STRUCTURE OF METADATA IN GIS * 
Eva-Maria Förster, Regine Hang 
GSF-Forschungszentrum für Umwelt und Gesundheit, Postfach 1129 
D-85758 Oberschleißheim 
Armin Müller 
Technische Universität München, Lehrstuhl für Landschaftsökologie 
D-85350 Freising 
Roman Lenz 
Fachhochschule Nürtingen, Fachbereich Landespflege, Schelmenvasen 4-8 
D-77662 Nürtingen 
ABSTRACT 
This paper describes the metadata information system for geometric data and maps within the 
interdisciplinary research project FAM (Forschungsverbund Agrarökosysteme München). The 
tool is based on the FGDC-standard and programmed within the GIS Arc/Info with the macro 
language AML. The information system assists not only in storing, but also in retrieving spatial 
information and information on existing maps. Scientists working on other topics in subprojects 
can use the tool to decide whether the data is suitable for their own purpose and whether they 
can be used as basis of further evaluation 
The metadata for the experimental results (e.g. the sampling method, chemical analysis, statisti 
cal calculations, name of the responsible scientist) are stored in the FAM database, an ingres 
database management system. These are raw data which have no spatial information except the 
sampling point within the study area. In GIS there are three different kind of metadata which 
must be distinguished: metadata concerning the raw geometry, the manipulated geometry and 
the map geometry including related attributes. 
Additional to general information like goal, responsible scientist, validity, time and spatial scale 
range, information about the geometry (point, lines, polygons), e.g. the sources of the data, the 
resolution, quality and positional accuracy are stored. This is true for the original data and the 
manipulated data as result of GIS functions like buffering, intersecting, clipping, etc. The de 
rived attributes must be documented as well. 
While visualizing those derived data in a map, the metadata of the used layers (coverages, grids, 
tins, images) must be accessible and additional information concerning the ‘mapping con 
straints’, e.g. generalisation, readability and purpose must be stored. * 
* Presented at the International Society for Photogrammetry and Remote Sensing ‘Workshop on New 
Developments in Geographic Information Systems’, Milan, Italy, 6-8 March 1996