Forests are an important natural resource in many parts of the world and provide the raw material for a wide range of wood - based industries. They are also important for regulating water supply, controlling erosion, protecting wildlife and for outdoor recreation.

Forest management is concerned with ensuring a sustainable supply of timber and other products, and all other forest related uses while taking account of ecological considerations. The preparation, control and execution of a forest management plan requires a wide range of information, much of which is geographically referred.

The spatial information required for the management of forest land includes a wide range of natural and artificial features which must be considered in planning and executing forestry operations (Table 1).

The conventional methods of collecting the above information are from Survey of India (SOI) topographical maps, departmental records and field survey.

The information collected form departmental records are outdated since they are collected primarily by field workers and then compiled manually. It therefore takes a couple of years before this information is compiled properly, published and available for use.

Even so, all the information may not be available for some area. For example, details about soil quality may not be available for particular area at the district level since no soil survey was conducted at that site.

Once all the required (and available) data is collected, it is to be compiled in the form of a map. To start with, a base map (topographical map) on a suitable scale has to be prepared and then the requisite information is transferred on it. This has the following limitations:

A reliable and timely database is thus a pre-requisite for effective forest management, which can be achieved by using modern information technology like remote sensing and GIS.

Table 1: Typical spatial information requirements for forest management

Information Category		Purpose
Administrative boundaries		General administration, management and planning
q	cadastral boundaries
q	forest administration boundaries
q	timber concession boundaries
Terrain features		Planning of timber harvesting (eg. road construction site assessment (e.g. susceptibility to windthrow)
q	elevation
q	slope
q	aspect
q	drainage
Infrastructure		Planning and management of forest operations
q	roads, tracks, etc
q	power lines, pipelines, etc.
q	buildings and other structures
Soil and understory vegetation		Site assessment and silvicultural treatment
Forest stand characteristics		Planning and management of forest operations (thinning, harvesting)
q	species composition
q	age
q	yield class
q	density
Management activities
q	realized and planned silvicultrual treatment (thinning, harvesting, etc.)
q	land use zoning (eg. nature protection)
q	fire control
q	damage control (eg. insects, wind)

The Geographic Information System also obtain its data from the usual source: SOI topographical maps, departmental records plus satellite imagery. The key is that data manipulation is done on the computer rather than manually. The procedure followed in preparing a plan is similar to the conventional method: the base map is registered on the computer using a digitizer. The rest of the information is then entered onto this base map. The use of computers speeds up the map making process and is also more accurate.

India began to use the GIS technology about four to five years ago. Successful application of this technology depends upon well trained staff and an appropriate operational environment.

During the last decade, there has been considerable interest in the potential use of GIS to support forest management. This trend has been most noticeable in Canada and United States, where every major forest management agency has acquired, or proposes to do so, the GIS capability.

The potential uses of GIS to support forest management are considerable. The production and revision of maps and accurate determination of the area are important tasks in forest management. In North America, GIS is being used by forest management agencies for

Recently, forest management agencies in many developing countries especially the timber producing nations in Southeast Asia (Indonesia, Malaysia and Thailand)have started using GIS technology. q