An information system for vegetation management
MUÑOZ J.M., SÁNCHEZ A., PORRAS R., QUIJADA J. & MOREIRA J.M.
Department of Plant Biology, University
of Córdoba, Campus de Rabanales, Colonia de San José nº 4, Córdoba, Spain
Andalusia (Spain), has a total surface area of 8,760,000 ha., similar to that of countries such as Portugal and Belgium. Forest surface accounts for 53% of this area. Around 30% of the area is currently under some form of legal protection, e.g. as a National Park, Natural Park, or other designated area. In the 1980’s, when environmental management was taken over by the Andalusian Regional Government, a programme was set up to collect and coordinate information concerning the environment and the natural resources of the region, with a view to optimizing resource management. Within this programme, it was decided that environmental mapping information should be generated in protected natural areas (PNA), using new GIS and remote sensor technology whose utilization is becoming increasingly widespread and whose features and advantages for environmental management are evident.
The vegetation map was one of several thematic maps embarked upon. PNA vegetation was mapped at a scale of 1:10.000, and methods were developed to enable all data generated to be included in a geographic information system (GIS).
The methodology used comprises three major phases:
1. Photointerpretation using aerial photographs in false infrared color at a scale of 1:15.000/1:20.000. The scale and type of photograph enables recognition and differentiation of the major types of vegetation structure: woodland formations, preforest shrubland, low shrubland and grassland. Physiognomic-structural criteria are therefore used for differentiation.
2. Field sample collection. Three sampling methods were used: two random (linear transects in woody communities and squares for grassland) and one directed (inventory, in natural or seminatural communities).
3. Restitution and coding. This entails creation of a digital polygonal cover using GIS software, and of orthophotographs at a scale of 1:10.000, in order to correct deformations inherent in aerial photography. For subsequent coding, each polygon distinguished in the graphic cover is assigned a code, which is associated to information that will enable generation of different types of graphic output, according to the manager’s requirements.
The material generated by this process essentially comprises:
I. Databases, in DBase IV or Access format.
II. Graphic cover in digital format, Arc-Info.
This information can be used to generate different types of graphic output and to obtain quantitative data relating to the various types of vegetation in the study area.
All mapping, database and documentary information is standardized and included in an Environmental Information System which houses data on soil, climate, water and other aspects, using criteria similar to those used for vegetation; this helps to enhance analysis of natural resources over the whole area.