IAICI - aspects methodo.key - Frédéric AMBLARD

Simulation aim: «show» and share the model of the reference system dynamic. ... Source: Can Tho, How to Grow ?, Vera Konings, .... Data collecron, cleaning and management are a huge and hard work in .... Toolbox for agent-‐based modeling in Java, numerous libraries of ... https://code.google.com/p/gama-‐platform/.
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Methodological  aspects  of     agent-­‐based  modeling  and   simula5on  of  complex  systems ! !

Benoit  Gaudou

step 1: define the modeling questions

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 4: define the agents (characteristics, dynamics)

UMR  5505  IRIT,  CNRS  /  Université  de  Toulouse  -­‐  benoit.gaudou@ut-­‐capitole.fr

1

«A  model  is  a  simplified  representa5on  of  a  reference  system  that   helps  to  answer  a  ques5on  on  this  system.»  [Drogoul]

A map is a static model. Here of urban area of Can Tho (Vietnam) in 2010. [Konings,  2012] [Can  Tho  on  google  maps]

Meteorologic dynamic models allow to predict a typhoon evolution over 48h. Neoguri   t yphoon,   J uly   2 014 http://lesbrindherbes.org/2014/07/06/l-enorme-typhon-neoguri-se-dirige-japon/

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A  simula5on  is  an  execu5on  of  a  computer  dynamic  model.

Simulation  can  be  used  for:      Validation,  Evaluation,  Verification   Simulation  aim:  test  or  verify  an  hypothesis  on  the  reference  system;  validate  a  theory.   !  Understanding,  Exploration
 Simulation  aim:  rebuild  the  system  to  understand  it,  producing  an  object  that  we  can   experiment   !  Communication,  Training,  Visualization  
 Simulation  aim:  «show»  and  share  the  model  of  the  reference  system  dynamic.   !  Control,  Action,  Decision-­‐Support  System  
 Simulation  aim:  simulation  as  Decision-­‐Support  System  to  a  policy  or  actors’  decisions   (that  could  be  assessed  on  the  simulation)   !  Prevision,  Prediction,  Anticipation  
 Simulation  aim:  predict  possible  evolutions  of  the  reference  system,  given  specific   Alexis Drogoul perturbations.

3

Three  model  examples  will  be  presented  today. Understanding  and  exploring  urban   spatial  dynamics   Case  study:  Can  Tho  (Vietnam)  

!

Assessment  of  the  social,  economic   and  environmental  impacts  of  the   various  alternative  of  definition  and   management  of  (new)  water  Volume   Available  for  Agriculture?   Case  study:  Adour-­‐Garonne  basin  (France)  

!

Reproducing  and  exploring  past  events   using  agent-­‐based  geo-­‐historical   models   Case  study:  floods  of  1926,  Hanoi  (Vietnam)   !

  4

Current  changes  in  worldwide  urbaniza5on  paFerns  at  all  geographic   scales  are  quite  likely  the  most  significant  since  the  advent  of  humanity !

Coloniza5on  of  remote  rural  and  wild-­‐land  spaces;     !

Emergence  of  new  types  of  urban  specializa5ons  (e.g.,  technopoles);       Increasing  spa5al  segrega5on  of  social  groups;     !

Spa5al  fragmenta5on  of  labor  markets;     !

Increasing  threats  from  natural  hazards  as  urban  structures  become  more  dispersed,   resource-­‐demanding  and  complex;     !

Exposure  to  new  kinds  of  vulnerabili5es  given  their  increasing  dependence  on   technology;  

Slide by Alexis Drogoul

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To  address  the  challenges  raised  by  these  changes,  there  is  a  need  for   tools  and  models  that  can  support  deciders  in: !

Providing  knowledge  on  and  understanding   the  dynamics  of  the  urban  system,   An5cipa5ng  and  forecas5ng  future  changes   or  trends  of  development,   Describing  and  assessing  impacts  of  future   development,   Exploring  different  policies  and  op5mizing   planning  and  management  of  sustainable   urban  areas.   !

Focus  on  designing  and  exploiDng  urban  morphogenesis  (or  growth)   models,  i.e.  models  that  represent  the  evoluDon(s)  of  the  spaDal   inscripDon  of  the  city.   Slide by Alexis Drogoul

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The  data  requirements  for  designing  urban  models  are  intense  due  to   the  complexity  of  their  object  and  the  variety  of  their  objec5ves

Satellite  &  aerial  images  -­‐  Surveys  -­‐  Census  -­‐  Field  studies  -­‐  Sociological  studies  

Topography,  hydrography   Economical  data  

Slide by Alexis Drogoul

Transport  infrastructures  

Environmental  data  

Social  data  

Land  cover,  land  use  data  

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Example:  Can  Tho  city  (Vietnamese  Mekong  Delta)

Slide by Alexis Drogoul

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Why  Can  Tho  ? It  is  the  largest  and  fastest  growing  city   in  the  Mekong  Delta.     Its  evoluDon  underlines  a  number  of   the  challenges  raised  by  urban  growth.   A  comprehensive  dataset  on  the   evoluDon  of  the  city  shape  has  been   gathered  and  built  by  researchers  and   pracDDoners.  

Existing settlem

Strategic locatio

! s

!

 

1750

1950

2010 Can Tho,

Source: Can Tho, How to Grow ?,Vera Konings,

Master thesis, 28th June 2012, Univ. of Delft, the Netherlands

Slide by Alexis Drogoul

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Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model Cycle proposed by Patrick Taillandier

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

«Every  model  has  to  start  from  a  clear  ques5on,  problem,  or   hypothesis.»  [Grimm,  et  al.  2010]

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

Which  ques5ons  for  which  models  ? Among  dynamic  models  we  can  distinguish:      -­‐  Reproduction  models:  that  try,  given  data,  to  reproduce  as  precisely  as  possible   these  data  by  simulation.     -­‐-­‐-­‐>  we  cannot  understand  the  way  the  phenomenon  is  generated.
 But  it  could  «predict  the  future»,  e.g.  weather  forecast.   !

 -­‐  Understanding  models:  that  try  to  understand  processes  that  generate   phenomena.  They  are  focused  on  the  processes  and  try  to  get  the  phenomenon   by  simulation.   -­‐-­‐-­‐>  allow  to  understand,  explain  and  generate  the  phenomenon.            Consequence:  we  can  «  ask  questions  to  the  model»  via  What-­‐If  scenario.   !

We  cannot  tackle  the  same  questions  with  all  kinds  of  models.  

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We  focus  on  a  par5cular  phenomenon:  the  urban  growth  of  Can  Tho.

[Konings,  2012]

We  have  chosen  to  build  an  understanding  model:      -­‐  we  will  look  at  mechanisms  able  to  reproduce  the   urban  growth   !

A  reason  is  the  possibility  to  do  urban  planning   prospection  using  this  kind  of  models.

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Examples  of  ques5ons  that  can  be  asked  to  the  Can  Tho  urban  model   growth. ! !

Influence  of  the  transport  network  on  urban  growth:   Construction  or  destruction  of  a  road   Improvement  of  the  transport  network  (e.g.  larger  roads...  )   Influence  of  the  network  on  the  ratio  residential,  services  buildings.   !

Influence  of  the  building  of  a  shopping  center,  or  other  services.   !

Influence  of  the  urban  growth  on  the  traffic  and  on  public  transport.   !

What  services  (hospital,  school,  water  network...)  are  needed  to  add  taking   into  account  urban  growth  ?

14

Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

There  is  a  huge  number  of  languages  to  write  a  dynamic  model.   Consider  2  main  approaches:        -­‐  equation-­‐based  models:  describe  the   evolution  at  macroscopic  level   !

   -­‐  agent-­‐based  models:  describe   microscopic  entities,  their  behaviors   and  interactions  between  these   entities  and  generate  a  macroscopic   behavior  

LWR  macroscopic  model

NaSch microscopic model

!

Example:  traffic   !

We  focus  on  agent-­‐based   model  here. Example of epidemic equation-based model 16

Example:  macro-­‐simula5on  model  of  traffic

Based  on  an  analogy  between  the  traffic  flow  and  the  fluid  flow  in  a   pipe.

The  vehicle  flow  is  characterized  by  macroscopic  attributes.   Individual  behaviors  are  averaged  in  a  global  equation.

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Example:  agent-­‐based  simula5on  model  of  traffic

Behaviors  (rules)  are  associated  to  individual  vehicles.

Allows  a  variety  of  behaviors  and  stochasticity.   Analytical  results  "impossible"  to  get:  obligation  to  go  through  the  simulation.

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En55es  and  dynamics

!

«An  entity  is  a  distinct,  separate  object  or  actor  that   behaves  as  a  unit  and  may  interact  with  other  entities  or   be  affected  by  external  environmental  factors.  »    

Ferber 89

!

«Its  current  state  is  characterized  by  its  state  variables  or   attributes.  »   !

Processes/dynamics  are  change  factors  in  the  system.  They   can  be  performed  by  the  entities  or  have  an   environmental  source  (e.g.  weather  ...  )   ! ! !

Definition  by  [Grimm  et  al,  2010] 19

Model  1:  en55es,  dynamic  and  scales •Spatial  scale   •Area  that  covers  Can  Tho  city  and  the  nearby  suburbs   !

•Time  scale   •Duration  :  15  years  from  1999  to  2014  

MeKong Delta

! !

70 km

•Entities  to  take  into  account   •Buildings   •Roads   •Rivers  

!

•Dynamic  to  take  into  account   •The  construction  of  buildings

45 km

Considered area

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Model  2:  en55es,  dynamic  and  scales •Spatial  scale   •The  An  Binh  ward  of  Can  Tho   !

•Time  scale   •Duration  :  5  years  from  2005  to  2010   ! ! !

Can Tho 3 km

•Entities  to  take  into  account   •Buildings   •Roads   •Rivers  

!

•Dynamic  to  take  into  account  

3 km

•The  construction  of  buildings Considered area

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Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

Data  collec5on,  cleaning  and  management  are  a  huge  and  hard  work  in   a  modeling  and  simula5on  project! First:  Get  data    -­‐  collect  yourself,      -­‐  ask/buy  from  government  agency,   -­‐  get  open  source  data  (Open  Data),  e.g.   OpenStreetMap,  IGN  (France)              -­‐>  unequal  quality    

co-­‐evolution  in  the  MAELIA   Project  between  question/data/ representation


Data

Data’

Data’’

!

E.g.  :  to  get  data  from  Can  Tho,  we  need  to   ask  the  Department  for  Natural   Ressources  and  Environment  (Sở  tài   nguyên  môi  trường  Cần  Thơ)  

Representation

Representation’

Stable Representation

Question’

Question’’

!

E.g.  :  in  France,  IGN,  INSEE,  Water   Agency...


Initial question

Then:  process  and  clean  them.   23

Data  need  to  be  cleaned  and  processed,  depending  on  the  aim  and   need  of  the  model. Aim:  building  of  a  common  GIS  merging   data  from  all  the  various  sources.   !

Example  on  the  MAELIA  project   of  data  integration.


Example  of  issues  to  tackle:      -­‐  convert  all  the  data  formats  in  a   common  one        -­‐  clean  data  (e.g.  correct  invalid   polygons,  overlapping  or  disjoints   polygons...)      -­‐  transform  data  to  be  used  in  the  model   (e.g.  ,  switch  from  polygons  to   polylines  for  roads...)      -­‐  correct/create  attribute  table  for  each   geographic  objects      -­‐  integrate  /  cross  various  data  sources   24

Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

Given  the  chosen  en55es  and  the  data  collected,  we  have  to  choose   what  will  be  an  agent  in  our  model  (i.e.  an  en5ty  with  a  behavior) What  will  be  an  agent  depends  mainly  on   the  chosen  scale  (and  data  &  question).      -­‐  If  we  want  to  simulate  a  city,  do  we  need   to  take  into  account  each  inhabitant,  each   household,  each  building  ...  ?  

Can Tho - Ninh Kieu - 2010

!

First  attempt:          -­‐  as  we  are  interested  in  the  new  buildings,   we  can  chose  to  make  buildings  as  agents.        -­‐  They  have  a  shape,  location  and  type  as   attributes.   !

We  have  concrete  agents:  
 1  agent  =  1  physical  entity   !

Dynamics  should  then  be  described  at  the   level  of  the  building.

! This  choice  leads  to  a  vector  model 26

Given  the  chosen  en55es  and  the  data  collected,  we  have  to  choose   what  will  be  an  agent  in  our  model  (i.e.  an  en5ty  with  a  behavior) The  previous  choice  is  relevant  to  work  at   the  district  scale  (not  a  too  high  number   of  buildings).   To  deal  with  the  whole  city,  we  have  to   switch  to  something  else...  

Can Tho 1999

!

Second  attempt:          -­‐  we  choose  to  discretize  to  whole  space   on  a  regular  grid.  Agents  will  be  the  cells.              -­‐  they  are  characterized  by  a  rate  of   building  on  the  cell  area.   !

We  have  abstract  agents:  
 1  agent  =  1  entity  aggregating  buildings.   !

We  can  choose  the  number  of  cells,  so  the   discretization  rate,  and  so  the  precision.

! This  choice  leads  to  a  raster  model.   27

The  UML  language  is  commonly  used  as  a  modeling  tool  to  describe   the  kinds  of  agents,  their  aFributes  and  opera5ons. UML  is  a  graphical  language  allowing  to  specify,  visualize,  build  and  document   elements  of  a  system  or  a  model.   !

We  focus  only  on  class  diagrams  =  the  part  of  UML  allowing  us  to  represent  the   types  of  agents  (species),  their  attributes  and  relations  between  these  types.   !

Example  from  the  raster  model:  for  agents  cell,  with  it  set  of  attributes       !

Name  of  species attributes

operations   28

Determina5on  of  the  processes  that  can  generate  the  phenomenon.   Introduc5on  example. Which  processes/rules  an  we  introduce  to  reproduce  the  phenomenon  ?   !

E.g.  :  What  will  be  x?  and  y?  ?  

1

2

3

5

8

13

x?

y?

29

Determina5on  of  the  processes  that  can  generate  the  phenomenon. Introduc5on  example. Which  processes/rules  an  we  introduce  to  !reproduce  the  phenomenon  ?   !

!

E.g.  :  What  will  be  x?  and  y?  ?    

!

!

!

!

!

!

!

! !

1

2

3

5

!

8

13

x?

y?

!

By  observing  the  number  series,  we  can  observe   ! a  regularity:      -­‐  3  =  1  +  2   !  -­‐  5  =  2  +  3   !  -­‐  8  =  3  +  5   So  we  can  predict  next  values:      -­‐  13  =  5  +  8  -­‐  x?  =  8  +  13  =  21    -­‐  y?  =  13  +  x?  =  13  +21  =  34      

30

     Similarly,     to  generate  the  urban  growth,  you  can  look  at  this  picture   and  propose  rule(s)  to  locate  the  next  buildings...

[Konings,  2012]

31

Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

Models  can  be  implemented  and  simulated  using  any  generic   programming  language,  but  also  with  some  dedicated  (open-­‐source)   pla]orms. ! NetLogo     http://ccl.northwestern.edu/netlogo/   Pedagogical  tool  with  a  specific  modeling  language.  Numerous   examples  in  various  domains.  Ideal  for  beginners  and   prototypes,  but  somehow  limited  for  large  models.  

! ! Repast  Simphony   http://repast.sourceforge.net/   Toolbox  for  agent-­‐based  modeling  in  Java,  numerous  libraries  of   connected  technologies  (statistical  analysis,  GIS,  3D  models,   etc.).  Very  powerful  but  requires  very  good  programming  skills.  

! ! GAMA   http://gama-­‐platform.googlecode.com   A  compromise  between  the  two  platforms  above.  Using  a   dedicated  modeling  language,  this  platform  pays  a  great  deal  of   attention  to  the  modeling  of  the  environment  and  the  use  of  GIS   data,  while  staying  open  to  new  technologies  through  plug-­‐ins.  

33

Highlight  on  the  GAMA  pla]orm

   

 for  its  management  of  GIS  data  

for  its  user-­‐friendly  and   powerful  IDE   !  for  its  modeling  language  

https://code.google.com/p/gama-­‐platform/

34

Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

A  model  is  an  object  that  can  be  manipulated  or  explored  via   simula5on  and  on  which  we  can  launch  experiments. Parameters

w1

between 0 and 1 w2

between 0 and 1 w3

between 0 and 1

Outputs

Experiments

Model Inputs

Data

36

O`en  there  are  at  least  2  ways  to  run  simula5ons.  

! !

GUI  experiment:   Gui  experiments  allow  the  modeler  to  observe  indicators  evolution   during  a  simulation   !

batch  experiment:   batch  experiments  allow  model  to  observe  the  evolution  of   indicators  of  the  simulation  (computed  at  the  end  of  the   simulation)  over  the  change  of  parameters.  

37

GUI  experiments  allow  to  test  various  parameters  values  and  observe   the  output....  which  can  be  long  and  fas5dious  at  hand  ... w1 = 0.2

w2 = 0.0

w3 = 1.0

Experiments

Error = 0.2869

w1 = 0.7

w2 = 0.5

w3 = 0.2

Experiments

w1 = 0.5

w2 = 0.3

w3 = 0.8

Experiments

Error = 0.5093

Error = 0.4344

......

38

The  batch  mode  allows  to  automatically  execute  parameter  space   exploration.

Exploring  the  parameters  space  of  a  model  can  be  used   to:   •

Correct  the  model,  



Do  sensibility  analysis,  



Calibrate  it,  



Discover  emerging  properties,  



…  

A  necessary  step!

Explore  the  model  behavior  through  the  explora5on  of  the  parameters   space. Aim:  to  have  a  deep  knowledge  of  the   behavior  of  the  model  (and  in  particular   its  sensitivity  to  parameters  variations)   ==>  the  range  of  values  to  which  the   simulation  is  very  sensitive  -­‐>   discretization  need  (step=  1,  0.1  or   0.0001  ...)  

Mean size of aggregates depending on the 2 parameters:

- number of different neighbors accepted

- population density

(Daudé E. & Langlois P. 2006)

!

Example  on  the  Schelling’s  model:   !

Population

density

! ! ! ! !

Number of different neighbors that can be accepted by an agent

«Exhaustive» exploration of the Schelling’s model 40

The  calibra5on  allows  to  find  parameters  values  making  the  simula5on   results  fiang  to  real  data. Objective:     What  are  the  values  of  parameters:  
 -­‐  that  allow  to  obtain  a  «realist»  model  ?
 -­‐  that  minimize  the  difference  between   real  and  simulated  data  ? Real data (at the time of the simulation end) error  =  difference   between  simulated   data  and  real  data parameter1 = ??

p2 = ??

p3 = ??

Real data at initial time

Experim

Simulated data at the end of the simulation

41

Issues  linked  to  the  calibra5on. Find  a  good  indicator  (often  named   fitness)  to  represent  the  fact  that  a   simulation  is  «good»  (e.g.  the   difference  between  real  and  simulated   data):          -­‐  in  the  case  of  urban  growth  model,   this  indicator  should  represent  the   distance  between  real  and  simulated   maps.  

Population

density

Number of different neighbors that can be accepted by an agent

!

To  find  the  parameters  is  closed  to  an   optimization  problem  (minimize  a   value):            -­‐  lot  of  methods  exist  (exhaustive,   Genetic  algorithms,  ...  )            

http://nickmalleson.co.uk/wp-content/uploads/2013/04/parameter_space.png

42

Once  the  model  has  been  calibrated,  we  can  explore  the  result  of  the   simula5on  to  various  scenario. We  can  define  scenario  that  we  want  to  explore:    -­‐  building  of  a  new  road,  of  new  houses,  services...  

What-If water channels

are improved ?

?????????? 43

Steps  in  an  experiment  design.

General  method  :   •

Define  an  initial  situation  and  a  stop  criterion  (of  1   simulation)  



Select  the  set  of  parameters  to  explore  and  the  indicators  



Define  a  strategy  of  exploration    



Execute,  collect  and  save  the  data  



Analyze  the  collected  data

Can  Tho  Case  study • Objective:  reproduce  the  urban  growth   of  the  agglomeration  of  Can  Tho  from   1999  to  2014 Empty space Water space Built space Road City center Can Tho 1999

For  each  free  cell  (empty  space):  evaluation  of   their  constructability  value  based  on  3   indicators:  
 -­‐  density  (C1):   ! -­‐  distance  to  road  (C2):   ! -­‐  distance  to  city  center  (C3):  

45

Can  Tho  Case  study:  first  simula5on  with  only  the  distance  to  road   criterion

Construction along the roads 46

Can  Tho  Case  study:  first  simula5on  with  only  the  distance  to  city   center  criterion

Expansion of the city center 47

Can  Tho  Case  study:  first  simula5on  with  only  the  (low)  density   criterion

Lot of small «building blocks» covering uniformly the space C1 : density = 1 - (number of built neighbor cells / number of neighbor cells)

48

Can  Tho  Case  study:  first  simula5on  with  only  the  (high)  density   criterion

Expansion from high density areas C1 : density = (number of built neighbor cells / number of neighbor cells)

49

Can  Tho  Case  study:  calibra5on  of  the  model  to  reproduce  the  real   urban  growth

Empty space Water space Built space Road

How to evaluate the error between the simulation and the observed data?

Use of the Fuzzy Kappa Sim indicator 50

Modeling  is  a  mul5-­‐step  cycle.

step 1: define the modeling questions

step 7: explore the model

step 2: identify the elements (entities, dynamics) to model step 3: collect data

step 6: calibrate the model

step 4: define the agents (characteristics, dynamics)

step 5: implement the model

We  can  also  use  the  model  to  assess  What-­‐If?  scenario  on  the  model.

! !

From  an  initial  state

What-If no change is done

in terms of urban planning ?

??????????

Modeling  can  be  useful:   -­‐  to  build  Decision-­‐ Support  Systems  (DSS)   -­‐>  to  help  urban  planning. [Konings,  2012]

What-If water channels

are improved ?

??????????

52

References [Konings,  2012]  Konings  V.,  «  Can  Tho,  how  to  grow?  Flood  proof  expansion  in   rapidly  urbanising  delta  cities  in  the  Mekong  delta:  the  case  of  Can  Tho.»,  Master   thesis,  University  of  Delft,  2012.
 http://repository.tudelft.nl/view/ir/uuid%3A84c58546-­‐e387-­‐44f7-­‐b8ff-­‐0958b018ae83/   !

[Grimm  et  al.,  2010]  Volker  Grimm,  Uta  Berger,  Donald  L.  DeAngelis,  J.  Gary  Polhill,   Jarl  Giske,  Steven  F.  Railsback.  «The  ODD  protocol:  A  review  and  first  update»,   Ecological  Modelling  221,  2760–2768,  2010.

53

References:  Web   Some  websites:   ! JASSS  :  Journal  of  Artificial  Societies  and  Social  Simulation   http://jasss.soc.surrey.ac.uk/  

! ACE  :  Agent-­‐based  Computational  Economics   http://www.econ.iastate.edu/tesfatsi/ace.htm  

! GisAgents  :  GIS  and  Agent-­‐Based  Modelling   http://www.gisagents.blogspot.com/  

! OpenABM:  Open  Agent-­‐Based  Modeling  Consortium   http://www.openabm.org/  

!

Slide by Alexis Drogoul

54

References:  some  books Four  books:   ! GILBERT  N  and  TROITZSCH  K.  G.  (2005)   Simulation  for  the  Social  Scientist.  Milton   Keynes:  Open  University  Press,  Second   Edition.   GILBERT  N  (2006)  Agent-­‐based  Models.  Series:   Quantitative  applications  in  the  Social   Sciences.  Sage  Publications.   AMBLARD  F  et  PHAN  D  (2007)  Modélisation  et   Simulation  multi-­‐agents:  applications  pour  les   Sciences  de  l’Homme  et  de  la  Société.  Hermès   Editions.   TREUIL  JP,  DROGOUL  A  et  ZUCKER  JD  (2008)   Modélisation  et  Simulation  à  base  d’agents.   Dunod  &  IRD  Editions.  

Slide by Alexis Drogoul

55

Les  ou5ls  pour  la  modélisa5on  et   simula5on  de  systèmes  complexes ! !

Benoit  Gaudou

UMR  5505  IRIT,  CNRS  /  Université  de  Toulouse  -­‐  benoit.gaudou@ut-­‐capitole.fr

56

Etapes  de  modélisa5on

Etape 1: définir les questions de modélisation

Etape 7: explorer le modèle

Etape 2: identifier les éléments (entités, dynamiques) à modéliser Etape 3: collecter les données

Etape 6: calibrer le modèle

Etape 4: définir les agents (caractéristiques, dynamiques)

Etape 5: implémenter le modèle 57

Etapes  de  modélisa5on Etape 2: identifier les UML... Approches participatives

éléments (entités, Etape 4: définir les dynamiques) à modéliser Etape 1: définir les Méthode ARDI agents questions de (caractéristiques, modélisation dynamiques) EtapeGénération 3: population 
 Manipulation SIG

collecter les OpenJUMP

données synthétique

QuantumGIS

Etape 7: explorer le modèle

Etape 6: calibrer le modèle

YANG

Etape 5: implémenter le modèle 58

Exemple  de  modélisa5on  par5cipa5ve

Serge Bobo Kadiri, Dschang University, Cameroon {[email protected]}! Christophe Le Page, CIRAD Montpellier, France {[email protected]}

59

Exemple  de  modélisa5on  par5cipa5ve

60

La  méthode  ARDI Une  méthodologie  de  co-­‐design  d’un   modèle  conceptuel  des  interactions   socio-­‐environmentales  dans  un   système  socio-­‐écologique.   !

Actors! Resources! Dynamics! Interactions

De  l’identification  d’un  problème…   ...  à  une  question   ! !

Inspiré  des  slides  de  Christophe  LE  PAGE,   MISS-­‐ABMS,  Montpellier,  September   2013

61

Co-­‐construc5on  d’une  représenta5on  partagée  en  4  étapes A  =  Acteurs/  intervenants   R  =  Ressources   D  =  Dynamiques/  processus   I  =  Interactions   !

Chaque  étape  correspond  à  un  type  particulier  de  question.   !

1.  Quels  sont  les  acteurs  principaux  qui  interagissent  avec  la  rivière   et  son  débit  ?     2.  Quelles  sont  les  ressources  en  relation  avec  le  débit  ?   3.  Quels  sont  les  principaux  processus  intervenant  dans  the  bassin   Adour-­‐Garonne  et  qui  affecte  le  débit  en  eau  ?   4.  Comment  chaque  acteur  utilise  la  ressource  ?   62

Etapes  de  modélisa5on Etape 2: identifier les UML... Approches participatives

éléments (entités, Etape 4: définir les dynamiques) à modéliser Etape 1: définir les Méthode ARDI agents questions de (caractéristiques, modélisation dynamiques) EtapeGénération 3: population 
 Manipulation SIG

collecter les OpenJUMP

données synthétique

QuantumGIS

Etape 7: explorer le modèle

Etape 6: calibrer le modèle

YANG

Etape 5: implémenter le modèle 63

Yang  :  Yet  Another  Network  Generator YANG  (Yet  Another  Network  Generator)   est  un  outil  dédié  à  la  reconstruction  de   réseaux  plausibles  à  partir  de  règles   locales.   !

Il  a  été  appliqué  à  la  reconstruction  de   réseaux  sociaux  au  Kenya,  de  réseaux   sociaux  des  solidarités  économiques   sur  l’île  de  Mayotte  et  d’un  réseau   neuronal  à  partir  d’études  neuro-­‐ biologiques.  

Yang  :  http://sourceforge.net/projects/yang-­‐j/

64

Yang  :  exemple  de  réseau  produit  sur  l’exemple  du  Kenya

65

Etapes  de  modélisa5on Etape 2: identifier les UML... Approches participatives

éléments (entités, Etape 4: définir les dynamiques) à modéliser Etape 1: définir les Méthode ARDI agents questions de (caractéristiques, modélisation dynamiques) EtapeGénération 3: population 
 Manipulation SIG

collecter les OpenJUMP

données synthétique

QuantumGIS

Etape 7: explorer le modèle

Etape 6: calibrer le modèle

YANG

Etape 5: implémenter le modèle 66

Références

•GAMA  :  https://code.google.com/p/gama-­‐platform/   •Netlogo  :  http://ccl.northwestern.edu/netlogo/   •Cormas:  http://cormas.cirad.fr/   !

•Méthode  ARDI:  http://cormas.cirad.fr/pdf/guideARDI.pdf   !

•Yang  :  http://sourceforge.net/projects/yang-­‐j/   !

•SIG:  OpenJUMP  :  http://www.openjump.org/   •SIG  :  Quantum  GIS  :  http://www.qgis.org/   !

•Gephi  :  http://gephi.org/   •OpenMole  :  http://www.openmole.org/ 67

ARDI  :  références Etienne  M.,  2009.  Co-­‐construction  d'un  modèle  d'accompagnement   selon  la  méthode  ARDI  :  guide  méthodologique.  Cardère  éditeur,   Laudun,  71  p.   !

Etienne  M.,  Du  Toit  D.,  Pollard  S.,  2011.  ARDI:  a  co-­‐construction  method   for  participatory  modelling  in  natural  resources  management.   Ecology  and  Society  16(1):  44.  [online]  URL:   http://www.ecologyandsociety.org/vol16/iss1/art44/   ! !

•Méthode  ARDI:  


http://cormas.cirad.fr/pdf/guideARDI.pdf   68

Reproducing  and  exploring  
 past  events  using  
 agent-­‐based  geo-­‐historical  models Nasser  Gasmi(a,c,e),  Arnaud  Grignard(a),  Alexis  Drogoul(a,d),  Benoit  Gaudou(b),
 Patrick  Taillandier(c),  Olivier  Tessier(e)  &  Vo  Duc  An(a)   Prelim inary   proof   of  con cept   of  the  ARCH IVES   projec t
 (a)  UMI  209  UMMISCO,  IRD  /  UPMC
 (b)  UMR  5505  IRIT,  CNRS  /  University  of  Toulouse
 (c)  UMR  6266  IDEES,  CNRS  /  University  of  Rouen
 (d)  JEAI  DREAM,  IRD  /  University  of  Can  Tho
 (e)  EFEO,  French  School  of  Asian  Studies

69

The  analysis  and  transmission  of  past  disasters  is  an  integral  part  of   disaster  management The  experience  of  past  disasters  allows  local  knowledge  to  be  used  to  develop   community  responses  that  both  help  to  raise  awareness  of  risks  and  also  help   prepare  for  improved  future  disaster  response  and  reconstrucDon  

Prevention! • Land use planning ! • Learning from events! • Technical measures

Inspired by Integral Risk Management Cycle, FOCP 2012

70

However,  being  able  to  learn  from  a  past  disaster  event  requires  that  3   different  issues  are  solved Issue  1:  The  availability  and  accessibility  of  the  data  concerning  this  event   Issue  2:  The  construcDon  of  relevant  informaDon  from  these  data   Issue  3:  The  reconstrucDon  of  coherent  «stories»  from  these  informaDon   ! ! ! ! ! ! ! ! !

This  is  what  historians  do,  but  it  would  be  helpful  to  do  it  in  a  more   systema5c  way  as  this  potenDally  concerns  hundreds  of  thousands  of  past   disasters.

71

The  quan5ty  of  digital  informa5on  about  past  risk  events  is  strongly   dependent  on  when  in  history  they  have  happened

Digi5za5on  of   physical  documents

Produc5on  of   digital  documents

Future

Past 500

1000

1500 1600 1700 1800

1900

2000

today

72

A  first  step  is  to  make  more  informa5on  available  through  the   exploita5on  and  automated  analysis  of  available  digi5zed  contents Ins5tu5onal  analysis  

Social  network   analysis  

(Web)mapping Analysis  of  digital   informa5on Digi5za5on  of   physical  documents Produc5on  of   digital  documents

Future

Past 500

1000

1500 1600 1700 1800

1900

2000

today

73

Geohistorical  modeling  is  one  solu5on,  which  extrapolates  the  digital   informa5on  available  in  order  to  produce  new  digital  informa5on   through  simula5on

Geohistorical  modeling  is  a   way  to  tell  «stories»  and  to   make  these  «stories»   accessible  to  anyone.   Simula5on  of   digital  models Analysis  of  digital   informa5on Digi5za5on  of   physical  documents Produc5on  of   digital  documents

Past

Future 74

We  focus  on  one  specific  event:    July  1926  floods  in  and  around  Hanoi   and  its  management  by  authori5es.

Context

Method

Model

75

1

   Context

   

76

Context:  July  1926  floods  in  Hanoi  (Vietnam,  Red  River  Delta)   Map  of  dykes  (1905)

77 http://www.icem.com.au/maps/high_res/3d_slope.jpg

The  loca5on:  Hanoi  in  1926

Contour lines (brown)! Lakes (blue)!

Buildings(red)!

Red River (blue)!

6"

78

The  event:  floods  and  dikes  break  in  Summer  1926 Chronology:

! - 25th to 30th of July: increase of water level and main dyke breaches

Breach at Gia Quất


Dykes Breaches

28th, evening (old dyke)
 29th, at 9 AM (new dyke)

! - 31th of July to November: plugging of dykes

Hà Nội downtown

Breach at Ái Mộ 
 29th, at 4 PM

Breach at Lâm Du
 29th, between 4 PM and 5PM

79

2

Method

 

80

Source: inspired by David Sheeren’s presentation at MAPS5

Issue  1:  Building  of  a  comprehensive  and  navigable  corpus  from  the   heterogeneous  set  of  archives.   v First:  delimitation  of  the  system:   Ø event:  floods  of  Red  River  in  July  1926   Ø study  area:  Gia  Lâm  (district  of  Hanoi)  

   

v Identification  of  sources:  

Contour lines (brown)!

Ø The  NaDonal  Archives  Center  #1  (Ha  Nôi,   Viêt  Nam)   Ø The  French  mapping  agency  -­‐  IGN  (Paris,   France),   Ø The  French  School  of  Asian  Studies  -­‐  EFEO   (Ha  Nôi,  Viêt  Nam).

Lakes (blue)!

Buildings(red)!

Red River (blue)!

6"

81

Issue  2:      Representa5on  of  this  corpus  in  its  mul5ple  (spa5al,  temporal,   social)  dimensions  so  that  it  can  be  manipulated  and  explored  freely  by  users.   v to  create  accurate  GIS  data  from  the  disparate  maps  available  in  the  corpus   v to  integrate  temporal  informaDon  and  to  offer  the  same  querying  and  navigaDon   faciliDes  in  Dme  than  the  ones  exisDng  for  2D  and  3D  spaDal  data.  

82

Issue  3:  The  reconstruc5on  of  coherent  «stories»  from  these   informa5on   Building  of  models  of  the  reality  depicted  by  the  corpus  so  that  they  can  offer  an  account   of  what  happened  but  also  become  the  objects  of  experiments:   Ø hydrological  sub-­‐model,   Ø crisis  management  sub-­‐model.

Experimental  approach  based  on  hypotheDcal  reasoning  («what  would  have  happened   if  ...»,  «what  effect  this  decision  could  have  had  on  ...»)...

https://code.google.com/p/gama-platform/ 83

3

Modeling  spa5o-­‐temporal  dynamics  
 of  the  event

 

84

Hydrological  model:  collect  data v Data  available:   Ø Digital  Elevation  Model  (DEM)   Ø Shapefile  of  the  dykes   Ø Shapefile  of  the  buildings   Ø Shapefile  of  the  Red  river   Ø Shapefile  of  the  lakes

Hydrological  model:  floods  as  diffusion  on  a  regular  grid v Advantages   Ø Simple  to  understand  and  to  implement   Ø Require  little  data   Ø Allows  simple  integration  of  shapefiles  and  DEM  data  

v Drawbacks   Ø The  Digital  Elevation  model  plays  a  key  role  (high  resolution  -­‐>   time  consuming,  low  resolution  -­‐>  imprecise)

v Calibrations  using   historical  data

water height of the highest dykes/ buildings located

altitude

height

The  crisis  management:  from  textual  documents  to  agent-­‐based  model

Hierarchical organization

Set of documents 
 from Archives

87

The  crisis  management  sub-­‐model Given:
 -­‐  the  hydraulic  model
 -­‐  the  description  of  the  relationship   between  actors   !

Aim  of  the  model   Introduction  of:
 -­‐  actors’  actions  against  floods
 -­‐  how  orders  and  information  are   transmitted  through  the  actor  network   !

Question
 How  orders  and  information   transmissions  induce  the  building  of   small  dykes  ? 88

2  separated  models  linked  by  dykes

89

Build  s mall  d Simplifica5ons ykes!
 We  ca nnot  d o  anyt >
 -­‐  we  focus  on  the  reaction  of  actors  


to  the  floods  in  first  days  

!

On  actions:
 -­‐  as  physical  actions,  we  focus  only  on  the   building  of  small  dykes.
 -­‐  we  do  not  consider  actors  that  do  not   follow  orders.   !

On  dynamics:
 -­‐  top-­‐down  order  chain  (orders  to  local   authorities  to  builds  small  dyke)
 -­‐  bottom-­‐up  information  chain  (local   authorities  transmitting  information  of  help   need)   Technically:  use  of  FIPA-­‐ACL  to  manage   communication  between  agents

90

Issue  3:  The  reconstruc5on  of  coherent  «stories»  from  these   informa5on   Model  integraDng:   Ø hydrological  sub-­‐model   Ø crisis  management  sub-­‐model

Experimental  approach  based  on  hypotheDcal  reasoning  («what  would  have  happened   if  ...»,  «what  effect  this  decision  could  have  had  on  ...»)...

https://code.google.com/p/gama-platform/ 91

MABS  2014,  Paris,  France,  May  5th-­‐6th,  2014.

Conclusion

92

Conclusion:  first  achievements  and  perspec5ves v Still  a  preliminary  proof  of  concept.   v What  we  have:   Ø A  huge  dataset  (maps,  reports,  ...  )  about  a  parDcular  case   Ø A  first  model  that  has  everything  to  reproduce  the  crisis  and  its  management  (during  first   days)   Ø A  very  interesDng  case  study  (from  a  social  point  of  view)  

!

v Main  perspective:  automatic  generation  of  actors  and  their  behavior  from   textual  documents  (e.g.:  using  process-­‐mining  tools,  SNA...)   v Main  «results»:     Ø «Formal»  model  of  the  organisation  (which  lets  appear  difference  between  theoric  and   actual  organization)   Ø a  reflexion  with  Historian  about  the  role  and  the  interest  of  simulaDon  for  historical  research   and  Digital  HumaniDes  in  general.    

Ø the  interest  to  not  reproduce  the  actual  event  (e.g.  not  the  same  breach  locaDon)  in   order  to  be  able  to  test  hypotheses

93

Floods  in  Hanoi    (2008)  ...

94

The  MAELIA   project:   ! A  multi-­‐agent  platform   t o   d eal   w ith   ! water  scarcity  problems Frédéric  Amblard,  Yves  Auda,  Jean-­‐Paul  Arcangeli,  Maud  Balestrat,  Marie-­‐Hélène   Charron-­‐Moirez,  Benoit  Gaudou,  EDenne  Gondet,  Yi  Hong,  Romain  Lardy,  Thomas   Louail,  Eunate  Mayor,  Pierre  Mazzega,  Clément  Murgue,  David  Panzoli,  Sabine   Sauvage,  José-­‐Miguel  Sanchez-­‐Perez,  Christophe  SiberDn-­‐Blanc,  Patrick  Taillandier,   Olivier  Therond,  Nguyen  Van  Bai,  Maroussia  Vavasseur

95

Context

96

The  Adour-­‐Garonne  Basin:  a  structural  water  deficit

Hydroelectricity production Storage capacity

Irrigated area

Fernandez et Verdier Since  1950-­‐60  development  of  water  storage  in  dams  for  hydroelectricity  :  water   releases  in  winter   !

Since  1980  development  of  important  irrigated  areas:  agricultural  water   consumption  in  summer  is  up  to  80  %  of  total  consumption  during  the  low-­‐flow   period   !

Current  water  storage  capacity  is  inadequate  to  meet  temporal  and  spatial   distributions  of  water  needs

97

Water  crises During   low-­‐flow   periods   in   some   watersheds,   river   flows   are   regularly   measured   under   the   regulatory   threshold   (DOE)   which   guarantees   a   normal  functioning  of  the  aquatic  ecosystems  

Watersheds  with  recurrent     river  flow  <  the  regulatory  thresh

During  low  water   period,  irrigation  =   75%  of  water  

The  ways  to  manage  water   • Low  water  period  management   – Water  releases  from  dams   – Withdrawal  restrictions  (issue  of  drought   decree)   • Long-­‐term  policies   – Building  of  new  resources   – Withdrawal  regulations

Evolution  of  the  water  management  gouvernance !

Since   2009,   to   avoid   regular   water   crisis   French   government   is   instituting   a   new   regulation   of   agricultural  water  withdrawals   Determination  of  new:   -­‐ water   Volumes   Available   for   Agriculture   (VAA)   Yellow  watersheds:   VAA  <  water  withdrawn   in  d at  watershed  level     Red  watersheds:  VAA    vehement  protests  of  farmers  

Main  ques5ons  to  be  handled  with  the  MAELIA  pla]orm  

What  are  the  social,  economic  and   environmental  impacts  of  the  various   alternative  of  definition  and  management  of   (new)  water  Volume  Available  for  Agriculture?   !

Robustness  to  climate  variability?   !

Technical  feasibility  and  social  acceptability?  

101

Objec5ves

Build  a  platform  able  to  simulate  the  evolution  of  water   resources  management  on  the  Adour-­‐Garonne  basin     Assess  impacts  of  alternative  water  management   policies  during  low  water  crisis  by  simulation.   Under  various  scenarios  of  climate  change   !

Space  and  time  scale  :   draining  basin  (Adour-­‐Garonne  basin:116.000  km²)  at   the  field  scale   over  30  years  at  the  day  scale

102

Approach

Approach:  agent-­‐based  modeling  of  (complex)   Social-­‐Ecological  Systems

« gestion spatiale de l’eau » (Narcy & Mermet, 2007)

6

Paradigm:  agent-­‐based  modeling  and  simulation:     agent-­‐based  models  can  be  versatile  and  heterogeneous.

SimPop  model     http:// www.simpop.parisgeo.cnrs.fr/

Alexis

First  steps  of  an  interdisciplinary  project • Partners  who  do  not  know  each  other,  with  their  own  methods,   conceptual  frameworks,  expressions  (words  and  semantic)   !

• Fields:  hydrology,  computer  science,  geohydrology,  agronomy,   linguistics,  sociology,  history,  software  engineering…   !

• A  model,  a  simulator,  a  multi-­‐agent  system  ??????   !

• A  project  dynamic  to  build   !

• 18  months  to  find  a  way…   • How  to  conduct  the  interdisciplinary  modeling  process?

106

The  MAELIA  interdisciplinary  modeling  method ARDI Ambiguity Knowledge

K & Data

SES Rep

Question

Q’

Data Model

Data Model’

Data Model

SES structure

SES structure and processes

Sensitivity analysis Qualibra.-validation

Q’’

Q’’’

Q

Collective  learning  (methodology/various  fields/  teamwork) 107

The  integrated  MAELIA  model

MAELIA:  spatial  processes Ecological  processes   • • •

Soil-­‐crop  model   Hydrologic  model   Weather  

Human  activities  (Decision   process)   • Farmer  decision  

– crop  allocation  plan   – crop  management   ! • State  services  decision:     Socio-­‐economic  processes   – decree  of  water-­‐use  restrictions   (phenomena)   (severity  &  spatial  extension)   • Demographic  changes  (INSEE,   • Dam  Manager  decision:     municipality  level)   – water  releases • Land  Cover  changes  (Corine  Land  Cover   database)   • Drinking  Water  Consumption   • Industrial  Water  Consumption Processes interact in space (field, farm, sub-watershed) and time (day) ➔ coupling of social and ecological processes

MAELIA: the structure of socio-hydrosystems for lowflow management Agricultural  model

Hydrologic  model

Normative     model Cognitive Resources

Other  water  uses  model Material Resources

Actors

MAELIA: the structure of socio-hydrosystems for lowflow management Agricultural  model

Each  farm  with     each  irrigable     and  non-­‐irrigable     islet

Normative   Each  d   am  and     modelregulation  sectors

Hydrologic  model

Water  ressources:   River  segments,  lakes,     pounds,  groundwaters

Each  domestic  and  industrial     Other  aw ater   uses  m odel withdrawal   nd   discharge   point  

MAELIA: the structure of socio-hydrosystems for lowflow management Agricultural  model

Hydrologic  model

An  integrated  representation   of  the  structure     of  water  management  situations   in  the  Adour-­‐Garonne  basin  

Normative     model

Other  water  uses  model

The  MAELIA  case  study First  application  of  MAELIA  to   the  up-­‐stream  part  of  the   Garonne  river     (from  Pyrénées  mountains  to   Toulouse)   !

Drainage  area:  6000  km2
 Length:  140  km   !

104  Elementary  Watersheds   !

2532  farm(er)s   27  000  active  field  plots  (with   crops)

Integration  principles

Integration principles

• Spatial  discretization  in  sub-­‐basins  /  watersheds  (Zone   hydrographique  (ZH)).

104 Zones 
 Hydrographiques in the MAELIA area.

Example on a ZH

source : Carthage

Processes at the day scale 1

Weather:  Rain,  Snow 5

Withdrawals   (irrigation,  domestic,  
 industrial) 6

Water  Flow  
 to  Downstream

2 Farmers  daily  activity

3

4

Water  Flow  from  Upstream

Plant  growth

7

Normative  model  (prefect,  police  …118 )

Processes at the year scale

2 Update  Economic  market

3

1

4

Water  volume  allocation

 Urban  sprawl:   -­‐ Land  Cover  change   -­‐ Water  consumption

Farmer  yearly  decision  
 (cropping  plan)

119

20

MAELIA  :  Farmer  decision  model A  Belief-­‐Desire-­‐Intention  architecture  to  represent  the  farmer’s:

– multi-criteria choice of the cropping plan according the belief theory on 4 criteria : profit, variability of profit, workload and similarity to the last Strategic decision cropping plan (can be switch off)   (year) – Memorize yields, prices, water available, workload

 

Operational decision (day)

Different operations (some just for workload constraints) :   – Tillage   – Sowing a field   – Protect cultures   – Surface tilling   – Fertilise a filed   – Irrigation of a field   – Harvesting of a field

MAELIA  :  soil-­‐crop  model Priority  to  simulate  realistic  crop  yields  over  the  Adour-­‐Garonne   Basin  without  great  and  often  problematic  calibration  work     !

➔ Empiric  crop  model  developed  by  INRA  in  Toulouse  called   “Jeu  d’O”     !

Developed  step  by  step  according  results  of  agronomic   experiments  in  the  AGB  during  the  last  20  years   !

It  represents  effect  of     -­‐ climate,  soil  and  cropping  system  on  water  soil  dynamics  and   yield  for  the  eleven  main  crops  of  the  AGB     -­‐ cropping  system:  tillage,  sowing  date  and  irrigation

MAELIA  :  the  hydrologic  model Selection  of  the  SWAT  model  :     -­‐ applied  to  various  contrasted  situations     -­‐ a  great  user/developer  community     -­‐ open-­‐source     -­‐ possibility  to  define  the  size  of  sub-­‐ watersheds  to  adapt  the  model  to  the   investigated  agro-­‐hydrological  issues   !

Re-­‐implementation  into  MAELIA  of  the  SWAT   formalisms  representing  :   -­‐ The  snow  accumulation  and  smelt   -­‐ The  land  phase   -­‐ The  routing  phase   -­‐ The  hydrology  (input)  of  dam  and  pound   !

Elementary  Watersheds  used  as  “sub-­‐ watershed”

Elementary  watersheds   used  as  SWAT’  watershed

Conclusion

Project  agenda  and  perspective • Sensitivity  analysis:     • over  30  (hydrolic  model),  7  (farmers,  with  forcing  cropping   plan)  or  37  parameters  (both  processes)   • Sensitivity  over  14  outputs   • Spatial  Sensitivity  (of  hydrologic  model)   • Positive  consequences:   • bugs  detection   • question  precision  of  some  forcing  data  (e.g.  refine  the   number  of  slope  and  altitude  classes  in  inputs)   • Calibration:  multi-­‐objective:  reproduce   •  water  flows  and   • anthropic  dynamics

Application  example:   Clément’s  Murgue  thesis • Objectives:  Propose  method  and  tools  to  design  and  assess   alternative  uses  of  the  agricultural  space. Imagine  possible  alterna5ves:  

….#

Cropping  plans:  Crops,  spaDal  distribuDon   Water  management  strategies  

    Simulate  in  5me/space:     !

Modeling  &  simulaDon  (using  the  MAELIA  plaworm)  

Assess  each  alterna5ves        

Par$cipa$on*

Needs  in  irrigaDon:  how  many,  when,  where?   Consequences  on  hydrology   Conséquences  on  farms  

Variabilité)clima,que:)

Modélisa)on+

Evalua&on)

Hydrology  in  MAELIA

http://code.google.com/p/gama-platform/

MAELIA