Book summary
Modelling Land-Use Change
Progress and applications
Koomen, E., Stillwell, J., Bakema, A., & Scholten, H. J. (Eds.). (2007). Modelling land-use change:
Progress and applications (Vol. 90). Springer Science & Business Media.
, 1
Chapter 1 MODELLING LAND-USE CHANGE
1.1 INTRODUCTION
Land-use models have tended to remain relatively under-used ‘black boxes’, producing little
more than nicely coloured maps. Perhaps the lack of attention to the development of useful
applications in the field of land use is related to the extensive array of existing models, the
different approaches they take, and the relative complexity of their underpinning theories and
methods of application.
1.2 CHARACTERISING LAND-USE CHANGE MODELS
Land-use change is a complex, dynamic process that links together natural and human
systems. It has direct impacts on soil, water and atmosphere and is thus directly related to
many environmental issues of global importance.
Land-use change models can be defined as tools to support the analysis of the causes and
consequences of land-use change.
One of the most important distinctions between land use models refers to static as opposed
to dynamic models.
- Static (or cross-sectional) models directly calculate the situation at a given point in
time.
- Dynamic models work with intermediate time-steps, each of which might become the
starting-point for calculating the subsequent situation. Dynamic modelling, therefore,
takes possible developments during the simulation period into account, providing a
richer behaviour and the possibility to better mimic actual spatial developments.
Land-use change models can also be characterised as dealing with either transformation
or allocation.
- Transformation models start from the current land use and simulate the possible
conversion into another land-use type, e.g. based on a transformation probability or
the status of surrounding locations.
- Allocation models allocate a certain type of land use to a location based on its
characteristics. Current land use may thus be one of the factors influencing locational
characteristics, but it is not necessarily preserved in future land use. This approach to
simulation basically starts with an empty map.
Approaches to simulating land-use change may be either deterministic or probabilistic.
- Deterministic approaches apply strict cause-effect relations
- Probabilistic approaches consider the probability of land-use changes taking place.
The essence of this second approach is the introduction of an element of uncertainty.
A type of use is attached to a location based on an estimated probability, rather than
following a straightforward deductive approach. In some cases, a random error-term
is added to express the uncertainty in the explanatory factors.
, 2
Another common distinction is the one made between sector-specific and integrated
models.
- Sector-specific models focus on one part of the land-use system (e.g. housing,
employment, agriculture) and describe that part as precisely as possible.
- Integrated models consider the mutual relationships between these sectors. Truly
integrated models also incorporate the feedback of the land-use system with other
related systems such as climate, hydrology or transport.
In relation to the spatial level of detail, both zones (polygons) and grids (raster) are used.
Models that use grids often make use of geographical information from other sources, thus
having access to valuable base data.
1.3 THEORIES AND METHODS OF LAND-USE MODELLING
1.3.1 Economics
Models for simulating future land use exist in many different types and forms, but they all rely
on a limited number of theories and methods. Economic theories, for example, are often
used to explain land-use patterns and their dynamics.
For a number of reasons, land is a special economic asset:
- The supply of land is fixed, creating specific demand-supply relations.
- Every parcel of land has a fixed location with its associated unique features in terms
of soil quality, gradient, altitude, accessibility etc.
- The land use at a certain location influences its surroundings
There are three important land price and land use theories:
- Ricardo (1817, in Kruijt et al., 1990) explained land prices in terms of differences in
soil fertility levels or, more generally speaking, in terms of land quality. Better quality
land is more profitable than lower quality land, and this difference leads to payment
of a higher price for the land.
- Von Thünen (1826) focused on the impact of distance and hence transportation
costs, to explain land-use patterns and land prices.
- Current economic analysis of land use often takes bid rent theory (Alonso, 1964) as
a starting point, focusing on the relationship between urban land use and the value of
urban land. Individual households and companies weigh up the land price,
transportation costs and the amount of land they need. This leads to a simple model
with decreasing land prices as you move away from the city centre. The land use
resulting from these assumptions is that of a typical monocentric city.
McFadden (1978) states that the probability that an individual selects a certain alternative is
dependent on the utility of that specific alternative in relation to the total utility of all
alternatives. When translated into land use, this approach explains the probability of a
certain type of land use at a certain location based on the utility of that location for that
specific type of use in relation to the total utility of all possible uses. The utility of a location
can be interpreted as the suitability for a certain use. This can be formulated as follows:
Modelling Land-Use Change
Progress and applications
Koomen, E., Stillwell, J., Bakema, A., & Scholten, H. J. (Eds.). (2007). Modelling land-use change:
Progress and applications (Vol. 90). Springer Science & Business Media.
, 1
Chapter 1 MODELLING LAND-USE CHANGE
1.1 INTRODUCTION
Land-use models have tended to remain relatively under-used ‘black boxes’, producing little
more than nicely coloured maps. Perhaps the lack of attention to the development of useful
applications in the field of land use is related to the extensive array of existing models, the
different approaches they take, and the relative complexity of their underpinning theories and
methods of application.
1.2 CHARACTERISING LAND-USE CHANGE MODELS
Land-use change is a complex, dynamic process that links together natural and human
systems. It has direct impacts on soil, water and atmosphere and is thus directly related to
many environmental issues of global importance.
Land-use change models can be defined as tools to support the analysis of the causes and
consequences of land-use change.
One of the most important distinctions between land use models refers to static as opposed
to dynamic models.
- Static (or cross-sectional) models directly calculate the situation at a given point in
time.
- Dynamic models work with intermediate time-steps, each of which might become the
starting-point for calculating the subsequent situation. Dynamic modelling, therefore,
takes possible developments during the simulation period into account, providing a
richer behaviour and the possibility to better mimic actual spatial developments.
Land-use change models can also be characterised as dealing with either transformation
or allocation.
- Transformation models start from the current land use and simulate the possible
conversion into another land-use type, e.g. based on a transformation probability or
the status of surrounding locations.
- Allocation models allocate a certain type of land use to a location based on its
characteristics. Current land use may thus be one of the factors influencing locational
characteristics, but it is not necessarily preserved in future land use. This approach to
simulation basically starts with an empty map.
Approaches to simulating land-use change may be either deterministic or probabilistic.
- Deterministic approaches apply strict cause-effect relations
- Probabilistic approaches consider the probability of land-use changes taking place.
The essence of this second approach is the introduction of an element of uncertainty.
A type of use is attached to a location based on an estimated probability, rather than
following a straightforward deductive approach. In some cases, a random error-term
is added to express the uncertainty in the explanatory factors.
, 2
Another common distinction is the one made between sector-specific and integrated
models.
- Sector-specific models focus on one part of the land-use system (e.g. housing,
employment, agriculture) and describe that part as precisely as possible.
- Integrated models consider the mutual relationships between these sectors. Truly
integrated models also incorporate the feedback of the land-use system with other
related systems such as climate, hydrology or transport.
In relation to the spatial level of detail, both zones (polygons) and grids (raster) are used.
Models that use grids often make use of geographical information from other sources, thus
having access to valuable base data.
1.3 THEORIES AND METHODS OF LAND-USE MODELLING
1.3.1 Economics
Models for simulating future land use exist in many different types and forms, but they all rely
on a limited number of theories and methods. Economic theories, for example, are often
used to explain land-use patterns and their dynamics.
For a number of reasons, land is a special economic asset:
- The supply of land is fixed, creating specific demand-supply relations.
- Every parcel of land has a fixed location with its associated unique features in terms
of soil quality, gradient, altitude, accessibility etc.
- The land use at a certain location influences its surroundings
There are three important land price and land use theories:
- Ricardo (1817, in Kruijt et al., 1990) explained land prices in terms of differences in
soil fertility levels or, more generally speaking, in terms of land quality. Better quality
land is more profitable than lower quality land, and this difference leads to payment
of a higher price for the land.
- Von Thünen (1826) focused on the impact of distance and hence transportation
costs, to explain land-use patterns and land prices.
- Current economic analysis of land use often takes bid rent theory (Alonso, 1964) as
a starting point, focusing on the relationship between urban land use and the value of
urban land. Individual households and companies weigh up the land price,
transportation costs and the amount of land they need. This leads to a simple model
with decreasing land prices as you move away from the city centre. The land use
resulting from these assumptions is that of a typical monocentric city.
McFadden (1978) states that the probability that an individual selects a certain alternative is
dependent on the utility of that specific alternative in relation to the total utility of all
alternatives. When translated into land use, this approach explains the probability of a
certain type of land use at a certain location based on the utility of that location for that
specific type of use in relation to the total utility of all possible uses. The utility of a location
can be interpreted as the suitability for a certain use. This can be formulated as follows:
