APPLICATIONS OF REMOTE SENSING AND GIS

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					     APPLICATIONS OF REMOTE SENSING AND GIS
                             IN LAND USE MAPPING
                                            Muhammad Adeel

Geographic Information System is a most important tool in many kinds of development planning for two
principal reasons. First it is oriented to the spatial component of development. This comprises the use of the
land for human settlements, the use of land resources as in agriculture and forestry, and the management
and protection of the natural environment. Second, GIS is oriented not solely to the purely geographic
aspects of planning, but to its informational contents. As a tool, GIS cannot itself can do planning or solve
problems in development. it can also provide major help in identifying trouble spots and in suggesting
possible actions. Land use mapping has been a lengthy and cumbersome procedure which needs to be
updated. The use of GIS and Remote Sensing can be helpful for time saving and efficient land use
mapping. It also adds the advantages of computer use to this process.

STATEMENT OF THE PROBLEM

Land use maps prepared by traditional approach of manual surveying have certain
limitations when we calculate their feasibility as compared to the technical and advanced
resources. These resources are available to us in the form of satellites and aero planes
which are capable of taking photographs at all scales.

Paper oriented maps are prepared by traditional methods of mapping. They have the
following common limitations.

        Land use map of an average size city requires time in months for manual surveys.
        It requires skilled surveyors and surveying instruments.
        Revision of a land use map also requires much time considerable costs because of
         manual physical surveys and data collection so such decisions are taken now and
         then because of the existing manual practices for land use mapping. Absence of
         up to date data results in poor planning practices in the cities and towns. For
         example, in our aces study area of Lahore development Authority the Land Use
         map was prepared at a scale of 1:10000 in 1992-93 by Survey of Pakistan. The
         character of the case study area has been changed by that time from rural
         hinterland to an almost fully urbanized land with some cultivation. But there is a
         serious lack of land use map revison after 10 years of map preparation of first
       land use map. It has resulted in inability of LDA to exercise proper and efficient
       land use and development control practices in the area.
      Some of survey areas might be inaccessible because of topography, natural
       hazards and other constraints. In this case traditional methods of land use
       mapping are very difficult to practice.
      Final output as land use map has certain questions on accuracy because of
       personal bias and instrumental errors.

On the other hand, land use is a continuous and ever changing process. In this case
changes remain un detective until the continuous revision of map. Ever-growing
population of results in complex land use activities. These activities need to be monitored
continuously for effective planning practice in an area.

Continuous monitoring of land uses from space or air (known as Remote Sensing) has
provided town planning an effective way to prepare land use maps and detect changes
frequently. The land cover picture is taken from space. Remotely sensed data can be
converted into land map using systematic process in a shorter time as compared to the
time consumed in manual land surveys. Use of Remotely sensed images and GIS has
proved to be very effective technique for land use mapping when time constraints of time
level of accuracy, data coordination & dissemination are taken into considerations.


RESEARCH OBJECTIVES
      To assess the potentials of Remote Sensing and GIS for land use mapping.
      To Identify and delineate different land use/land cover categories using high-
       resolution remote sensing data
      To prepare land use map of case study area and determine its accuracy in terms of
       confidence level




SCOPE AND LIMITATIONS OF THE STUDY

The project shows the process of converting a satellite image into a land use map with a
practical example of Lahore Raiwind Road area satellite imagery. In long run this
technique is more economical, time saving and efficient for data coordination. High-
resolution images provide accurate information about dimensions of physical features.
This is called land cover information. But Ground surveys are also required for attaining
greater accuracy in deciding the land use. Other kinds of remotely sensed data like aerial
photo can also be used for making land use map but its use and application is not
discussed in details

The output of work comes in the form of maps of land cover with a given level of
confidence about the results. They are not cent percent accurate because of lesser field
verifications but still they have a number of advantages over the manual land use
mapping.



   Practical Implementation in Town Planning

The research focuses at planning and development aspects of land. The idea is completely
applicable in context of Pakistan’s National, Provincial, Local Government and
Development Authorities.

The use of GIS has been appreciated by Capital Development Authority (CDA) and
Rawalpindi Development Authority (RDA). RDA has initiated using GIS for land use
mapping of its area of jurisdiction. Now days they are working to build land use
ownership database.

National Engineering Services of Pakistan (NESPAK) is one of the leading engineering
consultants of Pakistan. It has worked recently for Lahore Development Authority (LDA)
for calculation of areas under different housing schemes in Lahore using remote sensing
and GIS. NESPAK has used GIS in many other projects like Bhasha Dam Project. Such
kind of research is required so as to use and analyze the available modern techniques in
town planning profession.
SHORT METHODOLOGY

The research was conducted in the following broad steps.

Step 1: Background studies and concept building about the problem and GIS potentials

Step 2: Selection of The Case Study Area on the basis of satellite data availability

Step 3: Land use/ land cover mapping from satellite image using ArcView 3.2 GIS.

Step 4: Execution of ground surveys for determining accuracy level of the prepared land
use map.



TIME FRAME FOR THE PROJECT ACTIVITIES

The project followed stepwise procedure form problem identification to the final out put.
Assigning a specific time to each activity was very useful in this research. The time frame
for project activities helped us to assess our speed of work according to the available
time. The time frame of the project activities is given in the form of table below.



Table Time Frame For The Project Activities
PROJECT ACTIVITY                                     DURATION OF ACTIVITY

Background studies and concept building              8 weeks (June 2004 – july2004)

Data collection                                      4 weeks (August 2004)

Land use/ land cover mapping                         6 weeks (September – mid October)

Ground Truthing and determining accuracy level       2 weeks (2nd half of October)

Compilation of results in the form of land use
                                                     4 weeks (November 2004)
maps and other statistics
Existing Situation of GIS Use In Pakistan
In Pakistan, Geographic Information Systems (GIS) in not fully developed and practiced
for planning and decision making both at national to local level of Planning, in context of
urban and regional planning, environmental planning and resource management. The
major dominion which can be the focus of GIS operation for planning and research
include engineering universities, housing and physical planning departments,
environmental protection department, development authorities, local government and
rural development offices especially district councils, municipal corporations/
committees, semi-government agencies and private sector. Although some government
departments like soil survey of Pakistan and the forest department has started some
project on GIS but their area of application are quite isolated and are limited to their own
specific objective which are usually not share by other planning departments. In this
situation there is a need to set up some guidelines of common interest for the national,
provincial and local government agencies involved in planning and decision making
regarding the augmentation of GIS applications.

The increasing magnitude of operation of Geographic Information Systems (GIS) and its
applications to urban, regional and natural resource planning and management for
effective use is of utmost significance for planners and decision makers. In case of
Pakistan, GIS is not well practiced in the field of urban planning and resource
management and the degree of its usage is at different stages of development. The GIS
applications to planning and management are at the very infant stage in government
sector ranging from national to local level of planning agencies. Following this demand,
some strategies are proposed in this report which relate to the practice, expertise of GIS.