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Blanca aida vargas higinio
Blanca aida vargas higinio













blanca aida vargas higinio

This study indicated the importance of elevation at both local and regional spatial scales as an important driver in Quercus‐dominated forests distribution, probably related to Quercus species adaptation to temperature and precipitation. The analysis also tested the variation of species community composition over environmental gradients mainly determined by elevation. At the local scale, elevation accounted for the highest variation followed by maturity, P, N, and Mg. At the regional scale, elevation, aspect, litter, maturity, and Mg were significant in explaining species community composition elevation variance was twofold higher than variance for aspect and litter. Results showed that both local and regional spatial variables significantly control species composition in Quercus‐dominated forests, with the regional scale accounting for a higher explained variance than the local scale. Redundancy analysis and variance partitioning were run to reveal the relative importance of environmental and spatial processes explaining plant species composition of Quercus‐dominated forests and ascertain the environmental variables controlling the species composition at the different spatial scales (local and regional). Local spatial variables were derived from distance‐based Moran's eigenvector maps, while regional spatial variables were obtained from geographical coordinates (latitude/longitude). A database of 86 plots, randomly located in a highly diverse spot of the Mexican Neotropics, was examined it involved vegetation, environment, and spatial data. This study aims to comprehend the contribution of environmental and spatial processes influential in species composition of Quercus‐dominated forests. Quercus‐dominated forests in the Neotropics compose one of the broadest distributed ecosystems of mountainous zones whose species distribution has been explained by climate change adaptation over an abrupt physiography. Nonetheless, it was not clear if local signals were more diverse than regional signals or that lowland signals were more diverse than highland signals. Our results indicated that forests with a tropical component were more diverse than forests with Holarctic affinities. We used seven diversity metrics along with abundance estimation (Rarefaction, Pielou evenness, Shannon diversity, Hill numbers: N0, N1 and N2 and Rate of Change). They comprised highland and lowland vegetation from 0 to 3860 m asl representing local and regional signals in mangrove forest, tropical evergreen forest, tropical subdeciduous forest, pine forest, pine-oak forest and cloud forests in different regions of Mexico. Therefore, in order to discern differences in taxon diversity in tropical and temperate ecosystems during the Holocene, 15 sites with palaeoecological data retrieved from several sources (lakes, lagoons, ponds, a moraine depression and forest hollows) were studied. For the Holocene, palaeoclimatic and palaeoecological records have revealed that climate change is an essential factor involved in this diversification. These natural processes have produced dissimilarities in forest composition along the different regions of the Mexican territory. The western region is geologically linked to volcanic forcing, which in turn was responsible for mountain uplift while the east was formed by tectonic movement in a steady and gradual process allowing the development of rare taxa. The forests of Mexico have conclusive environmental characteristics mainly shaped by geology and climate change.















Blanca aida vargas higinio