Search

International audience; Plant-associated nematode species are supposed to cause marram grass (Amrnophila arenaria) decline in foredunes. But experiments with inoculated species populations have not proven any nematode effect on plant die out. Considering that nematode community patterns (ecological approach) would be more effective on plant growth than emblematic species (agronomical approach), a large survey in North (Belgium, France, The Netherlands, UK) and South (Portugal) European and in North African (Morocco) foredunes was conducted in order to analyse the diversity of the plant-associated nematode communities. It indicated that diversity (population levels, richness, diversity, evenness, trophic and colonizer/persister groups) does not differ between the communities sampled. But, the nematode community patterns are significantly impacted by climate and soil factors. Root-knot (Meloidogyne spp.) and lesion (Pratylenchus spp.) nematodes were more represented in Atlantic than in Mediterranean nematode communities, whereas cyst nematodes (Heterodera spp.) were more abundant in Northern than in Southern Atlantic nematode communities. Within the French nematode communities, the Atlantic communities strongly differ from the Mediterranean communities. It could be hypothesized that the sediment origin of the foredunes (e.g. Massif Central and Pyrenees for Atlantic sites vs Alps for Mediterranean sites) may be involved, because one Mediterranean site that showed an intermediate pattern is concerned by sediments from Massif Central origin. Knowledge about plant-associated nematode community structures in marram grass foredune ecosystems would help landscape managers for dune stabilization with plants. (C) 2011 Elsevier B.V. All rights reserved.

WOS: 000297037500008 This study aimed to provide an assessment of coastal sand dune vegetation through a number of analyses meant to provide a better understanding of the structure of plant communities and the successional stages of coastal sand dunes in a human-induced coastal landscape, the Seyhan Delta in southern Turkey. Therefore, as a baseline data inventory for monitoring, succession and the community-based classification of sand dune vegetation and human impacts were the major concerns of this study. The zonation of coastal sand dune vegetation was also determined within this scope, providing a contemporary assessment of different successional stages. A total of 96 taxa were recorded in 103 sampling releves, which were randomly placed along 2 replicated transects perpendicular to the coastline. Multivariate classification techniques (TWINSPAN and DECORANA) were employed to classify sand dune vegetation into groups corresponding to different successional stages and to determine the response of plant community structures to human influence. Multivariate analysis resulted in a clear demonstration of 7 floristically distinct community groups associated with 4 main geomorphologic units. These plant communities were matched to the European Nature Information System (EUNIS) habitat classification. The results of this study provided a baseline data inventory covering plant communities and successional stages that demonstrated the current state of the coastal dunes in the study area. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TBAG-1793] The authors wish to acknowledge the partial support of the Scientific and Technological Research Council of Turkey (TUBITAK) under research project TBAG-1793.