UNIT-1-The-Biosphere-Past-Present. Ecology

Terrestrial Ecology

1. THE BIOSPHERE –
PAST AND PRESENT

2. LearningOutcomes
1.Tracetheoriginofthebioticandabiotic
componentsofthebiosphere.
2.Determinehowthedifferentmilestonesleadto
thedevelopmentofthefirstterrestrialecosystem.
3.Demonstrateunderstandingonthemajorbiomes
oftheworld.
2

3. ABrief History of Life on Earth
3
Manyrenownedscientistsinthepastwerepuzzledwiththe
questionaboutlifeonEarth,like:
•Whyaretheresomanydifferentspeciesontheplanet?
•TheageofEarth?
•HowthePlanetEarthforms?
•WhatarethefirstorganismsemergedinPlanetEarth?

4. UNIFYING THEORIES OF BIOLOGY
4
•CellTheory(Schleiden1838,Schwann1839,Virchow1858)
“Allorganismsaremadeupofcells,andthesecellscomefrom
pre-existingcells.”
•Biogenesis(Pasteur1865)
“Lifecomesonlyfromlife.”
•Evolution(Darwin1858)
“Alllivingthingshaveacommonancestorandareadaptedtoa
particularwayoflife.”
•Gene(Mendel1866)
“Organismscontaincodedinformationthatdictatestheir
structure,function,andbehavior.”

5. THEORIESON THE ORIGIN OF LIFE
5
•DivineCreationTheory
-BasedonthebookofGenesisintheBible
-lifeisbelievedtohavebeencreatedbytheAlmightyGod.
•AbiogenesisorspontaneousGenerationTheory
-Lifeoriginatedspontaneouslyfromnon-livingthings.
•PhilosophicalTheoryofEternity
-lifehasnobeginningandnoend;lifehasbeenhererightfrom
theverybeginningoftime.

6. THEORIESON THE ORIGIN OF LIFE
6
•BigBangTheory(GeorgesLemaître,1931)
-alsocalledphysico-chemicalorcosmologicaltheory.
-Heavenlybodies,includingtheearth,originatedfromthe
explosionofahotrotatingballofgasandeventuallylifewas
formedfromthechemicalevolutionofdifferentcompounds
presentintheprimitiveearth.

7. THEORIESON THE ORIGIN OF LIFE
7
•Whatdoyoumeanwhenyousaythatsomethingisalive?
•Biologistshavenotbeenabletoagreeonasimple
definitionoflife.Buttheyagreedonwhatthesignsoflife
are.
•Eachlivingthingiscalledanorganism.Allliving
organismshavethesamebiologicalcharacteristics.

8. CHARACTERISTICS OF LIVING ORGANISMS
8
Metabolism–thesumtotalofallthephysicalandchemical
changesundergoingwithintheorganism.
-couldbeanabolism(buildingupprocess)or
catabolism(breakingdownprocess)
Growth–thecapacitytoincreaseitssize.
Animalshavelimitedgrowthascomparedwith
plants.Someplantshaveacontinuesgrowth
throughouttheirlife.
Irritability–referstotheabilitytoreacttoanyenvironmental
changeorstimulusthatoftenresultsinmovement.

9. CHARACTERISTICS OF LIVING ORGANISMS
9
ReproductionandDevelopment–alllivingthingsarecapable
ofreproductiontoensurethesurvivalofspecies.
Adaptation–referstomodificationthatpromotethelikelihood
ofsurvival.
Organization–partsoflivingthingsarearrangedina
particularway.

10. LEVELS OF BIOLOGICAL
ORGANIZATION
10

11. 11

12. 12
Atom-smallestparticleofmatter
LEVELS OF BIOLOGICAL ORGANIZATION

13. 13
Molecules–twoormoreatomsheldtogetherbychemical
bonds.
LEVELS OF BIOLOGICAL ORGANIZATION

14. 14
Cell-unitoflifecapableof
carryingoutallthefunctions
oflivingthings.Thewordcell
comes from the latin
“cellulae”meaning small
rooms.
LEVELS OF BIOLOGICAL ORGANIZATION
Nerve Cell

15. 15
Tissue–agroupofsimilarcellsthatfunctiontogethertodo
aspecificjob.Theword“tissue”takesrootfromtheFrench
word“tisser”(toweave),
LEVELS OF BIOLOGICAL ORGANIZATION
Nervous
Tissue

16. 16
Organ–agroupofdifferent
tissuesthatfunctiontogether
foraspecificpurpose.
LEVELS OF BIOLOGICAL ORGANIZATION

17. 17
Organsystem–agroupof
severalorgans working
together toperform a
function
LEVELS OF BIOLOGICAL ORGANIZATION

18. 18
LEVELS OF BIOLOGICAL ORGANIZATION
Organism–anybiologicalentitysuchasplant,animal,
fungi,orbacteria.

19. 19
LEVELS OF BIOLOGICAL ORGANIZATION
Population–adistinct
groupofindividualsofthe
samespeciesthatliveand
interactinthesame
geographicarea

20. 20
LEVELS OF BIOLOGICAL ORGANIZATION
Community–anassemblageof
differentpopulationsthatliveand
interactwithoneanotherinagiven
areaoragiventime.Interactions
varyinnaturesuchascompetition,
predation,mutualism,etc.

21. 21
LEVELS OF BIOLOGICAL ORGANIZATION
Ecosystem-acommunityoforganismsinanarea,aswellas
thenonlivingfactorsoftheenvironment.

22. 22
LEVELS OF BIOLOGICAL ORGANIZATION
Biosphere–itisthepartof
earthwherelifeisexisting

23. GEOLOGIC TIME
Fossils & The Geologic Time Scale
23

24. GEOLOGIC TIME SCALE
24
Earth’sageisbelievedtobe4.6billionyears
Itisbrokendownintodifferentunitsandsub-unitsbased
upontherocksandfossilswithinthoserocklayers
Largestdivision=EON(ex:Archean,Phanerozoic)
Nextlargest=ERA(ex:Mesozoic,Cenozoic)
Nextlargest=PERIOD(ex:Devonian,Jurassic)
Smallestdivision=EPOCH(ex:Miocene,Pleistocene)

25. GEOLOGIC TIME SCALE
25
•MajorUnitsofTimeScalewere
firstconstructedinthe1800s
•Names ofthesetimeswere
usuallygivenbynamingthem
aftergeographicregionswhere
therocksfromthattimewere
firststudied(ex.Pennsylvanian)
•Noabsolutedatingatthattime,
sothewholethingwasoriginally
doneusingrelativedating
•Onceradiometric datingwas
discovered,thetimeswereputin
placeandarecontinuallybeing
checkedandrefined

26. GEOLOGIC TIME SCALE
26
•ThePrecambrian (eon)is
madeupof3largeeons
totalingover4Byrs:
•Hadean–“hell-like”
•Archean–“ancient”
•Proterozoic–“firstlife”
•Anyinformationfromthis
timeperiodissketchy
•Erosionhasdestroyedmost
oftherocksandfossils
•Any fossilsthat have
survivedarerareandsimple
instructure

27. 27

28. 28
Hadean—Hellfire&Brimstone
•From4600–3800Mya
•Theformationofthesolar
system through planetary
bombardment
•Sunwas70%asbright
•Massivevolcanismproduces
the young atmosphere
probablymadeupofCO2,
H2O,CH4,&NH3
•Nofossilsfoundthisold
GEOLOGIC TIME SCALE-PRECAMBRIAN

29. 29
Archean–oldestrocks
•From3800–2500Mya
•Surfaceoftheearthturnsfrom
moltentosolidrock
•Oceansformfromwatervapor
condensation
•Oldestrocksknownhavebeen
datedtothiseon
•Potentiallythefirstsimple
bacteria/algaefossils
•Noxiousatmospherewasvery
depletedofoxygen
•Continentsbegintoform
GEOLOGIC TIME SCALE-PRECAMBRIAN

30. 30
Proterozoic–bigchanges
•From2500–570Mya
•LargestEon(~2Byrstotal)
•Atmosphere enricheswith
oxygenduetobacteria—ozone
layerformstoo(good)
•SupercontinentRodiniaforms
around800Mya
•Firstmulti-cellfossils–simple
•Stromatolites(algae)
•Eukaryoticcellfossils
•Extensiveglaciationsduring
“SnowballEarth”
GEOLOGIC TIME SCALE-PRECAMBRIAN

31. GEOLOGIC TIME SCALE
31
Phanerozoic–“visiblelife”
•ThreeErasspanningfrom570
Myatopresent
•Paleozoic–“ancientlife”
•Mesozoic–“middlelife”
•Cenozoic–“recentlife”
•Greatestdiversityoflandand
oceanorganisms
•Fossil record indicates
complexorganismsthrive
•Severalmassextinctions
•Wearestillcurrentlylivingin
thePhanerozoic

32. 32

33. 33
Paleozoic – “Cambrian
Explosion”
•Spans570–245Mya
•7periodsofPaleozoic
•Cambrian, Ordovician,
Silurian, Devonian,
Mississippian,Pennsylvanian,
Permian
•Atthebeginningofthe
Cambrian,thefossilrecord
goesthroughanexponential
increaseindiversityand
complexity
GEOLOGIC TIME SCALE-PHANEROZOIC

34. 34
Paleozoic–morespecifics
•3distinct“ages”
•Ageofinvertebrates(shells)
•Ageoffishes(vertebrates),
•Ageofamphibians
•Trilobites,seedferns,&amphibiansare
majorindexfossilsofthePaleozoic
•Massiveswampsresultingincoaldeposits
oftoday
•SupercontinentsLaurasia,Gondwanaland,
andeventuallyPangaeaform
•Disastrousextinctionattheendofthe
Permianwipingout~90%ofallmarine&
~70%ofalllandorganisms
GEOLOGIC TIME SCALE-PHANEROZOIC

35. 35
Mesozoic–RiseofDinosaurs
•Mesozoichas3Periodsfrom
245–66Mya
•Triassic
•Jurassic
•Cretaceous
•Pangaeabeginstobreakapart
and form the current
continents
•Warmerclimatesdominate
•Gymnosperms (non-flowering,
naked seed)appear and
becomethedominantplant
GEOLOGIC TIME SCALE-PHANEROZOIC

36. 36
Cenozoic–RiseofMammals
•2Periodsspanningfrom66Myato
presentday
a.Tertiary
b.Quaternary
•7Epochsarecontainedwithinthe
twoperiods
•Paleocene, Eocene, Oligocene,
Miocene,Pliocene,Pleistocene,&
Holocene
•WearenowintheHolocene
•Cenozoichasthefossilsofthe
organismswhichwereableto
surviveandadaptaftertheK/T
extinction
GEOLOGIC TIME SCALE-PHANEROZOIC

37. 37
Cenozoic–morespecifics
•Cenozoicrepresentslessthan2%
ofEarth’shistory
•Mammals riseandbecomethe
dominantorganismonland
•Angiosperms(flowers)becomethe
dominantplantlifeonland
•Thisprobablyhelpedtoallowthe
riseofbirdsandmammals who
bothfeedonflowersandplants
•Iceageadvancesoccurduring
Pleistocene
•Manyorganismsgoextinctwith
iceageclimatechanges
GEOLOGIC TIME SCALE-PHANEROZOIC

38. EON ERA
Millions of Years Ago (Mya)
Phanerozoic Eon
Cenozoic 66
Mesozoic 245
Paleozoic 570
Precambrian Eon
Proterozoic
Late Proterozoic 900
Middle Proterozoic 1600
Early Proterozoic 2500
Archean
Late Archean 3000
Middle Archean 3400
Early Archean 3800
Hadean 4600

39. EON ERA PERIOD EPOCH
Millions of Years
Ago (Mya)
Phanerozoic
Cenozoic
Quaternary
Holocene 0.01
Pleistocene 1.6
Pliocene 5.3
Tertiary
Miocene 23.7
Oligocene 36.6
Eocene 57.8
Paleocene 66.4
Mesozoic
Cretaceous 144
Jurassic 208
Triassic 245
Paleozoic
Permian 286
Carboniferous
Pennsylvanian 320
Mississippian 360
Devonian 408
Silurian 438
Ordovician 505
Cambrian 570
P R E C A M B R I A N T I M E . . .

40. 40
4.4-0m.y.a.:Hominidsdivergedfromanearlyape-likefamily.
(Poorfossilrecordandmissingtransitionalformscomplicatethe
storyandleavemanygaps,butnewfossilsarebeingfoundeach
year.)
Ardipithecusramidus-4.4(bipedal,erectforestdweller)
Ardipithecusanamensis-4.2-3.9(bipedal,apelikeskull)
Australopithecusafarensis(“Lucy”)-3.9-2.8(bipedal,apelike
facewithslopingforehead,human-likebodies.Livedtogetherin
familygroups.)andotherspeciesofAustralopithecus-3.0-1.1
Homohabilis-2.2-1.6m.y.a.(usedstonetools,so
mayberelatedtoHomosapiens,butskullislike
australopithecines)
FOSSIL RECORD-QUARTERNARY

41. 41
Hominids
Homoerectus-1.8-0.4m.y.(Pekingman,
Javaman:developedlargebrains,tools,
weapons,fire,andlearnedtocookfood.)
Homosapiensarchaic-500-200t.y.a.
(SkullsintermediatebetweenHomoerectus
andHomosapienssapiens)
Homosapiensneanderthalensis-200-30t.y.a
(teethandbrainsimilartoours,
butDNAdifferent,burialsitessuggest
theypracticedsomeformofreligion.)
FOSSIL RECORD-QUARTERNARY
Neandertal

42. LearningOutcomes
1.Tracetheoriginofthebioticandabiotic
componentsofthebiosphere.
2.Determinehowthedifferentmilestonesleadto
thedevelopmentofthefirstterrestrialecosystem.
3.Demonstrateunderstandingonthemajorbiomes
oftheworld.
42

43. ECOSYSTEM
43

44. 44
Ecosystem-a
community
oforganisms
inanarea,as
wellasthe
non living
factorsofthe
environment.
WHAT IS AN ECOSYSTEM?

45. 45
Anecosystemreferstoalltheanimalsandplantsfoundin
oneplace,andthewaytheyalllivetogether.
•Differentplantsandanimalsliveindifferent
ecosystems.
•Differentecosystemscanbeclosetogether.
•Someanimalsbelongtoseveralecosystems.
•Everythingthataffectsananimalmakesupits
environment-whereitlives,theweatherandallthe
livingthingsitcomesintocontactwith
•Everylivingthing,includingpeople,hasaneffectupon
theenvironment.
WHAT IS AN ECOSYSTEM?

46. 46
WHAT IS AN ECOSYSTEM?

47. 47
WHAT IS AN ECOSYSTEM?
Abiotic and
biotic
components
ABIOTIC
BIOTIC
non-living components in the environment…
Light, water, wind, nutrients in soil, heat, solar radiation,
atmosphere, etc.
Living organisms…
Plants, Animals, microorganisms in soil, etc.

48. 48
WHAT IS THE DIFFERENCE BETWEEN NICHE
& HABITAT?
48
HABITAT
NICHE
placewherecommunitieslive.
Roleorfunctionofanorganism
withinanecosystemorhabitat
PRODUCERS CONSUMERS PREDATORS

49. 49
Different Roles (niche) of the Biotic Components
PRODUCERS
CONSUMERS
DETRITIVORES
Producers-autotrophs (self-feeders)
greenplantsetc.&otherorganismsthat
manufactureorganiccompounds.
feedonproducersalsocalled
heterotrophsorotherfeeders;
feedondeadorganicmatter,detritus
feedersanddecomposers

50. 50
AUTOTROPHS
Organismswhichcansynthesistheirowncomplex,energy
rich,organicmoleculesfromsimpleinorganicmolecules
(e.g.greenplantssynthesissugarsfromCO2andH2O)
couldbechemoautotrophs (bacteria),obtainingenergyby
oxidizing inorganic compounds to synthesize
carbohydrates,oraphotoautotrophs (plants),obtaining
energyfromlighttosynthesizecarbohydrates.
Different Roles (niche) of the Biotic Components

51. 51
HETEROTROPHS
Organismswhomustobtaincomplex,energyrich,organic
compoundsformthebodiesofotherorganisms(deador
alive)
Different Roles (niche) of the Biotic Components
HERBIVORES CARNIVORES
OMNIVORES DETRITIVORES
TYPES OF
HETEROTROPHS

52. 52
WHAT IS AN ECOSYSTEM?
TYPE OF
ECOSYSTEM /
BIOME
WATER / AQUATIC
LAND / TERRESTRIAL

53. WATER BIOMES
53

54. 54
Majoraquaticbiomes
canbecharacterizedby
their physical
environment, chemical
environment,geological
features,photosynthetic
organisms, and
heterotrophs
AQUATIC BIOMES

55. 55
Planktons are the
organismsthatfloatnear
thesurfaceofthewater.
Twotypesofplankton
aremicroscopicplants
calledphytoplankton,
andmicroscopicanimals
called zooplankton.
Phytoplankton produce
mostofthefoodforan
aquaticecosystem.
Classification of organisms present in AQUATIC ECOSYSTEM

56. 56
Plankton are
microscopic algae,
plants, and other
organismsthatfloaton
thesurfaceofwater
biomes.
Classification of organisms present in AQUATIC ECOSYSTEM
Theyneedsunlightto
survive.

57. 57
Phytoplankton are
importantproducersin
waterbiomes.
Classification of organisms present in AQUATIC ECOSYSTEM
Theyarethefirststep
inmanyaquaticfood
chains

58. 58
Nekton are free-
swimming organisms,
suchasfish,turtles,and
whales.
AQUATIC ORGANISMS

59. 59
Benthos arebottom-
dwellingorganisms,such
asmussels,worms,and
barnacles.Manybenthic
organismsliveattached
tohardsurfaces.
AQUATIC ORGANISMS

60. 60
•Amountofsalt(salinity)
•Amountofdissolvedoxygen
•Sunlight
•Temperature
•Nutrient
THE LIMITING FACTORS IN WATER BIOMES

61. 61
FreshwaterEcosystem
•RiversandStreams
•LakesandPonds
Saltwater/MarineEcosystem
•Ocean
•Estuaries
•Seashores(tidalareas)
TYPES OF WATER BIOMES

62. 62
Freshwater contains
littleornosalt,soithas
aLOWsalinity.
Flowingfreshwater=
rivers and streams
(LOTIC)
StillFreshwater=lakes
andponds(LENTIC)
FRESHWATER BIOMES

63. 63
Flowingfreshwater(LOTICwater)
Streams
Thefasterastreamflowsthe
greatertheamountofdissolved
oxygeninit.
Fasterwaterflows=oxygen
FRESHWATER BIOMES

64. 64
Flowing freshwater (LOTIC water)
Rivers
Watermovesslowerinariverand
debrissettlesonthebottom.
Becauseofthis,riverstendto
havemorenutrientsandless
dissolvedoxygen.
nutrientsand oxygen
FRESHWATER BIOMES

65. 65
Stillfreshwater(LENTICwater)
Ponds
Small,shallowbodiesofwater
Sunlightpenetratesallthewayto
thebottom
Mostcompletelyfilledwithplant
material.
nutrients
FRESHWATER BIOMES

66. 66
Estuaries(Wetlands)
•Areawherearivermeets
anocean
•Mix of salt and
freshwater
•Locatednearcoastlines,
borderland
•Extremelyfertile
•Nutrientlevelsarehigher
thanbothsaltand
freshwater
SALTWATER BIOMES-MARINE ECOSYSTEM

67. 67
Seashores
•Tideshaveahuge
influenceonlife
here
INTERTIDAL ZONE-
portionoftheshoreline
thatiscoveredwith
waterathightideand
exposedtotheairat
lowtide.
SALTWATER BIOMES-MARINE ECOSYSTEM

68. 68
Ocean
Canbedividedinto2mainlifezones
1.Photiczone-sunlightpenetrates
2.Aphoticzone-NOsunlight
SALTWATER BIOMES-MARINE ECOSYSTEM

69. 69
1.Photiczone-above200m
Madeupoftheeuphotic&
disphoticzones
Sunlightpenetrates
Plantlifeandanimallifeis
abundant
SALTWATER BIOMES-MARINE ECOSYSTEM

70. 70
2.Aphoticzone-below
200m
SunlightDOESNOTpenetrate
Therearenoplants
Animal lifeishighly
specialized
SALTWATER BIOMES-MARINE ECOSYSTEM

71. 71
2.Aphoticzone-below
200m
Manyoftheinhabitantofthe
deepoceanhaveaspecial
adaptation known as
bioluminescence
SALTWATER BIOMES-MARINE ECOSYSTEM

72. LAND BIOMES
72

73. 73

74. 74
TUNDRA-“THE COLD DESERT”
•Foundatlatitudesaroundthe
NorthPole
•Lessthan25cmprecipitation
yearly
•Verycoldyearround(-40ºC
inwinter)
•Cold,dry,treelessregion
LAND BIOMES-TERRESTRIAL ECOSYSTEM

75. 75
TUNDRA-“THE LAND OF
MIDNIGHT SUN”
•Winterlasts6to9months
withnodaylight
•Summerisshortandcoldwith
24hoursofsunlightaday
LAND BIOMES-TERRESTRIAL ECOSYSTEM

76. 76
TUNDRA
•Soilispoor
•Permafrost
•Layer of
permanently
frozensoil
LAND BIOMES-TERRESTRIAL ECOSYSTEM

77. 77
TAIGA-CONIFEROUS FOREST
•World’slargestlandbiome
•Latitudesbetween50ºNand
60ºN
•Warmerandwetterthanthe
Tundra
•Wintersarelongandcold
•35to40cmofprecipitation
yearly(mostlysnow)
LAND BIOMES-TERRESTRIAL ECOSYSTEM

78. 78
TEMPERATE DECIDOUDS
FOREST
•Foundbelow50ºNlatitude
•75to150cmprecipitation
yearly
•Widerangeoftemperatures
with4seasons
•Belowfreezinginwinterto
30ºCinsummer
LAND BIOMES-TERRESTRIAL ECOSYSTEM

79. 79
TEMPERATE DECIDOUDS
FOREST
•Soilisrichinnutrientsfrom
layersofdecomposingleaves
LAND BIOMES-TERRESTRIAL ECOSYSTEM

80. Rainforest
•dense, lush, and highly biodiverse
forest biomecharacterized by high
levels of rainfall and a warm climate.
•different layers of a rainforest
include emergent, canopy,
understory, and forest floor

81. 81
Layers of the Rainforest
Emergent
Canopy
Understory
Forest floor

82. Layers
Emergent
Canopy
Understory
Forest floor

83. Emergent
Layers
•topmost layer of the forest,
consisting of the tallest trees that
rise above the general canopy
•typically 50 to 70 metersabove
the ground

84. Emergent
Layers
•receive the most sunlight and are
often exposed to strong winds
and rain
•home to species adapted to high
winds and bright light
•examples include mahogany and
silk cotton tree

85. Canopy
Layers
•layer just below the emergent
layer, forming a dense, continuous
cover of tree branches and leaves
•typically 30 to 50 metersabove
the ground

86. Canopy
Layers
•majority of animals and plants live
in the second layer of the
rainforest
•it protects the forest floor from the
intense heat of the sun, heavy
rains, and dry winds.

87. Canopy
Layers
•essential in maintaining the
regional and global climate.
•main site of heat, water vapor,
and atmospheric gas interchange.

88. Understory
Layers
•only receive 5% of the rainforest’s
sunlight, and their leaves tend to
be large.
•characterized by a dense network
of shrubs and small trees.

89. Understory
Layers
•typically 10 to 30 meters above
the ground
•home to various species of birds,
insects, and reptiles that thrive in
the low light and humidity.

90. Understory
Layers
•Plants like palms and ferns are
common in the understory layer

91. Forest floor
Layers
•bottom layer of the forest, where
the ground is covered with
decomposing plant material and
where sunlight is minimal

92. Forest floor
Layers
•only receives 2% of the sunlight,
making it dark, damp, and hot
•within the forest floor,
decompositionoccurs.

93. Forest floor
Layers
•supports decomposers like fungi,
bacteria, and invertebrates, as
well as some larger animals such
as ants, beetles, and ground-
dwelling mammals.

94. Forest floor
Layers
•Many plants in this layer are
adapted to low light conditions
and include mushrooms,
mosses, and small shrubs.

95. Forest floor
Layers
•common vegetation includes
mosses, lichens, and leaf litter

96. 96
TROPICAL RAIN FOREST
•Foundneartheequator
•Abundantprecipitation
•Hotandhumidallyear
LAND BIOMES-TERRESTRIAL ECOSYSTEM

97. 97
GRASSLAND
•Anareathatispopulated
mostlybygrassesandother
non-woodyplants
•Receive25to75cmofrain
peryear
•Firesanddroughtsare
common
LAND BIOMES-TERRESTRIAL ECOSYSTEM

98. 98
Grasslands are known by many names
U.S.A. –Prairie or Plains
Asia –Steppe
South America –Pampas
Africa –Veldt or Savanna
Australia -Savanna
LAND BIOMES-TERRESTRIAL ECOSYSTEM

99. 99
Desert
•Found on every continent.
•The driest biome on Earth
•Extreme temperatures-
Very hot during the day
and cool at night
•Very little rainfall
•Less than 25 cm
precipitation yearly
LAND BIOMES-TERRESTRIAL ECOSYSTEM

100. 100
ANY QUESTION?

101. What is
Terrestrial Ecology?
Terrestrialecologyisthestudyofland-
basedecosystems,theirpopulationsand
communitiesofplants,animals,and
microbes,theirinteractionswiththe
atmosphere andwithstreamsand
groundwater,andtheirroleinthecycling
ofenergy,water,andthemajor
biogeochemicalelementssuchascarbon
andnitrogen.

102. What is
Terrestrial Ecology?
Thetypeofterrestrialecosystemfound
inaparticularplaceisdependenton
thetemperaturerange,theaverage
amountofprecipitationreceived,the
soiltype,andamountoflightit
receives.

103. Factors
affecting
TERRESTRIAL
ECOLOGY
ABIOTIC
BIOTIC
non-living components in the
environment
Light, water, wind, nutrients in soil,
heat, solar radiation, atmosphere,
etc.
Living organisms
Plants, Animals, microorganisms in
soil, etc.

104. Factors
affecting
TERRESTRIAL
ECOLOGY
LIGHT
Lightaffectslivingthingsintermsof
intensity,qualityandduration.Light
intensityandqualityaffects
photosynthesis,floweringand
germinationofplantswhilein
animals affects migration,
hibernationandreproduction.
Aphotographiclightmeterisused
tomeasurelightintensitywhilethe
seechidiscmeasures light
penetrationinwater.
ABIOTIC

105. Factors
affecting
TERRESTRIAL
ECOLOGY
TEMPERATURE
Biochemicalprocessesofmost
organismsfunctioneffectively
withinanarrowrangeof
temperature.Temperaturevaries
duetoseasons,altitude,latitude
andalsodiurnallyespeciallyinhot
deserts.
Thisthereforeaffectsthe
distributionoforganismsina
habitat.Temperaturevariations
influencethedistributionof
organismsmoreinterrestrial
habitatsthanaquatichabitats.
ABIOTIC

106. Factors
affecting
TERRESTRIAL
ECOLOGY
ATMOSPHERIC PRESSURE
Theatmospherehasadefinite
weightandsoitexertspressureon
theearth.Onthesurfaceofthe
earth,atmosphericpressurevaries
withaltitude.
Pressuredecreaseswithincreasing
altitude.Athigherelevations,there
arefewerairmoleculesabovea
givensurfacethanasimilarsurface
atlowerlevels.
The pressure at any level in the atmosphere may be interpreted as the
total weight of the air above a unit area at any elevation.
ABIOTIC

107. Factors
affecting
TERRESTRIAL
ECOLOGY
HUMIDITY
Referstotheamountofwater
vaporintheatmosphere.When
humidityishighthereismuchwater
vaporinair.
Humidityaffectstherateatwhich
waterevaporatesfromthesurface
oforganismssuchasin
transpirationorsweating.Thisin
turnaffectstheirdistributionon
earth.
Slingshotpsychrometerisusedin
measuringrelativehumidity.
ABIOTIC

108. Factors
affecting
TERRESTRIAL
ECOLOGY
WIND
Windismovingair.Itincreasesthe
rateofwaterlossfromthe
organisms,thereforeaffectingtheir
distribution.
Awindvaneorwindsockisusedto
determinethedirectionofprevailing
wind.
Anemoterisusedtomeasurethe
speedofwind.
ABIOTIC

109. Factors
affecting
TERRESTRIAL
ECOLOGY
SALINITY
Itreferstothesaltconcentrationof
water,causingadivisionofthe
aquaticenvironmentintomarine,
estuarineandfreshwater.
Salinitymeterisusedinmeasuring
saltconcentrationinasolution.
ABIOTIC

110. Factors
affecting
TERRESTRIAL
ECOLOGY
pH
pHisthemeasureofhowacidicor
alkalinewaterisinaquaticanimals
orsoilsolution.Itinfluencesthe
distributionofplantsandanimalsin
soilandfreshwaterponds.Some
plantsdrivewellinacidicconditions
whileothersinalkalineconditions.
pHmeter/pHpaperisusedin
determininghowacidic,basic,or
alkalineawater/solutionis.
ABIOTIC

111. 111
ANY QUESTION?

112. 112
1.Identify the factors that cause local
variations of climate.
Assignment