seascape genetic analysis reveals strong biogeographical structuring driven by contrasting processes in the polyploid saltmarsh species Puccinellia maritima and Triglochin maritima

• Published in: Molecular ecology Vol. 23; no. 13; pp. 3158 - 3170
• Main Authors: Rouger, R, Jump, A. S
• Format: Journal Article
• Language: English
• Published: England Blackwell Science 01-07-2014; Blackwell Publishing Ltd
• Subjects: Alismatales - genetics; Biogeography; Community ecology; conservation plants; Discriminant Analysis; discriminant analysis of principal components; DNA, Plant - genetics; Ecosystem; ecosystems; Environmental restoration; genetic techniques and protocols; Genetics; Genetics, Population; imports; isolation by resistance; Microsatellite Repeats; Models, Genetic; Plant ecology; Poaceae - genetics; Polyploidy; population structure; Principal Component Analysis; Puccinellia; Puccinellia maritima; salt marshes; Salt-Tolerant Plants - genetics; saltmarsh; sediment transport; Triglochin maritima; United Kingdom; Wetlands; United Kingdom; Puccinellia maritima; Triglochin maritima; polyploidy; saltmarsh; discriminant analysis of principal components; isolation by resistance
• ISSN: 0962-1083; 1365-294X
• DOI: 10.1111/mec.12802

Little is known about the processes shaping population structure in saltmarshes. It is expected that the sea should act as a powerful agent of dispersal. Yet, in contrast, import of external propagules into a saltmarsh is thought to be small. To determine the level of connectivity between saltmarsh ecosystems at a macro‐geographical scale, we characterized and compared the population structure of two polyploid saltmarsh species, Puccinellia maritima and Triglochin maritima based on a seascape genetics approach. A discriminant analysis of principal components highlighted a genetic structure for both species arranged according to a regional pattern. Subsequent analysis based on isolation‐by‐distance and isolation‐by‐resistance frameworks indicated a strong role of coastal sediment transport processes in delimiting regional structure in P. maritima, while additional overland propagule dispersal was indicated for T. maritima. The identification and comparison of regional genetic structure and likely determining factors presented here allows us to understand the biogeographical units along the UK coast, between which barriers to connectivity occur not only at the species level but at the ecosystem scale. This information is valuable in plant conservation and community ecology and in the management and restoration of saltmarsh ecosystems.