Indices Of Arrangement

It would be illusory and quite tedious to propose an exhaustive list of indices of spatial arrangement suggested in the literature. The most productive fields of research in this respect are certainly those of the geography, ecology, regional sciences and the numerical image processing. From the methodological point of view, most significant is to seize the aspects of the spatial arrangement which one wishes to describe through indices, the way of interpreting them, as well as their context of use.

The context of application of the indices of arrangement is influenced by the following factors:

At the scale of the study area: “the structure”

On the level of the spatial objects On the level of a group of objects with a common thematic property On the level of the study area
12 spatial objects 4 objects with a class of average
aptitude for agriculture
Distribution of the thematic
properties of the 12 objects
Figure 3.1

At the scale of neighborhood of the unit of observation: “the texture”

In object mode, for each unit of observation (object) In image mode, for each unit of observation (cell)
Immediate neighborhood (of 1st order) of the object with enhanced limits in red Immediate neighborhood (window 3x3) and of 2nd order (window 5x5) of the central cell
Figure 3.2

In order to present a synthetic and structured vision these descriptors of spatial arrangement for zonal units, we will organize this description according to the factors of "scale of description" and of "dimension" indices. In this Unit only major indices of spatial arrangement will be presented, those one can find in GIS or spatial analysis or image processing software (Idrisi, Fragstats, Envi…).