A regional assessment of cumulative impact mapping on Mediterranean coralligenous outcrops
In the last decade, the ‘Cumulative Pressure and Impact Assessment’ (CPIA) approach emerged as a tool to map expected impacts on marine ecosystems. However, CPIA assumes a linear response of ecosystems to increasing level of cumulative pressure weighting sensitivity to diferent anthropogenic pressures through expert judgement. We applied CPIA to Mediterranean coralligenous outcrops over 1000km of the Italian coastline. Extensive feld surveys were conducted to assess the actual condition of coralligenous assemblages at varying levels of human pressure. As pressure increased, a clear shift from bioconstructors to turf-dominated assemblages was found. The linear model originally assumed for CPIA did not ft the actual relationship between expected cumulative impact versus assemblage degradation. A log-log model, instead, best ftted the data and predicted a diferent map of cumulative impact in the study area able to appreciate the whole range of impact scenarios. Hence, the relative importance of diferent drivers in explaining the observed pattern of degradation was not aligned with weights from the expert opinion. Such fndings stress the need for more incisive eforts to collect empirical evidence on ecosystem-specifc responses to human pressure in order to refne CPIA predictions.
Research funded by the project BIOMAP - BIOcostruzioni MArine in Puglia (Regione Puglia - Programma P.O FESR 2007/2013 - ASSE IV. Linea 4.4 - http://biomapping.it/index). Te European Union's Horizon 2020 research for the project MERCES (Grant agreement No. 689518, http://www.merces-project.eu) and the EU Interreg MED AMAre Project (http://msp-platform.eu/projects/amare-actions marine-protected-areas) are also acknowledged. We also thank Peter Mackelworth for the carefull revision of English language.
This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Te images or other third party material in this
article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.