Regional metacommunities in two coastal systems: spatial structure and drivers of plant assemblages

Abstract

Aim Biogeographical patterns in metacommunities are still poorly understood, and different processes are expected to occur in different habitats. We analysed the regional plant metacommunities of coastal habitats to test whether (1) the influence of space and climate differs between two habitats differentiated along the seashore-inland gradient, and (2) regional variation in species composition of these habitats can be ascribed to different metacommunity paradigms.Location The entire coast of the Iberian Peninsula, south-western Europe.Methods We collected data on the plant species composition of coastal sites on sand dunes across 3000 km of coastline. The sites were classified into two habitats corresponding to shifting and stable sand dunes, and divided into three distinct geographical regions: Cantabrian, Atlantic and Mediterranean. We assessed the geographical structure of the species composition using ordination, estimates of species turnover and spatial autocorrelation. We then used multivariate models and variation partitioning to test the influence of climatic and spatial effects. Analyses were conducted for the whole data set and the geographical subsets.Results Metacommunities from shifting and stable dunes showed similar spatial patterns, with the highest species turnover occurring in the Mediterranean region. Similarities between communities that were nearer each other (typically < 100 km) were weaker in shifting than in stable dunes, although the distance decay for sites that were further apart was similar in both habitats. Variation in species composition in shifting dunes was mainly explained by distance and climate, while in stable dunes the effect of climate was clearly dominant. The observed differences were relatively consistent across geographical regions.Main conclusions Distinct processes structure the metacommunities in two dune habitats differentiated along the seashore-inland gradient. Communities of shifting dunes seem to be structured by an interplay of neutral or patch-dynamic processes and to a lesser degree by species sorting. In contrast, communities of stable dunes are mainly governed by species sorting in response to climatic gradients. These results highlight the importance of differentiating habitats according to local ecological factors when analysing regional patterns in metacommunities.

Biogeographic variability of coastal perennial grasslands at the European scale

“…Artemisia campestris, Carex arenaria, Cerastium semidecandrum ), most of them show narrower geographic ranges and are related to specific climatic conditions or local biogeographic or geological histories (Piñeiro, Fuertes Aguilar, Draper, & Nieto Feliner, ). Our results are in line with those of Jiménez‐Alfaro, Marcenò, Guarino, and Chytrý () who found a greater effect of climatic variables on fixed dune communities with respect to shifting dunes.…”

Classification of European and Mediterranean coastal dune vegetation

“…These zones include the embryonic dunes, foredunes (shifting, also called white dunes), semi‐fixed dunes and fixed dunes (stable, also called grey dunes; Figure ). Effects of climate and spatial position on plant community structure differ between shifting and stable dunes (Jiménez‐Alfaro, Marcenò, Guarino, & Chytrý, ): embryonic and foredunes are more dynamic due to coastal winds and occasional inundation by sea storms, whereas beyond the foredunes, sand becomes more stable and ecological conditions are more benign. In the new classification of the European vegetation (Mucina et al., ; henceforth EuroVegChecklist: EVC), the plant communities colonizing shifting dunes are assigned to the pan‐European and pan‐Mediterranean phytosociological class of Ammophiletea , while those of stable dunes are largely assigned to the class Helichryso‐Crucianelletea maritimae .…”

Environmental filtering and dispersal as drivers of metacommunity composition: complex spider webs as habitat patches

“…Many studies have focused on elaborating these theoretical frameworks, while noting that these models are not mutually exclusive (Winegardner et al 2012, Meynard et al 2013. At the same time, an increasing number of empirical studies are currently testing assumptions associated with these paradigms (Cottenie et al 2003, Vanschoenwinkel et al 2007, Gu elat et al 2008, Logue et al 2011, Jimenez-Alfaro et al 2015, Zheng et al 2015, Grainger and Gilbert 2016.…”