Environmental Factors Influencing Species Richness Expression in Grasslands of the Colombian Orinoquia.

The relationships between environmental characteristics and species richness in the grasslands of the Colombian Orinoquia are presented and analyzed using an ordinal logistic regression model. Ordinal and scale covariates were included, and their bivariate significance was assessed using Spearman's rho and Kendall's Tau-b. The covariates that showed statistical significance with the weighted richness thresholds (WRT) and defined the model were the soil depth and the soil moisture regime, both of which had positive correlations.

Spatial and Temporal Dynamics of the Vegetation Cover from the Bijagual Massif, Boyacá, Colombia, during the 1986-2021 Period.

Landscape changes based on spectral responses allow showing plant cover changes through diversity, composition, and ecological connectivity. The spatial and temporal vegetation dynamics of the Bijagual Massif from 1986 to 2021 were analyzed as a measure of ecological integrity, conservation, and territory. The covers identified were high open forest (Hof), dense grassland of non-wooded mainland (Dgnm), a mosaic of pastures and crops (Mpc), lagoons (Lag), and bare and degraded lands (Bdl).

Application of Phytosociological Information in the Evaluation of the Management of Protected Areas.

The classification system of plant communities using phytosociological methods can be applied to their conservation in protected areas, as well as in establishing adequate protections and granting legal status to such areas. A new integrative index is developed to classify plant communities for the evaluation of the conservation status of protected areas, obtained from the product of three statistical indices of diversity: Syntaxonomic Distinctness, Rarefaction and Areas Prioritisation, which has been named DRA (acronym of the three indices used). The DRA is used to assess whether the status granted to Protected Areas matches the values provided by the plant communities within them and which were the basis for the identification and description of the Habitats of Community Interest (Habitats Directive-92/43/CEE).

Microbial diversity associated with the anaerobic sediments of a soda lake (Mono Lake, California, USA).

Soda lakes are inhabited by important haloalkaliphilic microbial communities that are well adapted to these extreme characteristics. The surface waters of the haloalkaline Mono Lake (California, USA) are alkaline but, in contrast to its bottom waters, do not present high salinity. We have studied the microbiota present in the shoreline sediments of Mono Lake using next-generation sequencing techniques.

Localization of nickel in tissues of Streptanthus polygaloides Gray (Cruciferae) and endemic nickel hyperaccumulators from California.

The genus Streptanthus Nutt. is one of the most important indicators of ultramafic floras in western North America. This genus contains taxa that are endemic or tolerant of ultramafic soils.

Nickel localization on tissues of hyperaccumulator species of phyllanthus L. (Euphorbiaceae) from ultramafic areas of Cuba.

Two species of perennial Phyllanthus (Euphorbiaceae) (Phyllanthus orbicularis and Phyllanthus discolor, both endemic to ultramafic areas of Cuba, and their natural hybrid, Phyllanthus xpallidus) were selected for metal localization microanalysis. Different plant tissues were analyzed by X-ray fluorescence, inductively coupled plasma-atomic emission spectroscopy, and scanning electron microscopy coupled with an energy-dispersive X-ray probe. All of the studied taxa are nickel (Ni) hyperaccumulators and significant concentrations of this element were found in different leaf and stem tissues.

Lippia: traditional uses, chemistry and pharmacology: a review.

The chemical composition, pharmacological activity and traditional uses of 52 species attributed to the genus Lippia (Verbenaceae) as used in the South and Central America, and Tropical Africa, were revised and compared. A survey of the available literature shows that these species are used mostly for the treatment of gastrointestinal and respiratory disorders and as seasoning. Additionally, some of these Lippia species showed antimalarial, spasmolitic, sedative, hypotensive and, anti-inflammatory activities.