DOI: 10.5061/dryad.5tb2rbpdq
title: Data from: Floristic and structural heterogeneity in a Neotropical riparian wetland: Conservation implications

description: Despite the incontrovertible importance of wetland ecosystems, our
 understanding of the causes underlying the spatial heterogeneity of their
 attributes is still insufficient. Here, we assess the spatial variation of
 the floristics (species composition and their relative abundances) and
 quantitative structure (vegetation cover) of the San Pedro Mártir River
 riparian herbaceous wetlands (Tabasco, Mexico), and explore potential
 factors responsible for within- and among community variation. Vegetation
 was sampled at 10 sites along a 40-km stretch of the river. Per site cover
 of the recorded morphospecies was assessed with digital photography, and
 community diversity was analyzed using the Hill numbers framework. Total
 richness was 76 morphospecies (67 identified to some taxonomic category);
 the drastic decrease in true diversity with increasing q values indicated
 that few species dominate the community matrix, while numerous remaining
 species occupy the small interstices among them. Three Cyperaceae species
 had the largest importance in the community, with Cladium jamaicense being
 the most frequent and having the largest cover along the river. Ward’s
 site classification and NMDS ordination indicated the existence of four
 floristically and structurally different vegetation groups. Within sites,
 GLMMs showed a weak inverse relationship between species richness and
 distance from the river, but no relationship for plant cover. Fluvial
 geomorphology, and possibly regional geological heterogeneity, are the
 main factors determining the spatial variation of these herbaceous
 wetlands. Deep understanding of the relationship of herbaceous riparian
 wetlands with their environment will improve the prediction of the effects
 of modifications of fluvial dynamics and support efficient conservation
 strategies.
description: # Data from: Floristic and structural heterogeneity in a Neotropical
 riparian wetland: Conservation implications
 [https://doi.org/10.5061/dryad.5tb2rbpdq](https://doi.org/10.5061/dryad.5tb2rbpdq) ## Description of the data and file structure The data were collected at ten sites of herbaceous riparian wetland along a 40 km stretch of the San Pedro Mártir River. At most sites but one (where sampling effort was half that in all other sites), vegetation was sampled in ten 4 m2 quadrats located at various distances from the river edge. At the center of each plot, we took five to eight photographs to assess the cover of each species. We used a 20-megapixel *Evorok Adventure III* camera with a wide-angle lens mounted on a support fixed to an L-shaped structure; the camera was kept at a height of 3 m above the vegetation. Additionally, the cover of some species was visually estimated and recorded in the field. In the laboratory, the photographs taken in the field were corrected using *Adobe Photoshop CC 2018* to reduce the spherical distortion produced by the wide-angle lens. To estimate the cover of each morphospecies, the images were divided into four equal sections to facilitate the use of the Ordinal Transfer Value (OTV), a modification to the nine-value ordinal scale proposed by van der Maarel (2005), which uses the mean value of the extremes of each cover interval. The percent cover of each plant was transformed into cover values expressed in area (m2).  ### Files and variables #### File: Jimeno\_et\_al\_Database.xlsx **Description:** The database is an Excel book with three pages. The first page has contact information. The second page has the metadata. The third page has the variables.  ##### Variables * Column A (Site): Site identifier (e.g., Site 1, Site 2, etc.). * Column B (Plot): Plot number. * Column C (Distance): Position of the plot along the transect (in meters from river edge). * Columns C to CA (Morphospecies): Plant (morpho)species with their cover values (m²) ​​in each sampled plot.