An integrated, GIS-based, object-oriented, multi-scale geomorphological mapping system, capable to fulfill all of the practical needs of the modern society is here presented. The increasing variety of multipurpose, applied land projects (geomorphology for land planning and risk mitigation, landscape ecology, hydrology, geoarchaeology, etc.) requires, in fact, a full representation of the spatial properties of landforms, reducing the use of symbols in favor of correctly bounded geometric elements (full coverage mapping). Moreover, the extremely wide range of landform sizes requires new mapping systems able to represent the same area at different space-temporal scales. Full coverage object-oriented mapping may be performed by progressive expert judgment-based inter-comparison between “traditional” field mapping and grid- or object-oriented analysis from automatic landform recognition. Object-oriented analysis, based on grid segmentation, allows partitioning DEMs or remotely sensed images into non-overlapping regions (segments), representative of geomorphic entities. Following the above principles, a new GISbased, full coverage, object-oriented, multi-scale geomorphological mapping system (GmIS_UNISA) has been built-up at the Department of Civil Engineering of the Salerno University (Italy) and CUGRI (inter- University Consortium for Great Risk Prevision and Prevention, Salerno-Naples, Italy). The informative data structure of the different taxonomic levels is organized in terms of “full-coverage, nested topologic objects”, as multilevel arc-node spatial data structure, supported by an analogous hierarchical attribute list. Levels 1 (physiographic domain), 2 (physiographic region) and 3 (physiographic province) correspond to distinctive land features, respectively significant at the continental, subcontinental and regional scales. Level 4 (morphological system) includes prominent landscape components such as plateaus, valleys, plains, and coastal belts. Level 5 (morphological sub-system) includes mid-size landscape components such as small ridges, hillslopes, valley floors, and piedmonts. Level 6 (morphological pattern) includes large compound landforms (e.g., alluvial terraces, glacial cirques, coastal cliffs, and talus belts). Levels 7, 8, and 9 are essentially based on detailed field survey and monitoring. The identification/delimitation criteria imply the definition of detailed landform topoposition, morphometry and morphogenetic consistency, acquired by automatic landform recognition from fine DEMs (10x10 m to 5x5 m) and the interpretation of large scale air photos. Level 7 (landform complex) includes mid-size landforms produced by single or multiple geomorphic processes (e.g. large river channels, coastal arcs, large compound landslides). Level 8 (landform unit) includes small landforms (e.g. alluvial terrace scarp, moraine arcs, mid-size landslides) or landform components (e.g. terrace scarp slide, coastal cliff notch, landslide scar). Level 9 (landform element) includes non-decomposable landforms with reference to the project purposes. Level 8 usually represents the starting point (focal level) for the production of lower-level maps by nested landform composition.
From geomorphological mapping to geomorphological map modeling: a new GIS based, object-oriented, multi-scale mapping system
GUIDA, Domenico;
2011-01-01
Abstract
An integrated, GIS-based, object-oriented, multi-scale geomorphological mapping system, capable to fulfill all of the practical needs of the modern society is here presented. The increasing variety of multipurpose, applied land projects (geomorphology for land planning and risk mitigation, landscape ecology, hydrology, geoarchaeology, etc.) requires, in fact, a full representation of the spatial properties of landforms, reducing the use of symbols in favor of correctly bounded geometric elements (full coverage mapping). Moreover, the extremely wide range of landform sizes requires new mapping systems able to represent the same area at different space-temporal scales. Full coverage object-oriented mapping may be performed by progressive expert judgment-based inter-comparison between “traditional” field mapping and grid- or object-oriented analysis from automatic landform recognition. Object-oriented analysis, based on grid segmentation, allows partitioning DEMs or remotely sensed images into non-overlapping regions (segments), representative of geomorphic entities. Following the above principles, a new GISbased, full coverage, object-oriented, multi-scale geomorphological mapping system (GmIS_UNISA) has been built-up at the Department of Civil Engineering of the Salerno University (Italy) and CUGRI (inter- University Consortium for Great Risk Prevision and Prevention, Salerno-Naples, Italy). The informative data structure of the different taxonomic levels is organized in terms of “full-coverage, nested topologic objects”, as multilevel arc-node spatial data structure, supported by an analogous hierarchical attribute list. Levels 1 (physiographic domain), 2 (physiographic region) and 3 (physiographic province) correspond to distinctive land features, respectively significant at the continental, subcontinental and regional scales. Level 4 (morphological system) includes prominent landscape components such as plateaus, valleys, plains, and coastal belts. Level 5 (morphological sub-system) includes mid-size landscape components such as small ridges, hillslopes, valley floors, and piedmonts. Level 6 (morphological pattern) includes large compound landforms (e.g., alluvial terraces, glacial cirques, coastal cliffs, and talus belts). Levels 7, 8, and 9 are essentially based on detailed field survey and monitoring. The identification/delimitation criteria imply the definition of detailed landform topoposition, morphometry and morphogenetic consistency, acquired by automatic landform recognition from fine DEMs (10x10 m to 5x5 m) and the interpretation of large scale air photos. Level 7 (landform complex) includes mid-size landforms produced by single or multiple geomorphic processes (e.g. large river channels, coastal arcs, large compound landslides). Level 8 (landform unit) includes small landforms (e.g. alluvial terrace scarp, moraine arcs, mid-size landslides) or landform components (e.g. terrace scarp slide, coastal cliff notch, landslide scar). Level 9 (landform element) includes non-decomposable landforms with reference to the project purposes. Level 8 usually represents the starting point (focal level) for the production of lower-level maps by nested landform composition.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
