Influencia del micrositio y el ambiente en la instalación de Polylepis tarapacana en los Altos Andes

Del total de micrositios presentes en un ambiente, solo una fracción presenta condiciones adecuadas para asegurar la regeneración del bosque. Este estudio analiza la facilitación dada por el ambiente y los micrositios a la regeneración de P. tarapacana en los Altos Andes. Se trabajó con 21 bosques en Jujuy, Argentina, registrándose variables de estructura forestal, humedad de suelo y la oferta de micrositios para la instalación de renovales. Se realizó un análisis de correlación de Pearson entre variables ambientales y de estructura forestal de renovales y de árboles y arbustos. Además, se realizó un ANOVA simple utilizando 8 categorías de micrositios como factor principal para analizar la humedad del suelo y la densidad de renovales. La densidad de renovales representa el 36.8% de la densidad de árboles y arbustos. A mayores pendientes la presencia de renovales disminuye, pero no se hallaron diferencias significativas con la altitud. Se encontró una mayor densidad de plántulas (201.2 y 279.5 ind.ha−1) en micrositios bajo la influencia de rocas que coindicen con una mayor humedad de suelo, pero no así en micrositios con hojarasca, con un mismo contenido de humedad. Existió una oferta variada de micrositios posibles de encontrar en la zona de estudio, donde la densidad de los renovales se relacionó positivamente con la oferta de micrositios bajo la influencia de rocas, y estuvo asociada a la humedad relativa de los mismos. Estos resultados permiten definir los micrositios propicios para la regeneración de P. tarapacana pudiendo ser utilizados para identificar las áreas más adecuadas para la restauración y conservación de esta especie.Of the total numbers of microsites present in an environment, only a fraction presents adequate conditions to ensure the regeneration of the forest. This study analyzes the facilitation given by the environment and the microsites in the P. tarapacana regeneration in the High Andes. We worked with 21 forests in Jujuy, Argentina, registering variables of forest structure, soil moisture and the offer of microsites. Pearson correlation analyses were done between environmental variables and forest structure of seedling and trees and shrubs. In addition, a simple ANOVA were performed using 8 categories of microsites as the main factor to analyze soil moisture and the density of seedling. The density of seedling represents 36.8% of the density of trees and shrubs. At greater slopes, the presence of seedling decreases, but no significant differences were found with altitude. A higher seedling density (201.2 and 279.5 ind.ha−1) was found in microsites under the influence of rocks that coincide with higher soil moisture, but not in microsites with litter, with the same moisture content. There was a varied offer of microsites that could be found in the study area, where the density of the seedling was positively related to the offer of microsites under the influence of rocks and was associated with their relative humidity. These results define microsites favorable for regenerating P. tarapacana which can be used to identify the most suitable areas for restoration and preservation of this species.Fil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Cuyckens, Griet An Erica. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias. Centro de Estudios Ambientales Territoriales y Sociales; Argentin

Optimal environmental drivers of high-mountains forest: Polylepis tarapacana cover evaluation in their southernmost distribution range of the Andes

The Andes Mountains are considered a global biodiversity hotspot, where Polylepis forests are one of the most threatened forests in the area. We evaluate the P. tarapacana forest's distribution and cover and relate this pattern with topographic, climatic and geographic environmental factors at the landscape level. Along 93 plots, forest structure data was conducted according to their homogeneity, accessibility, and size (patches up to > 1 ha each). Hexagon binning processes were used to estimate the forest cover, as the proportion of hexagon area covered by forests, and one-way ANOVAs were conducted to evaluate its variation according to the environmental factors. Our results show that P. tarapacana forests are widely distributed, occupying a forest area of 8519.8 ha among 2462 forest patches and an average of 6.7% of forest cover (1296 hexagons - 129600 ha). According to the findings, the entire forest distribution encompasses a wide range of environmental conditions. We identify that the slopes and elevations were the main environmental drivers that shaped P. tarapacana distribution and cover. Variations in forest area and cover indicate a strong preference for north and east-facing slopes (18 and 24°) and intermediate elevations (4400 - 4500 m a.s.l), with a life zone of Tropical subalpine dry scrub accounting for 62.1%. Our research shows that remote sensing mapping and geographic information systems are effective methods for identifying habitat variables linked to threatened forest cover and evidence of forest vulnerability in the face of continuous global change.Fil: Lopez, Victoria Lien. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Huertas Herrera, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rosas, Yamina Micaela. Universidad de Copenhagen; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentin

Germination of high Andean treeline species of contrasting environments and along elevational gradients in northwest Argentina

In mountain ecosystems, temperature and precipitation change along elevation and determine the lower and upper limits of tree species which form forests. Early life performance of tree species has been assessed along elevational gradients as a proxy for several environmental variables. Here, we attempt to answer the following question: How does elevation provenance influence seed mass, viability, and germination of Queñoa (Polylepis spp.)? We worked with four species from two contrasting environments from northwest Argentina. We gathered seeds along elevation gradients, seeds were weighed, tested for viability (Triphenyltetrazoliumchlorid; TTC) and germination percentage in a controlled environment. The analysis was performed using Generalized Linear Models (GLM). We found low germination percentages in all species, probably related to low seed viability. The two species from humid environments had lower seed mass and higher germination percentages than the two species from dry environments. The effect of elevational provenance negatively affected the germination of two species, while the other two species were not affected. We conclude that although the four species studied belong to the same genus, their early life characteristics differ between environments and along elevational gradients according to species. Trends regarding future temperatures suggest increases in germination for two of our study species and no effects on the other two species.Fil: Cuyckens, Griet An Erica. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Hensen, Isabell. Martin Luther Universität; AlemaniaFil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; ArgentinaFil: Renison, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin

Vertical and horizontal structure in two Polylepis tarapacana forests with different environmental conditions

En la Provincia fitogeográfica Altoandina en Salta y Jujuy, la vegetación es estructuralmente homogénea y poco diversa, donde la queñoa, Polylepis tarapacana, es la única especie que presenta porte arbóreo. Identificar los cambios en la composición y estructura forestal es importante para conocer cómo estos bosques responden a gradientes ambientales, lo cual puede ser útil para plantear estrategias de restauración y conservación de la biodiversidad, entre otras cosas. Se comparó la estructura vertical y horizontal en dos bosques de P. tarapacana en Granadas (G) a 4747,6 ms.n.m y Laguna Larga (LL) a 4610,9 ms.n.m en Jujuy, Argentina. Los resultados sugieren una mayor ocupación y desarrollo del sitio G en relación a LL. Para los sitios estudiados, un aumento en la altura promedio de árboles presentó una relación positiva con la densidad, manteniendo el porcentaje de renovales similar en ambas zonas (735 n.ha-1 en G y 731 n.ha-1 en LL). Ambos sitios mostraron gran cantidad de suelo desnudo y rocas. Es necesaria la continuación de estudios sobre la estructura de estos bosques y su relación con características ambientales, para comenzar a entender su ecología.In the Altoandina phytogeographic province in Salta and Jujuy vegetation is structurally homogeneous and low diverse; the queñoa, Polylepis tarapacana, is the only species that presents arboreal size. Identifying changes in forest composition and structure is important to know how they respond to environmental gradients, which may be useful to set restoration and biodiversity conservation strategies, between other things. In this study, vertical and horizontal structure is compared in two forests of P. tarapacana with contrasting environmental differences in an environmental gradient. Plots were installed in Granadas (G) at 4747.6 masl and Laguna Larga (LL) at 4610.9 masl in Jujuy, Argentina, with contrasting environmental differences where the vertical and horizontal structure were surveyed, presenting values that suggest a greater occupation and development of site G in relation to LL. For the studied sites, an increase in average tree height shows a positive relationship with density, maintaining the similar percentage of renewals in both zones (735 n.ha-1 in G and 731 n.ha-1 in LL). Both sites show a high percentage of bare soil and rocks. It is necessary to continue studies on the structure of these forests and their relationship with environmental characteristics, in order to begin to understand their ecology.Fil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Pérez Flores, Magalí. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Investigación en Sistemas Ecológicos y Ambientales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Sharry, Sandra Elizabeth. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentin

Bud mark count to estimate age in Polylepis tarapacana: A potential technique

En las especies forestales que presentan un crecimiento determinado, las yemas generan marcas que se usan para estimar las edades a lo largo de brotes apicales o de ramas, mediante el conteo de entrenudos. Para estimar la edad a lo largo de las ramas en especies amenazadas y de crecimiento lento, como es el caso de Polylepis tarapacana Phil., es crucial contar con técnicas no destructivas que eviten colectar ramas, renovales o ejemplares completos. Por lo tanto, el objetivo de este trabajo fue evaluar la potencialidad de la técnica de estimación de la edad que utiliza las marcas externas a lo largo de la rama en P. tarapacana. Se trabajó con 13 ramas apicales colectadas en 13 bosques de la localidad de Lagunillas del Farallón, Dto. de Rinconada. En cada una de las ramas se realizó el conteo de marcas de brotes utilizando dos métodos: a) a lo largo de los 20 cm de longitud de la rama principal y b) en un brote lateral de la rama principal, se contaron tres marcas a lo largo del brote. Se analizó si el conteo de marcas se ajusta a la edad con un modelo linear generalizado mixto (Glmm), incluyendo el factor aleatorio árbol (n=26). Los resultados indican que existe potencial para aplicar esta técnica, pero para generar un modelo confiable sería necesario colectar un mayor número de muestras en futuras investigaciones.In forest species that present a determined growth, the buds generate marks that are used to estimate the ages along the apical shoots or branches, by counting the internodes. In order to estimate the age along the branches in threatened and slow-growing species, such as Polylepis tarapacana Phil., it is crucial to have non-destructive techniques that avoid the collection of branches, sapling or complete specimens. Therefore, the objective of this work was to evaluate the potentiality of the age estimation technique, which uses external marks along the branch in P. tarapacana. We worked with 13 apical branches collected in 13 forests in the town of Lagunillas del Farallón, Dpt. Rinconada. Shoot marks were counted on each branch using two methods: a) along the 20 cm length of the main branch and b) on a lateral shoot of the main branch, three marks were counted along the length of the shoot. It was analyzed if the mark count adjusts to age with a mixed generalized linear model (Glmm), including tree as a random factor (n=26). The results indicate that there is potential for applying this technique, but in order to generate a reliable model, it would be necessary to collect a larger number of samples in future research.Fil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Crisci, Geronimo. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Cuyckens, Griet An Erica. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Advances in technologies for propagation and domestication of plants of economic and environmental interest in Argentina

En el Laboratorio de Estudios de la Madera de la Facultad de Ciencias Agrarias y Forestales de la Universidad Nacional de La Plata, Argentina, se implementa el proyecto de desarrollo tecnológico denominado Métodos y tecnologías de propagación y domesticación de plantas para el desarrollo de una bioeconomía local basada en la biodiversidad. El objetivo del mismo es desarrollar, optimizar y adaptar nuevas metodologías y tecnologías de propagación y conservación de recursos genéticos vegetales para la producción de plantas en nuevo escenario de la bioeconomía nacional. La diversidad está en la base de la bioeconomía, y muchas veces el material vegetal para plantar para diferentes fines es escaso. Las especies contempladas en éste proyecto son: Quercus sp.; Polylepis tarapacana; Prosopis alpataco, Eranthemun pulchelum y Heteropteris angustifolia Griseb. En este trabajo se comunican algunos de los avances alcanzados aplicando diferentes enfoques para la producción de plantas de calidad (semillas, cultivo de tejidos in vitro, macropropagación y plantines en contenedores).The Timber Research Laboratory of the Faculty of Agricultural and Forestry Sciences of the National University of La Plata (LIMAD), Argentina, implements the technological development project called Methods and technologies of plant propagation and domestication for the development of a local bioeconomy based on biodiversity. Its objective is to develop, optimize and adapt new methodologies and technologies for the propagation and conservation of plant genetic resources for the production of plants in a new scenario of national bioeconomy. Diversity is at the base of bioeconomy, and often planting plant material for different purposes is scarce. The species covered by this project are: Quercus sp. (exotic forest); Polylepis tarapacana (native forest); Prosopis alpataco. (multipurpose native forestry), Eranthemun pulchelum and Heteropteris angustifolia Griseb (ornamental species of great potential and use in green roofs). This work communicates some of the progress made by applying different approaches to the production of quality plants (seeds, in vitro tissue culture, macro propagation and seed container planting).Fil: Sharry, E.S.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Weber, C.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Cellini, M.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Boeri, P.. Universidad Nacional de Rio Negro. Sede Alto Valle y Valle Medio.; ArgentinaFil: Roussy, L.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Sceglio, P.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Ramilo, D.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Galarco, S.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentin

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Combination of searches for heavy spin-1 resonances using 139 fb−1 of proton-proton collision data at s = 13 TeV with the ATLAS detector

A combination of searches for new heavy spin-1 resonances decaying into different pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fb−1 of proton-proton collisions at = 13 TeV collected during 2015–2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb, , and tb) or third-generation leptons (τν and ττ) are included in this kind of combination for the first time. A simplified model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confidence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions