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Background and Aims: Coastal dune vegetation houses highly specialized plants that are capable of surviving adversities such as strong winds, salin-ity, high temperatures, scarcity of fresh water, burial, soil instability, and anthropogenic activities. Coastal dunes ecosystems are considered one the most dynamic systems on Earth. Their communities occur in Mexico on both the Gulf and Pacific sides. The coastal dunes vegetation of the Pacific slope are the least studied. The goals of this study were to describe, analyze and classify the coastal dune vegetation communities along the coast of the state of Jalisco, through the analysis of their composition, structure, flora, and zoning, from a geobotanical point of view with a conservation and management perspective. Methods: The phytosociological methodology of the Zürich-Montpellier sigmatist school was followed to carry out 90 inventories on 36 different beaches. The data obtained in the inventories were analyzed through partition analysis, clustering and non-metric multidimensional scaling methods.Key results: The total number of taxa recognized in the set of inventories was 83. The classification analyzes allowed us to recognize four groups linked to each of the dune fronts: 1) embryonic, 2) primary or frontal, 3) secondary and 4) tertiary or fossil dune.Conclusions: Each type of dune presents particular characteristics, both structural and floristic, that support its classification and zoning from a geo-botanical, ecological, and edaphic point of view with a conservation and planning perspective, Antecedentes y Objetivos: La vegetación de dunas costeras alberga plantas muy especializadas que son capaces de sobrevivir a adversidades como vientos fuertes, salinidad, altas temperaturas, escasez de agua dulce, enterramiento, inestabilidad del suelo y actividades antropógenas. Los eco-sistemas costeros son considerados uno de los sistemas más dinámicos de la Tierra. Sus comunidades se presentan en México tanto en la vertiente del Golfo como en la del Pacífico. Las dunas costeras de la vertiente del Pacífico son las menos estudiadas. Los objetivos del presente trabajo fueron describir, analizar y clasificar las comunidades de vegetación de dunas costeras a lo largo del litoral del estado de Jalisco, a través del análisis de su composición, estructura, flora y zonificación, desde un punto de vista geobotánico con una perspectiva de conservación y manejo. Métodos: Se siguió la metodología fitosociológica de la escuela sigmatista de Zürich-Montpellier, para realizar 90 inventarios en 36 playas diferentes. Los datos obtenidos en los inventarios se analizaron a través de los análisis de partición, métodos de agrupamiento y de escalamiento multidimen-sional no métrico. Resultados clave: El número total de taxones reconocidos en el conjunto de los inventarios fue de 83. Los análisis de clasificación permitieron reco-nocer cuatro grupos vinculados a cada uno de los frentes dunares: 1) embrionario, 2) primario o frontal, 3) secundario y 4) terciario o paleodunar. Conclusiones: Cada tipo de duna presenta características particulares, tanto estructurales como florísticas, que respaldan su clasificación y la zonifi-cación desde un punto de vista geobotánico, ecológico y edáfico con una perspectiva de conservación y planificación.

Dúas das meirandes ameazas ós montes son os incendios forestais e as especies exóticas invasoras (EEI). Neste traballo de tese trátase a relación entre ambos a través da xerminación ou os compostos alelopáticos e estudáronse tratamentos mecánicos para o control das EEI. Estudáronse 11 especies, das cales 9 son EEI presentes na Galiza e norte de Portugal, entre as que destacan diversas acacias, o eucalipto ou a albizia. As diferenzas achadas na resposta xerminativa das especies poderían mudar a composición do ecosistema tras un incendio. Tamén os aleloquímicos presentes nas follas parecen determinar a xerminación, xa que as sementes poden sentir sinais os químicos do ambiente e calibrar o mellor momento para a xerminación. Con todo isto, propuxéronse medidas de control de EEI para reducir as poboación xa establecidas.

Background and Aims: The timberline occurs as an ecosystem harboring unique forest and grassland types comprising outstanding endemic species. These vegetation types, furthermore, are the centers of capturing, recharging and transporting water so that these are regarded as provider´s nodes of environmental services. This is even more significant in intertropical mountains since these harbor large genetic reservoirs. This is the case of the Pico del Tancítaro and surrounding volcanoes, a region between 2600 and 3800 m elevation, in Michoacán, Mexico. The present study aimed to define and characterize the floristic and phytocenotic diversity, as well as recognize distribution patterns of the plant associations along the elevational gradient. Methods: Thirty five inventories were carried out following the phytosociological approach. At each inventory, a list of species, their coverage, and physical and geographical attributes of the site were compiled. Field information was later verified in the laboratory to ensure species identification; “Flora del Bajío y de regiones adyacentes” was preferably consulted. Data were further analyzed via multivariate techniques in order to define plant associations. Key results: The 35 inventories were considered as a basis to assemble the vegetation tables that support three plant associations: Gaultherio myrsinoidis-Pinetum hartwegii, Polysticho speciosissimae-Abietetum religiosae and Sibthorpio repentis-Abietetum religiosae; as well as other units of lower rank. For each one, issues, such as structure, composition, ecology, distribution and relationship with bioclimatic belts and other nearby associations were addressed. Conclusions: The floristic combinations of the associations reflect environmental variations that occur along the altitudinal gradient, including those caused by natural and/or anthropic disturbance. These associations permit a clear classification of the phytocenotic heterogeneity in the forest studied, and confirm, Antecedentes y Objetivos: El límite superior del bosque es un ecosistema que alberga comunidades herbáceas y forestales con singular presencia de endemismos y con una función relevante en la captación, recarga y transporte de agua, lo que los define como nodos de provisión de bienes y servicios ambientales. Lo anterior es de particular significado en las montañas intertropicales por ser las que resguardan un banco de germoplasma oriundo significativamente elevado. Ese es el caso del Pico del Tancítaro y volcanes circundantes, región de estudio comprendida entre 2600 y 3800 m de altitud en Michoacán, México. Este trabajo tuvo como objetivo central definir y caracterizar la diversidad florística y fitocenótica, así como las pautas de distribución de las asociaciones vegetales a lo largo del gradiente altitudinal.Métodos: Se realizaron 35 inventarios siguiendo la metodología fitosociológica; en ellos se registraron las especies, su cobertura y los atributos físico-geográficos del sitio muestreado. La información de campo fue corroborada en gabinete; para asegurar los aspectos de identificación florística se utilizó preferentemente la “Flora del Bajío y de regiones adyacentes”. Los datos fueron analizados utilizando técnicas de agrupamiento multivariadas para poder definir las asociaciones vegetales.Resultados clave: Los 35 inventarios se consideraron como base para armar las tablas de vegetación que soportan las siguientes asociaciones vegetales: Gaultherio myrsinoidis-Pinetum hartwegii, Polysticho speciosissimae-Abietetum religiosae y Sibthorpio repentis-Abietetum religiosae; así como otras de rango menor. Para cada asociación se abordaron cuestiones de estructura, composición, ecología, distribución y relación con los pisos bioclimáticos y con otras asociaciones próximas.Conclusiones: Las combinaciones florísticas propias de las asociaciones reflejan las variaciones ambientales que se suceden en el gradiente altitudinal, incluyendo las causadas por perturbación natur

Eucalyptus plantations have been established in many areas of the world due to their fast growth and profitability. In NW Spain, Eucalyptus plantations now cover a larger area than native forests. Although Eucalyptus plantations have been shown to affect biodiversity, relatively few studies have compared their effect on multiple taxonomic groups and different aspects of biodiversity. We compared herb and bird species richness and bird abundance between 14 paired patches of native deciduous forest and Eucalyptus plantations in a heterogeneous agro-forest region of NW Spain. We also investigated whether Eucalyptus plantations contribute to shifts in community composition by analysing species nestedness and turnover. We found that species richness of both herbs and birds was consistently lower in Eucalyptus plantations compared to native forests. Furthermore, the abundances of bird species characteristic of agricultural, forest, scrubland and other habitats, were all much lower in Eucalyptus plantations than in native forests. Herb and bird communities were also significantly dissimilar between the two habitats, but as a result of different ecological processes. Species turnover explained variation between habitats in herb composition, such that species present in native forests were typical for both farmland and forest habitats, whereas those present in Eucalyptus plantations were typical for scrub and farmland habitats. In contrast, bird assemblages showed a significant nested subset pattern, with fewer species in Eucalyptus plantations compared to native forests. In total, the relative abundance of cavity-nesting forest birds was at least 64% higher in native forests. Our results show that Eucalyptus plantations cannot replace native forests as they harbour different herb species and only a subset of the bird species found in native forests. Considering the current rate of increase of Eucalyptus plantations and the fragmentation of native forests in NW Spain, a lack

The agricultural and forest practices affect biodiversity. This thesis studied how different agricultural and forest management practices affect the biodiversity that depends on the agro-forestry environments of North-West Spain. All birds, butterflies and plants benefited from organic farming, with higher species richness and abundance in organic than conventional farms. In addition, organic farming resulted in a higher functional diversity of butterflies. Finally, all bird and plant species richness and diversity were higher in native forests than Eucalyptus plantations. Organic agriculture and native forests play a key role for biodiversity, and they should be prioritised in order to conserve biodiversity in North-West Spain.

Based on bioclimatic diagnosis of 377 meteorological stations throughout the physiographic province of Sierra Madre Occidental (SMO) and the floristic and vegetation information collected, have been identified bioclimatic territorial units, of which his geobotánical characterization is performed. The area is included in the Tropical Macrobioclima, where Tropical Desert, Tropical Xeric and Tropical Pluviseasonal bioclimates are presented. To each one, their bioclimatic belts have been identified (19 intotal) of which corresponding geobotánical diagnosis is made through the identification of their respective vegetation belts, emphasizing the structure of the potential natural vegetation, its main floristic markers and its catenal distribution. These results are completed with maps of bioclimates, thermotypes and ombrotypes, and three vegetation transects made at different latitudes., Con base en la diagnosis bioclimática de 377 estaciones meteorológicas repartidas por la provincia fisiográfica de la Sierra Madre Occidental (SMO) y en la información florística y de vegetación recopilada, se han identificado las unidades bioclimáticas del territorio, de las que se efectúa su caracterización geobotánica. El área se incluye en el macrobioclima tropical, estando representados los bioclimas Tropical Desértico, Tropical Xérico y Tropical Pluviestacional. Para cada uno se han identificado sus pisos bioclimáticos (19 en total) de los cuales se efectúa su diagnosis geobotánica a través de la identificación de sus respectivos pisos de vegetación, haciendo énfasis en la estructura de la vegetación natural potencial, sus principales indicadores florísticos y su distribución catenal. Estos resultados se complementan con los mapas de bioclimas, termotipos y ombrotipos y con tres catenas de vegetación realizadas a diferentes latitudes.

This doctoral investigation adress the study and geobotanical categorise of vegetation of western Michoacan applying the phytosociological methodology. To this purpose it affects the phytocenotic diversity expressed in different types of forests, their spatial distribution according to bioclimatic model and its floristic composition obtained from over 200 phytosociological field inventories. The complexity and heterogeneity of the results allowed to compare whole communities at the level of structure, floristic composition, ecological affinities, distribution and bioclimatic preferences. Thus the diagnostic species characteristic of each association, its preferred environments, their geographical jurisdiction and where are its bioclimatic distribution were selected. Broadly speaking, the differences allowed the segregation of two groups: the first integrated 12 communities what, generically, is known in the country as Temperate forest; the second brings together nine communities which are related to the concept of Tropical Forest. This discrimination highlights the importance and determination that has the index thermicityin the altitudinal limits of vegetation units. La presente memoria doctoral aborda el estudio y la tipificación geobotánica de la vegetación potencial del occidente de Michoacán mediante la aplicación de la metodología fitosociológica. Para ello se incide en la diversidad fitocenótica expresada en los diferentes tipos de bosques, en su distribución espacial de acuerdo con el modelo bioclimático y en su composición florística obtenida a partir de los más de 200 inventarios fitosociológicos de campo. . No obstante la complejidad y heterogeneidad del conjunto, los resultados permitieron comparar las comunidades a nivel de estructura, composición florística, afinidades ecológicas, distribución y preferencias bioclimáticas. De esta manera se seleccionaron las especies diagnósticas características de cada asociación, sus ambientes preferenciales, su juri

Rigorous mapping of climatic patterns outstands as one of the mayor issues concerningclimatic change. This paper investigates the extent of the bioclimatic approach to develop a rigorouscartographic methodology to express climatic diversity patterns. Michoacan, Mexico was chosen torepresent a region of complex geo-ecological layout where the Nearctic and Neotropical biogeographicalrealms converge. Bioclimatic indices were computed and their spatial expression was processed in aGeographic Information System. Ground verification was performed at 93 sites across the province. Inaddition, from 2010 until 2012, more than 2000 kilometers of roads were surveyed to gather data onisobioclimate boundaries. In total, one macrobioclimate, two bioclimate s, four thermotypes, fiveombrotypes and 14 isobioclimates were distinguished in Michoacan. The Tropical pluviseasonal bioclimatewas the predominant bioclimate, covering 56.17% of the province. The Tropical xeric covers 43.82% and theTropical pluvial is practically negligible, covering 0.01% of the entire province. The relevance of theoutcome is discussed in light of its potential use for assessing likely effects of climatic change.