Las plantas montañosas no resisten a las invasione/Mountain plants unable to withstand invasions

Un equipo internacional de investigadores ha estudiado la distribución de las especies vegetales en ambientes montañosos. El trabajo confirma que las comunidades de plantas montañosas no son tan resistentes frente a las invasiones de plantas exóticas. Los científicos también alertan de que éstas pueden ser más agresivas en un escenario de calentamiento global.

En 2005, científicos de diferentes centros científicos de España, Alemania, Suiza, Australia, EE UU y Chile crearon la Red de Investigación de Invasiones de Montaña (MIREN) para estudiar la distribución de especies exóticas en ambientes de alta montaña y diseñar experimentos que confirmen la capacidad invasora de ciertas especies en ambientes de alta montaña.

“Estas comunidades de plantas de ambientes alpinos eran consideradas hasta ahora poco vulnerables a este tipo de perturbación ambiental”, señala a SINC José Ramón Arévalo, uno de los autores del estudio, e investigador en el Departamento de Ecología de la Universidad de La Laguna. Sin embargo, sus experimentos ponen de manifiesto “la errónea visión que se tiene sobre esta supuesta protección y resistencia de ambientes montañosos contra las especies invasoras”, añade el experto.

El estudio, publicado recientemente en Frontiers in Ecology and The Environment y que se enmarca dentro MIREN, ha permitido identificar los factores que favorecen la vulnerabilidad que tienen las plantas de estas áreas a las invasiones de otras especies.

Entre otros factores, los científicos destacan la facilidad de llegada de propágulos (modalidad de reproducción asexual en vegetales por la que se obtienen nuevas plantas) debido a la actividad humana, así como el aumento de perturbaciones, la poca resistencia biológica de las comunidades de plantas invadidas, el aumento del transporte entre zonas de alta montaña alejadas, y el estimado según modelos de cambio climático global, “que facilitaría el establecimiento de plantas invasoras también para la reproducción”, manifiesta el ecólogo.

An international research team has studied the distribution of plant species in mountainous environments. The study shows that mountain plant communities are not particularly resistant to invasion by exotic species. The scientists also warn that these may become more aggressive as global warming gets a grip.

In 2005, scientists from various science centres in Spain, Germany, Switzerland, Australia, the United States and Chile created the Mountain Invasion Research Unit (MIREN) in order to study the distribution of exotic species in high mountain species and to design experiments to confirm the invasive capacity of certain species in high mountain environments.

"These plant communities in Alpine environments have until now not been thought particularly vulnerable to this kind of environmental disturbance", José Ramón Arévalo, one of the authors of the study and a researcher at the Department of Ecology of the University of La Laguna, tells SINC. However, the experiments show clearly "that the beliefs about this supposed protection and mountain species' resistance to invasive species is erroneous", he adds.

The study, published recently in Frontiers in Ecology and The Environment, and which is part of the work done by MIREN, has made it possible to identify the factors that make plants in these areas more vulnerable to invasion by other species.

Among other factors, the scientists stress the ease of movement of propagules (plants which can reproduce asexually in order to produce new plants) as a result of human activity and the increase in environmental disturbance, the low levels of biological resistance of invaded plant communities, the increase in transport between high mountain areas that are far apart from each other, and the risks according to climate change models, "which will make it easier for invasive plants to establish themselves and reproduce", the ecologist explains.

Tomado de/Taken from Plataforma SINC español/english

Resumen /Summary

Ain't no mountain high enough: plant invasions reaching new elevations
Frontiers in Ecology and The Environment 7(9): 479-486 (2009)

Aníbal Pauchard, Christoph Kueffer, Hansjörg Dietz, Curtis C Daehler, Jake Alexander, Peter J Edwards, José Ramón Arévalo, Lohengrin A Cavieres, Antoine Guisan, Sylvia Haider, Gabi Jakobs, Keith McDougall, Constance I Millar, Bridgett J Naylor, Catherine G Parks, Lisa J Rew and Tim Seipel

Most studies of invasive species have been in highly modified, lowland environments, with comparatively little attention directed to less disturbed, high-elevation environments. However, increasing evidence indicates that plant invasions do occur in these environments, which often have high conservation value and provide important ecosystem services. Over a thousand non-native species have become established in natural areas at high elevations worldwide, and although many of these are not invasive, some may pose a considerable threat to native mountain ecosystems. Here, we discuss four main drivers that shape plant invasions into high-elevation habitats: (1) the (pre-)adaptation of non-native species to abiotic conditions, (2) natural and anthropogenic disturbances, (3) biotic resistance of the established communities, and (4) propagule pressure. We propose a comprehensive research agenda for tackling the problem of plant invasions into mountain ecosystems, including documentation of mountain invasion patterns at multiple scales, experimental studies, and an assessment of the impacts of non-native species in these systems. The threat posed to high-elevation biodiversity by invasive plant species is likely to increase because of globalization and climate change. However, the higher mountains harbor ecosystems where invasion by non-native species has scarcely begun, and where science and management have the opportunity to respond in time.

El fracaso de la Cumbre de Copenhague/The failure of the Copenhagen Summit

La cumbre de Copenhage se cierra con una sensación de fracaso. El papel preponderante de China y EEUU, el llamado G2, se ha vuelto a poner de manifiesto.
El Acuerdo final, negociado entre EEUU, China, India, Sudáfrica y Brasil, sólo reconoce la necesidad de contener el aumento de la temperatura media del planeta en dos grados, un umbral por encima del cual los efectos podrían ser irreversibles. No especifica cuál es el punto máximo en que deben empezar a descender las emisiones, sólo dice "lo antes posible" cuando los científicos marcan 2015 como el límite de "no retorno".
Promete una inversión de 30.000 millones de $US en ayuda a los países en desarrollo a lo largo de los próximos tres años y establece el objetivo de llegar a los 100.000 millones $US anuales para 2020.
Se trata de un acuerdo con un grado de concreción menor que el del Protocolo de Kioto, a pesar de que la situación es ahora mucho más preocupante que hace una década.

The Copenhagen Climate summit closed with a failure sensation. The preponderant role played by China and USA, the G2, has been shown again.
The final Accord, negotiated in fact between USA, China, India, South Africa and Brazil, only recognizes the necessity to contain the increase of the average temperature of the planet in two degrees, a threshold over which the effects could be irreversible. The maximum point in which the emissions must begin to descend is not specified, "as soon as possible" it is said, when the scientists have marked year 2015 as the no-return limit.
An investment of 30 billion dollars to help the developing countries throughout the next three years is promised, as well as the goal to jointl mobilize 100 billion dollars a year by 2020.
This is an Accord with a samller degree of concretion than the achieved in Kyoto 1997, although the situation is now much more worrisome.

Texto del Acuerdo (en inglés)/Text of the Accord

El impacto que mató a los dinosaurios solo gratinó la Tierra/Dinosaur-killing impact only set Earth to broil

Un nuevo estudio parece sugerir que el asteroide que impactó hace 65 millones de años acabando con la vida de los dinosaurios, no incineró la vida sobre la superficie del planeta, sino que simplemente la "gratinó". El trabajo responde algunas preguntas preocupantes acerca de la teoría que sostiene que el impacto produjo incendios mortales en todo el mundo, pero origina nuevas cuestiones acerca de lo que realmente condujo a la extinción masiva de fines del periodo Cretácico.
La extinción de los dinosaurios y de la mayoría de las especies del planeta, se achaca al impacto de un asteroide de 10 km de diámetro. Los primeros modelos por computador demostraron que más de la mitad de los residuos llevados al espacio por el impacto, volverían a la atmósfera a las ocho horas.
Los modelos predijeron que esa lluvia de residuos calientes irradiaría, entre 20 minutos y dos horas, el mismo calor de un horno cuando "gratina" (260ºC). Este calentamiento intenso y durante tanto tiempo, llevaría la madera al punto de ignición originando incendios a nivel global.
Sin embargo, algunas especies sobrevivieron y el estrato con los restos del impacto no contiene tanta ceniza como cabría esperar de la quema de todos los bosques del mundo, lo que hace cuestionarse acerca de la magnitud de los incendios post-impacto.
Para explicar esta discrepancia, Tamara Goldin de la Universidad de Viena y Jay Melosh del Purdue Institue de Indiana, han estudiado como la caida de las eyecciones a través de la atmósfera podría afectar a la transferencia de calor desde lo alto de la atmósfera a la superficie terrestre. Los primeros modelos solo tenían en cuenta a los gases de efecto invernadero como absorbentes del calor.
El estudio revela que los primeros restos que volvieron a entrar en la atmósfera a los pocos minutos del impacto, ayudaron a proteger la superficie terrestre de residuos posteriores. Según dijo Goldin a New Scientist, "las mismas eyecciones se pusieron en medio de la radiación térmica (en la atmósfera) y protegieron la Tierra".
Como resultado, la superficie sufrió un intenso calor procedente del cielo durante unos pocos minutos. Según fueron cayendo más partículas, bloquearon más y más el calor que venía de arriba, impidiendo que los bosques ardieran. De acuerdo a Goldin "es realmente dificil comenzar una ignición con un pulso corto de calor intenso" en un área lejos de la zona del impacto.
La vida sobre la superficie podría haberse gratinado, pero no quedó como una "patata frita". Los animales que consiguieron refugiarse bajo tierra o en el agua, podrían haber sobrevivido a ese corto periodo de intenso calor, lo que explicaría el que no toda la vida muriera.
Wendy Wolbach de la DePaul University en Chicago, que propuso en 1985 que la ceniza hallada a fines del cretáceco provenía de incendios globales, está de acuerdo. Según dijo a the The New Scientist, el efecto apantallador "tiene sentido".
No obstante, sin incendios globales se necesitan otros mecanismos para explicar la extinción masiva. Entre ellos está la idea de que el polvo atmosférico interceptó la radiación solar originando un "invierno del impacto" que duró años hasta que las emisiones posteriores al impacto produjeran un calentamiento global.
La lluvia ácida que siguió al impacto, también podría haber jugado su papel en la extinción, al igual que el estress climático originado por las masivas erupciones volcánicas que tuvieron lugar hace 65 millones de años en la región india del Deccan .

The asteroid impact that ended the age of dinosaurs 65 million years ago didn't incinerate life on our planet's surface – it just broiled it, a new study suggests. The work resolves nagging questions about a theory that the impact triggered deadly wildfires around the world, but it also raises new questions about just what led to the mass extinction at the end of the Cretaceous period.
The impact of a 10-kilometre asteroid is blamed for the extinction of the dinosaurs and most other species on the planet. Early computer models showed that more than half of the debris blasted into space by the impact would fall into the atmosphere within eight hours.
The models predicted the rain of shock-heated debris would radiate heat as intensely as an oven set to "broil" (260 °C) for at least 20 minutes, and perhaps a couple of hours. Intense heating for that long would heat wood to its ignition temperature, causing global wildfires.
Yet some species survived, and the global layer of impact debris doesn't contain as much soot as would be expected from burning the world's forests, raising questions about the extent of post-impact wildfires.
To explain the discrepancy, Tamara Goldin of the University of Vienna and Jay Melosh of Purdue University in Indiana studied how ejecta falling through the atmosphere might affect heat transfer from the top of the atmosphere to the ground. Earlier models considered only how atmospheric greenhouse gases would absorb heat.
The study reveals that the first debris to re-enter the atmosphere just a few minutes after the impact helped protect the surface from the debris that followed. "The actual ejecta themselves were getting in the way of the thermal radiation [in the atmosphere] and shielding the Earth," Goldin told New Scientist.
As a result, the surface felt the full heat from the sky for only a few minutes. As more particles drifted down, they blocked more and more of the heat from above, preventing the world's forests from igniting. "With the short pulse [of intense heat], it's really hard to get ignition" far from the impact site, Goldin says.
Surface life would have been broiled, but not burnt to a crisp. Animals that were able to take refuge underground or in the water were likely able to survive the short period of intense heat, explaining why not all life was killed.
Wendy Wolbach of DePaul University in Chicago, who in 1985 proposed that soot found at the end of the Cretaceous came from global wildfires, agrees. The heat shielding effect "makes sense", she told New Scientist.
Without global wildfires, other mechanisms are needed to explain the mass extinction. These include the idea that dust in the atmosphere cut off sunlight in an "impact winter" that lasted for years before emissions released after the impact caused long-term global warming.
Acid rain following the impact may also have played a role in the extinction, as could the additional stress on global climate from the massive volcanic eruptions that occurred 65 million years ago in India's Deccan Traps.

Tomado de/Taken from New Scientist

Resumen de la publicación/Abstract of the paper
Self-shielding of thermal radiation by Chicxulub impact ejecta: Firestorm or fizzle?
Tamara J. Goldin and H. Jay Melosh1
Geology 37 (2009) 1135-1138
Abstract As hypervelocity ejecta from the Chicxulub (Yucatán, Mexico) impact fell back to Earth, the surface may have received a deadly dose of thermal radiation sufficient to ignite global wildfires. Using a two-phase fluid flow code, which includes ejecta and air opacities in a radiative transfer calculation, we modeled the atmospheric reentry of spherules arriving at distal sites. The models predict a pulse of thermal radiation at the surface peaking at 5–15 kW/m2, analogous to an oven set on “broil” (~260° C). Previous calculations, which ignored spherule opacity, yielded >10 kW/m2 sustained over >20 min and such an extended pulse is thought to be required for wood ignition. However, the new modeling suggests that fluxes only exceed the solar norm for ~30 min and are only >5 kW/m2 for a few minutes. Previous models failed to consider the self-shielding effect of settling spherules, which block an increasing proportion of downward thermal radiation emitted by the later-arriving spherules. Such self-shielding may have prevented widespread wildfire ignition, although the thermal pulse may have been sufficient to ignite localized fires and kill fauna lacking temporary shelter. An opaque cap of submicron dust in the upper atmosphere could, however, override the self-shielding effect.

Un tratado para limitar otros contaminantes de efecto invernadero/A treaty adressed to other greenhouse pollutants

Cuando los líderes mundiales se encuentren en Copenhage en diciembre, para firmar un tratado limitando las emisiones de dióxido de carbono, deberían comenzar a preparar una cumbre futura para tratar sobre otros contaminantes, desde el hollín al ozono, que aunque no permenecen en la atmósfera tanto tiempo como el dióxido de carbono, también contribuyen en gran manera al calentamiento global.

Investigadores del Grupo de Energía y Recursos de la Universidad de California en Berkeley, han estudiado los efectos de contaminantes a corto plazo como el hollín, que permanecen en la atmósfera un tiempo entre días y semanas; contaminantes a medio plazo como el metano que duran una década en el aire, y gases de efecto invernadero como el dióxido de carbono o el óxido nitroso, que dañarán al planeta durante siglos. Se ha demostrado que, en un período de 20 años, las emisiones de contaminantes a corto y medio plazo, han constituido más de la mitad de la contribución humana al calentamiento global.

El hollín y el ozono son contaminantes de efecto invernadero muy conocidos, pero los científicos y los políticos han dirigido sus esfuerzos contra los pesos pesados: el dióxido de carbono y, en menor extensión, el metano, que son los que históricamente han tenido un mayor impacto sobre el calentamiento global. En particular, los efectos del CO2 han alarmado a los científicos y a la opinión pública mundial, ya que su concentración actual en la atmósfera, 386 partes por millón, es la más alta en los últimos 100.000 años y continúa en aumento.

Según la investigadora Stacy C. Jackson, "necesitamos dos tratados diferentes. Es necesario un tratado sobre los contaminantes a corto y medio plazo que tenga una estructura dinámica, puesto que seguén vayamos conociendo más, sabremos si es preciso acalerar los esfuerzos de mitigación que influyan sobre el clima a corto plazo"


When world leaders meet in Copenhagen in December to hash out a treaty limiting carbon dioxide emissions, they should begin planning a future summit to address other pollutants -- from soot to ozone -- that don't remain in the atmosphere as long as carbon dioxide, but nevertheless are major contributors to global warming.

Researchers from the Energy & Resources Group at UC Berkeley, have studied the effects of short-lived pollutants like soot that stay in the atmosphere from days to weeks; medium-lived pollutants like methane that may remain airborne for a decade; and the long-lived greenhouse gases such as carbon dioxide and nitrous oxide, which will plague the planet for centuries. Over a 20-year window, the short- and medium-lived emissions make up over half the human contributions to global warming.

Pollutants like soot and ozone are well-known greenhouse pollutants, but scientists and policy makers have focused most of their attention on the gorillas in the room: carbon dioxide and, to a lesser extent, methane -- pollutants that have had the biggest historical impact on global warming. CO2's long-term effects, in particular, have alarmed scientists and the public, since the level of CO2 in the atmosphere now -- 386 parts per million -- is already higher than it has been in the past 100,000 years, and continues to rise.

According to the scientist Stacy C. Jackson, "we need two separate treaties," she said. "A treaty on short- and medium-lived pollutants should have a dynamic framework, because as we learn more, it will become obvious whether it's necessary to accelerate near-term mitigation efforts to influence near-term climate."

Comunicación científica /Scientific communication
Science 23 October 2009: vol 326, pp. 526 - 527
DOI: 10.1126/science.1177042
Parallel Pursuit of Near-Term and Long-Term Climate Mitigation
Stacy C. Jackson
It is well accepted that reduction of carbon dioxide (CO2) emissions is the lynchpin of any long-term climate stabilization strategy, because of the long lifetime of CO2 in the atmosphere. However, a focus on CO2 may prove ineffective in the near term without comparable attention to pollutants with shorter lifetimes

Tomado de/Taken from Science Daily - Berkeley News

Tierras agrícolas abandonadas para introducir el lince ibérico/Abandoned agricultural land to reintroducing Iberian Lynx

Científicos españoles han desarrollado un modelo que determina las zonas agrícolas con mayor potencial de restauración para la mejora del hábitat del lince ibérico (Lynx pardinus), en peligro de extinción. El estudio demuestra que los olivares de baja producción cercanos al Parque Natural de la Sierra de Cardeña y Montoro (Córdoba), único lugar con Doñana donde habita esta especie, son las más adecuadas.

Investigadores del Instituto de Investigación y Formación Agraria y Pesquera de la Junta de Andalucía (IFAPA) han analizado el impacto y el riesgo de abandono de los olivares de montaña para proponer un tipo de gestión (convencional, integrada o ecológica) de este tipo de plantaciones, o su reconversión al bosque mediterráneo.

El riesgo de abandono de los olivares “se debe a su localización, con graves implicaciones socioeconómicas (principalmente de abandono de la población de las zonas rurales) y ambientales (erosión y riesgo de incendios)”, explica a SINC Manuel Arriaza, director del trabajo e investigador del IFAPA. “A pesar de ser olivares de baja producción y altos costes de producción estas zonas tienen un alto valor medioambiental”, añade Arriaza.

La investigación, que se ha publicado recientemente en el Spanish Journal of Agricultural Research, ha desarrollado el modelo general a partir de varios ‘Sistemas de Información Geográfica’ (SIG), y ha considerado, además, la opinión de expertos sobre las funciones comerciales y no comerciales de los olivares, así como la de 480 personas de la provincia de Córdoba sobre la importancia que la sociedad otorga a estas funciones en estas zonas agrícolas.

Los científicos evaluaron las funciones socioeconómicas (producción de aceite de oliva y fijación de la población rural), medioambientales (lucha contra la erosión, prevención de incendios, preservación y mejora de la biodiversidad, con el caso específico del hábitat del lince ibérico), y culturales.




Spanish scientists have developed a model to identify the agricultural areas with the greatest potential for restoring the habitat of the Iberian lynx (Lynx pardinus), which is at risk of extinction. The study shows that olive groves with low production close to the Natural Park of the Sierra de Cardeña y Montoro, in Córdoba - which is the only place, along with Doñana, where this species lives - are the most appropriate sites for this purpose.

Researchers from the regional government of Andalusia's Institute for Agricultural and Fishing Research and Training (IFAPA) have studied the impact and risk of these mountain olive groves being abandoned, in order to come up with an appropriate management system for them (conventional, mixed or organic), or to suggest they should be reconverted to Mediterranean forest.

The risk of these olive groves being abandoned is "due to their location, which has serious socioeconomic implications (mainly in terms of the population leaving rural areas) and environmental ones (erosion and risk of fires)", Manuel Arriaza, director of the study and a researcher at the IFAPA, tells SINC. "Although the olive groves have low production levels and high production costs, they are areas with great environmental value", adds Arriaza.

The general model of the research study, which has been published recently in the Spanish Journal of Agricultural Research, was developed using various Geographical Information Systems (GISs), and also took into account experts' opinions about the commercial and non-commercial functions of the olive groves, as well as those of 480 people in the province of Córdoba about the importance that society places on these functions in agricultural areas.

The scientists evaluated the socioeconomic functions (olive oil production and retention of the rural population), environmental ones (prevention of erosion and fires, conservation and improvement of biodiversity, with special focus on the habitat of the Iberian lynx), and cultural ones.

Tomado de/Taken from Plataforma SINC (English version)

Publicación científica/Research paper
Restoration of abandoned agricultural lands toward habitats for umbrella species
O. Nekhay and M. Arriaza
Spanish Journal of Agricultural Research 2009 7(2), 375-389
Abstract
This study analyzes the suitability of agricultural lands with risk of abandonment for restoration to suitable habitats for animal species of conservation interest. As a case study, the main focus was on olive plantations (Olea europaea L.) of mountainous areas of Southern Spain and the Iberian lynx (Lynx pardinus Temminck, 1827). The method weighs the judgement of experts on the effect of landscape elements on the habitat via an analytic hierarchy process and spots areas most suitable for restoration through geographical information systems. The results suggest that the edge of major agricultural areas and areas with natural vegetation adjacent to the Natural Park of Sierra de Cardeña and Montoro would be most suitable for restoration of the lynx habitat. The precise location of olive groves suitable for restoration are discussed, as revealed by experts’ decision-making processes. The main interest of the study relies on the potential of the method to combine territorial analysis with biological requirements of endangered species to facilitate their dispersal.

El calentamiento del Ártico genera respuestas biológicas peligrosas/Dramatic Biological Responses To Global Warming In The Arctic

Según Eric Post, Profesor Asociado de Biología en la Penn State University de Pensilvania (EEUU), "El Artico, tal como lo conocemos, podría pronto ser cosa del pasado". Post dirige un extenso equipo internacional que ha llevado a cabo estudios
de la respuesta biológica, a nivel de ecosistema, al calentamiento del Artico, durante el 4º Año Polar Internacional, que finalizó en 2008.
Los científicos han encontrado que el aumento medio anual de la temperatura superficial del Artico en los útlimos 150 años, ha originado efectos dramáticos. Así, en los últimos 20 a 30 años, el mínimo estacional de cubierta de hielo ha disminuido 45.000 kilometros cuadrados por año. De manera similar, la cubierta de nieve ha disminuido constantemente, con unos procesos de deshielo y fragmentación cada vez más tempranos y una estación de cultivos cada vez más larga.
"Muchas especies terrestres y marinas están dufriendo las consecuencias adversas del comportamiento humano a latitudes de miles de kilómetros de distancia". Según Post "No importa donde se mire, en el suelo, en el aire o en el agua, veremos señales de cambios rápidos"
El estudio demuestra que muchas especies icono del Ártico que dependen de la estabilidad y permanencia del hielo oceánico están sufriendo consecuencias “devastadoras”. La pérdida de hábitat de hielo polar está causando una caída vertiginosa del número de ejemplares de gaviotas marfil, morsas del Pacífico, focas oceladas, focas de casco, narvales y osos polares
El estudio se publica en el número de Science del 11 de septiembre de 2009

"The Arctic as we know it may soon be a thing of the past," says Eric Post, Associate Professor of biology at Penn State University. Post leads a large, international team that carried out ecosystem-wide studies of the biological response to Arctic warming during the fourth International Polar Year, which ended in 2008.
The scientists found that the increase in mean annual surface temperature in the Arctic over the last 150 years has had dramatic effects. In the last 20 to 30 years, for example, the seasonal minimal sea ice coverage has declined by a staggering 45,000 square kilometers per year. Similarly, the extent of terrestrial snow cover has declined steadily, with earlier melting and breaking up and an earlier start to the growing season.
"Species on land and at sea are suffering adverse consequences of human behavior at latitudes thousands of miles away," declares Post. "It seems no matter where you look -- on the ground, in the air, or in the water -- we're seeing signs of rapid change."
The study shows that many iconic Arctic species that are dependent upon the stability and persistence of sea ice are faring especially badly. Loss of polar ice habitat is causing a rapid decline in the numbers of ivory gull, Pacific walrus, ringed seal, hooded seal, narwhal, and polar bear.
The study is published in the September, 11 issue of the Science magazine

Tomado de/Taken from Plataforma SINC/Science Daily

Resumen de la publicación/Abstract of the paper
Ecological Dynamics Across the Arctic Associated with Recent Climate Change
Eric Post,Mads C. Forchhammer, M. Syndonia Bret-Harte,Terry V. Callaghan,Torben R. Christensen, Bo Elberling, Anthony D. Fox,Olivier Gilg,David S. Hik, Toke T. Høye, Rolf A. Ims, Erik Jeppesen, David R. Klein, Jesper Madsen, A. David McGuire, Søren Rysgaard, Daniel E. Schindler, Ian Stirling, Mikkel P. Tamstorf, Nicholas J.C. Tyler, Rene van der Wal, Jeffrey Welker, Philip A. Wookey, Niels Martin Schmidt, Peter Aastrup
Science 11 September 2009:
Vol. 325. no. 5946, pp. 1355 - 1358
DOI: 10.1126/science.1173113
Abstract
At the close of the Fourth International Polar Year, we take stock of the ecological consequences of recent climate change in the Arctic, focusing on effects at population, community, and ecosystem scales. Despite the buffering effect of landscape heterogeneity, Arctic ecosystems and the trophic relationships that structure them have been severely perturbed. These rapid changes may be a bellwether of changes to come at lower latitudes and have the potential to affect ecosystem services related to natural resources, food production, climate regulation, and cultural integrity. We highlight areas of ecological research that deserve priority as the Arctic continues to warm.

La desnitrificación podría volver a dominar/Denitrification may be back on top

Durante décadas, los científicos han pensado que conocían el funcionamiento del ciclo del nitrógeno, un complicado proceso natural, esencial para el mantenimiento de la vida en la Tierra. El proceso, uno de los juegos de manos más elegantes de la naturaleza, transporta nitrógeno del suelo a los oceános y a la atmósfera y vuelta a trás.
Una etapa clave, se pensaba, era la desnitrificación. En condiciones anaeróbicas como las de los sedimentos oceánicos y en algunas regiones del mar abierto, las bacterias llevan a cabo la importante tarea de transformar los nitratos en gases nitrogenados, que completan el ciclo volviendo a la atmósfera.
En 1995, un grupo investigador holandés, que estudiaba el ciclo del nitrógeno en plantas de depuración de aguas residuales, propusieron un nuevo mecanismo, la oxidación aeróbica o "anammox" que implicaba diferentes bacterias. Demostraron que funcionaba en lodos de depuradora y confirmaron que el mecanismo también lo hacía en ambientes marinos con bajo oxígeno. Llegaron a sugerir que el ciclo del nitrógeno en los océanos debía ser revisado y que la desnitrificación no jugaba un papel tan clave como se pensaba.
La idea era controvertida y no dfue aceptada por muchos científicos.
Ahora, un equipo dirigido por Bess Ward, Professor of Geosciences en la Universidad de Princeton ha presentado datos que pueden restablecer la desnitrificación, y no la anammox como el factor clave para devolver el nitrógeno a la atmósfera.
Los resultados han sido publicados en Nature. Según Ward "en nuestra publicación, reportamos que en el mayorsecosistema marino anóxico mundial, las poco oxigenadas aguas del Mar de Omán (Arabian Sea), el proceso dominante es la desnitrificación y no la anammox.". "Si la denitrificación es importante en el Mar de Omán, también lo es a escala global"
El ciclo del nitrógeno es uno de los más importantes ciclos de nutrientes en la naturaleza. El nitrógeno pasa de la atmósfera y se transforma a una especie que puede ser consumida por las plantas. El nitrógeno constituye casi el 80% de la atmósfera y es utilizxado por los organismos vivos para producir un gran número de moléculas orgánicas complejas, como el ADN.

For decades, scientists thought they had a handle on the workings of an intricate natural mechanism known as the nitrogen cycle, essential to maintaining life on Earth. This process, one of nature's most elegant sleights-of-hand, shuttles nitrogen from the soils to the oceans to the atmosphere and back.
A key part , researchers once thought, was a process known as denitrification. In low-oxygen -- or anaerobic -- conditions seen in large stretches of ocean sediments and in a few important regions of the open ocean, bacteria perform the crucial task of gobbling up nitrates and converting them to nitrogen gases, which complete the cycle by flowing back to the atmosphere.
In 1995, a group of Dutch scientists who had been studying the cycling of nitrogen through wastewater treatment plants came up with a startling conclusion. A new process, which they called anaerobic oxidation or "anammox" and that involved different bacteria, was the real player in removing nitrogen in low-oxygen environments, they said. They found the process worked to break down materials in sewage, and they confirmed that the mechanism also was operating in low-oxygen marine environments. They went so far as to suggest that the nitrogen cycle for oceans needed to be revised, as denitrification, according to their inquiry, did not play the major role that had been thought.
The notion was controversial and did not sit well with some scientists.
Now, a research team, led by Bess Ward, the William J. Sinclair Professor of Geosciences at Princeton University, is presenting data that could re-establish denitrification, and not anammox, as the main actor in returning nitrogen to the air.
The results have been published in Nature. According to Ward, "in our paper, we report that in the world's largest anoxic marine ecosystem -- the low-oxygen waters of the Arabian Sea -- denitrification rather than anammox is the dominant process". "If denitrification is important in the Arabian Sea, then it is important on a global scale."
The nitrogen cycle is one of the most important nutrient cycles in nature, providing a transformative process in which nitrogen is taken from the atmosphere and converted into a form that can be consumed by plants. Nitrogen makes up about 80 percent of the earth's atmosphere. It is used by living organisms to produce a number of complex organic molecules, including DNA.

Tomado de/Taken from Princeton University

Las minas pueden proporcionar enegía geotérmica/Mines could provide geothermal energy

Las galerías de las minas que están a punto de cerrar se pueden aprovechar para que los municipios del entorno obtengan energía geotérmica. Ésta es la conclusión de dos ingenieros de la Universidad de Oviedo, que este mes publican su investigación en la revista Renewable Energy. El método que han desarrollado permite estimar la cantidad de calor que podría aportar una galería.

“Una forma de aprovechamiento de la energía geotérmica de baja intensidad es convertir las galerías de las minas en calderas geotérmicas, que podrían facilitar calefacción y agua caliente a los vecinos del entorno”, explica a SINC Rafael Rodríguez, de la Escuela Técnica Superior de Ingenieros de Minas de Oviedo. Este tipo de energía, que apenas se aprovecha en España, se obtiene a partir del calor del interior de la Tierra.

El ingeniero, junto a su colega María Belarmina Díaz, han desarrollado un método “semi-empírico” (entre matemático y experimental) para calcular la cantidad de calor que podrían proporcionar una galería de una mina que se va a abandonar, a partir de estudios realizados mientras todavía está activa.

El uso de la energía geotérmica también permite reducir las emisiones de CO2 y es independiente de las condiciones climáticas (a diferencia de otras energías renovables como la solar o la eólica). Otras ventajas son que sus instalaciones utilizan recursos propios de un país, no requieren grandes extensiones de terreno, no contaminan el entorno próximo y están consideradas rentables a largo plazo.

La energía geotérmica se puede usar directamente en viviendas unifamiliares, urbanizaciones, piscinas, piscifactorías, naves industriales y otros edificios.

Mine shafts on the point of being closed down could be used to provide geothermal energy to local towns. This is the conclusion of two engineers from the University of Oviedo (Spain), whose research is being published in the journal Renewable Energy. The method they have developed makes it possible to estimate the amount of heat that a tunnel could potentially provide.

"One way of making use of low-intensity geothermal energy is to convert mine shafts into geothermal boilers, which could provide heating and hot water for people living nearby", Rafael Rodríguez, from the Oviedo Higher Technical School of Mining Engineering, tells SINC. This type of energy, which is hardly used in Spain, is obtained from the internal heat of the Earth.

The engineer and his colleague María Belarmina Díaz have developed a "semi-empirical" method (part mathematical and part experimental) to calculate the amount of heat that could be produced by a mine tunnel that is due to be abandoned, based on studies carried out while it is still in use.

Using geothermal energy also helps to reduce CO2 emissions, and is not dependent upon climatic conditions (unlike other renewable energies such as solar or wind power). Other advantages are that these facilities make use of a country's own resources, do not require new developments on large sites, do not pollute the immediate environment, and are believed to be profitable over the long term.

Geothermal energy can be used directly in family homes, housing developments, swimming pools, fish farms, industrial units and other buildings.

Tomado de/Taken from Plataforma SINC/Science Daily

Resumen de la publicación/Abstract of the paper
Analysis of the utilization of mine galleries as geothermal heat exchangers by means a semi-empirical prediction method
Rafael Rodríguez and María B. Díaz, Renewable Energy, 34(7) 1716-1725 (2009)
Abstract
The use of renewable energies in Spain is growing; nevertheless, up to now, a very low use of geothermal energy is found. In this paper, the use of low enthalpy geothermal energy that consists of converting mine galleries in underground heat exchangers is described and analysed. The system would be used in those areas with mining works that with a near future closure, such as Asturias but also other regions of Spain or Europe. The described system, unlike other proposed ones, implies to act before the closure of the mines, when it is possible to access underground galleries. A prediction method for evaluating the system capabilities has been developed which has been calibrated with measurements taken in underground mines and which can be used and calibrated in any mine in operation. Finally, using the method, the capabilities of a typical system are analysed and its viavility from a technical, economic and environmental point of view is proved.

Plumas carbonizadas de gallina para almacenar hidrógeno/Carbonized chicken feathers for hydrogen storing

Científicos de Delaware afirman que han desarrollado un nuevo método para almacenar hidrógeno usando fibras de plumas carbonizadas de gallina, que pueden contener grandes cantidades del gas, una fuente muy prometedora y con un coste mucho más bajo que otros sistemas.
Según P. Wool, Ph.D., Profesor de Ingeniería Química en la Universidad de Delaware in Newark, "Las fibras carbonizadas de pluma de gallina tienen potencial para mejorar de forma dramática los rendimientos de otros métodos de almacenamineto de hidrogeno, y quizás puedan facilitar el camino para el desarrollo práctico de una economía basada en el hidrógeno"
Las fibras de pluma de gallina están compuestas mayoritariamente por queratina, una proteína natural que forma tubos huecos y muy robustos. Al calentarla, la proteína se entrecruza reforzando su estructura, y se vuelve más porosa aumentando su área superficial. El resultado final son fibras carbonizadas de plumas de gallina, que pueden absorber tanto o más hidrógeno que los nanotubos de carbono o los hidruros metálicos, los otros dos materiales que se están estudiando por su potencial para almacenar hidrógeno.
Según Wool, la utilización de estas plumas carbonizadas solo añadiría 140 € al precio de un coche. A modo de comparación, un tanque de combustible de 20 galones (75 litros) de hidrógeno hecho con nanotubos de carbono, costaría 3.800.000 €, mientras que uno con hidruros metálicos costaría 21.000 €.

Scientists in Delaware say they have developed a new hydrogen storage method — carbonized chicken feather fibers — that can hold vast amounts of hydrogen, a promising but difficult to corral fuel source, and do it at a far lower cost than other hydrogen storage systems under consideration.
"Carbonized chicken feather fibers have the potential to dramatically improve upon existing methods of hydrogen storage and perhaps pave the way for the practical development of a truly hydrogen-based energy economy," says Richard P. Wool, Ph.D., professor of chemical engineering at the University of Delaware in Newark.
Chicken feather fibers are mostly composed of keratin, a natural protein that forms strong, hollow tubes. When heated, this protein creates crosslinks, which strengthen its structure, and becomes more porous, increasing its surface area. The net result is carbonized chicken feather fibers, which can absorb as much or perhaps more hydrogen than carbon nanotubes or metal hydrides, two other materials being studied for their hydrogen storage potential.
Using carbonized chicken feathers would only add about $200 to the price of a car, according to Wool. By comparison, making a 20-gallon hydrogen fuel tank that uses carbon nanotubes could cost $5.5 million; one that uses metal hydrides could cost up to $30,000, Wool says.

Tomado de/Taken from Eureka Alert

Resumen de la Comunicación/Summary of the Communication
13th Annual green Chemistry & Engineering Conference
Erman Şenöz , Chemical Engineering Department, University of Delaware, Newark, DE
Richard P. Wool , Chemical Engineering Department, University of Delaware, Newark, DE
The biggest obstacles to a hydrogen powered energy economy are the production and storage of hydrogen. The Department of Energy’s (DOE) 2010 and 2015 hydrogen storage targets are quite challenging in terms of gravimetric capacity (6 wt% and 9 wt% respectively), volumetric capacity (45 and 81 grams H2 per L) and storage cost ($4 and $2 per kWh respectively). In order to solve the H2 storage problem, various kinds of nano-structured materials have been investigated and produced, none of which could fulfill these targets entirely. Their disposal methods and degradability are still a big question mark. Additionally, the prices of these materials are extremely expensive. It is crucial that the material that will serve as a hydrogen adsorbent in fuel cell vehicles is cheap and is environmentally.
The goal of this project is to develop new low cost hydrogen storage substrates from a waste material (6 billion lbs/yr in U.S.) —chicken feathers. The results showed that carbonized chicken feathers (CCFF) have the potential to meet the DOE requirements for H2 storage and are competitive with carbon nanotubes and metal hydrides at a tiny fraction of the cost. When keratin based chicken feathers are heat treated by controlled pyrolysis, hollow carbon microtubes are formed with nanoporous walls. Their specific surface area increases up to 450 m2/g by the formation of fractals and micropores thus enabling more hydrogen adsorption than raw (untreated) feather fibers. Experimental hydrogen storage optimization results and surface characterization of CCFF by SEM, XPS and N2 adsorption will be demonstrated. Furthermore, recent findings on heat treatment of chicken feather fibers by thermal analysis techniques will be discussed in detail.

Los ríos catalanes tienen un problema de acumulación de sedimentos/Catalonian rivers have a problem of accumulation of sediments

Investigadores catalanes han estudiado las nueve cuencas fluviales de Cataluña que desembocan en el Mediterráneo, y han analizado sus características geomorfológicas, climáticas, hidrológicas, de uso del suelo y de sedimentos. La investigación apunta que su descarga sedimentaria al mar ha disminuido en las últimas décadas por la urbanización en las cuencas fluviales, las extracciones de agua, y la retención de los embalses
Aunque es muy difícil cuantificar los factores medioambientales y antropogénicos que afectan a la descarga de sedimentos que los ríos hacen en el mar, un equipo de científicos catalanes ha recopilado datos para caracterizar y evaluar la descarga sólida de sedimentos de nueve cuencas fluviales de Cataluña: Ter, Foix, Gaia, Besós, Llobregat, Francolí, Tordera, Muga, y Fluvia. “Una tarea lenta y no exenta de dificultades”,según Miquel Canals de la Universidad de Barcelona (UB).
Las cuencas fluviales catalanas tienen “un relieve pronunciado, litologías poco resistentes a la erosión, un notable recubrimiento vegetal, y escasa precipitación”. Camino Liquete, autora principal de la investigación y doctora de la UB, afirma que estas cuencas “pueden tener unas de las descargas de agua y de sedimento más bajas de los ríos que vierten al Mediterráneo”.

Catalonian researchers have studied the nine Catalonian fluvial river basins ending at the Mediterranean, and have analyzed their geomorphological, climatic and hydrologic characteristics, as well as the use of ground and the sediments. The investigation seems to suggest that their sedimentary delivery to sea has diminished in the last decades, due to the urbanization in the fluvial river basins, the water extractions, and the retention of the dams.
Although it is very difficult to quantify the environmental factors and anthropogenic that affect the runoff of sediments from rivers to sea, a team of Catalan scientists has collected data to characterize and to evaluate the solid discharge of sediments of nine fluvial river basins of Catalonia: Ter, Foix, Gaia, Kisses, Llobregat, Francolí, Tordera, Muga, and Fluvia. “A task slow and charged of difficulties”, according to Miquel Canals of the University of Barcelona (UB).
The Catalan fluvial river basins have “a pronounced relief, lithologies with a small resistence to the erosion, a remarkable vegetal covering, and lscarce precipitations”. Camino Liquete, main author of the investigation and doctor of the UB, says that these river basins “can have one of the lower water and sediment runoffs of he rivers that spill to the Mediterranean sea”.

Más información/ More information Plataforma SINC

Resumen de la publicación/Abstract of the research paper
Liquete, Camino; Canals, Miquel; Ludwig, Wolfgang; Arnau, Pedro.
“Sediment discharge of the rivers of Catalonia, NE Spain, and the influence of human impacts” Journal of Hydrology 366(1-4): 76-88.
The environmental and anthropogenic factors controlling sediment delivery to the sea are numerous, intricate and usually difficult to quantify. Mediterranean watersheds are historically amongst the most heavily impacted by human activities in the world. This study analyzes some of these factors for nine river systems from Catalonia, NE Spain, that open into the Northwestern Mediterranean Sea, and discusses the results obtained from sediment yield models and sediment concentration data series.
General models indicate that the natural suspended sediment yield by individual catalan rivers ranged within a fork from 94 to 621 t km2 yr1. Such a sediment yield would be noticeably reduced (moving the fork to 7–148 t km2 yr1) because of lithological factors and direct anthropogenic and, possibly, climatic impacts. Damming, water extraction and urbanization appear as the most important direct anthropogenic impacts in Catalonia. Water discharge and sediment concentration measurements by basin authorities provide much lower sediment yield estimations, from 0.4 to 19.8 t km2 yr1, which is probably due to the lack of measured sediment loads during flood events, as it is the case in many other Mediterranean rivers.
The Catalan watersheds have some of the smallest runoff values amongst Mediterranean rivers. Of the nine river systems studied, water discharge tends to decrease in two and to increase in one. The other six river systems do not show any clear tendency. Related to climatic parameters, temperature raised in all the watersheds between 1961 and 1990, while precipitation did not show significant trends.

Predicen ciclones mediterráneos de forma rápida y barata/ Simple and fast prediction of Mediterranean cyclones

Científicos de la Universidad de Islas Baleares han desarrollado una nueva metodología para mejorar la predicción entre 48 y 24 horas antes de los ciclones que ocurren en el Mar Mediterráneo. Los investigadores han aplicado un cálculo estadístico de sensibilidades de la atmósfera real para predecir los ciclones desde una perspectiva climatológica precisa y de bajo coste.

La región mediterránea es una área de ciclones muy activa que con frecuencia se ve afectada por estos fenómenos atmosféricos severos que producen vientos fuertes y lluvias intensas. Aunque la comunidad científica se esfuerza en mejorar la predicción numérica de los ciclones, los sistemas habituales siguen siendo costosos. Los estudios de sensibilidad son una propuesta de bajo coste y eficiente para determinar las estrategias de observación óptimas.

Con este método, los científicos son capaces de mejorar la predicción de la evolución y el impacto de los ciclones entre 48 y 24 horas antes de su formación completa. La temperatura y la velocidad del viento son factores importantes para la predicción del fenómeno.

Según Garcies y Homar del Grupo de Meteorología de la Universidad de las Islas Baleares (UIB) , "los resultados para ciclones mediterráneos intensos muestran coherencia dinámica, espacial y temporal de los campos de sensibilidad, y pueden competir con resultados análogos obtenidos con técnicas mucho más costosas”,

Scientists of the University of the Balearic Islands have developed a new methodology to improve the prediction between 48 and 24 hours before the apparition of the cyclones that happen in the Mediterranean Sea. The researchers have applied a statistical calculation of sensitivities of the real atmosphere to predict cyclones from a low cost and precise climatologic perspective.

The Mediterranean region is a very active cyclone area frequently affected by these severe atmospherics phenomena, that produce strong winds and intense rains. Although the scientific community strives in improving the numerical prediction of cyclones, the habitual systems continue being expensive. The sensitivity studies are a efficient and low-cost proposal to determine the optimal strategies of observation.

With this method, the scientists will be able to improve the prediction of the evolution and the impact of cyclones between 48 and 24 hours before their complete formation. The temperature and the wind speed are important factors for the prediction of the phenomenon.

According to Garcies and Homar from the Metereology Research Group of the University of Balearic Islands (UIB) , “the results for intense Mediterranean cyclones show dynamic, space and temporal coherence of the sensitivity fields, and are coherent with analogous results found by using much more expensive techniques"

Tomado de/ Taken from Plataforma SINC

Resumen de la publicación/ Abstract of the paper
L. GARCIES and V. HOMAR, Ensemble sensitivities of the real atmosphere: application to Mediterranean intense cyclones, Tellus Series A- Dynamic Meteorology and Oceanography, 61(3) : 394-406 (2009. )
DOI 10.1111/j.1600-0870.2009.00392.x

ABSTRACT
Ensemble sensitivity has been recently proposed as an alternative cheap approach to sensitivity analysis. We adapt it to compute climatological sensitivity estimates of intense Mediterranean cyclones using a climatology based of the ECMWF ERA-40 fields. A catalogue of 1202 events, objectively detected and classified in 25 clusters, is used in this study. Sensitivity fields are derived for each intense Mediterranean cyclone type by correlating the precursor conditions with the mature cyclones depths. Corrections to the raw sensitivity estimates are applied by means of the correlation coefficient. Further, a normalization based on the climatological spatial variability of the variance of the precursor conditions is used to derive the final sensitivity fields. The 24 h sensitivity information derived for each intense Mediterranean cyclone type is easily interpretable both in amplitude and distribution. A synthetic result combining the sensitivity fields for all 25 intense Mediterranean cyclone classes shows that the evolution of these high-impact systems 24 h prior to its maturity stage depends largely on structures located over Western Europe, the Northern African lands and parts of east North Atlantic. These results are in agreement and complement with previous results obtained with the expensive adjoint model, although further work is needed to objectively verify the results.

Un método sencillo para predecir las crecidas del Ebro/Simple method to predict Ebro River level rises

Un equipo de investigadores de la Universidad de Castilla-La Mancha (UCLM) ha desarrollado un nuevo modelo matemático que permite predecir de forma sencilla las crecidas del río Ebro en Zaragoza a partir del flujo de agua que se registra en Castejón (Navarra). En una predicción a 20 horas, el sistema acierta el 97,5% de los casos.
El estudio, que se publicará en abril en la revista Environmental Modelling & Software, aborda el problema de cómo modelizar y predecir los flujos y niveles del Ebro en la capital aragonesa, a partir del análisis de un tramo de 110 km que comienza en la localidad navarra de Castejón.
Los investigadores han desarrollado el sistema predictivo en dos etapas. Primero han utilizado una función matemática“de transferencia” para dimensionar el modelo e identificar de forma aproximada el retardo con el que el flujo del agua en Castejón afecta al nivel de las aguas en Zaragoza.
“Pero la dinámica del río no se comporta de forma lineal”, apunta Pedregal. El profesor señala, por ejemplo, que el agua circula más rápido cuando el caudal es medio o bajo, que las tormentas no afectan por igual a un lecho seco (absorbe más el agua) que a uno húmedo, o que los deshielos rápidos arrastran un aguanieve que se comporta de forma diferente al agua líquida.
Todos estos factores, además de la propia física de los fluidos, hacen que la dinámica de los ríos sea “no lineal”, por lo que los investigadores han aplicado sistemas matemáticos de este tipo y han propuesto un algoritmo específico que recoja la influencia de las variables.
La capacidad predictiva del modelo se ha contrastado con la información de la base de datos histórica de la Confederación Hidrográfica del Ebro, produciendo unos errores medios del 2,5% en un horizonte de predicción de 20 horas.

A team of researchers from the University of Castilla-La Mancha (UCLM) has developed a new mathematical method to easily predict rises in the level of the Ebro River in Zaragoza based on water flow recorded in Castejón (Navarre). The system has a 97.5% success rate for 20-hour predictions.
The study, to be published in April in the journal Environmental Modelling & Software, looks at the problem of how to model and predict the flow and levels of the Ebro in the regional capital of Aragon, based on analysis of a 110km section that starts in the town of Castejón, in Navarre.
The researchers developed the predictive system in two stages. First of all they used a mathematical “transfer” function to determine the scale of the model and get an approximate idea of the time delay before the water flowing through Castejón has an impact on water levels in Zaragoza.
“But the river’s dynamics don’t behave in a linear way,” points out Pedregal: the water flows more quickly when it is at an average or low level, that storms do not have the same effect on a dry river bed (which absorbs more water) as a wet one, and that rapid thawing of snow introduces slushy water into the river, which behaves in a different way than liquid water.
All these factors, along with the physics of fluid itself, means that the dynamics of rivers are “not linear”, resulting in the researchers having had to use mathematical systems to reflect these factors and produce a specific algorithm to incorporate the impact of all these variables.
The predictive ability of the model has been contrasted with information from the historical database of the Hydrographic Confederation of the Ebro River, resulting in an average error rate of 2.5% over a 20-hour prediction timescale.

Tomado de/Taken from Plataforma SINC/Science Daily

Resumen de la publicación/Abstract of the paper
D.J. Pedregal, R. Rivas, V. Feliu, L. Sánchez y A. Linares. A non-linear forecasting system for the Ebro River at Zaragoza, Spain. Environmental Modelling & Software, 2009; 24 (4): 502
Abstract
This paper addresses the problem of modelling and forecasting river flows and levels based on flood routing type models. Though this is generally considered as a non-linear problem, very often it is treated by linear models. A forecasting system is built for the level and flow measurements registered in the Ebro River at the station of Zaragoza (Spain), with the main purpose of preventing floods in an early stage of development. The model takes advantage of the wealth of data available at the Ebro Hydrographical Confederation and is non-linear in essence. The system is obtained by application of system identification tools, starting from a linear specification and relating the parameters of the model estimated to some transformation of the input in the system. Such transformation requires the application of a Kalman Filter in a particular set up and the full estimation algorithm involves an iterative procedure. The model is fully developed on a data set and is thoroughly validated on a different span of data

El cambio climático modificará la aparición de incendios/Climate Change will modify the wildfire occurrence

El cambio climático traerá un cambio en la pauta de los incendios a nivel mundial, y estos cambios llegan rápido, según el primer análisis de este tipo, realizado por investigadores de la Universidad de California en Berkeley en colaboración con científicos de la Universidad Tecnológica de Texas.
Los investigadores usaron datos de sensores infrarrojos y térmicos tomados entre 1996 y 2006 por satélites de la Agencia Espacial Europea para su estudio de pirogeografía: la distribución y comportamiento de los incendios, para determinar las características ambientales comunes asociadas con el riesgo de los mismos. Luego han incorporado estas variables en proyecciones acerca de cómo futuros escenarios climáticos, podrán influir en la aparición de los incendios a nivel mundial.
El estudio ha encontrado que gran parte del planeta sufrirá cambios en la actividad incendiaria, y esto implica tanto el aumento como la disminución de la probabilidad de aparición de incendios. Hay áreas en las que raramente se producían incendios en el pasado, que experimentarán un gran aumento de los mismos en el período 2010-2039. Por el contrario, otras regiones donde los fuegos eran comunes en el pasado, serán consideradas como áreas de riesgo en disminución.
Estos estudios preliminares muestran punbtos calientes de aumento en el oeste de los Estados Unidos y en la meseta tibetana, mientras que regiones tales como el noroeste de China o el África central serán menos proclives a los incendios en las próximas décadas.

Climate change will bring about major shifts in worldwide fire patterns, and those changes are coming fast, according to a first-of-its-kind analysis led by researchers at the University of California, Berkeley, in collaboration with scientists at Texas Tech University.
Researchers used thermal-infrared sensor data obtained between 1996 and 2006 from European Space Agency satellites in their study of pyrogeography – the distribution and behavior of wildfire – on a global scale. They not only got a global view of where wildfires occur, but they determined the common environmental characteristics associated with the risk of those fires. They then incorporated those variables into projections for how future climate scenarios will impact wildfire occurrence worldwide.
The study has found that much of the planet will incur changes in fire activity, and this includes increases as well as decreases in the likelihood of fire. Specific areas where wildfire occurrence was rare in the past are projected to experience large increases in fire activity in the period 2010-2039. Regions where fire was common in the past and projected to experience a large decrease were considered areas at risk of fire retreat.
These preliminary results show hotspots of fire invasion forming in parts of the western United States and the Tibetan plateau, while regions including northeast China and central Africa may become less fire-prone in the coming decades.

Tomado de/Taken from Science Daily; University of Berkeley

Resumen de la publicación científica/Abstract of the research paper
Krawchuk MA, Moritz MA, Parisien M-A, Van Dorn J, Hayhoe K (2009) Global Pyrogeography: the Current and Future Distribution of Wildfire. PLoS ONE 4(4): e5102. doi:10.1371/journal.pone.0005102
Climate change is expected to alter the geographic distribution of wildfire, a complex abiotic process that responds to a variety of spatial and environmental gradients. How future climate change may alter global wildfire activity, however, is still largely unknown. As a first step to quantifying potential change in global wildfire, we present a multivariate quantification of environmental drivers for the observed, current distribution of vegetation fires using statistical models of the relationship between fire activity and resources to burn, climate conditions, human influence, and lightning flash rates at a coarse spatiotemporal resolution (100 km, over one decade). We then demonstrate how these statistical models can be used to project future changes in global fire patterns, highlighting regional hotspots of change in fire probabilities under future climate conditions as simulated by a global climate model. Based on current conditions, our results illustrate how the availability of resources to burn and climate conditions conducive to combustion jointly determine why some parts of the world are fire-prone and others are fire-free. In contrast to any expectation that global warming should necessarily result in more fire, we find that regional increases in fire probabilities may be counter-balanced by decreases at other locations, due to the interplay of temperature and precipitation variables. Despite this net balance, our models predict substantial invasion and retreat of fire across large portions of the globe. These changes could have important effects on terrestrial ecosystems since alteration in fire activity may occur quite rapidly, generating ever more complex environmental challenges for species dispersing and adjusting to new climate conditions. Our findings highlight the potential for widespread impacts of climate change on wildfire, suggesting severely altered fire regimes and the need for more explicit inclusion of fire in research on global vegetation-climate change dynamics and conservation planning.

El Aguila Imperial Ibérica se recupera/Iberian Imperial Eagle is recovering

A pesar de ser una de las especies más vulnerables según la lista roja de la Unión Internacional para la Conservación de la Naturaleza (IUCN, por sus siglas en inglés), el águila imperial (Aquila adalberti) se está recuperando en España. La especie se ha multiplicado por seis, pasando de 38 parejas de águila en 1974 a 253 en 2008, un dato esperanzador para los científicos que han realizado el estudio demográfico en la Península Ibérica.
"El trabajo muestra que la especie se ha recuperado y que tiene una buena capacidad de respuesta a las actuaciones de conservación. Aunque ya se sabía desde hace tiempo, el estudio demuestra, una vez más, que es una especie muy sensible a los cambios en la supervivencia adulta”, explica a SINC Santi Mañosa, uno de los autores del estudio e investigador de la Universidad de Barcelona.
Según datos del Ministerio de Medio Ambiente, Medio Rural y Marino (MARM), en 2008 había 253 parejas de águila imperial. La especie ha aumentado en toda su área de reproducción a excepción del Parque Nacional de Doñana (Huelva) donde la población estuvo afectada gravemente por el uso ilegal de cebos envenenados en especial en los ‘90.
La colaboración entre los diferentes agentes sociales (investigadores, cazadores, agricultores, gestores forestales, industria energética, entre otros), es importante para que exista “un consenso estatal entre todas las Comunidades Autónomas y para regular todas las actividades que pueden afectar a la especie”.



Despite being one of the most threatened species on the International Union for Nature Conservation (IUCN)'s red list, the Spanish imperial eagle (Aquila adalberti) is recovering in Spain. The species has undergone a six-fold increase, from 38 pairs in 1974 to 253 in 2008, data viewed as hopeful by the scientists who carried out the demographic study on the Iberian Peninsula.
"This study shows that the species has recovered and has responded well to conservation initiatives. Although it has been known for a long time, the study shows once again that this species is highly affected by changes in adult survival rates", Santi Mañosa, one of the authors of the study and a researcher at the University of Barcelona, tells SINC.
Data from the Ministry of the Environment and Rural and Marine Affairs (MARM) show that there were 253 pairs of imperial eagles in 2008. The species has experienced an increase throughout its entire area of reproduction, except in the Doñana National Park in Huelva, where the population has been seriously affected by the illegal use of poisoned bait, especially during the 1990s.
Collaboration between various social agents (researchers, hunters, farmers, forest managers, the energy industry, etc.) is important to ensure the existence of "nationwide consensus between all the autonomous regions, and to regulate all those activities that could affect the species".

Tomado de/Taken from Plataforma SINC /Science Daily

Referencia bibliográfica/Journal reference
Ortega, Enric; Mañosa, Santi; Margalida, Antoni; Sánchez, Roberto; Oria, Javier; González, Luis Mariano. A demographic description of the recovery of the Vulnerable Spanish imperial eagle Aquila adalberti. Oryx, 2009; 43 (1): 113 DOI: 10.1017/S0030605307991048

Resumen/Summary
The population of the Vulnerable Spanish imperial eagle Aquila adalberti has experienced a gradual recovery from 38 pairs (1974) to 198 (2004). We analysed the spatial and temporal variation of the demographic parameters for 1981–2004. Annual productivity was 1.19–1.32 chicks per female and adult survival rate 0.918–0.986. Survival during the post-fledging period was 0.894 and the annual survival rate of the dispersing individuals was 0.561. Three phases of population evolution were distinguished: growth (1981–1993), stability or slight decrease (1994–1999) and growth (2000–2004). Variation in adult survival seems to explain this pattern for the first two periods. However, a large disparity between the observed growth rate and the modelled population growth in 2000–2004 is best explained if we assume that a decrease in the age of recruitment took place. This is supported by the recent increase in the frequency of non-adult birds in breeding pairs. The survival of unpaired eagles in dispersal areas is becoming more important for the maintenance of current population growth. Spatial variation of adult survival and breeding success is not congruent with the observed growth rate of the population, which suggests the existence of an important flow of individuals between populations. These results highlight the importance of addressing the conservation of the species from a global perspective and the need to focus on adult survival in breeding territories and on non-adult survival in dispersal areas.

Nacen tres linces en Doñana/Three lynxes are born in Doñana

Tres nuevos cachorros de lince ibérico (Lynx pardinus) han nacido en el centro de El Acebuche en Doñana dentro del programa de cría en cautividad impulsado por la Consejería de Medio Ambiente y el Ministerio de Medio Ambiente, Medio Rural y Marino como apoyo a la conservación de esta especie en peligro de extinción.
Los cachorros, de los que todavía se desconoce su sexo, son hijos de Saliega (nacida en Sierra morena) y Almoradux, un macho de Doñana. Esta camada mixta es especialmente importante debido a que aumenta la variabilidad genética.
Estos son los primeros partos que se producen este año en El Acebuche. Hasta el momento un total de 16 hembras han copulado en los tres centros, si bien existe un alto porcentaje de hembras primerizas cuya gestación podría resultar complicada.
El Programa de Cría en Cautividad tiene como objetivo asegurar a corto plazo la conservación del material genético de la especie y crear, a medio y largo plazo, nuevas poblaciones a través de programas de reintroducción de este felino calificado como en peligro crítico de extinción en el mundo.

Three new cubs of Iberian Lynx (Lynx pardinus) have been born in the Acebuche Center in Doñana (Sapin) within the Program of Breeding in Captivity, promoted by the Andalusian Council of Environment and the Spanish Ministry of Environment, within the support to the conservation of this species in extinction danger.
The cubs, of sex unknown, are children of Saliega (born in Sierra Morena) and Almoradux, a male from Doñana. This mixed litter is especially important because it increases the genetic variability.
These are the first births that take place this year in the Acebuche. Until now, a total of 16 lynx females have copulated, although a high percentage of beginner females exists whose gestation could be complicated.
The objective of the Program of Breeding in Captivity his to ensure, at short term, the genetic storage and maintenance of materiel from the species and create, in the medium and long term, new populations through reintroduction programs from this feline in critical danger of extinction in the world.

Tomado de/Taken from: Ecodiario.es

La sequía Amazónica/The Amazonia drought

Según las últimas investigaciones realizadas en la selva tropical más extensa, el Amazonas ha resultado ser sorprendentemente sensible a la sequía. El estudio publicado en Science, y que ha durado 30 años, proporciona la primera evidencia sólida de que la sequía, al matar los árboles, produce una pérdida masiva de carbono en los bosques tropicales.
De acuerdo al Profesor Oliver Phillips, de la Universidad de Leeds, y autor principal de este trabajo, "durante muchos años, la selva amazónica ha ayudado a retrasar el cambio climático. Pero confiar en este subsidio de la naturaleza, puede ser muy peligroso".
El estudio, una colaboración de más de 40 instituciones, se basó en la inusual sequía amazónica de 2005. Esto dio a los científicos un atisbo del futuro clima de la región, en la que el calentamiento tropical del Atlántico Norte podría originar estaciones secas más calientes e intensas.
La sequía del 2005 invirtió de manera abrupta varias décadas de absorción de carbono, durante las cuales la Amazonía ayudó a retardar el cambio climático. En años normales, la selva absorbe casi 2.000 millones de toneladas de dióxido de carbono. La sequía produjo una pérdida de más de 3.000 millones de toneladas. El impacto total de la sequía, 5.000 millones de toneladas de dióxido de carbono más en la atmósfera, es mayor que las emisiones combinadas de Europa y Japón.


The Amazon is surprisingly sensitive to drought, according to new research conducted throughout the world's largest tropical forest. The 30-year study, published in Science, provides the first solid evidence that drought causes massive carbon loss in tropical forests, mainly through killing trees.
"For years the Amazon forest has been helping to slow down climate change. But relying on this subsidy from nature is extremely dangerous", said Professor Oliver Phillips, from the University of Leeds and the lead author of the research.
The study, a global collaboration between more than 40 institutions, was based on the unusual 2005 drought in the Amazon. This gave scientists a glimpse into the region's future climate, in which a warming tropical North Atlantic may cause hotter and more intense dry seasons.
The 2005 drought sharply reversed decades of carbon absorption, in which Amazonia helped slow climate change. In normal years the forest absorbs nearly 2 billion tonnes of carbon dioxide. The drought caused a loss of more than 3 billion tonnes. The total impact of the drought - 5 billion extra tonnes of carbon dioxide in the atmosphere - exceeds the annual emissions of Europe and Japan combined.

Tomado de/Taken from Science Daily

Los barcos emiten tanta contaminación como la mitad de los coches del mundo/Commercial ships spew half as much particulate pollution as world's cars

Los barcos comerciales emiten casi la mitad de contaminantes sólidos como lo hacen la totalidad de los automóviles del mundo, según afirma un nuevo estudio de la National Oceanic and Atmospheric Administration de los E.E.U.U. y la Universidad de Boulder (Colorado). Los autores estiman que los barcos smiten alredededor de 1,100 toneladas de contaminación al año.
"Como más del 70% del tráfico marítimo sucede dentro de 250 millas de la costa, esto significa un problema de salud para las comunidades costeras", según el director del estido, Daniel Lack del NOAA's Earth System Research Laboratory en Boulder.
Los barcos emiten partículas y dióxido de carbono, que tienen efectos contrarios sobre el clima. Las partículas ejercen un efecto de enfriamiento global cinco veces más potente que el efecto de calentamiento global del dióxido de carbono emitido.
Las partículas también afectan a la salud. Los barcos emiten sulfatos regulados por la Convención para la Prevención de la Polución por los Barcos, pero también contaminantes orgánicos y hollín o sea carbón negro, que contribuyen al 50% de las emisiones, y que no son regulados en la actualidad.

Commercial ships emit almost half as much particulate pollutants into the air globally as the total amount released by the world's cars, according to a new study led by the National Oceanic and Atmospheric Administration and the University of Colorado at Boulder. The authors estimate ships emit about 1,100 tons of particle pollution globally each year.
"Since more than 70 percent of shipping traffic takes place within 250 miles of the coastline, this is a significant health concern for coastal communities" said lead study author Daniel Lack, a researcher with the NOAA-supported CU Cooperative Institute for Research in Environmental Sciences based at NOAA's Earth System Research Laboratory in Boulder.
Commercial ships emit both particle pollution and carbon dioxide, but they have opposite effects on the climate, said the researchers. The particles have a global cooling effect that is at least five times greater than the global warming effect from the ships' CO2 emissions. The particles affect both climate and health.
Ships emit sulfates regulated by the International Convention for the Prevention of Pollution from Ships, but also organic pollutants and sooty, black carbon -- which make up the other half of emissions -- are not directly targeted by today's regulations.

Tomado de Science Daily

El coste escondido de los bio-combustibles/ The hidden cost of biofuels

Los combustibles biológicos podrían perder su tono verde si se producen a expensas de los bosques tropicales.
Los científicos advierten de que la demanda de bio-combustibles líquidos podría originar una enorme tala de árboles, que liberaría más carbono a la atmósfera que el ahorrado por el cambio a combustibles más verdes.
Holly Gibbs, investigadora en la Universidad de Stanford que presentó el 14 de febrero su informe sobre el uso del territorio y la producción de bio-diesel, durante la reunión anual de la Asociación Americana para el Avance de la Ciencia, afirma que “la letra pequeña es que los combustibles biológicos basados en productos agrícolas van a aumentar las emisiones de gases de efecto invernadero si continúan siendo producidos de la manera en que se está haciendo hoy”
La demanda creciente de combustibles basados en productos agrícolas, por ejemplo maíz, aceite de la soja, de mandioca y de palma tiene efectos devastadores. La mayoría de los países industrializados que pretenden substituir los combustibles fósiles por combustibles biológicos, no tienen regiones agrícolas para producirlos. Y además, muchas de las plantas más prometedoras, tales la caña de azúcar y la palma, se adaptan mejor a las zonas tropicales, por lo que es preciso quemar el bosque tropical para despejar el terreno en que deben plantarse.
Gibbs considera que los biocombustibles se ajustan a las ecuaciones energéticas del futuro, pero que "ningún biocombustible va a poder satisfacer todas nuestras necesidades energéticas, por lo que necesitamos una cartera variada". Se necesitan políticas e incentivos para que se usen tierras previamente degradadas, una empresa que es actualmente de alto coste y de bajo beneficio.

Biofuels could lose their green sheen if they are grown at the expense of tropical forests.
Demand for the liquid fuels could lead to severe deforestation, researchers warn, which would release far more carbon into the atmosphere than that saved by switching to the greener fuels.
“The bottom line is that crop-based biofuels are going to increase greenhouse gas emissions if they continue to be produced the way they are today” says Holly Gibbs, a research fellow at Stanford University, who presented a new assessment of land use and biofuel production February 14 at the annual meeting of the American Association for the Advancement of Science.
Increased demand for biofuel crops such as corn, soybean, cassava and palm oil has ripple effects, Gibbs says. Most industrialized countries aiming to replace fossil fuels with biofuels don’t have the agricultural land to grow these fuels. And many of the most promising plants, such as sugarcane and palm oil, are better suited to the tropics anyway. The primary source of new cropland to grow these plants is cleared and burned tropical forest.
Gibbs is certain that biofuels fit into the energy equations of the future. But “no single biofuel is going to be able to fulfill our energy needs. We need a diversified portfolio,” she says. Policy and market incentives are needed to use already degraded land for crops, an endeavor that is currently high cost, low profit.

Tomado de/Taken from Science News

Cambio climático irreversible/Climate change is irreversible

Un nuevo estudio científico liderado por la estadounidense NOAA (National Oceanic and Atmospheric Administration) ha alcanzado una conclusión de gran alcance, sobre el cambio climático originado por futuros aumentos del dióxido de carbono: en gran parte, no hayvuelta atrás.
El estudio demuestra como los cambios en la temperatura de la superficie terrestre, lluvias y nivel del mar son en gran parte irreversibles, por más de 1.000 años después de que las emisiones de CO2 se hayan detenido por completo. Los hallazgos aparecerán surante la semana del 26 de enero en los Proceedings of the National Academy of Sciences.

A new scientific study led by the National Oceanic and Atmospheric Administration reaches a powerful conclusion about the climate change caused by future increases of carbon dioxide: to a large extent, there’s no going back.
The study shows how changes in surface temperature, rainfall, and sea level are largely irreversible for more than 1,000 years after carbon dioxide (CO2) emissions are completely stopped. The findings appear during the week of January 26 in the Proceedings of the National Academy of Sciences.

Tomado de/Taken from NOAA/Science Daily

LA NIÑA DE 12 AÑOS QUE SILENCIÓ AL MUNDO (CUMBRE DE RÍO DE JANEIRO SOBRE LA TIERRA , 1992) / ENVIROMENTAL RÍO JANEIRO 1992 ONU

Traemos este grito terriblemente razonado de la niña que es y representa, la generación de nuestros hijos, a la cual, como ella dijo:

estamos aniquilando


¿qué autoridad moral podemos tener desde la acción hipócrita del día a día?

Ocurrió en la CUMBRE DE RÍO DE JANEIRO SOBRE MEDIO AMBIENTE CELEBRADA EL 3 AL 14 DE JUNIO DE 1992, POR NACIONES UNIDAS Y DESARROLLO (ONU)