module 2 environmental studies /Ecosystem

Ecosystem
Kerala university BBA module 2 environmental studies.

1. Ecology
CoinedbyHonsReiterandHaekel(1869)
OriginatedfromtwoGreekwords
Oikos(eco)–means“house”(or)placeofliving
Ologymeans“thescienceof(or)thestudyof.
•Studyofinteractionsamongorganisms(or)
groupoforganismswiththeirenvironment.
•Ecologyisthestudyofecosystems.
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2. Ecosystem
•BritishecologistA.G.Tansleycoinedin1935
•Agroupoforganismsinteractingamong
themselvesandwithenvironmentisknownas
ecosystem.
•Asystemofinteractionoforganismswith
theirsurroundings(i.e.,environment)iscalled
as“ecosystem”.
•Ex:Pond,lake,ocean,forestanddesert….
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3. CHARACTERISTICS OF ECOSYSTEM
1.Basicfunctionalunitofecology.
2.Containsbothbioticandabioticcomponents.
3.Thefunctionofecosystemisrelatedtothe
cyclingofmatter(materials)andflowof
energy.
4.Theamountofenergyneededtomaintainan
ecosystemdependsonitsstructure.
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4. CLASSIFICATION OF ECOSYSTEM
•Mainly2types
1.NaturalEcosystem
2.ArtificialEcosystem
NATURAL ECOSYSTEM:
a)Developedandgovernedbynature.
b)Thesearecapableofoperatingandmaintaining
themselveswithoutanymajorinterferencebyman.
Twotypesofnaturalecosystembasedontheirhabitat.
1.TerrestrialEcosystem.
2.AquaticEcosystem.
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5. 1)Terrestrial Ecosystem:
Thisecosystemisrelatedtoland.
Examples:Grasslandecosystem.Forest
ecosystem,andDesertecosystemetc.
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2)AquaticEcosystem:
Relatedtowater
Subdividedintotwotypesbasedonsaltcontent.
i.Fresh Water Ecosystem:
a.RunningWaterEcosystems
Ex:Rivers,streams(smallnarrowrivers)
b.StandingWaterEcosystems
Ex:Pond,lake&well,etc
ii. Marine Ecosystem:
Ex:seasandseashores

7. MAN MADE /ARTIFICIAL ECOSYSTEM:
Created and maintained by man for his different
needs.
Ex: Reservoirs, Artificial lakes and gardens, etc.
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8. STRUCTURE /COMPONENTS OF AN
ECOSYSTEM:
•Structureofanecosystemexplainsthe
relationshipbetweentheabiotic(non-living)
andthebiotic(living)components.Ea
•Eachandeveryecosystemhastwomajor
componentsare:
1. Biotic (living) components.
2. Abiotic(Non-living) components.
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10. Biotic Components:
The living component of an ecosystem is called
“Biotic component”.
Ex: Plants (Producers)
Animals (Consumers)
Micro Organisms (Decomposers)
classified into three types based on how they get
their food.
A. Producers (Autotrophs) : Plants
B. Consumers (Heterotrophs) : Animals
C. Decomposers (Saprotrophs) : Micro organisms.
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11. A.Producers(or) Autotrophs
(Auto=self,troph=feeder)
Selffoodproducingorganismsareknownas
autotrophs.
Ex:Allgreenplantsandtrees.
Producerssynthesizetheirfoodthemselves
throughphotosynthesis.
Hencetheyarealsocalled“Photoautotrophs”.
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12. B.Consumers(or) Heterotrophs
(Hetero=other,troph=feeder)
Cannotpreparetheirownfoodanddependdirectly(or)
indirectlyontheproducers.
Dependinguponthefoodhabitstheconsumersare
dividedintofourtypes
.i.Herbivores(or)PrimaryConsumers(PlantEaters)
ii.Carnivores(or)SecondaryConsumers(MeatEaters)
iii.Omnivores(or)TertiaryConsumers(Withplant&
meateaters)
iv.Detritivores(deadorganismeaters)
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13. C.Decomposers(or) Saptrotrophs:
Decomposersattackthedeadbodiesof
producersandconsumersanddecomposethem
intosimplecompounds.
Duringthedecompositioninorganicnutrients
arereleased.
Theorganismswhichbreakdownthecomplex
compoundsintosimpleproductsarecalled
decomposers(or)reducers.
Ex:micro-organismssuchasbacteriaandfungi,
etc.
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14. AbioticComponents:
Thenon-livingcomponentofanecosystemis
called“abioticcomponent”
Thesenon-livingcomponentsenterthebodyof
livingorganism,takepartinmetabolicactivities
andthenreturntotheenvironment.
Includes:
1.Climatefactors:Solarradiation,temperature,
wind,watercurrent,rainfall,etc.
2.Physicalfactors:light,fire,soil,air,etc.
3.Chemicalfactors:OrganicandInorganic
substances.
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15. FUNCTIONS OF AN ECOSYSTEM
Thefunctionofanecosystemisrelatedtothecyclingofmaterials
(matter)andflowofenergy.
Functionsofanecosystemareofthreetypes:
1.PrimaryFunction:Theproducers(plants)canmaketheirfood
themselvesthroughphotosynthesis.Thisprocessiscalledprimary
functionofecosystem.Examples:Allgreenplantsandtrees.
2.SecondaryFunction:Theconsumers(animalsandhumans)cannot
maketheirownfood.Theyarealwaysdependinguponthe
producersfortheirenergy.Thisiscalledsecondaryfunctionofeco
system.
3.TertiaryFunction:Decomposersattackthedeadbodiesofconsumers
andproducersanddecomposethemintosimplercompounds.
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16. •Allows flow of biological energy
ie: control rate of production & respiration of the
community.
•Controls rate of Nutrient cycles
ie: production and consumption of minerals
•Allows circulation of chemical elements along
characteristic path from environment to
organisms and back to environment
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17. Ecological Succession
•Ecosystem passes from a less complex state to
more complex state, which is called as
“ecological succession
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