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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 From sea level close to the Gulf of Mexico 81 km away in a direct line on the eastern slopes of the Cofre de Perote at 3500 m, central Veracruz, Mexico. Methods We studied the richness and composition of fern assemblages in 120 study plots at eight elevations from 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 yr 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 drier 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 was together with a reduction in fern species richness of 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.

The abundance, species richness, similarity and dominance of braconid parasitoid wasps were estimated for 4 types of land use (secondary forest, rubber plantations, living fences and pastures), and remnants of preserved tropical rain forest in southern Mexico. We also analyzed whether specialist (koinobionts) taxa are more negatively affected by forest disturbance than generalists (idiobionts), and whether braconid abundance is correlated with adult host abundance. Braconids were sampled using 3 Malaise traps for each type of land use during March 2010 and May 2011. We collected 143 individuals belonging to 65 species and 15 subfamilies. Species richness and abundance were higher in preserved and secondary forests, than in other types of land use. Although abundance and richness were low in pastures, these sites potentially contain hosts for braconids. We detected no variation in abundance or species richness by land use, even when comparing idio-and koinobionts. The most dominant species belonged to the genera Apanteles (Microgastrinae) and Hetersopilus (Doryctinae) in all land use types, except pasture, where Bracon (Braconinae) dominated. We detected a positive relationship between braconids and adult host abundance. Altogether, the 4 types of land use and the preserved forest are able to host a diverse braconid community.

This study analyzes the potential uses of live fences and pastures as reservoirs of plant diversity for two regions with different management histories, Los Tuxtlas (LT) and Uxpanapa (UX), Veracruz, México. We studied two habitats, live fences and pastures, analyzed their species richness, diversity, structure and plant composition and classified species according to plant regeneration modes (light-demanding and shade tolerant), seed dispersal syndrome and their local uses. We recorded 62 species of trees at LT and 48 at UX. Live fences were more diverse than pastures in both regions. The LT site showed to analyze the relationship a higher diversity of plants in regeneration stages than the one at UX. However, UX had higher diversity of adult plants in the pastures than LT. Composition and structure of live fences were different between regions, as well as within live fences and pastures, 53 % of species were light-demanding and 40 % were shade tolerant; 70 % of the species were dispersed by birds. Differences between sites are associated with the modifications in live fences structure, which changed according to managerial practices and the use of local species; this may influence plant regeneration modes as well as the visits of avian dispersal agents. In LT, all species found in live fences were useful to humans, whereas in UX, less than half were used by the local population. Our results underline the importance of live fences and isolated trees in pasture habitats as potential sites to host native and useful species from tropical rain forests in livestock landscapes.