one out and give Reason

Question 1.
In-situ, Ex-situ, National parks, Biosphere Reserves, Remote seming.
a) Remote seming, while other are related to biodiversity conservation.
b) National parks, while others are man made project.
c) Biosphere reserves, detecting and monitoring the physical characteristic of an area.
d) None of the above.
Answer:
a) Remote seming, while other are related to biodiversity conservation.

Question 2.
Reduces flood hazards, decreases salinity Reduces soil erosion, carbon sink.
a) Reduces soil erision. while others are related to Rainwater harvesting system.
b) Carbon sink, while others are related to benefits of Rain water harvesting.
c) Decreases salinity, while others are related to rain water harvesting.
d) Reduces soil erosion, while others are eco friendly method.
Answer:
b) Carbon sink, while others are related to benefits of Rain water harvesting

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 3.
Lichens, Ficus, Pinus, Rose, Gladiolus.
a) Lichens, while others are SO2 pollution.
b) Gladiolus is the heavy metal indicator, while others are related to SO2 pollution.
c) Gladiolus. while others are indicator for SO2 pollution.
d) Pinus is the nitrate indicator, while others are SO2pollution.
Answer:
c) Gladiolus. while others are indicator for SO2 pollution

VI. Pictorial questions

Question 1.
Relative contribution of green house gas are shown below. Which one of the given option is correct?
Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 4
a) A – others, B – CH4, C – CFC, D – O2
b) A – CH4, B – CO2, C – O2,D – CFC
c) A – CO2, B – CH4, C – CFC, D – O2
d) A – others, B – CH4, C – CFC, D – CO2
Answer:
d) A – others, B – CH4, C – CFC, D – CO2

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 2.
Examine the diagram Which is showing the percentage. Find out the Green house gas related to its percentage.
Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 5

Answer:
a) CO2 CH4 CFC others

VII. Assertion and Reason

Question 1.
Assertion: Sacred groves and sacred lakes are community protected Bio-diversity conservation.
Reason: Which are based on strong religious belief system,
a) A is correct R is wrong.
b) A is correct but R does not explains A.
c) A is correct and R is the correct explanation for A
d) A and R are wrong.
Answer:
c) A is correct and R is the correct explanation for A.

Question 2.
Assertion : Appiko movement started in Gubbi Gadde village sirsi in karnataka by panduranga Hegde.
Reason: It is started to protest against felling of trees, monoculture, forest policy and deforestation
a) Both are wrong.
b) A and R is correct
c) A is correct R- does not explains A.
d) A is wrong R is correct.
Answer:
b) A and R is correct

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

VIII. Spot the error

Question 1.
Biosphere Reserves, National parks and wildlife sanctuaries are community protected Bio-diversity conservation.
Answer:
Biosphere Reserves,National parks and wild life sanctuaries are Goverment protected Bio-diversity conservation.

IX. Choose the incorrect pair

Question 1.
Choose the incorrect pair.
A) Protein Bank-Fodder production.
B) Livefence, foddertree – Erythrina spp.
C) Agro forestry – Extension of forest, mixed forestry.
D) Social forestry-Jadav,Molaipayeng.
Answer:
D) Social forestry-Jadav,Molai payerg

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

X. Read the following statement with two blanks A and B select the correct option for blank A and B.

Question 1.
Eichhornia crassipes is an invasive weed native to south America. It affects the growth of A and finally leads to B.

A B
a) Phytoplankton 1) eutrophication
b) Prosopis 2) oxygen content
c) Topography 3) geology
d) Plants 4) environmental issues

Answer:
a) Phytoplankton – 1) eutrophication

XI. Fill in the blanks Answers

1. ………………. is another long term method to store carbon.
Answer:
Biochar

2. …………………. is the total amount of green house gases produced by human activated.
Answer:
Carbon foot print

3. Eating indigenous fruits and products are reduce ………………
Answer:
Carbon foot print

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

4. The forest, soil, ocean are …………………. and landfills are ………….. sinks.
Answer:
Natural, artificia
Dobson unit

5. The thickness of the ozone column of air is measured in terms of ………………
Answer:
Chloro fluro carban

6. …………………. is the anthropogenic greenhouse gas.
Answer:
Tank Foreshore

7. _____ plantations have been a major source of fire wood in Tamilnadu.
Answer:
Plantations

8. World ozone Day is celebrated on ……………….
September 16

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

XII Choose the correct option

Question 1.
Which creates a breeding habitat for disease causing mosquito Anopheles?
a) Eichhornia crassipes
b) Lantana camara
c) Prosopis juliflora
d) Parthenium hysterophorus
Answer:
a) Eichhornia crassipes

Question 2.
Which one the activities is replacement of conventional electrification project solar panels or other energy efficient boilers?
a) Clean Development Mechanism (CDM)
b) Chloro Fluoro Carbon (CFC)
c) Certified Emission Reduction (CER)
d) TamilNadu Afforestation Project (TAP)
Answer:
a) Clean Development Mechanism (CDM)

Question 3.
Some of the major species cultivated in Agroforestry for commercial use:
a) Erythrina, Albizzia
b) Malaivembu, Kadambu
c) Acacia, Azadirachta Indica
d) Sesbania, Acacia
Answer:
b) Malaivembu, Kadambu

Question 4.
Which one of the following is not a carbon sequestration method?
a) Forest conservation and soil conservation
b) Carbon foot print
c) Biochar
d) Increasing the number of animals.
Answer:
d) Increasing the number of animals.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 5.
Chlorella, sceuedesmus, chroococcus and chlamydomonas are used globally for
a) conservation movement
b) micro climate.
c) carbon sequestration
d) Biochar preparation.
Answer:
c) Carbon sequestration

Question 6.
Botanical garden, zoological park, in-vitro conservation, cryo preservation, seedling, tissue culture and DNA banks are ………………..
a) Sacred groves
b) In-situ conservation.
c) Ex-situ conservation
d) Appiko movement
Ans:
c) Ex-situ conservation

Question 7.
…………….. grooves were documented through out Tamil Nadu
a) 446
b) 447
c) 448
d) 449
Answer:
c) 448

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 8.
Species which is present in some part of continent or present in single island is.
a) Endemic
b) Epidemic
c) Pandamic
d) Sporadic
Answer:
a) Endemic

Question 9.
Approximately one third of India flora have been identified in Indian Himalayas, Peniris India, and Andaman nicobar island it is ……………… species.
a) pandamic
b) epidemic
c) endemic
d) sporadic
Answer:
c) endemic.

Question 10.
Bentinckia condappana tree, which is endemic to………………… of Tamil Nadu and kerala
a) Western ghats
b) Peninsular
c) Coastal
d) Slope
Answer:
a) Western ghats.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 11.
Lianas, Nepenthes khasiyana is endemic to …………….. of meghalaya
a) Western ghat
b) Peninsular
c) Meghalaya
d) Khasi hills
Answer:
d) Khasi hills

Question 12.
Macroalgae and Maine grasses and Mangloves have ability to mitigate ………………..
a) N2O
b) CFC
c) CO2
d) CH4
Answer:
c) CO2

Question 13.
Trees like Eugenia Caryo phyllata, Tecomastans cinnamomum verum have high capacity to sequester …………….
a) N2O
b) Carbon
c) Methane
d) CFC
Answer:
b) Carbon

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 14.
Which one of the following is an alien invasive species?
a) Mangifera indica
b)Eichhornia crassipes
c) Solanum nigrum
d) Zizipus jujupa
Answer:
b) Eichhornia crassipes

Question 15.
Environmental management tool is an …………………
a) Biodiversity Impact assessment
b) Environmental Impact assessment
c) Bio monitoring
d) G I S
Answer:
b) Environmental Impact assessment

Question 16.
……………. system is used in mining, Aviation, surveying agricultural and marie ecosystem.
a) GIS
b) GPS
c) BIA
d) EIA
Answer:
b) GPS

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 17.
InSAT3DR Satellites used in …………………….
a) Earth observation
b) Communication
c) Disaster management
d) Weather forecasting
Answer:
c) Disaster management

Question 18.
Now a days, scientists suggest carbon sequestration is a solution for global warming. The reason is
a) The balance between photosynthesis and respiration is disturbed
b) The absorption process of plants from the soil is disturbed
c) Due to high intensity of light respiration process is disturbed
d) Carbon sequestration is not the solution for global warming.
Answer:
d) Carbon sequestration is not the solution for global warming.

Question 19.
Reforestation refers to
a) Chipko movement
b) Development of forest in an area which was already subjects to deforestation
c) Development of forest through cultivabel land
d) None of there
Answer:
b) Development of forest in an area which was already subjects to deforestation.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 20.
World’s must problematic aquatic weed is
a) Clitoria
b) Parthenium
c) Eichhornia crassipes
d) sesbania
Answer:
c) Eichhornia crassipes.

Question 21.
Which of the following gas related to release cars with catalytic converter and buring of organic matter.
a) CO2
b) Methane
c) N2O
d) CFC
Answer:
c) N2O

Question 22.
The Ozone layer of troposphere is called
a) Middle Ozone
b) Ozone Shield
c) Bad Ozone
d) Good Ozone
Answer:
c) Bad Ozone

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 23.
Which one of the following is a livefence of fodder?
a) Gliricidia sepium
b) Nerium
c) Aloevera
d) Chrysanthemum
Answer:
a) Gliricidia sepium

Question 24.
Coral bleeching observed in Gulf of mannar, Tamil Nadu due to ………………..
a) Decreases of fresh water
b) Low rainfall
c) Green house
d) Dust particles
Answer:
c) green house

Question 25.
Read the following statement and fill it with correct answer in the blank A and B the ozone layer of the troposphere is called A and the ozone layer of startosphere is known as B ……………..
a) important, useful
b) bad and lower
C) bad zone, good zone
d) good zone,bad zone
Answer:
c) bad zone, good zone

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 26.
The purple and blue colours of ozone picture indicate ……………. ozone.
a) Least
b) High
c) Medium
d) Large
Answer:
a) Least

Question 27.
The yellow and red colours of ozone picture indicate ……………….. ozone.
a) more
b) medium
c) low
d) least
Answer:
a) more

Question 28.
The objective of clean development mechanism are/is
a) Prevention of dangerous climate change
b) Reduction of emission of green house gases
c) Both (a) and (b)
d) Reduction of electricity generation and its need.
Answer:
c) Both (a) and (b)

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 29.
Remote sensing is .
a) Mapping ocean bottom and its resources
b) Mapping forest fire
c) Mapping species distribution
d) all the above
Answer:
d) all the above

Question 30.
Bentinckia and Baccaurea are …………….. plants.
a) Invasive species
b) Endemic
c) Silvopasture
d) None of these
Answer:
b) Endemic

Question 31.
Eichornia. prosopis are plants ………………….
a) endemic
b) Invasive
c) Silvopasture
d) None of these
Answer:
b) Invasive

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 32.
The management of forest and afforestation on barren lands is …………………..
a) agroforestry
b) Silvopasture
c) Social forestry
d) Afforestation
Answer:
c) Social forestry

Question 33.
Which is fast growing and more adopted species?
a) Invasive species
b) epidemic species
c) Pandamic species
d) Wild species
Answer:
a) Invasive species

Question 34.
The plant species (or) community acts as a measure of enviornmental conditions is referred as …………….
a) Both b and d
b) Plant indicators
c) Protocol
d) Biological indicators
Answer:
b) Plant indicators

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 35.
The international treaty called …………….. (1987) was held in Canada on substances that deplete ozone layer.
a) Montreal Protocol
b) Kyoto protocol
c) CDM
d) CER
Answer:
a) Montreal Protocol

XIII. Two Marks

Question 1.
Why the green house gases cause global warming
Answer:

  • Green House effect is a process by which radiant heat from the sun is captured by gas in the atmosphere that increase the temperature of the earth.
  • The gases that capture the heat are called Green Hosue gases includes CO2, CH4, N2O and CFC.

Question 2.
Draw the pie diagram which shows Relaitive contribution of green house gases.
Answer:

  • Green House effect is a process by which radiant heat from the sun is captured by gas in the atmosphere that increase the temperature of the earth.
  • The gases that capture the heat are called Green House gases includes CO2, CH44, N2Oand CFC
    Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues 6

Question 3.
Why dust and humid night than dust free nights? (or) Does clouds and dust particles cause global warming?
Answer:

  • Yes, clouds and dust particles can also produce Green House effect.
  • That is why clouds dust and humid nights are warmer than clear dust free dry nights.

Global warming

  • The increase in mean global temperature due to increased concentration of green house gases is called global warming.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 4.
Differentiate bad ozone from good ozone.
Answer:

Bad ozone good ozone
The ozone layer of the troposphere is called bad zone. This layer does not involve in the absorption of U.V radiation from the sun. The ozone laye of stratosphere is known as good zone because this layer act as a shield for absorbing the UV radiation coming from the sun.

Question 5.
Which is indicating the least ozone part and more ozone part of the atmosphere?
Answer:

  • The colour view of total ozone indicating the least ozone part and more ozone part.
  • The purple and blue colours are where there is the least ozone.
  • The yellows and reads are where there is more ozone.

Question 6.
What would be the result of ozone depletion on living organisms?
Answer:

  • UVB radiation destroys biomolecules (skin aging) and damaging living tissues.
  • UV radiation causing DNA damage, enhancing skin cancer.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 7.
Is there any hole in the ozone?
Answer:

  • No. If the ozone chield is damaged by the chlorofluoro carbon widely used in refrigeration, aerosol, chemicals used as cleaners in industries.
  • The decline in the thickness of the ozone layer over restricted area is called ozone hole.

Question 8.
What are the main objectives of Montreal protocol?
Answer:
The main goal of it is gradually eliminating the production and consumption of ozone depleting substances and to limit their damage on the earth’s ozone layer.

Question 9.
What is Agroforestry?
Answer:

  • Agroforestry is an integration of trees crops and livestock on the same plot of land.
  • The main objective is on the interaction among them.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 10.
What is silvopasture? (or) What is of degraded forests recreation forestry?
Answer:

  • The production of wood plants combined with pasture is referred to silvopasture system.
  • The trees and shrubs may be used primarily to produce fodder for livestock (or) grown for timber, fuel wood and fruit (or) to improve the soil.

Question 11.
Differentiate Agroforestry and Social forestry.
Answer:

Agro forestry Social forestry
Agro forestry is an integration of trees crops and livestock on the same plot of land It is a sustainable management of forest by local communities.
The main objective is on the interaction among them The main objective is carbon sequestration depollution, deforestation forest restoration and providing indirect employment.

Question 12.
What could be the causes for deforestation?
Answer:

  • The conversion of forest into agricultural plantation and livestock ranching is a major cause of deforestation.
  • Developmental activities like road construction electric tower lines and dams.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 13.
Who is called as Forest Man of India? Why?
Answer:

  • Former vice Chancellor of Jawaharlal Nehru University Sudhir Kumar named Jadav payeng as Forest Man of India.
  • He has transformed the world’s largest river island Majuli (located on river of Brahmaputra) into dense forest, home to rhinos, deers, elephants, tigers and birds.

Question 14.
What is invasive species?
Answer:
A non – native species to the ecosystem (or) country that spreads naturally, interferes with native species, poses a serious threat to the ecosystem and cause economic loss.

Question 15.
Conservation movement – What does it signifies.
Answer:
A community level participation can help in preservation and conservation of our environment.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 16.
What is Five F’s? Which is related to what?
Answer:

  • > Main aim of chipko movement was to give a slogan of Five – Fs. food, fodder, fuel, fibre and fertilizer.
  • > It make the communities self sufficiency in their basic needs.

Question 17.
Each grove is an abode of a diety mostule Village God (or) Goddesses, like Aiyanar (or) Amman – What does it states?
Answer:

  • There are called scared groves.
  • The patches (or) grove of cultivated trees which are community protected and based on religeous belief system.
  • There are 448 groves were documented through out Tamilnadu.

Question 18.
What is Biochar?
Answer:

  • It is another Long term method to store carbon.
  • Plants are partly burnt such as crop waste woods to become carbon rich slow decomposing substances called Biochar.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 19.
What is carbon foot print?
Answer:
C.F.P is the total amount of green house gases produced by human activities such as agriculture,Industries, deforestation, waste disposal burning fossil fuel directly (or) indrectly.

Question 20.
What are the benefits related to environmental impact assessment?
Answer:

  • Benefit are healthier environment.
  • Maintenance of bio diversity
  • Decreased resource usage.
  • Reduction in gas emission and environment damage.

Question 21.
What is Biomonitoring?
Answer:
The act of observing and assessing the current state ongoing
a) changes in ecosystem
b) bio diversity components
c) landscape including natural habitat
d) population and species.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 22.
What is Agricultural drone?
Answer:

  • Agricultural drone is an unmanned aerial vehicle to help increased crop production and monitor crop, growth.
  • Farmers can see their fields from the sky.

Question 23.
What are the uses of agricultural drone (or) Bio monitoring?
Answer:

  • This bird’s – eye – view instrument can reveal many issues such as irrigation problems, soil variation pest and fungal infestations
  • It is also used for cost effective safe method of spraying pesticides and fertilizers.

Question 24.
What Geographic Information system?
Answer:

  • GIS is a computer system for capturing storing, checking, and displaying data related to positions on earths surface.
  • Also manipulate, analyse, manage and present special (or) geographic data.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 25.
What are the scope of GPS satellite? (or) (Global Positioning System)
Answer:

  • Global positioning system is satellite navigation system used to determine the ground position of an object.
  • A constellation of approximately 30 well spaced Satellites that orbit the earth and make it possible geographic location.
    eg:- Mining, surveying Agricultural and marine ecosystem.

Question 26.
Which is providing exact picture and data on identification of even a single tree to large area and wild lifor for classification?
Answer:
Remote sensing is the process of datelining and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance from the target area.

Question 27.
What are green house gases?
Answer:

  • The gases that capture heat are called Green house gases.
  • Which includes CO2 , CH4 , Nitrous oxide (N2O) chioro fluoro carbon.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 28.
If you buy imported fruit like Kilvi indirectly it increases (GFP) carbon foot print. How?
Answer:
The fruit has travelled a long distance in shipping (or) airlines thus emitting tons of cO2.

Question 29.
Which is names of Alien invasive species?
Answer:

  • Eichhornia crassipes
  • Prosopisjuliflora
  • parthenium hysterophorus

Question 30.
Define carbon sink. Give an example
Answer:
Any system having the capacity to accumulate more atmospheric carbon during a given time interval than releasing CO2
Example :- forest, soil, clean are natural sinks, Landfills are artificial sinks.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

XIV. Three Marks

Question 1.
What are the effects of Green House Gases? Give example.
Answer:

  • Increase in green house gases leads to irreversible changes in ecosystem and climatic patterns.
  • eg:- Coral bleaching observed in Gulf of mannen Tamilnadu. [coral system is affected by increase in temperature]

Question 2.
Why we want to control global warming? Write the (or) effects of global warming.
Answer:

  • Rise in global temperature which causes sea levels to rise as polar ice caps and glaciers begin to melt causing submergence of many coastal cities in many parts of the world.
  • There will be drastic change in whether patterns bringing more floods (or) droughts in some areas
  • Biological diversity may get modified.

Question 3.
What are the reasons for global warming?
Answer:

  • Drastic increase in population resulted in demand for more productivity of food, fibres fuels.
  • Which led to many environmental issues in agriculture, land use modification resulting in loss of biodiversity, land degradation reducing in fresh water availability resulting man mode global warming.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 4.
Global warming is a threatening problem nowadays. What are the stratifies to deal with it?
Answer:

  • Increasing the vegetation cover, grow more trees.
  • Reducing the use of fossil fuels and green house gases.
  • Minimising use of nitrogenous fertilizers and aerosols.

Question 5.
Why ozone layer is known as ozone shield?
Answer:
Ozone layer is a region of earth’s stratosphere that absorbs most of the sun’s ultra violet radiation. So it is called as ozone shield.

Question 6.
What is Dobson unit?
Answer:

  • DU is the unit of measurement for total ozone.
  • One DU (0.001 atm.cm) is the number of molecules of ozone that would be required to create a layer of pure ozone 0.01 mm thick at a temperature of 0°C and a pressure of atmosphere.
  • Total ozone layer over the earth surface is 0.3 centimetres (3mm) thick and is writtern can we ozone

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 7.
Can we see ozone layer?
Answer:

  • It is not very strong layer but it will contribute blue colour to the sky even at the very low concentration.
  • We can visualize by using satellites.

Question 8.
Why was Montreal protocol signed?
Answer:

  • During 1970’s research findings indicated that man – made chlorofluoro carbons reduce and convert ozone molecules in the atmosphere.
  • Vienna conference provided the frame works necessary to create regulative measures in the form of Montreal protocol to climate production and consumption of ozone depleting substances.

Question 9.
What is Montreal protocol? What is its aim?
Answer:

  • The international treaty called the Montreal protocol (1987) was held in Canada on substances that deplete ozone layer.
  • The main goal of it is gradually eliminating the production and consumption of ozone depleting substances and to limit their damage on the earth ozone layer.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 10.
What is clean development mechanism (or) Kyoto protocol?
Answer:

  • CDP (or) protocol (2007) provides project based mechanisms with two objectives.
  • To prevent dangerous climate change and to reduce green house gas emissions.
  • It help the countries to reduce (or) limit emission and stimulate sustainable development.
    eg:- Replacement of conventional electrification projects with solar panels (or) other energy efficient boilers.

Question 11.
Differentiate protein Bank from live fence of fodder trees and hedges.
Answer:

Protein Bank Live fence of fodder trees and hedges
Various multipurpose trees are planted in and around farm lands and range lands mainly for fodder production. Various fodder trees and hedges are planted as live fence to protect the property from stray animals.
eg: Acacia nilotica, Azadirachta indica, Albizzia lebbek. eg: Gliricidia sepiutn Sesbania grandi flora Acacia spp.

Question 12.
What is social forestry?
Answer:

  • It refers to the sustainable management of forests by local communities.
  • de-pollution, deforestation, forest restoration and providing indirect employment.
  • Its refers to the management of forests and afforestation of barren lands.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 13.
Why forestry extension centres are important? (or) What ae the major activities of forestry extension centre?
Answer:

  • Training on tree growing methods.
  • Publicity and information regarding tree growing
  • Raising and supply of seedlings on subsidy.
  • Awareness creation among school children and youth about the importance of forests through training camps.

Question 14.
Forest, soil, ocean are called natural sink why? (or) What is carbon sink?
Answer:
Any system having the capacity to accumulate more atmospheric carbon during a given time interval than releasing CO2.
eg: Landfills are artificial sinks forest, soil, ocean are natural sinks.

Question 15.
Why Eichhorinia crassipes is called Terror of Bengal?
Answer:

  • Its widespread growth affects the growth of phytoplanktons and finally changing the aquatic ecosystem.
  • It also decreases the oxygen content of the water bodies which leads to eutrophication.
  • It poses a threat to human health because it creates a breeding habitat for disease causing mosquitoes and snails.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 16.
Differentiate Chipko movement and Appiko movement.
Answer:

Chipko movement Appiko movement
People protested by hugging trees together which were felled by a sports good company. This movement started to protest against felling of trees , monoculture forest policy and deforestation.
It was started by the tribal women of Himalayas Later transformed into chipko movement by Sunderlal Bahuguna. It was started in Gubbi Gadde Village near Sirsin in Karnataka by Pandurang Hedge.

Question 17.
Differentiate in – Situ conservation and ex-site conservation.
Answer:

In – Situ conservation Ex – Situ conservation
Conservation and management of genetic resources in their natural habitat. It is a method of conservation. Where species are protected outside their natural environment.
It includes animal species forest trees medicinal and aromatic plants under threat are conserved by this method.
eg: National parks and Bisphere Reserve
It includes botanical garden, Zoological park gene, pollen, seed, seeking, tissue culture and DNA banks.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 18.
What is Geological sequent ration?
Answer:
Various safe sites have been selected for permanent storage, liquid storage in the ocean and solid storage by reduction of CO2 called Geological sequestration.

Question 19.
Write the benefits of environmental impact assessment.
Answer:

  • A healthier environment.
  • Maintenance of biodiversity
  • Decrased resource usage.
  • Reduction in gas emission and environment damage.

Question 20.
What is environmental impact assessment?
Answer:

  • It is an environmental management tool.
  • It helps to regulate and recommend optimal use of natural resources with minimum impact on ecosystem and biotic communication.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 21.
What is Bio – diversity impact Assessment?
Answer:
It can be defined as a decision supporting tool to help biodiversity development planning and implementation.

Question 22.
How Bio – diversity impacts can be assessed?
Answer:

  • Change in land use and cover
  • Fragmentation and isolation
  • External inputs such as emissions, effluents and chemicals impact on endemic and threatened flora and faura.

Question 23.
Write a short note on production of methane?
Answer:
Methane is 20 times as effective as CO 2 at trapping heat in the atmosphere.
It sources are attributed paddy cultivation, cattle rearing, bacteria in water bodies, fossil fuel production. Ocean, non – wetland soils and forest/wild fires.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 24.
Write a note on (N2O) Nitrous Oxide?
Answer:

  • It is naturally produced in oceans from biological sources of soil and water due to microbial actions and rainforests.
  • Man-made sources include nylon and nitric acid production, use of fertilizers in agriculture manures cars with catalytic converter and burning of organic matter.

Question 25.
Write the significances of lakes.
Answer:

  • Water bodies like lakes, ponds not only provide us a number of environmental benefits but they strengthen our economy as well as our quality of life like health.
  • Lakes as a storage of rain water provides drinking water, improves ground water level and preserve the fresh water bio-diversity and habitat of the area where in occurs
  • In terms of services lakes offer sustainable solutions to key issues of water management and climatic influences and benefits like nutrient retention, influencing local rainfall removal of pollutants, phosphorous and nitrogen and carbon sequestration.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

XV. Five Marks

Question 1.
Define Global warming. Write the reasons for it what are green hours Gases? What are the human activities lead to produce green house effect?
Answer:
Global Warming

  • The increase in mean global temperature due to increased concentration of green house gases is called global warming.

Reasons for global warming

  • Drastic increase in population resulted in demand for more productivity of foof, fibres fuels.
  • Which led to many environmental issues in agriculture, land use modification resulting in loss of biodiversily, land degradation reduction in fresh water availanility resulting man made global warming.

green house gases

  • The gases that capture heat are called Green house Gases.
  • Which includes CO2, CH4, Nitrous oxide (N2O) and chlorofluoro carbon.

Human activities lead to produce the green house effect.
– Human activities lead to produce the green house effect by

  • Buring fossil, which release CO2 and CH4
  • Way of Agriculture and animal husbandry practice.
  • Electrical gadgets like refrigerator and air conditioners release chloro fluoro carbons.
  • The fertilizers used in Agriculture which release N2O
  • The emissions from automoblies.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 2.
Write about Natural and anthropogenic sources of Green House Gases Emission.
Answer:
CO2 (Carbon dioxide)

  • Coal based power plants, by the burning of fossil fuels for electricity generation.
  • Combustion of fuels in the engines of automoniles, commercial vehicles and air plances contribute the most of global warming.
  • Agricultural practices like stubble burning result in emission of CO2
  • Natural from organic matter, volcanoes, warm oceans and sediments.

Methane

  • Methane is 20 times as effective as CO2 at trapping heat in the atomosphere.
  • Its sources are paddv cultivations field cattle rearing, bacteria in water bodies , fossil fuel production, ocean, non-wetland soils and forest/ wild fires.

N2O (Nitrous oxide)

  • It is naturally produced in Oceans from biological sources of soil and water due to microbial actions and rainforest.
  • Man-made sources include nylon and nitric acid production, use of fertilizers in agriculture, manures, cars with catalytic com orter and burning of organic matter.

Question 3.
What are the effects of Global warming on plants? (or) What are the changes may occur on plants and climate due to global warming?
Answer:
Global Warming Effects on Plants

  • Low agriclutural productivity in tropics.
  • Frequent heat waves (Weeds, pests, fungineed warmer temperature).
  • Increase of vectors and epidemics.
  • Strong storms and intense flood damage
  • Water crisis and decreased irrigation.
  • Change in flowering seasons and pollinators.
  • Change in Species distributional ranges.
  • Species extinction.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 4.
The presence (or) absence of certain plants indicates the state of environment by its response. What does it called ? Give some examples.
Answer:
Plant indicators

  • The presence (or) absence of certain plants indicate the state environment by their response.
  • The plant species or plant community acts as a measure of environmental conditions, it is referred as biological indicatores or phytoindicators or plant indicators.

Examples

Plants Indicator for
1. Lichens, Ficus, Pinus, Rose SO2 pollution
2. Petunia, Chrysanthemum Nitrate
3. Gladiolus Flouride pollution
4. Robinia pseudoacacia (Black locust tree) Indicator of heavv metal contamination.

Question 5.
If the ozone layer is affected, U-V radiations on the sun will reach the earth surface and sure many damage.
Can you list out some effects of ozone depletion?
Answer:
Effects of Ozone depletion.
The main ozone depletion are:

  • Increases the incidence of cataract, throat and lung irritation and aggravation of asthma or emphysema, skin cancer and diminishing the functioning of immune system in human beings.
  • Juvenile mortality of animals.
  • Increased incidence of mutations.
  • In plants, photosynthetic chemicals will be affected and therefore photosynthesis will be inhibited. Decreased photosyntheses is will result in increased atmospheric CO2 resulting in global warming and also shortage of food leading to food crisis.
  • Increase in temperature changes the climate and rainfall pattern which may result in flood/drought, sea water rise, imbalance in ecosystems affecting flora and fauna.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 6.
Write an essay on ozone.
Answer:
Ozone shield

  • Ozone layer is a region of earth’s stratosphere that absorbs most of the sun’s ultra violet radiation. So it is called as ozone shield.

Ozone HOLE

  • No. If the ozone shield is damaged by the cholrofluorocarbons widely used in refrigeration, aerosol, chemicals used as cleanes in industries.
  • The decline in the thickness of the ozone layer over restricted area is called ozone hole.

Montreal protocol

  • During 1970s research findings indicated that man-made chlorofluoro carbons reduce and convert ozone molecules in the atmosphere.
  • Vienna conference provided the frame works necessary to create regulative measures in the form of montreal protocol to elimate production and consumption of ozone depleting substances.
  • The international treaty called the montreal protocol (1987) was held in Canada on substances that deplete ozone layer.
  • The main goal of it is gradually eliminating the production and consumption of ozone depleting substances and to limit their damage on the earths ozone layer.

Kyoto protocol

  • C D M (or) protocol (2007) provides project based mechanisms with two objectives.
  • To prevent dangerous climate change and to reduce green house gas emissions.
  • It help the contries to reduce (or) limit emission and stimulate sustainable development
  • eg: Replacement of conventional electrification projects with solar panels (or) other energy efficient boilers.

Question 7.
Write the objectives and achievements of Afforestation.
Answer:
Afforestation Objectives

  • To increase forest cover, planting more trees, increases
  • O2
  • production and air quality.
  • Rehabilitation of degraded forests to increase carbon fixation and reducing CO2 from atmosphere.
  • Raising bamboo plantations.
  • Mixed plantations of minor forest produce and medicinal plants.
  • Regeneration of indigenous herbs/ shrubs. Awareness creation, monitoring and evaluation.

Achievements

  • Degraded forests were restored.
  • Community assets like overhead tanks bore- wells, hand pumps, community halls, libraries, etc were established.
  • Environmental and ecological stability was maintained.
  • Conserved bio-diversity, wildlife and genetic resources.
  • Involvement of community especially women in forest management.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 8.
What is Bio-Diversity conservation movement.
Answer:
Conservation movement

  • A community level participation can help in preservation and conservation of our environement.
  • Our environment is a common treasure for all the living organisms on earth. Every individual should be aware of this and participate actively in the programs meant for the conservation of the local environment.
  • Indian histroy has witnessed many people movements for the protection of environment.

Chipko Movement

  • The tribal women of Himalayas protested against the exploitation of forests in 1972. Later on it transformed into Chipkon Movement by Sundarlal Bahuguna in , Mandle village of Chamoli district in 1974.
  • People protested by hugging trees together which were felled by a sports goods company.

Features of chipko Movement

  • This movement remained non political
  • It was a voluntary movement based on Gandhian thought.
  • It was concerned with the ecological balance of nature.
  • Main aim of Chipko movement was to give a slogan of five F’s _ Food, Fodder, Fuel, Fibre and Fertilizer, to make the communities self sufficient in all their basic needs.

Appiko Movement

  • The famous Chipko Andolen in the Himalayas inspired the villagers of Uttar Karnataka to launch a similar movement to save their forests.
  • This, movement started in Gubbi Gadde a small village near Sirsi in Karnataka by Panduranga Hegde.
  • This movement started to protest against felling of trees, monoculture, forest policy and deforestation.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 9.
Write about endemic centre’s and endemic plants.
Answer:

  • Endemic Centres and Endemic Plants.
  • Endemic species ar plants and animals that exist only in one geographic region.
  • It may be due to various reasons such as isolation, interspecific interactions, seeds dispersal problems.
  • There are 3 Megacentres of endmism and 27 microendemic centres in India.
  • That is ¡nid an Himalayas,Peninsular India and Andaman nicobar islands.
  • A large percentage of Endemic Poaceae. Apiaceae, Asteraceae and Orchidaceae.
Endemic plants Habit Name of endemic centre
Baccaurea Courtallensis Tree Southern Western Ghats.
Agasthiyamalaia Pauciflora Tree Peninsular India.
Bentinckia Condappana Tree Western ghats of Tamil Nadu and Kerala

Question 10.
Write about two approach to mitigate global warming.
Answer:
Carbon Capture and Storage (CCS)

  • Carbon capture and storage is a téchnology of capturing carbondioxide and injects it deep into
    the underground rocks into a depth of 1 km
  • Various safe sites have been selected for permanent storage i.n various deep geological
    formations, liquid storage in the Ocean and solid storage by reduction of CO 2 with metal oxide to
    produce stable carbonates. It is also known as Geological sequestration.

Carbon Sequestration

  • Carbon sequestration is the process of capturing and storing CO 2 which reduces the amount of
    CO 2 in the atmosphere with a goal of reducing global climate change.
  • Carbon sequestration occurs naturally by plants and in ocean.
  • Terrestrial sequestration is typically accomplished through forest and soil conservation practices that enhance the storage carbon.
  • As an example microalgae such as species of Chiorella, Scenedesmus, Chroococcus and Chiamydomonas are used globally for CO 2sequestration.
  • Macroalgae and marine grasses and mangroves are also have ability to mitigate carbon – di – oxide.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 11.
What is Carbon foot print ? How will you reduce this CFP?
Answer:
Carbon Foot Print (CPF)

  • Every human activity leaves a mark just like our footprint. This Carbon foot print is the total amount of green house gases produced by human activities such as agriculture, industries, deforestation, waste disposal, buring fossil etc.

To Reduce carbon foot print

  • Eating indigenous fruits and products.
  • Reduce useofyour electronic devices.
  • Reduce travelling
  • Do not buy fast and preserved, processed, packed foods.
  • Plant a garden
  • Less consumption of meat and sea food. Poultry requires little space, nutrients and less pollution comparing cattle farming.
  • reduce use of Laptops (when used for 8 hours, it releases nearly 2 kg, of CO2 annually).
  • Line dry your clothes.

Question 12.
Write an essay on Environmental impact Assesment and its benefits.
Answer:
Environmental Impact Assessment (EIA)

  • Environment Impact Assessment is an environment management tool.
  • It helps to regulate and recommend optimal use of natural resources with minimum impact on ecosystem and biotic communities.
  • It is used to predict the environmental consequences of future, (example : river, projects, dams, highway projects.)
  • It reduces environmental stress thus helping utilization of natural resources and disposal of wastes to avoid environemental degradation.

The benefits of EIA to society

  • A healthier environment
  • Maintenance of biodiversity
  • Decreased resource usage
  • Reduction in gas emission and environment demage.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 13.
Write about Bio-diversity impact Assesment and How will you anses its impact.
Answer:
Biodiversity Impact Assessment (BI A)

  • Biodiversity Impact Assessment can be defined as a decision supporting tool to help biodiversity inclusive of development, planning and implementation.

Bio-diversity Impacts can be assessed by

  • Change in land use and cover.
  • Fragmentation and isolation.
  • Extraction
  • External inputs such as emissions, effluents and chemicals.
  • Introduction of invasive, alien or genetically modified species.
  • Impact on endemic and threatened flora and fauna.

Question 14.
What is Geographic Information system? What are its importance?
Answer:
Geographic Information System

  • GIS is a computer system for capturing, storing checking and displaying data related to positions on Earth’s surface. Also to manipulate, analyse, manage and present spacial or geographic data.
  • GPS is a satellite navigation system used to determine the ground position of an object. It is a constellation of approximately 30 well spaced satellites that orbit the earth and make it possible geographic location.

Importance of GIS

  • Environmental impact assessment.
  • Disaster management.
  • Zoning of landslide hazard
  • Determination of land cove and land use
  • Estimation of flood damage.
  • Management of natural resources.
  • Soil mapping
  • Wetland mapping
  • Irrigation management and identification of volcanic hazard.
  • Vegatation studies and mapping of threatened and endemic species.

 Samacheer Kalvi 12th Bio Botany Guide Chapter 8 Environmental Issues

Question 15.
What is Remote sensing and what are its uses?
Answer:
Remote Sensing

  • Remote Sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance from the targeted area. It is an tool used in conservation practices by giving exact picture and data on identification of even a single tree to large area of vegetation and wild life.
  • Mapping of forest fire and species distribution.
  • Mapping ocean bottom and its resources.

Applications of Satellites

Name of the Satellites Year of Launch Application
SCATSAT-I Sep 2016 Weather forecasting, cyclone prediction and tracking services in India
INSAT 3DR Sep 2016 Disaster management