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U radu je istraženo područje južnih obronaka Medvednice približne površine 100 km2 u kojem brojna klizišta predstavljaju prijetnju lokalnom stanovništvu i imovini. Dosadašnji inventari klizišta u ovom području su rađeni prema različitim kriterijima i za postojeće podatke nije rađena pouzdana analiza o brojnosti, rasporedu i veličini klizišta, ali i njihovoj aktivnosti. Zbog toga je ovdje korištena stereoskopska analiza stereomodela pomoću koje je prema istom kriteriju izvršena identifikacija klizišta i izrađen inventar klizišta za dvije generacije snimaka, iz 1964. i 1998. godine. Na taj način je ukupno identificirano preko 2.000 klizišta, a sve identificirane značajke klizišta upisane su u izrađenu bazu podataka. Provedena je i verifikacija rezultata istraživanja usporedbom s postojećim inventarima, izvještajima o klizištima, ali i terenskom provjerom. Identificirana klizišta su pomoću analitičkog hijerarhijskog procesa (AHP) klasificirana s obzirom na pouzdanost identifikacije i prema mogućnosti daljnjeg razvoja klizišta. AHP metoda je strukturirana tehnika pomoću koje su ovdje određeni težinski faktori i razrađen je sustav bodovanja, tj. bodovnih vrijednosti za svaku razmatranu alternativu pojedinog parametra. U radu se provela kalibracija takvog sustava bodovanja i izmjenili kriteriji poznati iz literature, kako bi bodovanje bilo prilagođeno istraživanom području. Rezultati istraživanja potvrđuju ranije podake o velikoj gustoći klizišta i njihovoj aktivnosti na istraživanom području, ali je njihova prosječna površina manja nego prosječne površine klizišta u postojećim inventarima. Također, iz rezultata istraživanja je vidljiv vrlo velik utjecaj erozijskog djelovanja vodotokova i antropogen utjecaj na stvaranje i razvoj klizišta. Analizom stereomodela iz obe generacije snimaka izrađena je karta relativne opasnosti od klizišta iz koje su vidljiva najugroženija područja. Značaj rada je i u mogućnosti primjene utvrđenih metoda i kriterija koji će omogućiti bržu i jeftiniju, ali pouzdanu izradu inventara klizišta i na područjima sličnih uvjeta., The term landslide comprises almost all varieties of mass movements on slopes. Landslide inventory contains data about landslides on certain area. Landslide inventory map shows the locations of the landslides and can contain other additional data and they are usually used in determination of landslide mitigation measures, civil engineering and urban planning. Spatial distribution of landslides and their activity is subject of change during time and that is a key reason for development of landslide inventory maps from different periods. Data in landslide inventory is one of the most basic and most needed in further analysis involving landslide susceptibility, landslide hazard and landslide risk. The area of the research covers approximately 100 km2 on the southern slopes of Mt. Medvednica. In that area there is a long history of landslides and there are multiple landslides which endanger properties and represent danger to local community. Existing landslide inventories of this area were developed by the usage of different criteria and for this existing landslide data a reliable analysis about their number, spatial setting, area and activity was never conducted. Because of this reasons stereoscopic analysis of landslides was conducted on two stereomodels from different periods (1964 and 1998). By the usage of the same criteria landslide identification on stereomodels were carried out and a landslide inventory was developed for each stereomodel. More than 2.000 landslides were identified and all identified landslide features and landslides were organized into a developed database. Also, most widespread and worldwide most commonly used method in landslide inventory development is stereoscopic analysis of stereomodel(s). Verification of the results was carried out by comparison with existing landslide data and by landslide field mapping. Identified landslides were classified by the usage of the analytic hierarchy process (AHP) according to the reliability of the landslides identification and according to the assessment of the possibilities of the further landslide development. Analytic hierarchy process (AHP) is a structural technique for data organization and analysis used for obtaining complex decisions. AHP can be also used practically in landslide mapping and assessment of characteristic landslide features. By AHP weight factors of landslide features were assessed and a scoring system was developed according to the weight factors (which was based on the visibility of the landslide features). Assessment of reliability of the identified landslides was based on the assessment of the visible landslide features on photography, which included: features in landslide body (accumulation and depletion) and visibility of the landslide border on the terrain surface. Also, the type of the land cover was taken into account. Assessment of possibilities of further landslide development was based on the assessment of the site topography, which included: slope inclination and assessment of the features at the landslide toe part. Also, type of the land cover was taken into account but a different criteria was used then for assessment of reliability for the identified landslides. Model calibration was carried out according to the features of the area of the research and landslide features in that area. Different scoring system was developed and used then existing ones in literature. Research results conforms the existing landslide data (landslide density and activity), but landslides identified by stereoscopic analysis in the area of research tends to have smaller areas than landslide areas in existing inventories (in accordance with literature). Also, the research results indicate the influence and the importance of the erosion processes and anthropogenic activities on the landslide activation and reactivation in the area of research. According to the reliability of the landslides identification and according to the assessment of the possibilities of the further landslide development an assessment of relative landslide danger was also carried out and a relative landslide danger map was developed from which the most endangered zones can be distinguished. The importance of the research is in the applicability of the used methods and developed criteria in the quicker, cheaper but accurate landslide inventory development everywhere where landslides exists in same or similar geomorphological conditions in Croatia or worldwide. Since there is no uniform landslide inventory for the whole territory of Croatia, the inventories presented here, the used methodology and the developed criteria also can be used as guidelines for the usage of remote sensing in landslide inventory development on national level.

The term landslide comprises almost all varieties of mass movements on slopes. Landslide inventory contains data about landslides on certain area. Landslide inventory map shows the locations of the landslides and can contain other additional data. Landslide maps can be prepared using different techniques. Landslide inventory maps are usually used in determination of landslide mitigation measures, civil engineering and urban planning. Spatial distribution of landslides and their activity is subject of change during time and that is a reason for development of landslide inventory maps from different periods (can be done by stereoscopic analysis of photographs from different periods). Data in landslide inventory is one of the most basic and most needed in further analysis in landslide susceptibility, landslide hazard and landslide risk. Most widespread and most used method in landslide inventory development is geomorphological mapping of terrain and usage of different methods of remote sensing (for example stereoscopic analysis). Even today, use and stereoscopic analysis of aerial photography has defined a prevailing standard and a benchmark against which new technologies to detect and map landslides are compared. Analytic hierarchy process (AHP) is a structural technique for data organization and analysis used for obtaining complex decisions. AHP can be used practically in landslide mapping and assessment of characteristic landslide features. Stereoscopic analysis was used in combination with AHP methodology for the assessment of characteristic landslide features on the southern slopes of the Mt. Medvednica. Assessment of characteristic landslide features for the identified landslides was based on the visible landslide features on photography (stereoscopic analysis), which included assessment of: landslide features (features at landslide body, features of landslide body boundary and features at main scarp) and features at landslide body toe part, slope morphology and land cover. Identified landslides were classified based on visible landslide features and according AHP score. Investigation encompassed: (i) criteria development for application of AHP methodology in area of research (100 km2), (ii) interpretation of 130 aerial photos of two generations, (iii) landslide inventory development and preparation of landslide inventory map and (iv) methodology verification on the basis of comparison with existing data and field check. In the paper some characteristic examples of identified landsides on the southern slopes of the Mt. Medvednica determined by stereoscopic analysis are given, with AHP score and field report. The methodology presented in this paper (stereoscopic analysis in combination with AHP methodology), is used for the first time in Croatia in landslide inventory development and preparation of landslide inventory map. Also the methodology and the established criteria is applicable in landslide inventory development and preparation of landslide inventory map in other areas where landslides exists in same or similar conditions, in Croatia or worldwide. Since there is no uniform landslide inventory for the whole territory of Croatia, the used methodology and the developed criteria also can be used as guidelines for the usage of remote sensing in landslide inventory development on national level.