Coastal dune systems and disturbance factors: monitoring and analysis in central Italy

Abstract

This study describes the conservation status of dune systems in relation to disturbance factors in the coastal stretch of the Viterbo province, Latium Region, Italy. Particular emphasis was given to the bioindication value of plant communities and their sequence. Each plant community was considered as a "habitat" in accordance with Annex I of the Directive 92/43/EU. Stress factors, such as sand dynamic and erosion, and anthropogenic pressures, such as trampling and bathing settlements, influence the sequence of habitats and weaken the system of relations that makes these coenoses to occur in extreme conditions. The choice to carry out surveys along wide transects, recording different data, allowed to explore the use of habitats as bioindicators. Comparing sites characterized by the same extension in a homogeneous area, it was possible to expand the use of canonical correspondence analysis (CCA) as a tool to correlate habitat composition and disturbance factors. The application of CCA showed a high correlation of degradation and habitat loss with coastal erosion, trampling and presence of waste. Furthermore, floristic surveys allowed the application of different biodiversity indices to quantify species richness of sampled areas. The conservation status of the sites investigated was found to be diverse, from the total disappearance of the mobile dune habitats to their complete sequence. The proposed methodology has been useful to fulfill the objective of the work and is applicable to other case studies in the Mediterranean.

Shrub Encroachment Effects on Habitat Heterogeneity and Beetle Diversity in a Mediterranean Coastal Dune System

“…Conversely, anthropogenic disturbance and grazing are often cited as major contributors to desertification, land degradation and global biodiversity loss (Rutherford et al, 2014, but see Rowntree et al, 2004, and the introduction of excessive disturbance such as intensive grazing and trampling have reduced species richness of plants and arthropods in other coastal systems (Bonte & Hoffmann, 2005;De Luca et al, 2011;Santoro et al, 2012;Pedley et al, 2013;Ciccarelli, 2014). A shift to an entirely mobile dune landscape in NDNR would likely result in the loss of the unique species found on fixed dunes such as G. serrator Forskal.…”

Spatial application of Random Forest models for fine-scale coastal vegetation classification using object based analysis of aerial orthophoto and DEM data

“…Furthermore, the coastal habitat structures such as herbs, lichens, dwarf shrubs and other growth forms, are tightly linked to habitat function reflecting differences in edaphic conditions (Fenu et al, 2013;Hayden et al, 1991), topography (Moeslund et al, 2011), hydrology (Gedan et al, 2009) and natural disturbances (Brunbjerg et al, 2012;De Luca et al, 2011). The natural dynamics in coastal habitats are a prerequisite for the maintenance of their structure and biodiversity (Schirmel et al, 2011), but are regarded as threatened by eutrophication (Remke et al, 2009a,b), coastal protection (Defeo et al, 2009;Nordstrom et al, 2007), climate change (Miller et al, 2010), the introduction of invasive species (Callaway and Ridenour, 2004;Strayer et al, 2006) and decrease in extensive land use such as grazing (Buttenschøn, 2007;Provoost et al, 2011).…”

A methodological approach for assessing the effects of disturbance factors on the conservation status of Mediterranean coastal dune systems

“…H DUNE has proved to be more useful than the Shannon diversity index (Shannon & Weaver ) in extreme habitats such as the coastal dunes (De Luca et al. ), where natural stressful conditions determine the presence of a few species with high dominance (Martìnez et al. ).…”