July 10, 2011

II of II: Space, Informal Sector, and Central Place Theory

Location and land use have been long understood as key to functional economies, ever since the days of David Ricardo who described land as an inelastic factor in economic production.  Later, Christallar's Central Place Theory was able to advance the similar concepts, recognizing that market prices fluctuate according not only to demand, but also according to location and logistics, and therefore human settlements are spatially distributed according to the range of their products and the value (order) of exported goods.  Yet if Central Place Theory fully explained the 'why' and 'where' of human settlements, all cities, towns and villages would be distributed at equitable distances.  This is not possible because a collection of other factors determine the location and size of human settlements.  Although the list is not exhaustive, some of the most important factors are the following in no particular order:

1. Transportation and Communication Technology - varies by type of transport, carrying capacity of transport, speed (affected by density of traffic), and quality of transit/communication corridors.
Example: Although transportation and communication function differently, I would argue that both function toward the same mutual objective and that the value of productivity for one will inform the value of the other.  Access to paved highways, dirt roads, footpaths, water transport, airways, supply chains, phone networks, mail delivery, internet access are similar in economic and social gains.  The distinction is located not so much in their productivity, but rather the productivity over time.

2. Availability and supply of natural resources 
Example: What raw resources are available for food, repairing goods and automobiles, and construction such as water, lumber, pasture space and high yield soil ?

3. Availability and supply of processed resources
Example: What value-added resources are available for food, repairing goods and automobiles, and construction such as gasoline, steel, and pharmaceuticals ?

3. Concentration of social groups and cultural expectations for housing, land use, and production
Example: Rural households in India have traditionally subdivided land among the children of the family at adulthood, yet the continual subdivision eventually creates indeterminate zones of urbanization, leading to long stretches of 'urban-like' settlement along transit corridors between towns.  As the population rises the lines between rural and urban are less clear and the basis of settlement is rooted in sheer availability rather than utility/adaptability.

4. Location and efficiency of disposal systems for waste and excess resources
Example: Excrement, refuse, and drainage during rainy seasons through either structural intervention or permeability of soil.

5. Ratio of resources that contribute to security (scaled from regional such as defense capacities of natural terrain to family unit such as housing design) vs. hostility and expectations of outside threats.  
Example: Location of town at a mountaintop with farmland in the valley supports water flow to the crops but also creates a defensible position.

These factors interact in a give and take arrangement to facilitate the establishment and spatial determination of settlements.  For example, where ever two different systems of transportation intersect (such as river and an arterial road), one can always locate a settlement often occupied in proportion to the productivity of the transit routes.  Thus a city will always be located at intersection of a major highway and a large river while a small town will be found at the intersection of lesser used routes. Notably the significance of each of the above conditions are directly or indirectly economically determined.

Informal Sector and Urban Form
In the 1960's and 1970's the International Labor Organization promoted the concept of the informal economy so as to explain and measure the role of markets that are outside government regulation and institutional recognition.  Of course the term is rife with complication, considering the vast size and activity of these markets and the frequent confusion of informal activity with illegal.  Arguably, for most of the world's population, the informal marketplace is simply a matter of daily life and survival, and the workings of the formal economy are merely the actions of an inaccessible or poorly structured distant bureaucracies.  Due to the binary dissection of the global market, the immense overlap of formal and informal markets is poorly measured while the opportunities for valuation in local assets remains limited (such as through the failure of formal economies to recognize improved housing and settlement consolidation where no 'formal' terms of property ownership are established).  In many ways, the conception of markets as informal undermines the greater economy by failing to recognize the dynamism of productive, informal assets.

Location of Informal Settlements in Tirana Albania
Working both within and outside of formal frameworks, the informal sector modifies and determines urban form in a slightly different fashion than the rigid conception of Central Place theory would dictate. Historically, the wealthiest populations are located at the center of the settlement, where the most resources and logistical corridors overlap.  The concentration of wealth in the center promotes urban design and planning initiatives to maximize resources by creating a grid-like plan or some similar design.  The formalization of interior space consequently marginalizes spaces of production (preference is given to spaces of exchange, raising their value and consolidating the city center as a space of wealth) and the impoverished, leaving only the outskirts of the settlement for the poor along with industrial spaces and thus the phrase, "lives on the other side of the tracks." 

Bangalore Aerial View 
Bangalore Supply Corridors and Central Place Polygon
In other instances, usually when the concentration of wealth and division between social classes is not as severe, one could argue that informal activity could determine the regional establishment of settlements more akin to the demands of Christallar's assumptions as the informal economy is greatly determined by the principal of least effort.  Patterns in land use are going to be situated as closely together as possible to maximize resources at the lowest cost.  Thus clusters evolve, wherein similar businesses are all located in the same area and often adjacent to suppliers. 

As consequence of the clusters, even a single settlement that is seemingly chaotic can be quickly subdivided into land use types, supply lines, and in consequence, one can make inferences about the social composition of the neighborhood, such as local priorities and values. For example, the city of Bangalore is quickly deconstructed into something manageable.  Notably, the city is laid out as a collection of concentric polygons, not too far off from Christallar's hypothesis.


  1. Christaller's theory of 1933 is descriptive, but less than a decade later he is involved in an attempted practice to impose his theory onto parts of an occupied country. The Nazi German colonization of Poland and beyond. Here the theories of another German geographer Haushofer about needed 'Lebensraum' (space to live) for the Aryan race, combine with the Central Places theory of Christaller. The home grown 'specifics' of many centuries of human settlement are meant to be replaced by a generalized scientifically formulated imposed 'grid'. The reformatting of the land and the social structures it carries, becomes a mass violence historical event. There is both continuity and similarity in the role of geographers and their theories put into practice, be it extra European colonization, Soviet collectivization, or Nazi quest for Lebensraum: geometric patterns overwrite the idiosyncrasies of nature and human habitation.

  2. Hi Tjebbe, Thanks for the comment.

    I do believe you are correct that groups often quickly adapt theories and trends to meet an agenda and that common place geometry easily falls under the influence of such processes. Yet there are really two classes of model: both classes are determined by measurement, but one class is output as measurement and the other is output as metaphor. Too often planners and geographers get caught up in the poetry of metaphor when describing urban phenomena, and these metaphors are dangerously subjective. It is frequently at such times that their theories do more harm than good.