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In the Yucatan Peninsula, two species of the genus Haematoxylum grow: Haematoxylum campechianum and Haematoxylum calakmulense. The objective of this study was to evaluate the current status of the populations of both species at different sites in Campeche, Mexico. In order to know the historical and current distribution, published herbarium records, project information, and field expeditions were used. Eight sites with concentrations of individuals of one of the species or the other were selected to measure population density and structure, and 20 plots of 10 x 10 m were established at each site. In the plots, individuals of both species were counted and measured with trunk diameter at chest height (DBH) greater than 1 cm. For each individual the height, DBH and number of branches were recorded. We compared the variables density, height, DBH, number of branches between sites and the absolute frequencies of the size intervals and DBH within each site. Haematoxylum campechianum is widely distributed in the state of Campeche and was located forming seasonally inundated forests and as isolated trees, while H. calakmulense was recorded in interior areas of the state with lower density values than H. campechianum; none of the sites were found forming seasonally inundated forests. For H. calakmulense the highest individuals reached 12 m and for H. campechianum 15 m. Considering the economic potential, each species may be affected by anthropogenic activities that cause their populations to decline in the medium and long term., En la Península de Yucatán se desarrollan dos especies del género Haematoxylum: Haematoxylum campechianum y H. calakmulense. El objetivo del presente trabajo fue evaluar el estado actual de las poblaciones de ambas especies en diferentes sitios en Campeche, México. Para conocer la distribución histórica y actual se utilizaron registros de herbarios publicados, información de proyectos y expediciones de campo. Para medir la densidad y la estructura dasométrica se seleccionaron ocho sitios con concentraciones de individuos de una u otra especie, y se establecieron 20 parcelas de 10 x10 m en cada sitio. En las parcelas se contabilizaron y midieron los individuos de ambas especies con diámetro del tronco a la altura del pecho (DAP) mayor de 1 cm. Para cada individuo se tomó la altura, DAP y número de ramas. Se compararon las variables densidad, altura, DAP, número de ramas entre sitios y las frecuencias absolutas de los intervalos de tamaño y DAP dentro de cada sitio. Haematoxylum campechianum se encuentra ampliamente distribuido en el estado de Campeche y se localizó formando tintales y como árboles aislados. Mientras que H. calakmulense se encuentra en zonas interiores del estado con valores de densidad menores que H. campechianum, en ninguno de los sitios se encontró formando tintales. Para H. calakmulense los individuos más altos alcanzaron 12 m y para H. campechianum 15 m. Considerando el potencial económico, cada especie puede verse afectada por actividades antropogénicas que provoquen la disminución de sus poblaciones a mediano y largo plazo.

Background and Aims: Biological invasions are considered as second to habitat loss as a cause of the extinction of species. The study of population dynamics is particularly relevant for species with expansive behavior. The aims of this study were to: (1) evaluate the population ecology of Oncidium poikilostalix in shaded coffee plantations in Mexico, (2) evaluate the reproductive behavior of O. poikilostalix in this habitat, and (3) determine whether this orchid should be considered as an invasive species. Methods: During 2013-2015, most of the individuals of the Mexican population of O. poikilostalix (located south of the state Chiapas) were marked and measured. Additionally, the flower and fruit production (first flowering and repeated flowering), mortality and recruitment of new individuals were registered annually, and its potential distribution was modeled. Key results: Within this period a population increase of 1.11% was observed, with a proportional increase in the number of flowers and fruits. There was a strong correlation between the leaf area of individuals and the production of flower spikes (R=0.690, p<0.001) and flowers (R=0.775, p<0.001). The number of mature individuals that had repeated flowering varied from 47.1% in 2013 to 22.5% in 2015. There was also correlation between the leaf area of individuals with the fact that they do not flower, flower once and repeated flowering (X2=277.65, p<0.001). The Mexican population of O. poikilostalix is located on the northern limit of the potential distribution of this species. Conclusions: It is unlikely that O. poikilostalix behaves as an invasive species. Despite being a locally abundant taxon, with an apparently healthy population established in traditional shaded coffee plantations, its distribution in Mexico is limited, which may represent a serious risk to its survival in the country., Antecedentes y Objetivos: Las invasiones biológicas se consideran la segunda causa de extinción de especies después de la destrucción del hábitat. Cuando se trabaja con especies con una tendencia expansiva, los estudios de dinámica poblacional son particularmente relevantes. Los objetivos de este estudio fueron: (1) evaluar la ecología poblacional de Oncidium poikilostalix en cafetales de sombra en México, (2) evaluar el comportamiento reproductivo de O. poikilostalix en este hábitat, y (3) determinar si esta orquídea se debe considerar como una especie invasora. Métodos: Durante 2013-2015 se marcaron y midieron la mayoría de los individuos de la población mexicana de O. poikilostalix (localizada al sur del estado de Chiapas). Además, se registraron anualmente la producción de flores y frutos (primera floración y floración repetida), la mortalidad y el reclutamiento de nuevos individuos, y se modeló su distribución potencial. Resultados clave: Dentro de este periodo se observó un incremento poblacional de 1.11%, con un aumento proporcional en el número de flores y frutos. Existe una fuerte correlación entre el área foliar de los individuos, y la producción de espigas (R=0.690, p<0.001) y flores (R=0.775, p<0.001). El número de individuos adultos que tuvieron floración repetida varió de 47.1% en 2013 a 22.5% en 2015. También se encontró correlación entre el área foliar de los individuos y el hecho de que no florezcan, florezcan una vez, o presenten floración repetida (X2=277.65, p<0.001). La población mexicana de O. poikilostalix se localiza en el límite norte de la distribución potencial de esta especie. Conclusiones: Es poco probable que O. poikilostalix sea una especie invasora. A pesar de ser un taxon localmente abundante, con una población aparentemente sana establecida en cafetales tradicionales de sombra, su área de distribución en México aún es restringida, lo que puede representar un grave riesgo para su supervivencia en el país.

Background and Aims: Biological invasions are considered as second to habitat loss as a cause of the extinction of species. The study of population dynamics is particularly relevant for species with expansive behavior. The aims of this study were to: (1) evaluate the population ecology of Oncidium poikilostalix in shaded coffee plantations in Mexico, (2) evaluate the reproductive behavior of O. poikilostalix in this habitat, and (3) determine whether this orchid should be considered as an invasive species. Methods: During 2013-2015, most of the individuals of the Mexican population of O. poikilostalix (located south of the state Chiapas) were marked and measured. Additionally, the flower and fruit production (first flowering and repeated flowering), mortality and recruitment of new individuals were registered annually, and its potential distribution was modeled. Key results: Within this period a population increase of 1.11% was observed, with a proportional increase in the number of flowers and fruits. There was a strong correlation between the leaf area of individuals and the production of flower spikes (R=0.690, p<0.001) and flowers (R=0.775, p<0.001). The number of mature individuals that had repeated flowering varied from 47.1% in 2013 to 22.5% in 2015. There was also correlation between the leaf area of individuals with the fact that they do not flower, flower once and repeated flowering (X2=277.65, p<0.001). The Mexican population of O. poikilostalix is located on the northern limit of the potential distribution of this species. Conclusions: It is unlikely that O. poikilostalix behaves as an invasive species. Despite being a locally abundant taxon, with an apparently healthy population established in traditional shaded coffee plantations, its distribution in Mexico is limited, which may represent a serious risk to its survival in the country., Antecedentes y Objetivos: Las invasiones biológicas se consideran la segunda causa de extinción de especies después de la destrucción del hábitat. Cuando se trabaja con especies con una tendencia expansiva, los estudios de dinámica poblacional son particularmente relevantes. Los objetivos de este estudio fueron: (1) evaluar la ecología poblacional de Oncidium poikilostalix en cafetales de sombra en México, (2) evaluar el comportamiento reproductivo de O. poikilostalix en este hábitat, y (3) determinar si esta orquídea se debe considerar como una especie invasora. Métodos: Durante 2013-2015 se marcaron y midieron la mayoría de los individuos de la población mexicana de O. poikilostalix (localizada al sur del estado de Chiapas). Además, se registraron anualmente la producción de flores y frutos (primera floración y floración repetida), la mortalidad y el reclutamiento de nuevos individuos, y se modeló su distribución potencial. Resultados clave: Dentro de este periodo se observó un incremento poblacional de 1.11%, con un aumento proporcional en el número de flores y frutos. Existe una fuerte correlación entre el área foliar de los individuos, y la producción de espigas (R=0.690, p<0.001) y flores (R=0.775, p<0.001). El número de individuos adultos que tuvieron floración repetida varió de 47.1% en 2013 a 22.5% en 2015. También se encontró correlación entre el área foliar de los individuos y el hecho de que no florezcan, florezcan una vez, o presenten floración repetida (X2=277.65, p<0.001). La población mexicana de O. poikilostalix se localiza en el límite norte de la distribución potencial de esta especie. Conclusiones: Es poco probable que O. poikilostalix sea una especie invasora. A pesar de ser un taxon localmente abundante, con una población aparentemente sana establecida en cafetales tradicionales de sombra, su área de distribución en México aún es restringida, lo que puede representar un grave riesgo para su supervivencia en el país.

Augmented reality mixes computer generated graphics with real imaging using computer vision techniques. However, nowadays, augmented reality is still a very young field of research, and its applications usually involve predefi ned tags. This thesis has been directed to use computer vision and arti cial intelligence techniques to explore the viability of using natural landmarks as key points for computer graphics reference. Moreover, there are many techniques that infer 3D scenes from images like stereo-vision, structures from motion, depth images, shape from shading, etc. The aim of this work is to find a way of doing this from one single shot image. Finally, new virtual elements will be integrated on the final scene using contextual colors. The followed methodology has been to automatically segment an image in small planar surfaces using di fferent granularities of small regions. Each region is assumed to likely lie on only one planar surface, and thus it the 3D face that it came from can be inferred. The normal vector of the planes corresponding to the 3D faces are approximated along a discrete set of orientations. In addition, some regions do not have a regular orientation and thus, they are assumed as a texturized or porous region. Inferring the fi nal 3D orientation and location from the set of labelled regions is a non-trivial task. This work proposes a method based on the coherent topology of the neighborhood. The 3D position of each point of a region is found and a 3D scenario can be obtained. After that, the regions of the original images are textured in the 3D reconstructed faces. Finally, a color transfer approach is used to integrate new 3D objects inside the final scene.