SlideShare ist ein Scribd-Unternehmen logo
1 von 24
SEMINAR ON PRODUCTION
THEORY



           BY
                NEENU PAUL
PRODUCTION
Production is related to supply of goods &services.
Production is defined as “The creation of utility with
creation or addition of value”.
They are the productive resources
required to produce a given product.these productive resources
     are…….
1)   Raw materials
2)   Services of workers
3)   Capital
4) Organising of work.
Generally the factors of production are
    LAND
    LABOUR
    CAPITAL
DEFNITIONS
 LAWS OF PRODUCTION
Generalization governing relationship between input
  &output.
 PRODUCTION FUNCTION
Relationship between input and output of a firm
 THEORY OF POPULATION
Which govern the supply of labour.
THE BASIC BIOLOGY OF THE
MODEL
The Gordon-schaefer(GS)model considers a single fish
  stock in isolation and is concerned with the way in
  which the stock grows over a time. it is based upon the
  logistic growth model.
Let us suppose that we have an area of sea , we introduce
  a small fish population to it .The growth ,G , of the
  population P over a time period t’ will be a function of
  the initial size of the population ;That is,….
             dp / dt=G=f(P).
 Now the area of sea is relatively small.
 Suppose that to begin with , population growth will be
    roughly proportional to the initial population ; that is,……
   G= Ap .
   The constant a’ is called the intrinsic growth rate.
   Since any given area of sea is ,by definition, limited in size
    ,there must be some maximum size of fish population that
    can be supported . this maximum is usually called the
    environmental carrying capacity(ECC).and is denoted by K.
   As the fish population size approaches the ECC so crowding
    of the sea area will increasingly become a problem.
 The growth rate,G, of the population may then be expected to
  fall,according to the degree of crowding..at any particular
  moment,the growth rate will be propotional to the difference
  between the ECC and the population at the time.this gives us
  the growth equation.
 G=aP[(K-P)/K]
   =aP(1-P/K).
 In the absence of fishing ,the population size will be equal to the
  ECC.
 Differentiating the equation and setting it equal to zero,we must
  see that maximum growth of the fish stock occurs when the
  population size is half of the ECC;that is ,
 G=a(1-2P/K)=0
Hence P=K/2
THE BIOLOGICAL PRODUCTIVITY
CURVE.


Maximum growth
    g
    r
    o
    w
    t
    h


                  k2
       Population size   x
THE EFFECT OF FISHING-The short
run.
 Having consider the unexploited fish stock
 Now introduced fishing
 It is postulated that the yield Y.It depends on two
  factors……..
1. The size of the fish population at the beginning.
2. The amount of fishing effort f’.
          Y=y(P,f).
FISHING EFFORT
 Economists think of effort in terms of the boats, men,
  gear and so on that are required for the fishing activity
  this is usually termed as nominal effort.
 Other word is effective fishing effort. F.
Defined as “the fraction of the average population taken
  by fishing “
 The F is achieved by considering the propotion of the
    stock that survives fishing.
   Precisely ,it is the negative of the natural logarithm of
    the proportion of fish surviving in a year.
               F=qf.
   q=catchability coefficient.
   Clearly if q=1 then f and F are the same thing and the
    analysis of fishing will be the same whichever is used .
 We shall use nominal effort   and our simple short –
  run yield equation becomes
       Y=qfP.
 Here consider the way in which short-run yield will
  change in response to change in effort and population
  size.
POPULATION SIZE
 From eqn Y=qfP the given level of nominal
 effort,yield will vary linearly with population size .the
 greater is the population size,the greater will be the
 yield .
       y
                        sryf3
    Yield                        sryf2

                                   sryf3




                                           x
            production size
DIMINISHING RETERN TO
POPULATION SIZE
Amount of nominal effort is given .
Population size is increases,the given amount of effort
 will be spread more thinly across the population
So ability to catch of the fish to be less .
Here yield may rise less than proportionatly
There for,short-run yield to be a non-linear function of
 population size.
Y=qfP.
SUSTAINABLE YIELD CURVE
                MSY

                 G
                 R
                 O
                 W
                 T
                 H


        ECC/2          EFFORT
    POPULATION
SUSTAINABLE YIELD CURVE
 It is simple quadratic function of effort .
  It is simple mirror image of the biological productivity
  curve .
  It is to notice the difference between the two
        the former is defined with respect to effort .
         the later is respect to population .
  The origin of sustainable yield curve correspond to
  ECC on the biological productivity curve .
SHORT RUN YIELD WITH
DIMINISHING RETURNS TO
NOMINAL EFFORT
Maximum possible short-run catch
                                   population size grown
yield




                                              x

            Nominal effort
THE EFFECT OF FISHING –THE
LONG –RUN.

 Here we must combine our biological production
  function with our yield function.
 G=ap((1-P/K)
 Y=q fβp.
 At the beginning of the second period therefore the
 population size must be ECC-Y.
THE IMPACT OF FISHING ON THE
POPULATION SIZE
 Y



G                Growth curve
R                               SRY
O
W
T
H



                                      X
     POPULATIO             P2   ECC
     N
BIOECONOMIC EQULIBRIUM
 OPEN-ACCESS.
 TOTAL REVENUE EXEEDS TOTAL COST
THE ECONOMICS OF FISHING COST
 TCf=Cf.
 C is the constant.
 Ac ,mc is straight forward
 Acf=MCf=c
    Y                           TCF=CF
   c
   o
   s
   t
                                     ACF=MCF

                       effort        X
FIGURE
   r      Tc f1
 c e
 o v
 s e                       Tc f2
 t n
   u
   e
                     TRf

            effort
  c   r
  o   e
  s   v
  t   e                     AC2=MC2
      n
               MR
      u
      e   effort           AR
Thank you

Weitere ähnliche Inhalte

Ähnlich wie PRODUCTION THEORY by neenu

Bioeconomic analysis of marine fish production in west bengal
Bioeconomic analysis of marine fish production in west bengalBioeconomic analysis of marine fish production in west bengal
Bioeconomic analysis of marine fish production in west bengalAlexander Decker
 
Fish Population Dynamics Lab
Fish Population Dynamics LabFish Population Dynamics Lab
Fish Population Dynamics LabZakiur
 
Consumption Function Assignment of Macroeconomic
Consumption Function Assignment of Macroeconomic  Consumption Function Assignment of Macroeconomic
Consumption Function Assignment of Macroeconomic Muhammad ALI RAZA
 
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docx
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxThe Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docx
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxmehek4
 
The last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum .pdfThe last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum .pdffortmdu
 
efficency of trophic levels
efficency of trophic levelsefficency of trophic levels
efficency of trophic levelsKhaleen
 
Dynamic pool model for Fish stock Assessment,
Dynamic pool model  for Fish stock Assessment,Dynamic pool model  for Fish stock Assessment,
Dynamic pool model for Fish stock Assessment,Ravi Kumar
 
Cohort dynamics and exponential decay model
Cohort dynamics and exponential decay modelCohort dynamics and exponential decay model
Cohort dynamics and exponential decay modelSWAGATIKA SAHOO
 
Recruitment, mortality and exploitation rates estimate and stock assessment o...
Recruitment, mortality and exploitation rates estimate and stock assessment o...Recruitment, mortality and exploitation rates estimate and stock assessment o...
Recruitment, mortality and exploitation rates estimate and stock assessment o...sarmodou
 
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...Alexander Decker
 
Age-Structured Models: Yield-Per-Recruit
Age-Structured Models: Yield-Per-RecruitAge-Structured Models: Yield-Per-Recruit
Age-Structured Models: Yield-Per-RecruitDaniele Baker
 

Ähnlich wie PRODUCTION THEORY by neenu (13)

Bioeconomic analysis of marine fish production in west bengal
Bioeconomic analysis of marine fish production in west bengalBioeconomic analysis of marine fish production in west bengal
Bioeconomic analysis of marine fish production in west bengal
 
Fish Population Dynamics Lab
Fish Population Dynamics LabFish Population Dynamics Lab
Fish Population Dynamics Lab
 
Consumption Function Assignment of Macroeconomic
Consumption Function Assignment of Macroeconomic  Consumption Function Assignment of Macroeconomic
Consumption Function Assignment of Macroeconomic
 
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docx
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docxThe Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docx
The Dynamics of an Open Access FisheryTrond Bjørndal; Jon .docx
 
The last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum .pdfThe last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum .pdf
 
Mathematical modelling of Fish Resources Harvesting with Predator at Maximum ...
Mathematical modelling of Fish Resources Harvesting with Predator at Maximum ...Mathematical modelling of Fish Resources Harvesting with Predator at Maximum ...
Mathematical modelling of Fish Resources Harvesting with Predator at Maximum ...
 
efficency of trophic levels
efficency of trophic levelsefficency of trophic levels
efficency of trophic levels
 
Dynamic pool model for Fish stock Assessment,
Dynamic pool model  for Fish stock Assessment,Dynamic pool model  for Fish stock Assessment,
Dynamic pool model for Fish stock Assessment,
 
Cohort dynamics and exponential decay model
Cohort dynamics and exponential decay modelCohort dynamics and exponential decay model
Cohort dynamics and exponential decay model
 
Recruitment, mortality and exploitation rates estimate and stock assessment o...
Recruitment, mortality and exploitation rates estimate and stock assessment o...Recruitment, mortality and exploitation rates estimate and stock assessment o...
Recruitment, mortality and exploitation rates estimate and stock assessment o...
 
Metapopulation hina
Metapopulation hinaMetapopulation hina
Metapopulation hina
 
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...
11.[62 71]economic efficiency estimate of captured fisheries from plateau sta...
 
Age-Structured Models: Yield-Per-Recruit
Age-Structured Models: Yield-Per-RecruitAge-Structured Models: Yield-Per-Recruit
Age-Structured Models: Yield-Per-Recruit
 

Mehr von DEVIKA ANTHARJANAM (20)

Aquarium
AquariumAquarium
Aquarium
 
ECOSYSTEM BASED FISHERIES MANEGEMNT
ECOSYSTEM BASED FISHERIES MANEGEMNTECOSYSTEM BASED FISHERIES MANEGEMNT
ECOSYSTEM BASED FISHERIES MANEGEMNT
 
CODE OF CONDUCT FOR RESPONSIBLE FISHERIES
CODE OF CONDUCT FOR RESPONSIBLE FISHERIESCODE OF CONDUCT FOR RESPONSIBLE FISHERIES
CODE OF CONDUCT FOR RESPONSIBLE FISHERIES
 
Nimnaga. ecnmcs. territorial use rights 4th sem
Nimnaga. ecnmcs. territorial use rights 4th semNimnaga. ecnmcs. territorial use rights 4th sem
Nimnaga. ecnmcs. territorial use rights 4th sem
 
Neenu self presentation
Neenu self presentationNeenu self presentation
Neenu self presentation
 
Naveen
NaveenNaveen
Naveen
 
Mgmt organisations reshmiii
Mgmt organisations  reshmiiiMgmt organisations  reshmiii
Mgmt organisations reshmiii
 
Law of th sea ali
Law of th sea aliLaw of th sea ali
Law of th sea ali
 
INDIVIDUAL TRANSFERABLE QUATA SYSTEM
INDIVIDUAL TRANSFERABLE QUATA SYSTEMINDIVIDUAL TRANSFERABLE QUATA SYSTEM
INDIVIDUAL TRANSFERABLE QUATA SYSTEM
 
Integrated fisheries management i
Integrated fisheries management iIntegrated fisheries management i
Integrated fisheries management i
 
Abhinav semenar of thoma
Abhinav semenar of thomaAbhinav semenar of thoma
Abhinav semenar of thoma
 
Suraj 3 water act
Suraj 3  water actSuraj 3  water act
Suraj 3 water act
 
Suraj 2 environmental protection act-1986
Suraj 2  environmental protection act-1986Suraj 2  environmental protection act-1986
Suraj 2 environmental protection act-1986
 
Suraj 1 coastal zone notification 1991
Suraj 1 coastal zone notification 1991Suraj 1 coastal zone notification 1991
Suraj 1 coastal zone notification 1991
 
CO MANAGEMENT IN FISHERIES
CO MANAGEMENT IN FISHERIESCO MANAGEMENT IN FISHERIES
CO MANAGEMENT IN FISHERIES
 
Management of indian fisheries
Management of indian fisheriesManagement of indian fisheries
Management of indian fisheries
 
James
JamesJames
James
 
Hitha
HithaHitha
Hitha
 
3...man and mechine
3...man and mechine3...man and mechine
3...man and mechine
 
3...maintenance management
3...maintenance management3...maintenance management
3...maintenance management
 

Kürzlich hochgeladen

Scanning the Internet for External Cloud Exposures via SSL Certs
Scanning the Internet for External Cloud Exposures via SSL CertsScanning the Internet for External Cloud Exposures via SSL Certs
Scanning the Internet for External Cloud Exposures via SSL CertsRizwan Syed
 
Training state-of-the-art general text embedding
Training state-of-the-art general text embeddingTraining state-of-the-art general text embedding
Training state-of-the-art general text embeddingZilliz
 
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek SchlawackFwdays
 
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024BookNet Canada
 
DevoxxFR 2024 Reproducible Builds with Apache Maven
DevoxxFR 2024 Reproducible Builds with Apache MavenDevoxxFR 2024 Reproducible Builds with Apache Maven
DevoxxFR 2024 Reproducible Builds with Apache MavenHervé Boutemy
 
"ML in Production",Oleksandr Bagan
"ML in Production",Oleksandr Bagan"ML in Production",Oleksandr Bagan
"ML in Production",Oleksandr BaganFwdays
 
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)Mark Simos
 
Search Engine Optimization SEO PDF for 2024.pdf
Search Engine Optimization SEO PDF for 2024.pdfSearch Engine Optimization SEO PDF for 2024.pdf
Search Engine Optimization SEO PDF for 2024.pdfRankYa
 
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024BookNet Canada
 
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage Cost
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage CostLeverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage Cost
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage CostZilliz
 
Artificial intelligence in cctv survelliance.pptx
Artificial intelligence in cctv survelliance.pptxArtificial intelligence in cctv survelliance.pptx
Artificial intelligence in cctv survelliance.pptxhariprasad279825
 
Are Multi-Cloud and Serverless Good or Bad?
Are Multi-Cloud and Serverless Good or Bad?Are Multi-Cloud and Serverless Good or Bad?
Are Multi-Cloud and Serverless Good or Bad?Mattias Andersson
 
Story boards and shot lists for my a level piece
Story boards and shot lists for my a level pieceStory boards and shot lists for my a level piece
Story boards and shot lists for my a level piececharlottematthew16
 
Install Stable Diffusion in windows machine
Install Stable Diffusion in windows machineInstall Stable Diffusion in windows machine
Install Stable Diffusion in windows machinePadma Pradeep
 
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmatics
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmaticsKotlin Multiplatform & Compose Multiplatform - Starter kit for pragmatics
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmaticscarlostorres15106
 
My INSURER PTE LTD - Insurtech Innovation Award 2024
My INSURER PTE LTD - Insurtech Innovation Award 2024My INSURER PTE LTD - Insurtech Innovation Award 2024
My INSURER PTE LTD - Insurtech Innovation Award 2024The Digital Insurer
 
AI as an Interface for Commercial Buildings
AI as an Interface for Commercial BuildingsAI as an Interface for Commercial Buildings
AI as an Interface for Commercial BuildingsMemoori
 
My Hashitalk Indonesia April 2024 Presentation
My Hashitalk Indonesia April 2024 PresentationMy Hashitalk Indonesia April 2024 Presentation
My Hashitalk Indonesia April 2024 PresentationRidwan Fadjar
 
Connect Wave/ connectwave Pitch Deck Presentation
Connect Wave/ connectwave Pitch Deck PresentationConnect Wave/ connectwave Pitch Deck Presentation
Connect Wave/ connectwave Pitch Deck PresentationSlibray Presentation
 

Kürzlich hochgeladen (20)

Scanning the Internet for External Cloud Exposures via SSL Certs
Scanning the Internet for External Cloud Exposures via SSL CertsScanning the Internet for External Cloud Exposures via SSL Certs
Scanning the Internet for External Cloud Exposures via SSL Certs
 
Training state-of-the-art general text embedding
Training state-of-the-art general text embeddingTraining state-of-the-art general text embedding
Training state-of-the-art general text embedding
 
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
"Subclassing and Composition – A Pythonic Tour of Trade-Offs", Hynek Schlawack
 
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
 
DevoxxFR 2024 Reproducible Builds with Apache Maven
DevoxxFR 2024 Reproducible Builds with Apache MavenDevoxxFR 2024 Reproducible Builds with Apache Maven
DevoxxFR 2024 Reproducible Builds with Apache Maven
 
"ML in Production",Oleksandr Bagan
"ML in Production",Oleksandr Bagan"ML in Production",Oleksandr Bagan
"ML in Production",Oleksandr Bagan
 
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)
Tampa BSides - Chef's Tour of Microsoft Security Adoption Framework (SAF)
 
Search Engine Optimization SEO PDF for 2024.pdf
Search Engine Optimization SEO PDF for 2024.pdfSearch Engine Optimization SEO PDF for 2024.pdf
Search Engine Optimization SEO PDF for 2024.pdf
 
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
Transcript: New from BookNet Canada for 2024: BNC CataList - Tech Forum 2024
 
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage Cost
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage CostLeverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage Cost
Leverage Zilliz Serverless - Up to 50X Saving for Your Vector Storage Cost
 
Artificial intelligence in cctv survelliance.pptx
Artificial intelligence in cctv survelliance.pptxArtificial intelligence in cctv survelliance.pptx
Artificial intelligence in cctv survelliance.pptx
 
Are Multi-Cloud and Serverless Good or Bad?
Are Multi-Cloud and Serverless Good or Bad?Are Multi-Cloud and Serverless Good or Bad?
Are Multi-Cloud and Serverless Good or Bad?
 
Story boards and shot lists for my a level piece
Story boards and shot lists for my a level pieceStory boards and shot lists for my a level piece
Story boards and shot lists for my a level piece
 
Install Stable Diffusion in windows machine
Install Stable Diffusion in windows machineInstall Stable Diffusion in windows machine
Install Stable Diffusion in windows machine
 
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmatics
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmaticsKotlin Multiplatform & Compose Multiplatform - Starter kit for pragmatics
Kotlin Multiplatform & Compose Multiplatform - Starter kit for pragmatics
 
My INSURER PTE LTD - Insurtech Innovation Award 2024
My INSURER PTE LTD - Insurtech Innovation Award 2024My INSURER PTE LTD - Insurtech Innovation Award 2024
My INSURER PTE LTD - Insurtech Innovation Award 2024
 
DMCC Future of Trade Web3 - Special Edition
DMCC Future of Trade Web3 - Special EditionDMCC Future of Trade Web3 - Special Edition
DMCC Future of Trade Web3 - Special Edition
 
AI as an Interface for Commercial Buildings
AI as an Interface for Commercial BuildingsAI as an Interface for Commercial Buildings
AI as an Interface for Commercial Buildings
 
My Hashitalk Indonesia April 2024 Presentation
My Hashitalk Indonesia April 2024 PresentationMy Hashitalk Indonesia April 2024 Presentation
My Hashitalk Indonesia April 2024 Presentation
 
Connect Wave/ connectwave Pitch Deck Presentation
Connect Wave/ connectwave Pitch Deck PresentationConnect Wave/ connectwave Pitch Deck Presentation
Connect Wave/ connectwave Pitch Deck Presentation
 

PRODUCTION THEORY by neenu

  • 2. PRODUCTION Production is related to supply of goods &services. Production is defined as “The creation of utility with creation or addition of value”.
  • 3. They are the productive resources required to produce a given product.these productive resources are……. 1) Raw materials 2) Services of workers 3) Capital 4) Organising of work. Generally the factors of production are  LAND  LABOUR  CAPITAL
  • 4. DEFNITIONS  LAWS OF PRODUCTION Generalization governing relationship between input &output.  PRODUCTION FUNCTION Relationship between input and output of a firm  THEORY OF POPULATION Which govern the supply of labour.
  • 5. THE BASIC BIOLOGY OF THE MODEL The Gordon-schaefer(GS)model considers a single fish stock in isolation and is concerned with the way in which the stock grows over a time. it is based upon the logistic growth model. Let us suppose that we have an area of sea , we introduce a small fish population to it .The growth ,G , of the population P over a time period t’ will be a function of the initial size of the population ;That is,…. dp / dt=G=f(P).
  • 6.  Now the area of sea is relatively small.  Suppose that to begin with , population growth will be roughly proportional to the initial population ; that is,……  G= Ap .  The constant a’ is called the intrinsic growth rate.  Since any given area of sea is ,by definition, limited in size ,there must be some maximum size of fish population that can be supported . this maximum is usually called the environmental carrying capacity(ECC).and is denoted by K.  As the fish population size approaches the ECC so crowding of the sea area will increasingly become a problem.
  • 7.  The growth rate,G, of the population may then be expected to fall,according to the degree of crowding..at any particular moment,the growth rate will be propotional to the difference between the ECC and the population at the time.this gives us the growth equation.  G=aP[(K-P)/K] =aP(1-P/K).  In the absence of fishing ,the population size will be equal to the ECC.  Differentiating the equation and setting it equal to zero,we must see that maximum growth of the fish stock occurs when the population size is half of the ECC;that is ,  G=a(1-2P/K)=0 Hence P=K/2
  • 8. THE BIOLOGICAL PRODUCTIVITY CURVE. Maximum growth g r o w t h k2  Population size x
  • 9. THE EFFECT OF FISHING-The short run.  Having consider the unexploited fish stock  Now introduced fishing  It is postulated that the yield Y.It depends on two factors…….. 1. The size of the fish population at the beginning. 2. The amount of fishing effort f’. Y=y(P,f).
  • 10. FISHING EFFORT  Economists think of effort in terms of the boats, men, gear and so on that are required for the fishing activity this is usually termed as nominal effort.  Other word is effective fishing effort. F. Defined as “the fraction of the average population taken by fishing “
  • 11.  The F is achieved by considering the propotion of the stock that survives fishing.  Precisely ,it is the negative of the natural logarithm of the proportion of fish surviving in a year.  F=qf.  q=catchability coefficient.  Clearly if q=1 then f and F are the same thing and the analysis of fishing will be the same whichever is used .
  • 12.  We shall use nominal effort and our simple short – run yield equation becomes  Y=qfP.  Here consider the way in which short-run yield will change in response to change in effort and population size.
  • 13. POPULATION SIZE  From eqn Y=qfP the given level of nominal effort,yield will vary linearly with population size .the greater is the population size,the greater will be the yield .
  • 14. y  sryf3 Yield sryf2 sryf3 x production size
  • 15. DIMINISHING RETERN TO POPULATION SIZE Amount of nominal effort is given . Population size is increases,the given amount of effort will be spread more thinly across the population So ability to catch of the fish to be less . Here yield may rise less than proportionatly There for,short-run yield to be a non-linear function of population size. Y=qfP.
  • 16. SUSTAINABLE YIELD CURVE  MSY G R O W T H ECC/2 EFFORT POPULATION
  • 17. SUSTAINABLE YIELD CURVE  It is simple quadratic function of effort . It is simple mirror image of the biological productivity curve . It is to notice the difference between the two the former is defined with respect to effort . the later is respect to population . The origin of sustainable yield curve correspond to ECC on the biological productivity curve .
  • 18. SHORT RUN YIELD WITH DIMINISHING RETURNS TO NOMINAL EFFORT Maximum possible short-run catch population size grown yield x Nominal effort
  • 19. THE EFFECT OF FISHING –THE LONG –RUN.  Here we must combine our biological production function with our yield function.  G=ap((1-P/K)  Y=q fβp.  At the beginning of the second period therefore the population size must be ECC-Y.
  • 20. THE IMPACT OF FISHING ON THE POPULATION SIZE Y G Growth curve R SRY O W T H X POPULATIO P2 ECC N
  • 21. BIOECONOMIC EQULIBRIUM  OPEN-ACCESS.  TOTAL REVENUE EXEEDS TOTAL COST
  • 22. THE ECONOMICS OF FISHING COST  TCf=Cf.  C is the constant.  Ac ,mc is straight forward  Acf=MCf=c Y TCF=CF c o s t ACF=MCF effort X
  • 23. FIGURE r Tc f1 c e o v s e Tc f2 t n u e TRf effort c r o e s v t e AC2=MC2 n MR u e effort AR