Contribution of integrated water resources management towards the achievement of the Millennium Development Goals (MDGs)

Published by Asociación de Economistas Agrarios de Chilewater and the millennium development goals, Millennium Development Goals, integrated water resources management, water resources and development., Environmental Economics and Policy, Political Economy, Public Economics,

The macroecology of chemical communication in lizards: do climatic factors drive the evolution of signalling glands?

Chemical communication plays a pivotal role in shaping sexual and ecological interactions among animals. In lizards, fundamental mechanisms of sexual selection such as female mate choice have rarely been shown to be influenced by quantitative phenotypic traits (e.g., ornaments), while chemical signals have been found to potentially influence multiple forms of sexual and social interactions, including mate choice and territoriality. Chemical signals in lizards are secreted by glands primarily located on the edge of the cloacae (precloacal glands, PG) and thighs (femoral glands), and whose interspecific and interclade number ranges from 0 to >100. However, elucidating the factors underlying the evolution of such remarkable variation remains an elusive endeavour. Competing hypotheses suggest a dominant role for phylogenetic conservatism (i.e., species within clades share similar numbers of glands) or for natural selection (i.e., their adaptive diversification results in deviating numbers of glands from ancestors). Using the prolific Liolaemus lizard radiation from South America (where precloacal glands vary from 0-14), we present one of the largest-scale tests of both hypotheses to date. Based on climatic and phylogenetic modelling, we show a clear role for both phylogenetic inertia and adaptation underlying gland variation: (i) solar radiation, net primary productivity, topographic heterogeneity and precipitation range have a significant effect on number of PG variation, (ii) humid and cold environments tend to concentrate species with a higher number of glands, (iii) there is a strong phylogenetic signal that tends to conserve the number of PG within clades. Collectively, our study confirms that the inertia of niche conservatism can be broken down by the need of species facing different selection regimes to adjust their glands to suit the demands of their specific environments

New insights in the global cycle of acetonitrile: release from the ocean and acetonitrile: release from the ocean and Venezuela

International audienceCUsing the proton transfer reaction mass spectrometry (PTR-MS) technique, acetonitrile was measured during the wet season in a Venezuelan woodland savanna. The site was located downwind of the Caribbean Sea and no biomass burning events were observed in the region. High boundary layer concentrations of 211 ±36 pmol/mol (median, ± standard deviation) were observed during daytime in the well mixed boundary layer, which is about 60 pmol/mol above background concentrations recently measured over the Mediterranean Sea and the Pacific Ocean. Most likely acetonitrile is released from the warm waters of the Caribbean Sea thereby enhancing mixing ratios over Venezuela. Acetonitrile concentrations will probably still be much higher in biomass burning plumes, however, the general suitability of acetonitrile as a biomass burning marker should be treated with care. During nights, acetonitrile dropped to levels typically around 120 pmol/mol, which is consistent with a dry deposition velocity of ~0.14 cm/s when a nocturnal boundary layer height of 100 m is assumed

Sobre el Jurásico del Mencal y su relación con otras series sub-béticas de la transversal de Granada

Se describen nuevos términos pertenecientes a la serie jurásica del Mencal (Morrón de la Meseta), junto con otros de un corte próximo a Iznalloz (Granada). Ambas series se correlacionan entre si y con otras series que constituyen un umbral en la cuenca sedimentaria subbética

Influencia del arbolado urbano sobre los niveles de ruido en una ciudad de Chile central

The effect of urban trees as a noise mitigating element was determined on Alameda Avenue in the city of Talca, Chile, a Mediterranean continental area. Maximum and minimum noise, especially generated from vehicles, was recorded at 13 points in four sections of the avenue for twelve days, three times a day at different distances from the edge of the street way, which generated a total of 2,080 noise records. At each point a circular plot of 201 m2 was established to determine tree and shrub coverage. The results showed significant differences of noise between the classes of coverage; however there was no relationship significant between the noise level and the increase in coverage, which can be explained by the large amplitude in the noise registers. The vegetation located at 6.5 meters from the sound source shows lower levels of noise when the coverage is increased, proving the environmental function of the vegetation in the mitigation of this pollutant agent. Regarding theses of the findings, it is necessary to implement public policies that consider urban planning, incorporating in its design greater and better availability of tree species and that certain public space are located away from sources of noise pollution.Se determinó el efecto del arbolado urbano como elemento mitigador del ruido en la avenida Alameda de la ciudad de Talca, Chile, ubicada en el área continental. Se registró durante 12 doce días el ruido máximo y mínimo, especialmente proveniente del tránsito vehicular, en 13 puntos en cuatro secciones de la avenida, en tres horarios durante el día a diferentes distancias del borde de la vía, generándose un total de 2.080 registros de ruido. En cada punto se estableció una parcela circular de 201 m2 para determinar la cobertura arbórea y arbustiva. Los resultados mostraron diferencias significativas entre las clases de cobertura, sin embargo no se observó una relación significativa entre el nivel de ruido y el aumento de la cobertura, lo que se puede explicar por la gran amplitud en los registros de ruido. La vegetación ubicada a 6,5 metros de la fuente sonora muestra menores niveles de ruido cuando se incrementa la cobertura vegetal, comprobando la función ambiental de la vegetación en la mitigación de este contaminante. En consideración a los hallazgos, es necesario implementar políticas públicas que consideren una planificación urbana que incorpore en su diseño mayor y mejor disponibilidad de especies arbóreas y que ciertos espacios públicos, como el estudiado, se localice alejado de las fuentes de contaminación acústica.Fil: Calquín P., Felipe. Corporación Nacional Forestal (Chile)Fil: Ponce-Donoso, Mauricio. Universidad de Talca (Chile)Fil: Vallejos-Barra, Óscar. Universidad de Talca (Chile)Fil: Plaza T., Exequiel. Universidad de Talca (Chile

Influence of urban trees on noise levels in a central Chilean city

The effect of urban trees as a noise mitigating element was determined on Alameda Avenue in the city of Talca, Chile, a Mediterranean continental area. Maximum and minimum noise, especially generated from vehicles, was recorded at 13 points in four sections of the avenue for twelve days, three times a day at different distances from the edge of the street way, which generated a total of 2,080 noise records. At each point a circular plot of 201 m2 was established to determine tree and shrub coverage. The results showed significant differences of noise between the classes of coverage; however there was no relationship significant between the noise level and the increase in coverage, which can be explained by the large amplitude in the noise registers. The vegetation located at 6.5 meters from the sound source shows lower levels of noise when the coverage is increased, proving the environmental function of the vegetation in the mitigation of this pollutant agent. Regarding theses of the findings, it is necessary to implement public policies that consider urban planning, incorporating in its design greater and better availability of tree species and that certain public space are located away from sources of noise pollution.The effect of urban trees as a noise mitigating element was determined on Alameda Avenue in the city of Talca, Chile, a Mediterranean continental area. Maximum and minimum noise, especially generated from vehicles, was recorded at 13 points in four sections of the avenue for twelve days, three times a day at different distances from the edge of the street way, which generated a total of 2,080 noise records. At each point a circular plot of 201 m2 was established to determine tree and shrub coverage. The results showed significant differences of noise between the classes of coverage; however there was no relationship significant between the noise level and the increase in coverage, which can be explained by the large amplitude in the noise registers. The vegetation located at 6.5 meters from the sound source shows lower levels of noise when the coverage is increased, proving the environmental function of the vegetation in the mitigation of this pollutant agent. Regarding theses of the findings, it is necessary to implement public policies that consider urban planning, incorporating in its design greater and better availability of tree species and that certain public space are located away from sources of noise pollution

Sobre el Jurásico del Mencal y su relación con otras series sub-béticas de la transversal de Granada

Se describen nuevos términos pertenecientes a la serie jurásica del Mencal (Morrón de la Meseta), junto con otros de un corte próximo a Iznalloz (Granada). Ambas series se correlacionan entre si y con otras series que constituyen un umbral en la cuenca sedimentaria subbética