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Protected Areas (PAs) play a crucial role in the conservation and appreciation of the biological, ecological and socio-cultural elements of the landscape. These areas, in line with their creation objectives, provide various environmental services such as watershed protection, landscape and biodiversity preservation, and regulation of ecosystem processes. Additionally, they offer opportunities for research, education, and environmental training. Researchers from the Facultad de Agronomía, UNLPam are currently conducting two projects related to the theme of fire in Parque Nacional Lihué Calel, focusing on the impact of recurrent wildfires and the assessment of prescribed burns. Undertaking such investigations within a national park creates an interdisciplinary and interinstitutional working space, addressing various topics with the aim of transforming gathered information into practical management tools. Collaboration with PA technicians is essential to achieve the proposed objectives and serves as the link between information generation and effective implementation. [ABSTRACT FROM AUTHOR]

Alternative Biome States theory (ABS) helps to explain the presence of open biomes (grasslands, shrublands) in environments sufficiently warm and humid for the development of forest biomes. In these environments it is possible to find areas dominated by open biomes that, according to this theory, respond mainly to fire and herbivory. The aims of this work are to identify whether there are different types of forest biome-open biome ecotones based on woody composition, describe them and explore their relationship with livestock management and environmental variables, using a protected area in Uruguay as a case study. We sampled woody vegetation and other environmental variables in transects (delimited in 200m) in 10 sites across four livestock management systems. We identified two types of forest biome-open biome ecotones, one dominated by shrubland and the other dominated by grassland. Our results agree with the ABS theory and suggest the mechanisms determining the woody composition and the structure of the ecotone vegetation are cattle and use of fire and/or rotary cutter. The changes in vegetation structure and woody richness were partly abrupt, which is consistent with what is proposed by the ABS theory. However, the composition also interacted with site factors such as rockiness and distance to the watercourse, suggesting that site-level environmental variables are acting synergistically with vegetation removal to determine vegetation composition. We found that these ecotones are sensitive to management and environmental variables; so, it is necessary to incorporate this landscape and site heterogeneity to articulate productive activity with nature conservation. [ABSTRACT FROM AUTHOR]

Leaf functional traits in a plant community are the result of the effect of environmental conditions and have a direct impact on ecosystem properties and functioning. We analyzed the variations of five leaf functional traits in plant communities from central Argentina under different climatic conditions and anthropogenic use determining changes in physiognomy. Study sites were located in Córdoba province (Argentina) within four phytogeographic units categorized according to their climatic condition based on an aridity index; they were named as 'climatic units' 1, 2, 3 and 4, following a gradient from lower to higher temperature and aridity. In each climatic unit we selected six sites located in two physiognomies corresponding to different degrees of anthropogenic use: 3 sites in woodlands (less use), and 3 sites in grasslands/shrublands (more intense use). We measured five leaf traits (specific leaf area [SLA], leaf dry matter content [LDMC], leaf toughness, leaf thickness and decomposability), and we calculated the community weighted mean for each trait for each site. The variations in functional leaf traits were mainly determine by climatic conditions. The physiognomic change, because of anthropogenic use, also affected these variations, but this effect was conditioned by climate. Under colder and wetter climatic conditions, the removal of tree species result in communities dominate mainly by grasses with conservative foliar trait values (e.g., lower SLA, higher leaf toughness and lower decomposability). However, in warmer and drier climatic conditions, the removal of tree species did not imply a change in the functional strategy of the community as it resulted in an increase dominance of grasses and dicotyledonous shrub species with relatively lower foliar toughness and high decomposability. Our results show the interactive effect of climate and anthropogenic use on the variations in leaf functional traits and the complexity to predict the effects of such variations on ecosystem processes. [ABSTRACT FROM AUTHOR]

Sesleria argentea inhabits in biotopes with glacial/periglacial morphology in South Iberian high mountains. Carici flaccae-Seslerietum argenteae ass. nova is a meadow in oozing soils. A micro-"borreguil" in peaty substrates with Carex lepidocarpa and Festuca iberica and meadows in streams with Carex distans were described. This vegetation contact with thorny shrublands of Berberis hispanica and juniper lands of Juniperus communis subsp. hemisphaerica; in intrazonal soils, contact scree vegetation with Achnatherum calamagrostis and Ligusticum lucidum. C. lepidocarpa and A. calamagrostis are new records to the southern tip of the Iberian Peninsula. S. argentea meadows, the micro-"borreguil" and scree vegetation are Southern European limit for their respective association, class and alliance. [ABSTRACT FROM AUTHOR]

Development of historic vegetation growth curves for both grasslands and shrublands in Mexico becomes a real challenge due to lack of statistics. Remote sensing technology using satellites, allows obtaining a first approximation through vegetation indices (VI). The present study discusses an indirect parametric modeling of the biomass growth curve in individual pixels of both Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS), thus allowing their characterization using pre and post process algorithms. Results obtained through application of the algorithms discussed in the present paper, allow obtaining annual growth curves at 100 ha (AHVRR) and 6.25 ha (MODIS) scales that can be used in studies on climate change and on grassland/shrubland management in Mexico. [ABSTRACT FROM AUTHOR]

A study of the diversity of legumes in the northern part of the state of Nuevo León was undertaken. 38 genera, 94 species and 26 infraspecific taxa of legumes were recorded. The family Fabaceae comprises 18 genera and 42 species, Mimosaceae 10 and 30 and Caesalpiniaceae 10 and 22 respectivelly. The genera with highest number of species are Acacia (12), Dalea (10), Mimosa (6), Senna (5), Caesalpinia (4) and Bauhinia (4). Shrubby legumes are the most abundant in the zone, representing 47% (46 species); the herbaceous ones constitute 46% (45) and the arboreal ones comprise 7% (7). The highest number of taxa was recorded on semithorn shrubland (52) piedmont scrub (48), oak-pine forest (44), while the mezquite shrublands shelter the lowest number of species (23). [ABSTRACT FROM AUTHOR]

A review is made of the endemic plants following the Megacoahuila concept, that increases the state area for more than 100%. The region has climatic and physiographic variation that leads to the development of at least 13 main vegetation types, the desert shrubland being the dominant one. A total of 350 species and infraspecific taxa are listed, representing 11.2% of the total flora. The desert shrubland (matorrales micrófilo y rosetófilo) is the vegetation with the highest endemism and the Cuatro Cienegas basin the richest locality. The areas with highest endemism are suggested to be considered biotic reserves. [ABSTRACT FROM AUTHOR]

Ipomoea rzedowskii is described as a new species to science, from the Mexican states of Guanajuato, Hidalgo and Querétaro. This white flowered shrub grows in xerophilous shrublands on steep slopes east of Xichú and in the canyons of Estórax, Moctezuma and Tolimán rivers. This new taxon belongs to the series Arborescentes. [ABSTRACT FROM AUTHOR]