Going with the flow? Relative importance of riverine hydrologic connectivity versus tidal influence for spatial structure of genetic diversity and relatedness in a foundational submersed aquatic plant

Genetic connectivity in rivers is generally high and levels of genotypic and genetic diversity of riverine species are expected to accumulate in downstream locations. Genetic structure of marine and estuarine species is less predictable even though hydrologic connectivity is expected to be relatively high. These observations have been generated across different species and locations such that understanding effects hydrologic connectivity relative to tidal versus non-tidal environments in the same river remains incomplete. To control for species and location, we quantified diversity in 941 samples of Vallisneria americana Michx. (Hydrocharitaceae) collected from 36 sites along the species’ entire distribution in the tidal and non-tidal Potomac River of Maryland, Virginia, and the District of Columbia. Using ten microsatellite loci, we found 508 unique multilocus genotypes (MLGs), 36 of which were found multiple times across the riverscape, accounting for over 53% of the genotyped shoots...., Leaves were collected in the field and DNA was extracted.  Microsatellites were amplified using PCR and detected on an Applied Biosystems Incorporated 3730 DNA analyzer.  Microsatellite alleles were called using GeneMapper and checked manually for accuracy.  Multilocus genotypes were identified using the program Genodive and the poppr package in the R statistical environment as described in the publication., , # Genetic data for *Vallisneria americana* in the Potomac River, USA

[Access this dataset on Dryad](https://doi.org/10.5061/dryad.nvx0k6f17)

These data were used to understand the relative roles of hydrologic connectivity and tidal regime on the genetic diversity of *Vallisneria americana* in the Potomac River in Maryland, Washington, DC; and Virginia, USA collected in 2007, 2011, and 2013.

## Description of the data and file structure

The zip files all contain data folders that were used to complete the analyses for the manuscript titled, Going with the flow? Relative importance of riverine hydrologic connectivity versus tidal influence for spatial structure of genetic diversity & relatedness in a foundational submersed aquatic plant.

The files are needed for the R project Potomac.Manuscript.2024.RProject-v0.2 ([doi:10.5281/zenodo.14787930](doi:10.5281/zenodo.14787930)) to work. The zip files should be unzipped and the directories in those files should be placed at the top level o...,