Mapping forest landscape change in Iezer Mountains, Romanian Carpathians. AGIS approach based on cartographic heritage, forestry data and remote sensing imagery

This paper focuses on one of the representative areas of the Southern Carpathians, the Iezer Mountains (2470 m a.s.l.), specifically the Rausor catchment which has integrated digital data from various available sources in order to map the evolution of forested area limits and features. The timberline was reconstructed on the basis of large scale maps from 1791, 1856, 1904, 1982 and 1996 (the latest forest cadastre map), as well as from Landsat imagery (1987 and 2002) and ortophotos (2005). The GIS visualization and mapping of the entire Iezer Mountains area allowed the drawing of a synthetic map of the altitudinal vegetation zones, combined with windthrow occurrence areas. The main feature is that the anthropogenic transformation of the timberline configuration was strongly influenced by grazing. This intensified particularly during the 19th and the first half of the 20th centuries. Shepherd huts and footpath configuration offered a good explanation for the directions of forest spatial pattern changes. Together with the data derived from the old maps (of the 19th century) the forestry data can explain windthrow affected areas as well as the windthrow susceptibility pattern. The windthrow occurrence areas were compared to the results of a separate GIS windthrow susceptibility analysis and validated by orthophoto interpretation and field GPS survey (4-5 m accuracy).