G.I.S. context analysis for environmental recovery suitability evaluation

Abstract

The attributes of every single patch in a land mosaic constitute the database that landscape ecologists use for processing and analysis. Nonetheless spatial and ecological relationships between adjacent patches can play a key role in understanding the overall functionality of land mosaics. Defining the ecological role of a single tessera within an ecosystem is not possible if that patch is regarded as an insular element; on the other hand global analysis on the entire land mosaic would grant just a small amount of new information on each tessera and none on its functional role. To recognize areas susceptible of improvement through environmental recovery and to define priorities for intervention within a given territory it is necessary to identify low naturalness systems adjacent to preserved areas. To accomplish this task a specific land mosaic analysis tool has been created within a G.I.S. environment: it is designed to identify, within the high naturalness area choosen as a case study (the Monti Madonie Regional Park), the location where environmental recovery would be most effective. Available data on vegetation are processed through a context analysis based on the comparison of the Index of Landscape Conservation. Numeric values resulting were divided into three classes of effectiveness which represent in which measure an environmental recovery intervention would be effective in improving naturalness and landscape conservation. 33 of the 42 land systems are in the lowest class, meaning that intervention would be of little or non interest. These systems are located in the core area of the Park and are already intact and close to other high naturalness areas. On the other hand, some systems in this class are peripheral and even in this case intervention would be useless, since these systems already suffer a strong human impact and are adjacent to low naturalness areas. 8 of the 42 land systems are in the intermediate class. These are mainly “buffer” systems located between high naturalness areas and the territory surrounding the park. The algorithm assigned the highest value to one of the 42 land systems. Two quarries and a small portion of a third are located in this area that is adjacent to Quacella, one of the most important biodiversity hotspots of Sicily. The tool prooved to be capable of identifying precisely a degraded portion of terrritory adjacent to one of the most intact (and rich from a biologic point of view) areas of the Park.