Temporal and spatial changes in plant dune diversity in urban resorts

Abstract

We investigated the temporal and spatial changes in the floristic composition and abundance in sand dunes along a coastal strip in the province of Buenos Aires (Argentina). Firstly, we analysed changes over a span of 70 years, comparing 41 of our own inventories carried out in 14 beach resorts in 2005-2006 with 18 inventories made in the first half of the XXth century (1930)(1931)(1932)(1933)(1934)(1935)(1936)(1937)(1938)(1939)(1940) in the same study area. We grouped sampled plots into four categories for comparison, taking into account the time period (1930-1940 or 2005-2006) and location at each end of the surveyed coastal strip in the northern or southern 'tourist' sectors. Secondly, we analysed the effect of afforestation with exotic trees on extant sand dune vegetation for the period 2005-2006. A total of 74 plant inventories were carried out in afforested and natural dunes at the same resorts. In both comparisons we contrasted plant richness, percentage plant cover, similarity and diversity. A cluster analysis was used to classify categories taking into account plant abundance and composition. Significant differences in total diversity were observed between sampling years, suggesting an increase in diversity at the present time due to urbanization and recreation related activities. Nevertheless, no single exotic plant species was clearly dominant across the sampled sites, suggesting that these coastal areas are, up to now, resistant to alien invasion. Diversity indexes discriminated by plant groups indicating different habitat conditions and exotics were shown to be more sensitive to existing changes than to total richness and cover.

Diachronic analysis (1954–2010) of transformations of the dune habitat in a stretch of the Northern Tyrrhenian Coast (Italy)

“…In all cases, coenosis are more reduced, in comparison with the surrounding areas, by the floristic point of view (Arrigoni 1990;Sani & Tomei 2006;Bertacchi et al 2009). (C) In literature, the development and application of multiple systems of indexing of the distribution of plant communities and floristic diversity of these environments is known (Frederiksen et al 2006;Grunewald & Shubet 2007;Acosta et al 2009;Carboni et al 2009;Faggi & Dadon 2011). In this case, the indexing tool is very Géhu et al (1984).…”

Multiscale Burrow Site Selection of Gopher Tortoises (Gopherus polyphemus) in Coastal Sand Dune Habitat

“…However, conflicts among conservation of coastal natural resources, land development, and sustainability of economic activities have been increasing substantially since the mid-20th century (Faggi and Dadon, 2011). The coastal sand dunes of Georgia and Florida are home to some of the most iconic and charismatic wildlife species of the SE United States, such as eastern diamondback rattlesnakes (Crotalus adamanteus), gopher tortoises (Gopherus polyphemus), and myriad shorebirds.…”

The “ReDune” index (Restoration of coastal Dunes Index) to assess the need and viability of coastal dune restoration

“…Due to their high vulnerability Nordstrom, 2008), sandy beaches and coastal dunes are among the ecosystems likely to be most threatened and damaged (Barbier et al, 2011;Ketchum, 1972;Nordstrom, 2008). Typically, human-related impacts on coastal dunes alter natural dynamics and processes; eliminate topographic variability; fragment, degrade or eliminate habitats; affect biodiversity (by increasing, decreasing or substituting species) (De Luca et al, 2011;Faggi and Dadon, 2011;Martínez et al, 2006Martínez et al, , 2013bNordstrom, 2000) and disrupt the provision of ecosystem services (MendozaGonzález et al, 2012). As a result, actions of restoration on coastal dunes are increasingly necessary.…”