Assessment of coastal vulnerability to land-based sources of pollution and its application in Apulia, Italy.

The present paper deals with the assessment of the coastal vulnerability to pollution sources induced by land-based activities (LBAs). The coastal vulnerability is expressed and evaluated in relation to the land-based activities present in the coastal areas and a new index, namely Coastal Pollution Index from land-based activities (CPI_LBAs), is proposed. The index is calculated considering nine indicators using a transect-based approach. The nine indicators refer to point and non-point sources of pollution, and include: rivers quality status, seaports category, airports category, wastewater treatment facilities/submarine outfalls, aquaculture/mariculture areas, pollution load of urban runoff, type of artisanal/industrial facilities, farm/agriculture areas, type of suburban roads. Each indicator is quantified by means of quantitative scores, whereas the strength of cause-effects relationship is assessed by assigning weights using the Fuzzy Analytic Hierarchy Process approach (F-AHP). The indicators are then aggregated to obtain a synthetic index and classified in five categories of vulnerability. The main findings of this study include: i) the identification of key indicators of coastal vulnerability to LABs; ii) the development of a new index to identify the coastal transects where the effects of the LBAs may be the greatest. The paper explains the methodology for the index computation, and illustrates it with an application in Apulia, Italy. The results demonstrate the feasibility of the index and its usefulness to identify the most critical areas in terms of land pollution sources and to produce a vulnerability map. The application allowed to have a synthetic picture of the threat of pollution from LBAs, facilitating its analysis and the benchmarking between the transects. Regarding the case study area, results show that low vulnerability transects are characterized by small agricultural areas/artisanal activities and small urban areas, whereas in very high vulnerability transects all indicators assume high scores.

Improvement of a coastal vulnerability index and its application along the Calabria Coastline, Italy.

The present paper further develops a coastal vulnerability index formulation (CVI) previously proposed by the authors by integrating a new variable and redefining three variables to improve the suitability of the index for low-lying coasts. Eleven variables are divided into three typological groups: geological, hydro-physical process and vegetation. The geological variables are: geomorphology, shoreline erosion/accretion rates, coastal slope, emerged beach width, and dune. The hydro-physical process group includes: river discharge, sea-level change, mean significant wave height and mean tide range. The vegetation variables are: vegetation behind the back-beach and coverage of Posidonia oceanica. The index was applied to a stretch of the Ionian coast in the province of Crotone in the Calabria region (Southern Italy), and a vulnerability map was produced. A geography information system (GIS) platform was used to better process the data. For the case study area, the most influential variables are shoreline erosion/accretion rates, coastal slope, emerged beach width, dune, vegetation behind the back-beach, and coverage of Posidonia oceanica. The most vulnerable transects are those near urban areas characterized by the absence of dunes and vegetation. Statistical and sensitivity analyses were performed, and the proposed CVI was compared with the previous formulation proposed by the authors and with two other CVI methods present in the literature.