Data from: Floristic and structural heterogeneity in a Neotropical riparian wetland: Conservation implications
Data files
Jan 17, 2025 version files 43.79 KB
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Jimeno_et_al_Database.xlsx
41.74 KB
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README.md
2.05 KB
Abstract
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.
README: Data from: Floristic and structural heterogeneity in a Neotropical riparian wetland: Conservation implications
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.