Transport network models comprise of frameworks for the transportation infrastructure, and their development is based on a number of intrinsic contributory factors of which environmental features are a critical part. Transport network models are thus used as frameworks to formulate systems.
A variety of intrinsic factors across disciplines can influence such systemic formulations in an interlinked manner to deliver desired services. These concomitant factors can display incredible variance of numerous disciplines and categories.
H.P. White and M.L. Senior in their 1983 book titled ‘Transport Geography’ attempted to simplify this diversity of concomitant factors influencing the development of transport network models (GeographyNotes.com, 2017). They listed five types of factors –
- Historical factors – these include the pre-existing factors present such as the patterns of land-use, previous development of regions and settlement patterns, levels of technological infrastructure already present, patterns and locations of systems already in order, etc.
- Physical factors – these include the physiographic controls that facilitate and constrict the development of transport networks, and the geological and climatic features of the target locations.
- Technological factors – these include the technological support available and also involve evaluations of technological advances, including their effects.
- Economic factors – these involve evaluations of possible costs involved in building and managing transportation networks, the economic services involved and the workings of prospective price mechanisms.
- Social and Political factors – these include an entire gamut of social and political factors influencing the development of transport network models such as government policies, meta-political factors, working conditions, safety, the social effects of laying transport networks, etc.
These factors, although they are simplified in this nomenclature, are also interconnected, and for this reason, it is also necessary to take space and time into account. This can involve looking at local conditions and evaluating them over different time periods in terms of the concomitant factors listed above, which can serve to simplify analyses for frameworks.
This can form archetypes in terms of relational associations between the factors and space-time. For example, local conditions can be said to be associated with local environmental and climatic patterns in terms of physical factors. Similar indexical archetypes can be formed out of other categories, such as local conditions being associated with roads in terms of technological factors as one archetype (Table 1).
This helps in simplifying spatial and temporal frameworks often also with the use of previous case studies by analyzing them under the archetypal indexes of the categories listed above, whose interconnectedness is now simplified.
Table 1: Example of index used to classify results from the interface of factors and space-time
The development of transport networks utilizes several models for understanding the mode of development of the system. Such models can be quite specific regarding the mode of development of the transport networks they study. Some models lay a priority on spatial dimensions, some on modes of transport, while other approaches lay emphasis on a factor, such as analyzing the economic aspects of transport networks in their development. Among Transport Development Models, some notable models are as follows –
Rimmer in 1977 presented a four phase model for the analysis of interrelated development of transport networks between developed countries and third world nations. The model traces the impact of colonialism on the development of transport systems in these nations. The first phase begins with no links between the two, with more badly made roads, a limited amount of tracks for trains, etc with a socio-economic order with restricted means and ends.
The early colonial phase is the second phase, and consists of exploration of the regions by colonial powers through sea routes, beginning with seafaring trade and limited settlements on these nations by colonial powers.
The third phase occurs post colonization, and here the colonial powers engage in laying their basic infrastructure such as roads and railways along with radical changes in the political and economic organization of Third World nations.
The last phase in this model is the neo-colonial stage, involving diversification and modernization of the transport systems. These transport networks were aimed at resource extraction from colonized nations by the colonial powers.
Vance in 1970 presented a model for the development of transport links in North America whose development influenced the growth of an urban hierarchy. The model charts how favourable trading results due to a better transport infrastructure for North Americans due to better manufacturing facilities facilitated urban lifestyles.
Gould’s Spatial Exploration Model constructs how transport networks are used for resource extraction from areas previously unexplored territories. The model explores how spatial utilization of unexplored areas through the development of transport systems facilitates resource extraction from these regions (GeographyNotes.com, 2017). Most Transport Development Models involve the development of economic landscapes and facilitate optimum utilization and management of resources.
Most modelling for transport networks happen as extensions for urban developmental issues. An example is the Bus Rapid Transit (BRT) corridors established in Delhi, that were recently dismantled for causing traffic jams instead due to poor management.
The high density of cars in Delhi has contributed to the failure of the BRT corridors in Delhi, which has been a success in most other cities worldwide. The high amounts of congestion in Delhi’s roads creates a ubiquitous traffic problem in Delhi, and BRT corridors were frequently utilized by other vehicles to get out of a fix in a traffic jam. This follows bad policing and management of the BRT corridors in Delhi. A good model would take all anomalies into account and anticipate the exceptions caused by the high density of vehicles in Delhi and the ubiquitous resulting traffic jams. The BRT in Delhi is an example of a model not being applied correctly.
Since the original usage of transport network models concerned urbanization by industrialized societies, with the arrival of data processors by the 1950s, mathematical large-scale modelling of transport systems gained prominence.
In this, the technological and economic factors came to become the dominant factors in formulating transport development models, to the disadvantage often of other factors such as historical and physical (environmental) factors. This could lead to problems such as those experienced by Mumbai when flooding occurs concomitantly due to a lack of attention to drainage while constructing road and rail networks.
In contemporary times the widespread applicability of technology along with the increasing costs involved in laying transport infrastructure have placed technological and economic factors at the forefront in the formulation of transport development models. The older patterns of technological infrastructure are overlaid with newer patterns of technology, such that the metropolitan gains precedence over the local.
The frameworks for developing transport systems exhibit a potential for judicious resource utilization, and for this to occur, it would require an integrated planning approach that involves a better understanding of all factors involved in the formulation of these transport systems. This would require site-specific, temporally proper and referentially correct transport systems, which would be a step forward in the sustainable development of transport systems.