Implicaciones metodológicas e inconsistencias de la Tercera Comunicación Nacional sobre Cambio Climático de Colombia

Las Comunicaciones Nacionales sobre Cambio Climático (CNCC) son un mecanismo para que los países informen sus avances en mitigación y adaptación, y constituyen uno de los elementos de base para la política sobre cambio climático a escala nacional. Colombia ha emitido tres CNCC. La tercera plantea un escenario que considera las proyecciones de diversos modelos incluidos en la quinta fase del Proyecto de Comparación de Modelos Acoplados (Coupled Model Intercomparison Project, CMIP), el cual se estima como el promedio de las proyecciones correspondientes a las cuatro trayectorias de concentración representativa (Representative Concentration Pathways,RCP) presentadas en el quinto reporte de evaluación del Panel Intergubernamental sobre Cambio Climático. Cada una de estas RCP representa una trayectoria de concentración de gases de efecto invernadero (GEI) para un escenario particular de crecimiento poblacional, económico y tecnológico que conduce a una posible trayectoria de evolución del sistema climático. En este estudio se comparan las proyecciones presentadas en la Tercera CNCC con las obtenidas directamente de los modelos empleados. Nuestros resultados demuestran que al utilizarse un promedio de RCP se pierden escenarios alternos que podrían ser importantes a la hora de considerar posibles futuros diferentes y anulan la utilidad de plantear diversas trayectorias de emisiones de GEI. Más aun, una comparación entre la Segunda y la Tercera CNCC muestra proyecciones de precipitación opuestas para diferentes regiones del país, lo cual es de particular importancia, pues el escenario de cambio climático planteado en la Tercera CNCC sirve de referencia para la toma de decisiones en materia de cambio climático a nivel nacional

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Effects of Amazonian Dark Earths on growth and leaf nutrient balance of tropical tree seedlings

Background and aims: Amazonian Dark Earths (ADE) are ancient anthropogenic soils distributed in the Amazon basin. They are characterized by high nutrients such as phosphorus, calcium, potassium and nitrogen. We studied the effect of ADE on growth, morphology and physiology of 17 tree species from a Bolivian tropical moist forest.MethodsWe conducted a greenhouse experiment where seedlings were grown for 2–4 months on ADE and non-ADE. We evaluated soil nutrient concentrations, seedling growth, leaf and root functional traits, and leaf nutrient concentrations.ResultsSoil type affected 10 out of 24 evaluated seedling traits. Seedlings did not invest more in roots in non-ADE, but they invested in leaves and leaf area in ADE, although this did not lead to faster growth rate. Species responded differently to soil Ca increment; some species seemed to suffer from Ca toxicity as indicated by low survival, others from nutrient imbalance, whereas other species increased their leaf calcium, phosphorus and nitrogen concentration in ADE. Only for this latter group of nutrient accumulators, there was a positive interspecific relationship between leaf Ca and seedling growth rates.ConclusionsADE did not lead to increased seedling growth. The ability of plants to colonize patches of ADE might depend on plant responses to increased soil Ca and their capacity to regulate internal tissue calcium to balance nutrition

Morichales, cananguchales y otros palmares inundables de Suramérica. Parte II: Colombia, Venezuela, Brasil, Perú, Bolivia, Paraguay, Uruguay y Argentina

El libro está dividido en cuatro partes. En la primera sección se incluye un análisis muy completo sobre el estado del conocimiento, uso y conservación de Mauritia flexuosa en Suramérica. En la segunda parte se consideran varios casos de estudio (11) sobre comunidades de plantas asociadas, demografía, polinizadores, aves y mamíferos relacionados, así como temas de manejo y ecoturismo en palmares de Mauritia flexuosa. La tercera sección incluye aportes de varios países sobre otros palmares, principalmente de Astrocaryum jauari, Butia odorata, B. paraguayensis, Copernicia alba, C. tectorum, Euterpe oleracea, Manicaria saccifera, Mauritiella aculeata y Roystonea oleracea. También se aporta información de 25 especies adicionales de palmas, incluyendo los usos, dinámica de poblaciones, biología reproductiva, florística de humedales asociados y conservación, entre otros aspectos. Por último, en la cuarta parte se dan las conclusiones y recomendaciones para la conservación de los palmares inundables en Suramérica.Bogotá, D. C

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale