Survey and Information

What do you understand by spatial and non-spatial data? Why is it important in planning?

There are two basic categories of Data in Surveying depending on the nature of data collected for planning purpose from the field:

1. Spatial Data
2. Non-spatial Data

The categorization of the data types is based upon the non-physical measures present on the society are non-spatial data which count in the process of planning as the driving factor of the society for which the planning is carried out. The spatial data are calculated according to the real and natural physical quantities in the nature which is basically measured with the different surveying tools.

1. Spatial Data:

 Spatial data is the dimensioned measure in the survey. The length, breadth, height, location, position, orientation, topography etc. measured in the spatial survey are called as spatial data. The spatial data can be easily shown in the maps as the coordinates and position of any geographical elements on the surveying territory.

Representation of Spatial data can be expressed in terms of: Scalar Data and Vector Data.

So, the location is defined in spatial data. These are in the form of graphic primitives that are usually: Points, Lines and Polygon.

For example: if the survey of an open land plot is carried out, then aspects of spatial survey and significance of this acquiesced data is as: the length of the diagonals, area of the plot, location of the plot (longitude / latitude), contour of the plot, slope etc. Hence in the spatial data there is always the relationship of one data and another in terms of spatial measures.

1. Non-spatial Data:

The survey data which is independent of the location or the position is non-spatial data. The information which is acquired from the non-spatial survey is non-spatial data. In this type of survey, the non-physical information are acquired by means of non-physical tools of survey because of its different nature. In non-spatial data there are basically statistical data, attribute or characteristic datasets. The non-spatial data are linked to the spatial data in GIS that define the location.

Non-spatial data is that information which is independent of all geometric considerations. For example: the height of a person, the mass of the substance etc. come under the non-spatial data where these information don’t have any relation to the geological position / location.

On the other hand, the non-spatial data is a set of social data. This way of interpretation leads us to the category of social survey where the considerations of the social status of the people, economic conditions, religious believes, health conditions, migration patterns, cultural status of the people etc. is surveyed. In the collection of data for this type of survey the different tools are used than the spatial survey. The questionnaires are the important tools to acquire these data.

Hence, there are very fundamental differences between spatial and non-spatial data as:

• Spatial data are generally multidimensional and auto correlated.
• Non-spatial data are generally unidimensional and independent.

The importance of Spatial and Non-spatial data in planning can be shortly described in following points:

• Spatial data directly gives the relative position of the place, services, existing structures etc. which is beneficial to identify the possibilities of planning of that particular place.
• Spatial data contains the dimensions, for eg. Spatial distribution of resources, as its basic components which provide in relation to the non-spatial data, for eg. Economic data, in the planning gives the feasibility of the planning attempted.
• Spatial data gives the geographic status of the place where we can find the topography, contours, ecology etc. which gives the idea of intervention measures needed to plan that area.
• Non-spatial data contains the information regarding the socio-economic conditions, population, views of the people etc. which are very important in planning process as the inclusive and participatory planning.
• The social data in the non-spatial data provide the theoretical base for that area and facilitate the process of planning since the planning is different for the different place and the specific and particular nature of the society results the planning fundamentally.

Hence there are fundamental differences in the spatial and non-spatial data from acquisition of any type of data to planning and finally implementation. Both types of data are used by GIS to give out a comprehensive status of the place including its inhabitants for which the planning is done for.

Urban Planning, Pulchowk Campus

Module: Survey and Information (Assignment)

Tutors: Suman Meher Shrestha, Lecturer /  Apil KC, Assist. Lecturer

Department of Urban Planning, Pulchowk Campus

Institute of Engineering, Tribhuvan University

Date: April 1, 2016