Mexico harbors more than 10% of the planet's endemic species. However, the integrity and biodiversity of many ecosystems is experiencing rapid transformation under the influence of a wide array of human and natural disturbances. In order to disentangle the effects of human and natural disturbance regimes at different spatial and temporal scales, we selected six terrestrial (temperate montane forests, montane cloud forests, tropical rain forests, tropical semi-deciduous forests, tropical dry forests, and deserts) and four aquatic (coral reefs, mangrove forests, kelp forests and saline lakes) ecosystems. We used semiquantitative statistical methods to assess (1) the most important agents of disturbance Electronic supplementary material The online version of this article (affecting the ecosystems, (2) the vulnerability of each ecosystem to anthropogenic and natural disturbance, and (3) the differences in ecosystem disturbance regimes and their resilience. Our analysis indicates a significant variation in ecological responses, recovery capacity, and resilience among ecosystems. The constant and widespread presence of human impacts on both terrestrial and aquatic ecosystems is reflected either in reduced area coverage for most systems, or reduced productivity and biodiversity, particularly in the case of fragile ecosystems (e.g., rain forests, coral reefs). In all cases, the interaction between historical human impacts and episodic high intensity natural disturbance (e.g., hurricanes, fires) has triggered a reduction in species diversity and induced significant changes in habitat distribution or species dominance. The lack of monitoring programs assessing before/after effects of major disturbances in Mexico is one of the major limitations to quantifying the commonalities and differences of disturbance effects on ecosystem properties.

<p>Species composition, diversity, structure and microclimate were compared in two edge type of montane cloud forest (FF, edges with pine forest and FS, secondary shrubland) within a forest-edge-exterior gradient at Sierra de Manantlán Biosphere Reserve (Jalisco, Mexico). The cloud forest presented higher richness (126 species, 52 interior habitat specifi c) than pine forests (84) and shrublands (71). Richness and diversity were similar in FF, but species replacement was higher in FS. Density, diameter structure, basal area and canopy cover were major in FF than in FS. Microclimatic and soil condition, was gradual in FF edges and abrupt in FS edges. Tree species of the cloud forests (high density of seedlings and saplings &lt;5 cm diameter breast height) are colonizing the understory of adjacent pine forests, whereas in shrublands their establishment appears to be limited by competition with shrubs and herbaceous species and microclimatic conditions. Our results highlight the importance of considering edge type contrast in conservation and restoration of cloud forest in forest landscapes.</p>

El área protegida Sierra de Quila en Jalisco posee una extensa red de arroyos permanentes y temporales donde los bosques de galería mantienen importantes procesos ecológicos y de conectividad biológica. Este trabajo describe su estructura florística arbórea en siete arroyos ubicados en el intervalo altitudinal de 1 876 y 2 200 m. Se establecieron 29 sitios de muestreo de 500 m2 cada uno (1.45 ha) en los que se midieron todos los individuos leñosos >7 cm de diámetro (DN). Se registraron 881 árboles, pertenecientes a 35 especies de 17 familias, entre los taxa dominantes se registraron Alnus acuminata, Clethra hartwegii, Pinus devoniana, Prunus serotina, Styrax ramirezii y Salix bonplandiana. La riqueza específica entre localidades varió de 10 a 22 especies, mientras que el Índice de Diversidad Shannon-Wiener fue de 1.8 a 2.6 nats y el de dominancia de Simpson de 0.12 a 0.48. El análisis de agrupamiento y el análisis de escalonamiento multidimensional no métrico (NMDS) evidenciaron 40 % de similitud florística entre arroyos. Se observaron diferencias en la densidad de especies latifoliadas entre sitios (p < 0.025), esto se confirma tanto por la disimilitud en la abundancia promedio de los taxa entre los lugares con vertiente norte y sur (PERMANOVA, F = 2.45, p = 0.0001), como la registrada para la altitud de los sitios (PERMANOVA, F= 1.71, p = 0.004).

Crotalus polystictus es Una serpiente de cascabel endémica de México. Se considera bajo protección especial de acuerdo a la NOM-059-2010-SEMARNAT. Crotalus polystictus fue registrada por primera vez en el área Natural protegida Sierra de Quila, Jalisco. Este registro se encuentra a por lo mneos 31 km al noroeste del punto más cercano de su distribución conocida.

Land use in Mexico has dramatically changed in recent decades since deforested lands have been repurposed for agriculture. We evaluated the amphibian taxonomic and functional diversity of a heterogeneous landscape with ten land cover/use types in west-central Mexico. Taxonomic diversity was evaluated with q-order indices, and functional diversity was calculated with three multivariate functional diversity indices by land cover/use. The relationship between amphibian diversity, habitat structure, and environmental variables was analyzed using multidimensional distance-based analyses. Our results showed that most native land cover types exhibited a similar species richness (low values) among the studied crops, except for the riparian habitat surrounded by tropical dry forest (high richness) and secondary vegetation (intermediate richness). Regarding functional diversity, the riparian habitat surrounded by tropical dry forest, sugar cane field, and secondary vegetation had the highest values. The secondary vegetation had more functional groups than other land cover/use types. Despite the lack of a clear spatial pattern of amphibian taxonomic and functional diversity, we determined that attributes such as herbaceous cover and water availability are essential to maintain both facets with high amphibian diversity in the land cover/use types (e.g., secondary vegetation and sugar cane).