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Background: Tropical montane forests are important reservoirs of carbon and biodiversity but are threatened by deforestation and climate change. It is important to understand how forest structure and aboveground biomass change along gradients of elevation and succession. Questions: What are the interactive effect of elevation and two stages of succession on forest structure parameters? Studied species: Tree communities. Study site and dates: Cofre de Perote, Veracruz, Mexico. August to December 2015. Methods: We studied four sites along an elevational gradient (500, 1,500, 2,500, and 3,500 m). At each elevation and each forest type, we established five 20 × 20 m plots (n = 40 plots). Within each plot, we measured stem density, mean diameter at breast height (dbh), and tree height and derived basal area and aboveground biomass (AGB). Results: AGB peaked at 2,500 m and was significantly related to elevation and succession, with higher values in old-growth forests than in secondary forests at higher altitudes. Lower values of mean dbh and basal area were found at higher elevations. At the lowest elevation, both successional stages had the same values of stem density and AGB. At both lower elevations, secondary forests had higher values of dbh and basal area. There were high biomass stocks in the old-growth forest at 2,500 and 3,500 m. Conclusions: Old-growth forests at higher elevations are threatened by deforestation, consequently these remaining fragments must be preserved because of their storage capacity for biomass and their ability to mitigate climate change.

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 uno. Registramos la presencia de angiospermas herbáceas terrestres dentro de 135 parcelas de 20 × 20 m, distribuidas en bosques maduros, degradados, secundarios, así como vegetación azonal. Se analizó la riqueza de especies, la composición florística y luego comparamos los datos resultantes entre los diferentes pisos altitudinales y los grados de perturbación del bosque. Resultados: Se registraron 264 especies de plantas, 31 endémicas de México y tres amenazadas. Esta riqueza representa 5.7 % de la flora de herbáceas angiospermas en Veracruz. Los pisos altitudinales con mayor riqueza de especies fueron 2,500 m (76) y 1,500 m (52). En la mayoría de los casos, los bosques secundarios tuvieron la mayor riqueza de especies en el gradiente altitudinal, mientras que los bosques maduros tuvieron menos especies. Conclusiones: La riqueza de especies observada, incluyendo elementos endémicos, resalta la importancia de esta zona para la conservación de plantas, que se encuentra amenazada por el cambio de uso del suelo. Además, sugerimos que la variación de la vegetación formada por bosques maduros, perturbados y secundarios es aceptable (e inevitable) y puede incluso incrementar la riqueza de especies.

Antecedentes y Objetivos: Los arbustos son un elemento florístico importante de los bosques tropicales; sin embargo, la investigación sobre plantas con esta forma de crecimiento aún es escasa. El objetivo principal de este estudio consistió en analizar la influencia de la elevación y la perturbación en los patrones de distribución y diversidad de los arbustos en la región central de Veracruz, México.Métodos: Se estableció un gradiente elevacional (20-3500 m s.n.m) en la ladera este del Cofre de Perote, donde se realizó un muestreo florístico en ocho pisos elevacionales separados por 500 m cada uno. Registramos la abundancia de arbustos dentro de 120 parcelas de 20 × 20 m, distribuidas en tres hábitats: bosque conservado, perturbado y secundario. Se analizó la riqueza, diversidad y composición florística; además, se compararon los datos resultantes entre los diferentes pisos elevacionales y los grados de perturbación del bosque.Resultados clave: Se registraron 118 especies y 14 morfoespecies de arbustos, lo que representa 8.6% de los reportados para Veracruz. Los fragmentos de bosque en las elevaciones de 500 y 1000 m son los más ricos en número de especies, pero también son los más susceptibles a las perturbaciones humanas. La influencia antrópica sobre estos bosques puede incrementar la diversidad de especies a nivel local, pero al mismo tiempo modifica la composición florística de un hábitat conservado a uno secundario.Conclusiones: El presente estudio es el primero en el Neotrópico en considerar y analizar los arbustos como un grupo individual a lo largo de un gradiente completo utilizando un método de muestreo uniforme y comparable. Esto permitió detectar aquellos fragmentos de bosque conservado, perturbado o secundario que son altamente diversos y susceptibles a los distrubios antrópicos. Estos sitios sirven como zonas estratégicas de amortiguación y refugio de este grupo de plantas, ya que independientemente de la intensidad de su uso, estos podrían y deberían considerarse en futuros planes de conservación en esta región amenazada por la degradación ambiental.

The use of non-timber forest products forms part of the strategy contributing to the well-being of populations near forest areas. Chamaedorea is one of the most important palm genera that is globally commercialized profitably for its attractive foliage used in floral decorations. In our study area located in the central region of Veracruz, Mexico we identified changes in tree cover between 1973 and 2017 using the normalized difference vegetation index (NDVI). We conducted plant surveys to identify tree species richness associated with the cultivation of C. elegans. We conducted semi-structured interviews with local palm producers to understand their perceptions regarding changes in tree cover in the study area and its association with the presence of the camedor palm. Soil cover patterns and vegetation index signatures indicated an increase in the forested area from 1973 to 2017 (after more than 43 years), with a 69% gain in secondary vegetation coverage with low NDVI values. This increase is associated with the cultivation of palm, since arboreal cover had previously been dominated by species traditionally used as shade for camedor cultivation. Tree diameters at breast height (DBH) were low, indicating young secondary forests with low recruitment and diversity in the understory suggestive of simplified species assemblages; most of the associated species were long-living pioneers and typical of the secondary forest favored by the palm producers. Producers mentioned they did not remove coffee because it is their main means of subsistence, and in combination with the palm, there is greater economic benefit. They also confirmed an increase in forest cover owing to the introduction of palm cultivars in the areas north and south of the study area. This was confirmed with the NDVI results, which detected the same spatial pattern. These changes resulted in the interruption of the processes of succession without the transition of secondary to old-growth forests. However, the canopy of the study area provides better environmental services than did the previously existing vegetation cover. This study showed the need for the assessment of non-timber forest products as key indicators of land use change and alterations in associated plant cover.

México is a cultural and biological megadiverse country with an increased anthropogenic pressure on its tropical landscapes. The study area was the ejido “Los Ídolos”, Misantla, Central Veracruz, Mexico. The main objective of this research was to identify how the woody plant diversity of agroforestry systems contributed to the cultural, economic, and subsistence security of local farmers. Five different agroforestry systems were identified: forest gardens (FG), home gardens (HG), plantation crop combination with perennial cultivates (PC), plantation crop combinations with annual cultivates (AC), and trees on pastures (TP). FG systems had the highest floristic diversity, followed by HG and TP. Interviews with farmers showed that FG, HG, and PC systems were important for maintaining cultural identity and secure subsistence needs, while PC and TP systems were important for improving the economic situation of farmers. The FG systems contained only native species, while the proportion of exotic plants differed among the other systems. Useful exotic plants were found in the HG system. This study demonstrated that agroforestry systems such as FG were not used to their full potential, despite their high diversity of useful plants. It is recommended that farmers—assisted by institutions and representatives of local product chains—conduct feasibility studies on the marketing and promotion of products derived from specific agroforestry systems.

Wild edible fruits are a complement to the diet, generate income, and contain cultural values for local populations. In Mexico, their presence is threatened mainly by deforestation. The purpose of ...

Deforestation and fragmentation are threats to the conservation of species and have consequences for ecosystem functions. The focus of this study was to elucidate forest cover change in the period of 1993 to 2014. Our study area is in the central region of Veracruz, Mexico. Land cover and land use classes for the Years 1993, 2000, and 2014 were derived from Landsat images applying supervised classification. Then, we quantified the net change in forest area, the loss of original forest area, and evaluated forest fragmentation using landscape metrics. Our results showed that the area covered by remnant forests decreased 57%. The annual net forest cover change rate for 1993 to 2000 was −0.44%; since then forest cover increased at a rate of 0.11% from 2000 to 2014. The decreasing total edge density and the mean proximity index during the entire period of the study indicate decreasing irregularity in the shape of remnant forest patches and a slight decrease of vulnerability to edge effects. Forest patches augm...