productivity, to save time, money and mon power
(Altan, Toz, Can, Tastan 1991)
4- 2- Importance of a GIS
In general, the term data corresponds to descrete,
recorded facts about phenomena from which people
gain information about the real world. In
context of geography, data may be considered,
as data about geographic features such as roads,
buildings, rivers etc, and phenomena, such as
weather forecast, earthquackes, etc.Conventional
maps provide a very effective graphic informati-
on of the geographic features, but they are not
very useful for supporting data retrival. Data
retrival on these maps is usually done by visual
search, a process that is neither efficient
nor reliable. Spatial analysis is even more d.if-
ficult. Even for simple application such as
calculation the total area of the clearing in
a forest, the amount of manual work involved is
sometimes prohibitive.
4- 3- Sources of a GIS
The sources of a GIS may be (Tastan, 1991)
- Conventional maps
- Ürthophoto-and photo maps
- digital maps
- aerial photos
- satellite images
- video images
- land observations
- cadastral records
-computer aided drawings
- database files
- text files
4- 4- Requirements of a GIS
A GIS is supposed to satisfy the following main
requirements (Rondeux, 1991)
- ability to handle multilayered, heterogeneous
data bases of spatialy-indexed data,
- ability to query the data bases about the
location and properties of a range of spatial
objects,
- efficiency in managing such as queries in an
interactive mode,
-ability not to retrieve but also to create
new information,
-flexibility in :configuring the system in
order to accomodate a variety of specific
applications.
4- 5- Definition of forest Management
Forest management is the design and implementation
of a set of actions in which stands are harvested,
products are distributed, cutovers are renewed,
and protection against insects, fire and disease
is provided (Baskerville, 1986)
These activities are controlled in timing, amount
and geographic space so that their cumulative
effect generates a desired mix of benefits such
as timber, recreation opportunity, etc. from
the whole forest over time. The main objectives
of the forest management are to
- find one schedule, i.e., design, that
appears likely to produce the desired future
forest development pattern and flow of benefits,
- implement that schedui] year-by-year,
-monitor forest performance periodicalyy to look
for and remedy divergence between expected and
actual outcomes (Jordan, Erdle, 1989)
4- 6- Application of GIS in forest management
In forest management activities, locational
and descripte data as well as the relationships-
between themare required. All of these data and
relationships can be regarded as geographical
714
information which are subjected to change dinami-
caly. Traditionaly, locational data consist of
covertype maps which define the location of all the
forest's components such as series, compartments,
working circles, felling blocks, sites, stands,
utilization, classes, age classes and topography,
as well; whereas descriptive data are composed of
conventional inventory data which describe the
physical conditions of these components such as
the annual grawing stock and increment in a
working circle, tree species in a stand class, etc.
Neither conventional maps nor forest inventories
are sufficient enough to supply locational and
descriptive forest data. Updating of these maps
and inventories is rother cumbersome and time
consuming. Although some CAD ana DBM systems are
able to manupulate these type of data and solve
problems to some extent, the relationship between
these two different types of data can not be
created. A GIS applicated in forest management
seems to be an obvious choice, for it is able
to manupulate locational and descriple data and
the relationships between them, as well; even
dynamicaly.
Contrary to common public perception, forest
managment involves much more than harvesting and
planting trees. Forecasting is a key ingredient
in forest management design; cust effective lin-
king (over time and geographic space) of interven-
tions is a key concern in forest management
implementation; an accurate up-to-date log of
stand intervention and growth responses is
essential in monitoring cumulative forest
performance. All. require an up-to-date accurate
present forest inventory. Ît is in these four
aspects of forest management - inventory, design,
implementation and monitoring - that GIS has the
most to contribute. (Jordan, Erdle 1989) On the
other hand the following main objectives of a
GIS for Forest Management can not be overemp-
hasized:
-to provide a geometric frame of reference,
-to document locational, qualitative and quantita-
tive distributions of trees,
-to document all infrastructure for management
and harvest (access roads, etc.) (Strobl, 1992)
2- Forest management Information system (FORMIS)
as an application of GIS in the forestry in Turkey
FORMIS is a GIS application software for Forest
Management activitites. It's written in simple
macro language (SML) of the GIS software package
PC ARC/INFO. FORMIS geographic data base consists
of both locational data (manually digitized
covertype maps of the forest serie Büyükdüz in
Turkey) and related inventory data.
The FORMIS project has been organized into a series
of logical steps, each of which builds upon the
previous one as defined in the reference (ESRI,
1990) The first step was to build the database.
At this step, the database was designed, locati-
onal data were input using a manual digitizer and
editted, topology was created, descriptive data
were input and finally some transformations were
performed. While designing the database, determined
was Forest serie as the study area and Gauss-Krüger
coordinate system as the reference system. Geograp-
hic features, their d escriptrive data (attiribu-
tes) and data layers required were identified as
follow:
- compartments
- working circles
- felling btocks
- site classes
O cr zx q Q O O cr) -4O -5c* -50 OO OT =) = =n \N pi (D
Qc "E> D OT TT =—
-~ D0 Q. cC
1] A a uP pn YY OR | 0) 1. Os Hj "T| >
