In the Neotropical area of the Río Apatlaco sub-basin (central Mexico), high deforestation can be attributed to urban development, as this area concentrates the highest human population density in Morelos state. The objective of this study was to analyze changes in land use and vegetation in this sub-basin from 2002 to 2012 using geographic information systems. The results show that, over the period of analysis, the main changes occurred in the grassland and coniferous forest. However, in the tropical dry forest (TDF) the annual rate of deforestation (0.13%) was much lower than previously estimated (1.4%), but no recovery took place. It is possible that deforestation of the TDF was halted because the remaining areas with forest remnants were unsuitable for agricultural activities and/or abandonment of such activities has taken place. It is therefore a priority to protect these areas of secondary vegetation that serve as a buffer for conserved areas, allowing their recovery and contributing to their interconnectivity. Key words:Land cover change, Rio Apatlaco, Geographic Information Systems. RESUMENEn la zona Neotropical de la sub-cuenca del río Apatlaco (centro de México), la alta deforestación puede ser atribuida al desarrollo urbano, ya que esta zona concentra la mayor densidad de población del Estado de Morelos. El objetivo de este estudio es analizar los cambios en el uso del suelo y de la vegetación en esta subcuenca entre 2002 y 2012, utilizando Sistemas de Información Geográfi ca. Los resultados muestran que, durante el período de análisis, los principales cambios ocurrieron en los pastizales y bosques de coníferas. Sin embargo, el bosque tropical caducifolio (BTC) sufrió una tasa anual de deforestación (0,13%) mucho más baja que la estimada previamente (1,4%), pero no ocurrió una recuperación. Es posible que la deforestación del BTC se haya detenido, debido a que las áreas con remanentes de bosque, son inadecuados para la agricultura u otras actividades. Es una prioridad proteger las áreas de vegetación secundaria, pues sirven como un amortiguador para las áreas fragmentadas, lo que permitiría su recuperación y contribuir a su interconectividad.Palabras clave: Cambio de cobertura del suelo, río Apatlaco, Sistemas de Información Geográfi ca.

RESUMENEn la zona Neotropical de la sub-cuenca del río Apatlaco (centro de México), la alta deforestación puede ser atribuida al desarrollo urbano, ya que esta zona concentra la mayor densidad de población del Estado de Morelos. El objetivo de este estudio es analizar los cambios en el uso del suelo y de la vegetación en esta subcuenca entre 2002 y 2012, utilizando Sistemas de Información Geográfi ca. Los resultados muestran que, durante el período de análisis, los principales cambios ocurrieron en los pastizales y bosques de coníferas. Sin embargo, el bosque tropical caducifolio (BTC) sufrió una tasa anual de deforestación (0,13%) mucho más baja que la estimada previamente (1,4%), pero no ocurrió una recuperación. Es posible que la deforestación del BTC se haya detenido, debido a que las áreas con remanentes de bosque, son inadecuados para la agricultura u otras actividades. Es una prioridad proteger las áreas de vegetación secundaria, pues sirven como un amortiguador para las áreas fragmentadas, lo que permitiría su recuperación y contribuir a su interconectividad.Palabras clave: Cambio de cobertura del suelo, río Apatlaco, Sistemas de Información Geográfi ca. ABSTRACTIn the Neotropical area of the Río Apatlaco sub-basin (central Mexico), high deforestation can be attributed to urban development, as this area concentrates the highest human population density in Morelos state. The objective of this study was to analyze changes in land use and vegetation in this sub-basin from 2002 to 2012 using geographic information systems. The results show that, over the period of analysis, the main changes occurred in the grassland and coniferous forest. However, in the tropical dry forest (TDF) the annual rate of deforestation (0.13%) was much lower than previously estimated (1.4%), but no recovery took place. It is possible that deforestation of the TDF was halted because the remaining areas with forest remnants were unsuitable for agricultural activities and/or abandonment of such activities has taken place. It is therefore a priority to protect these areas of secondary vegetation that serve as a buffer for conserved areas, allowing their recovery and contributing to their interconnectivity.

1. Ants are the dominant insects in tropical forest canopies. The α and β diversities of ants change in response to forest disturbance. Understanding the response of ants to forest disturbance will help to guide ant conservation and forest management plans, especially in endangered ecosystems such as the tropical dry forest. 2. We analysed ant α and β diversities in 15 fragments (5 mature, 5 disturbed, and 5 secondary) of a tropical dry forest in central Mexico. We identified and measured all of the trees in two transects (10 × 50 m) established within each fragment. Pit‐fall traps were used to sample ants in all of the trees. 3. We identified 52 ant species (from a total of 11,524 individuals). The mature forest presented the greatest quantity of exclusive species and the highest α diversity. Ant composition differed among the mature forest but not between disturbed and secondary forest, and was related to tree size and richness. The β diversity was lower in the disturbed forest, reflecting the cost of biotic homogenization (15%). Among the β diversity components in all three forest types, this diversity was mainly influenced by turnover, while nestedness diminished in the disturbed forest. 4. In the tropical dry forest studied, anthropogenic disturbance homogenises the ant community, probably because the availability of resources is also homogenised, decreasing the α diversities of the canopy ants. Our results show the importance of the conservation of mature forests in terms of maintaining the diversity of canopy ants.

No abstract