P.O. Box 463

6200 AL

Maastricht

hvdelden@riks.nl

www.riks.nl

Hedwig van

Delden

Garry McDonald

Jasper van Vliet

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Integrating macro-economic developments and land-use

allocations in simulating urban dynamics

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Research context

Two research projects in New Zealand to develop and use spatial models for supporting planning processes policy impact assessment forecasting land-use developments application to a rural region: Waikato application to two urban regions: Auckland

and Wellington

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Land use change over time…

Land use dynamics are complex and exhibit self- organising behaviour Planners and policy makers have a decisive influence on future land use

Challenge!

Contradiction?

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Challenges

Simulation of spatial developments over time Incorporation of a range of drivers Dynamics driven by processes operating on

various scales Bottom-up and top-down interactions!

Development of a system for policy support Useful system for policy analysts in supporting

scenario studies and policy impact assessment Transparent system with access to data and

parameters for technicians and modellers

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Starting point…

Metronamica land use model Constrained cellular automata based

model Yearly time steps Time horizon 2025-2050 Spatial extent 100 x 100 km (Wellington) Spatial resolution 100 m (Wellington)

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Land useLand use

Time Time LoopLoop

&&

Stochastic Stochastic perturbatiperturbati

onon

0 0.5 1

randvt ln1

& & interaction interaction

weightsweightsSuitabilitySuitability

&&

AccessibilityAccessibility

&&

Transition RuleTransition RuleChange cells to the land

use for which they have the highest transition potential until regional demands are

met

ZoningZoning

&&

Land useLand useat time T+1at time T+1

TransitionTransitionPotentialsPotentials

==

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How to obtain regional demands?

Macro-economic model Input-output model Calculation of economic developments per

sector taking into account the interdependencies between sectors

Annual time step

Demographic model Age cohort model Calculation of the population per age cohort

based on birth, mortality and migration rates Annual time step

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Integrating socio-economics and land use

Demand side

Final demand ($)

Output ($)

Supply side

Change in final demand

($)

Reduction in output

($)

Land use allocation

- Spatial planning- Suitability - …

t-1

Land that could not be allocated

Conversion to land use demands (ha)

Demographic

developments

- Exports - …

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Integrating macro-economics and land use

Main benefit of using IO (or CGE) models is that the impact of land use can be analysed not only on one sector, but also on all other sectors

Dynamic coupling between macro-economics and land-use change Impact of socio-economic growth on land

use developments Impact of (limited) natural resources on

economic development The concept of the economic model had to

be stretched by calculating the demand in one year and the supply in another, not allowing an equilibrium in each year

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Conclusions on the modelling approach

Dynamic coupling between macro-economics and land use change Impact of socio-economic growth on land use

developments Impact of (limited) natural resources on

economic development Equilibrium approach of economic models

often poses conceptual conflicts with the simulation approach of dynamic land use change models

Being able to couple models technically doesn’t mean the coupling makes sense!

For future research it is recommended to focus first on the integration of the processes and next on the model implementation

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Thank you! hvdelden@riks.nl