Abstract: Based on MapObjects(MO),the software of the component object model (COM) geographic information system (GIS),site decision support model (SDSM) was shown in this paper. As a result,the spatial information and attributive information were synthetically managed,such as digital elevation model,digital terrain model,soil distribution model,forest distribution model and so on. It was aimed at classification of site type in afforestation planning and designing in forestry centre. The elementary unit is subcompartment,and so site type of subcompartment is operated by SDSM. The model was composed of site district decision support model and site type decision support model. Spatial analysis module,in the form of SSQL (spatial standard query language was applied) in MO,was operated to the knowledge base of site type based site factor and of site district based regionalism,so that the site type of afforestation subcompartment can be automatically afforded.

Key words: component object model(COM) geographic information system(GIS), site decision support model(SDSM), afforestation subcompartment, spatial analysis, automatic decision