Las aves son uno de los grupos de vertebrados más importantes en el funcionamiento de los ecosistemas al cumplir con importantes funciones como la polinización o dispersión de semillas. Sin embargo, ...las comunidades y sus poblaciones se pueden ver afectadas por cambios en los ecosistemas. Estas modificaciones pueden ser reflejo de los diferentes usos de la tierra, por lo que es importante analizar cómo las áreas con diferentes usos de suelo y coberturas influyen en las comunidades de aves. Para este estudio, realizamos muestreos de aves de febrero a junio de 2017 utilizando redes de niebla en cuatro sitios con distintas condiciones de uso: un sitio con vegetación conservada (Reserva de la Biósfera de Calakmul), dos acahuales, uno agrícola, otro forestal y un sitio ganadero. La diversidad de las comunidades fue diferente en cada uno de los sitios muestreados, se identificó que las comunidades de aves en los acahuales y la Reserva de la Biósfera de Calakmul son más similares a las del sitio ganadero. El gremio de los semilleros y las aves generalistas fueron más abundantes en el sitio ganadero. El 39% de las especies estuvo presente en la reserva de Calakmul, que fue el sitio con la comunidad más diversa (D1= 36.38); el sitio ganadero estuvo dominado por un menor número de especies (D2= 3.88). Los análisis multivariados mostraron que el tipo de vegetación presente en los sitios influye en la abundancia de familias y especies de aves (Dev= 373.1, p= 0.001). La presencia de especies compartidas entre los acahuales y la Reserva de la Biósfera de Calakmul demuestra la importancia en la conservación y regeneración de acahuales ya que son estados de transición que ayudan a recuperar especies presentes en las selvas maduras y que se encuentren bajo alguna categoría de riesgo.
The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database ...of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
The collation of biodiversity datasets with broad taxonomic, biogeographic, and spatial extents is necessary to understand historical declines and to project—and hopefully avert—future declines. We describe and make freely available a database of more than 3.2 million biodiversity measurements from 94 countries representing over 47,000 species, collated from 480 existing spatial comparisons of local‐scale biodiversity exposed to different intensities and pressures relating to land use, from terrestrial sites around the world.
Patterns of diversity of bats in the Biosphere Reserve Selva El Ocote, Chiapas, Mexico. Bats have been considered as a model group for studies on biodiversity in the Neotropics. Taxonomic diversity ...and functional categories of bats were analyzed in the Selva El Ocote Reserve. Bats were captured using mist-nets, and environmental and vegetation data were collected in four localities between January and September, 2015. Alfa diversity was estimated using Hill's numbers and rarefaction-extrapolation and abundance-rank curves. Beta diversity was evaluated by similarity indexes and Wilson-Schmida's species- turnover index. Canonical Correspondence Analysis was performed to explore associations between bat species and functional categories and environmental and vegetation variables. We recorded 37 bat species, 17 to 27 species in the sampled localities; moreover, 14 restricted species among three localities. Phyllostomidae family and the frugivorous guild were the richest and most abundant groups, Artibeus jamaicensis was the most frequent species. We found association between bat diversity and the vegetation variables group (F= 1.6588, P= 0.005), however there were no associations with environmental variables. Positive relationship was found between floristic diversity and bat diversity (r = 0.94, P=0.001). The species Trachops cirrhosus and Dermanura tolteca were related positively with tree density and Artibeus lituratus, Dermanura phaeotis and Platyrrhinus helleri were associated with tree diversity. The bat assemblages presented high similarity, forming nested subsets. Forests fragments with less human intervention harbored mores species richness and habitat specialist bats, whose permanence will depend directly of the degree of forest conservation.
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