Introduction to Environmental Science(Lecture 01).pdf

the ppt mostly emplies about deep knowledge of environmental science

1. IntroductiontoEnvironmentalScience
Lecture By: TileksewBelay

2. Session I
•Course Introduction
•Lecture on Basics about Environmental Science

3. Course Objective:
•Introducingthebasicconcepts,elementsand
principlesofenvironmentscience.
•Toequipstudentstoexplorehumanrelationships,
perceptionsandpoliciestowardsenvironment.
•Discussthecurrentenvironmentalchallengesand
theappropriateplanning.

4. ✓Basics about environment (Definitions and Elements
of environment)
✓Concepts, objectives and principles of Environmental
Planning
✓Introduction of the current Environmental challenges
in cities
✓Sustainable development and Environmental Planning
✓The legal, economic, ethical and ecological issues in
environmental planning
✓The Environmental Planning Process
COURSE CONTENT

5. Course Delivery & Assessment
Delivery Assessment
✓Lecturing,
✓ReadingAssignment,
✓BookReviewand
✓Presentation.
✓Quizes-15%
✓Attendance-10%,
✓Mid Exam -25%,
✓Reading Assignment -15%,
✓Final Exam-35%

6. ❑introduction
What is Environment?

7. Environment:
▪Environmentisdefinedasasumtotalofallthe
livingandnon-livingelementsandtheireffects
thatinfluencehumanlife.
▪thesocialandculturalconditionsthataffectan
individualoracommunity.

8. Elements of Environment
Natural World Human World
▪plants,
▪animals,
▪soils,
▪air,and
▪water
•technology,
•socialinstitutions
•artifactsthatwe
createforourselves
using science,
technology,and
politicalorganization

10. Components of Environment

11. Components Environment
1.ecosystems and their constituent parts(including people
and communities and living organisms) and
2.all natural and physical resourceslike land, water and air;
3.those physical qualities and characteristicsof an area that
contribute to people's appreciation of its pleasantness,
aesthetic coherence, and cultural and recreational attributes
and
4.the social, economic, cultural conditionswhich affect the
matters stated in (a) to (c) or which are affected by those
matters.
5.the interacting natural and socialsystems.

12. Abiotic Factors

13. What is Environmental Science?

14. Environmental science
Environmentalscienceis
•thesystematicstudyofthe
interactionofnaturalandbuilt
worlds.
•Themainobjectiveofenvironmental
scienceistoimprovethewayhowto
useourworld/resource.

15. Environmental science
•Environmental science is the study of how humans interact with the
environment.
•Environmental science seeks to understand and solve environmental
problems by focusing on two primary areas of study.
•How we use natural resources such as water and plants
•How our actions alter our environment
•Environmental science is interdisciplinary, meaning that it integrates
many different fields of study.

16. Environmental science
Geography
Chemistry
Agriculture
BiologyEnvironmental
Science
Interdisciplinary

17. Environmental science
Interdisciplinary
Biology –the study of living organisms
Ecology, an important foundation of environmental science, is the study of how living things interact with
each other and with their abiotic environment.
Chemistry helps us understand changes in matter which occur in the environment such as the effect of
pollutants.
Geology helps us to understand the structure of the Earth and how certain pollutants may disperse if released
into the environment.

18. Environmental science
•Toapplythisinformationenvironmentalscientistsalsoincorporateknowledge
of
•social organization,
•politics, and
•the humanities.
That means environmental science is inclusive and holistic.

19. Environmental science
Environmentalscienceis,therefore,adisciplinethatisconcernedwiththe
understandingof
✓StructureandcompositionEnvironment
✓Processesthatoperatewithintheenvironment
✓functions(ecological,economic,andsocial)oftheenvironment
✓Environmentalvulnerabilitytohumanactivities

20. Environmental science
▪Theprimaryconcernofenvironmentalscienceis
exploringandlobbyingtechniquesforthesustainable
utilizationandmanagementofenvironmentalresources.

21. Structure of the Environment
Environment –is amultidimensional system that consists of four interacting
spheres.
•The Atmosphere,
•Lithosphere, Natural
•Hydrosphere, and the
•Ecosphere-biosphere
•AnthroposphereMan-made.

22. Environmental System
•Environment = biosphere, lithosphere, hydrosphere, atmosphereand their
interaction+ Anthroposphere.

23. Environmental System
Theenvironmentalsystemmaybeunderstoodasthesetofinteractionsbetweenthe
elementsofthe
•Biosphere/ecosphere,
•theatmosphere,
•thehydrosphere,
•thelithosphere

24. Nitrogen-
78%
Traces-
1%
Oxygen-
21%
Environmental System
❑Atmosphere:
•isthelayerofgasesretainedbyEarth's
gravitythatsurroundstheplanet.
•Theatmosphereisaprimemeanforthe
spatialdiffusionofpollutantsanda
temporarymeanoftheiraccumulation.
traces:includescarbondioxide,argon,water
Vaporandothercomponents.

25. is the layer ofgasesretained byEarth's gravitythat surrounds the planet.
▪Atmosphere

26. Atmosphere
1.Troposphere
•Thisisthefirstandthelowest
layerofEarth’satmosphere.
•Itstartsfromtheground(orsea
level)ofourplanetandexpands
upto10kmupinthesky.
•Alllifeonthisplanetisaffected
bythechangesthathappeninthis
layer,
•Alltheweatherchangestakeplace
inthetroposphere.

27. Atmosphere
2. Stratosphere
•Thislayergoesuparound50km
abovetheEarth’sground.
•theozonelayerthatisfoundinside
thestratosphere.
•moleculesofozonepreventus
fromultravioletlightfromthe
Sun

28. Atmosphere
3. Mesosphere
•Themesospheregoesupto85kmabovethe
surfaceofourplanet,
•Asthenamesuggests,itishalfwayupfrom
atmospherelayers
•Itwouldbeimpossibletobreatheinthe
mesospherebecauseoftoolowoxygenlevels
•Thislayeroftheatmospherehasthelowest
temperatureofalllayers,andtheydropdownto-
90°C.

29. Atmosphere
4. Thermosphere
•Thelayerthatislocatedbetween500
and1000kmabovetheEarth’s
•Thehighesttemperaturesismeasured
inthislayeroftheatmosphere,can
evenreach2,000°C!
•Thislayerisunderconstantattack
fromtheX-raysandUV
radiationcomingfromtheSun

30. Atmosphere
5. Exosphere
•Somewhereitisaround100,000km
abovesealevel.
•Theairhereisextremelythin,and
theconditionsherearemore
similartotheoneswefindwhen
weleavetheEarth’satmosphere
entirely.

31. Environmental System
❑Hydrosphere:
•Thehydrosphereistheaccumulationof
waterinallitsstates
•Itcoversaround71%oftheearth'ssurface
and
•isanimportantaccumulatorofpollutants
Ice-2%
Others-1%
Oceans-
97%
•Others:includesrivers,lakes,streamsand
undergroundwater

32. Environmental System
❑Lithosphere:
•TheLITHOSPHERE isthethincrustbetweenthemantle
andtheatmosphere.
•Althoughthelithosphereisaround100kmthick,only1kmof
itcanbeconsideredininteractionwiththebiosphere.
•Mainconstituentsarecrystallinestatesof

33. Environmental System
❑lithosphere :
•Thelithosphereisthemainsourceofpollutantsanda
permanentaccumulator.Someare
•naturallyreleasedthroughsourceslikevolcaniceruptions,
•whileotherslikefossilfuelsaretheresultofartificial
extractionandcombustion.

34. Environmental System
❑Biosphere:The Biosphere -ecosphererefers to the biologically
inhabited/ biologically active/ biotic partof the earth
that occurs at the interfaceof the
•Atmosphere,
•Lithosphereand
•Hydrosphere.

35. Functionsof the environment
❖Atmosphere:
▪shelter,
▪air,
▪rain,
▪temperatureregulation,
▪energyand
▪supportsnaturalandsocio-economicprocesses.
Theatmosphere–provides:

36. What is the merits of Environment?

37. Functionsof the environment
❖Hydrosphere:Thehydrosphere–provides:
•water,
•habitatformuchofbiodiversity,
•regulatestemperatureand
•supportsseveralotherphysical,biologicalandsocio-
economicsystems.

38. Functionsof the environment
❖Lithosphere:
•land,
•soil,
•subsurfaceforlife
•,minerals,
•heatsink,
•watersink,
•isakeycomponentformeteorologicalprocesses.
TheLithosphere–provides:

39. Functionsof the environment
❑Biosphere:•TheBiosphere-ecosphereisthesetofalllivingorganisms,
includinganimalsandplants.
•Theyaretemporaryaccumulators(likelead)and
•sourcesforpollutants(naturalforestburning)inavery
complexsetofrelationshipswiththeatmosphere,
hydrosphereandlithosphere.

40. Our Environment Through Time
•Hunter-gatherersocietiesconsistofpeoplewhoobtainfoodby
collectingplantsorhunting(orscavenging)wildanimals.
•Hunter-gatherersocietiestendtobesmallgroupsthatmigratewithanimals
oraccordingtoseason
•Afewhunter-gatherersocietiesremaintodayinpartsoftheAmazonand
NewGuinea
•EvidencesuggeststhatNativeAmericansburnedtheprairiestokeeptrees
fromgrowingonthemsothattheywouldbebettersuitedforhunting
•Evidencealsolinksthearrivalofmaninmanyplaceswiththeextinctionof
largemammalssuchasmammothandgiantgroundsloth

41. Our Environment Through Time
•Agricultureis the practice of growing, breeding, and caring for the
plants and animals that are used for food, clothing, housing,
transportation, and other purposes.
•The agricultural revolution began over 10,000 years ago in many parts of the
world and had a major effect on population and the environment
•A given area of land can support up to 500 times as many people with
agriculture than it can through hunting and gathering
•As populations grew, they began to concentrate in certain areas

42. Our Environment Through Time
•Agriculture is the practice of growing, breeding, and caring for the
plants and animals that are used for food, clothing, housing,
transportation, and other purposes.
•The plants and animals that we depend on agriculturally today began as wild
populations and were selected through the ages for their desirable traits
•Slash-and-burnagriculture was an early form of converting natural habitat to
farmland
•Civilizations have fallen due to the destructive consequences (erosion,
flooding, degradation of soil quality, etc.) of poor agricultural technique

43. Our Environment Through Time
•The focus of the Industrial Revolution, which began about 300 years
ago, was the change of fuel source from animal and water power to the
combustion of fossil fuels.
•Agriculture, industry, and transportation became much more efficient –
enough so to revolutionize society
•Large scale production meant more and cheaper goods and agriculture
depended less on large numbers of laborers
•Motorized vehicles allowed for the cheap transportation of people and goods
over long distances

44. Our Environment Through Time
•The focus of the Industrial Revolution, which began about 300 years
ago, was the change of fuel source from animal and water power to the
combustion of fossil fuels.
•Along with improvements in lifestyle, the Industrial Revolution has introduced
many new environmental problems
•Pollution and habitat loss are becoming greater concerns as human population
continues to increase exponentially

45. Thank you!
Questions?