Data Requirements for Irrigation Modelling

							Data for Irrigation Modelling

      Hector M Malano
              Outline

•   Modelling: what processes?
•   What data gaps are there?
•   Frequency of collection
•   Level of disaggregation
                    Processes(1)?
• Water allocation (system & catchment level)
   – Assessment of allocation policy changes, e.g. env flows,
     water trading, economic impact, infrastructure planning,
     etc.
   – Data requirement:
      • Seasonal disaggregated crop mix (crop types) at demand centre
        level is a critical input for allocation modelling
      • Frequency: Seasonal or more frequent depending on cropping
        pattern (NSW more variable than Victoria)
• Distributed evapotranspiration and soil moisture:
  Water balance modelling at farm and area levels
  (needs multitemporal analysis)
                              Processes (2) ?
• Water application                                                   Inflow and Second Basin
                                                                                                  Point
                                                                      Advance
                                                                                                 Outflow
   – HC is a critical parameter
     for model parameterisation                                     Inflow and     First Basin
                                                                    Advance
     and real-time control logic
                                                         Supply

  Kotiakov          Z  Atb  Ct
                    S 2  2hstr K s ( s  i )        K  Ki  K s ( h  hstr )( s  i )
  Parlange    top                             ln 1   s       
                    2 (1   )(K s  Ki )  2
                                                        I s  Ki  ( K s  Ki )(I s  K s )
          S 2  2hstr K s ( s  i )  2(1   )K s ( h  hstr )( s  i )   I s  K s 
                                                                             ln  I  K 
                                                                                           
                               2(1   )(K s  Ki )  2
                                                                                s       i 
               Processes (3)
• Soil salinity: Correlation of airborne data with soil
  moisture content and salinity point measurement
  (0-0.5 m) for use in salinity mapping (Data
  available for Coleambally).
• Correlation of soil permeability with recharge
  discharge areas to predict impacts of irrigation
  and drainage options.
• Channel Seepage: Identification of seepage
  zones. Correlate shallow soil saturation
  measurements (10-20 m) with EM surveys.