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Las montañas cubren un 12% de la superficie terrestre y un 23% del territorio de México. Tomando como base lo anterior, el objetivo es poner al alcance de los lectores una definición actual y objetiva de lo que es una montaña, así como informarles de manera simple acerca de su importancia biológica como guardianas de la biodiversidad y proveedoras de servicios ecosistémicos. Para esto, realizamos una búsqueda documental sobre el tema ecología de montaña. Nuestro principal interés es que se reconozcan a las montañas como sitios prioritarios para la conservación debido a los múltiples beneficios que suministran a la humanidad. Desafortunadamente, muchas de las montañas en el mundo y en México se encuentran bajo diferentes amenazas.

Background: The loss of functional keystone species may lead to the loss of key functions in the ecosystem. Few studies so far have addressed the functionality of specific morphological traits of f...

Questions How do species richness and composition of fern assemblages change with elevation and, within elevational belts, in differently impacted forest habitats? Is there a relationship between fern assemblages and microclimate, both along gradients of elevation and disturbance? Which species are most sensitive to habitat disturbance and microclimatic changes? Location The transect starts at sea level close to the Gulf of Mexico and ends 81 km away in a direct line on the eastern slopes of the Cofre de Perote at 3500 m, in central Veracruz, Mexico. Methods We studied the richness and composition of fern assemblages in 120 study plots at eight elevations at 20-3500 m in three forest types: natural forest (NF), disturbed forest (DF) subjected to timber extraction and grazing, and secondary forest (SF) regrown after total clearance 15-20 years ago. In addition, we measured microclimatic conditions in the three forest types at five elevations over a year. Results Fern richness peaked in humid montane forests at mid-elevations and was low in the dryer habitats at the ends of the gradient. Humid montane forests were most sensitive to disturbance, showing increases in mean annual temperatures by about 1°C and reduction in relative air humidity by about 20% in DF and SF compared to NF. This went along with a reduction of fern species richness by 5-60% and marked changes in species composition. In contrast, drought-deciduous forests at low elevations and coniferous forests at high elevations already had low humidity and high light intensity in NF and were less affected by human impact: Their microclimatic conditions and fern assemblages did not change markedly in DF and SF. Conclusions The conservation of much of the humidity-dependent biota (ferns and presumably also groups such as bryophytes and amphibians) in humid montane forests depends on the protection of natural fragments without human disturbance. In contrast, the naturally open forests at the ends of the gradient can be subjected to some exploitation while conserving much of their fern flora as long as a general forest structure is maintained. This article is protected by copyright. All rights reserved.

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.