Riqueza y distribución de angiospermas herbáceas a lo largo de gradientes de elevación y perturbación del bosque en el centro de Veracruz, Méxic

Background: Terrestrial herbs are a significant floristic element of tropical forests; however, there is a lack of research focused on this plant group. Question: Which are the patterns of species distribution of herbaceous angiosperms along gradients of elevation and forest disturbance at Cofre de Perote, central Veracruz, Mexico? Studied species: Terrestrial herbaceous angiosperms. Study site and years of study: Eastern slopes of Cofre de Perote, central Veracruz, Mexico; from 2012 until 2014. Methods: We established an elevational transect (40 to 3,520 m), where floristic sampling in eight study sites within elevational belts of about 500 m each were realized. We recorded the occurrence of terrestrial angiosperm herbs within 135 20 × 20 m plots, distributed in old-growth, degraded forest, secondary vegetation, as well as azonal vegetation. Species richness and floristic composition were compared between the different elevational belts and forest disturbance. Results: We recorded a total of 264 herb species, 31 endemic to Mexico and three classified as threatened. This number of species represents 5.7 % of Veracruz’s herbaceous angiosperm flora. The highest species richness was recorded at 2,500 m (76) and 1,500 m (52). In most of the cases, secondary forests showed the highest species richness independently of the elevational gradient, whereas old-growth forests had fewer species. Conclusions: The observed species richness, including endemic elements, highlights the importance for plant conservation of the area which is threatened by land use changes. Additionally, we suggest that vegetation variations formed by mature, disturbed and secondary forests is acceptable (and unavoidable) and can even increase species richness. Antecedentes: Las hierbas terrestres son un elemento florístico importante de los bosques tropicales; sin embargo, aún es escasa la investigación centrada en este grupo de plantas. Pregunta: ¿Cuáles son los patrones de distribución de especies de angiospermas herbáceas a lo largo de gradientes de altitud y de perturbación en el Cofre de Perote, centro de Veracruz, México? Especies de estudio: Angiospermas herbáceas terrestres. Sitio de estudio y años de estudio: Vertiente este del Cofre de Perote, centro de Veracruz, México; desde 2012 hasta 2014. Métodos: Establecimos un gradiente altitudinal (40 a 3,520 m), donde realizamos un muestreo florístico en ocho sitios de estudio dentro de pisos altitudinales de aproximadamente 500 m cada un