Reforestación con arbustos para favorecer la conectividad ecológica en el Corredor Verde del Guadiamar

Se propone un diseño de restauración ecológica cuya función específica es fomentar la conectividad regional de un agrosistema (que ha sido contaminado con lodos mineros y posteriormente remediado) para múltiples especies de fauna forestal a través del Paisaje Protegido del Corredor Verde del Guadiamar, Sevilla. La propuesta se basa en el principio de aumentar la heterogeneidad espacial de la vegetación a varias escalas, tanto desde el punto de vista estructural como de diversidad de especies, para tratar de facilitar el aumento de especies animales que de ella dependen y la conectividad del conjunto. Para ello se ha diseñado un sistema de plantación de leñosas arbustivas en forma de parches discretos, distribuidos espacialmente en los herbazales regenerados espontáneamente en la zona inundable del río tras el episodio de contaminación y posterior recuperación de los suelos. Se plantean tres cuestiones para contrastar la capacidad real del modelo de reforestación para satisfacer los objetivos de conservación: 1) Comprobar si el diseño y ejecución de la plantación son adecuados para producir una vegetación estructurada, diversa y que ofrezca un hábitat de calidad para las especies de fauna forestal. 2) Comprobar si el aumento de la diversidad florística (en especies leñosas) se refleja en un aumento de la diversidad de especies animales. 3) Comprobar si el cambio en la cantidad y disposición espacial de la vegetación leñosa favorece la conectividad para las especies de fauna forestal. En este trabajo se presentan algunos resultados preliminares obtenidos a varias escalas: a) En una parcela piloto de 15 ha donde se han plantado 14.668 plantas de 16 especies autóctonas sobre la que se ha realizado un seguimiento de su supervivencia y crecimiento durante los tres primeros años. b) Estudios extensivos en zonas de diferente cobertura arbustiva (plantaciones de hace 7-9 años) a lo largo del Corredor Verde del Guadiamar y en fragmentos forestales vecinos. c) Resultados preliminares sobre el uso que están haciendo de estos parches algunas especies de mamíferos, así como de los movimientos de una especie de mariposa entre fragmentos

Reforestación con arbustos para favorecer la conectividad ecológica en el Corredor Verde del Guadiamar

Se propone un diseño de restauración ecológica cuya función específica es fomentar la conectividad regional de un agrosistema (que ha sido contaminado con lodos mineros y posteriormente remediado) para múltiples especies de fauna forestal a través del Paisaje Protegido del Corredor Verde del Guadiamar, Sevilla. La propuesta se basa en el principio de aumentar la heterogeneidad espacial de la vegetación a varias escalas, tanto desde el punto de vista estructural como de diversidad de especies, para tratar de facilitar el aumento de especies animales que de ella dependen y la conectividad del conjunto. Para ello se ha diseñado un sistema de plantación de leñosas arbustivas en forma de parches discretos, distribuidos espacialmente en los herbazales regenerados espontáneamente en la zona inundable del río tras el episodio de contaminación y posterior recuperación de los suelos. Se plantean tres cuestiones para contrastar la capacidad real del modelo de reforestación para satisfacer los objetivos de conservación: 1) Comprobar si el diseño y ejecución de la plantación son adecuados para producir una vegetación estructurada, diversa y que ofrezca un hábitat de calidad para las especies de fauna forestal. 2) Comprobar si el aumento de la diversidad florística (en especies leñosas) se refleja en un aumento de la diversidad de especies animales. 3) Comprobar si el cambio en la cantidad y disposición espacial de la vegetación leñosa favorece la conectividad para las especies de fauna forestal. En este trabajo se presentan algunos resultados preliminares obtenidos a varias escalas: a) En una parcela piloto de 15 ha donde se han plantado 14.668 plantas de 16 especies autóctonas sobre la que se ha realizado un seguimiento de su supervivencia y crecimiento durante los tres primeros años. b) Estudios extensivos en zonas de diferente cobertura arbustiva (plantaciones de hace 7-9 años) a lo largo del Corredor Verde del Guadiamar y en fragmentos forestales vecinos. c) Resultados preliminares sobre el uso que están haciendo de estos parches algunas especies de mamíferos, así como de los movimientos de una especie de mariposa entre fragmentos

Ectomycorrhizal fungal communities and their functional traits mediate plant–soil interactions in trace element contaminated soils

There is an increasing consensus that microbial communities have an important role in mediating ecosystem processes. Trait-based ecology predicts that the impact of the microbial communities on ecosystem functions will be mediated by the expression of their traits at community level. The link between the response of microbial community traits to environmental conditions and its effect on plant functioning is a gap in most current microbial ecology studies. In this study, we analyzed functional traits of ectomycorrhizal fungal species in order to understand the importance of their community assembly for the soil–plant relationships in holm oak trees (Quercus ilex subsp. ballota) growing in a gradient of exposure to anthropogenic trace element (TE) contamination after a metalliferous tailings spill. Particularly, we addressed how the ectomycorrhizal composition and morphological traits at community level mediate plant response to TE contamination and its capacity for phytoremediation. Ectomycorrhizal fungal taxonomy and functional diversity explained a high proportion of variance of tree functional traits, both in roots and leaves. Trees where ectomycorrhizal fungal communities were dominated by the abundant taxa Hebeloma cavipes and Thelephora terrestris showed a conservative root economics spectrum, while trees colonized by rare taxa presented a resource acquisition strategy. Conservative roots presented ectomycorrhizal functional traits characterized by high rhizomorphs formation and low melanization which may be driven by resource limitation. Soil-to-root transfer of TEs was explained substantially by the ectomycorrhizal fungal species composition, with the highest transfer found in trees whose roots were colonized by Hebeloma cavipes. Leaf phosphorus was related to ectomycorrhizal species composition, specifically higher leaf phosphorus was related to the root colonization by Thelephora terrestris. These findings support that ectomycorrhizal fungal community composition and their functional traits mediate plant performance in metal-contaminated soils, and have a high influence on plant capacity for phytoremediation of contaminants. The study also corroborates the overall effects of ectomycorrhizal fungi on ecosystem functioning through their mediation over the plant economics spectrum

Functional diversity of ectomycorrhizal fungal communities is reduced by trace element contamination

10 páginas.-- 2 figuras.-- 3 tablas.-- 105 referencias.-- Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.soilbio.2018.03.021Trait-based approaches are useful tools to explain ecological assembly rules and ecosystem functioning. However, their use for soil microbiota has not been explored in depth yet. We explored trait-based functional changes of ectomycorrhizal (ECM) fungal communities associated with holm oak (Quercus ilex subsp. ballota) in a trace element contaminated area. We found a variation in ECM fungal species composition determined by soil C, Ca and trace elements; however, taxonomic diversity was not dependant on contamination level. Mean trait values of ECM fungal communities showed less rhizomorph and emanating hyphae production when increasing contamination, and the community converged towards species developing rhizomorphs less frequently. We suggest that trace elements in soils acted as the main environmental filter of trait diversity of ECM fungal communities. The effect of soil nutrients, i.e. soil C, affected the community mean trait values of emanating hyphae but did not cause a convergence in its distribution. In summary, we found a reduction in the functional diversity of ECM fungal communities due to trace element contamination with potential to affect ecosystem functioning. This finding supports the potential of trait-based approaches to assess changes in the functional diversity of soil microbial communities.This work was supported by European Union Seventh Framework Programme (FP7/2007–2013) [grant number 603498 - RECARE]; Spanish Ministry of Economy and Competitiveness [grant number CGL2014-52858-R - RESTECO]; Spanish National Research Programme - European Union (Feder) [grant number CGL2015-69118-C2-2-P - COEXMED-II]. During manuscript preparation, ALG was supported by European Union's Horizon 2020 Marie Curie Individual Fellowship [grant number 708530 - DISPMIC]. MTD is thankful the University of Sevilla for a postdoctoral fellowship (V Plan Propio de Investigación).Peer reviewe

Distributions of phytoplankton carbohydrate, protein and lipid in the world oceans from satellite ocean colour

Energy value of phytoplankton regulates the growth of higher trophic species, affecting the tropic balance and sustainability of marine food webs. Therefore, developing our capability to estimate and monitor, on a global scale, the concentrations of macromolecules that determine phytoplankton energy value, would be invaluable. Reported here are the first estimates of carbohydrate, protein, lipid, and overall energy value of phytoplankton in the world oceans, using ocean-colour data from satellites. The estimates are based on a novel bio-optical method that utilises satellite-derived bio-optical fingerprints of living phytoplankton combined with allometric relationships between phytoplankton cells and cellular macromolecular contents. The annually-averaged phytoplankton energy value, per cubic meter of sub-surface ocean, varied from less than 0.1 kJ in subtropical gyres, to 0.5–1.0 kJ in parts of the equatorial, northern and southern latitudes, and rising to more than 10 kJ in certain coastal and optically complex waters. The annually-averaged global stocks of carbohydrate, protein and lipid were 0.044, 0.17 and 0.108 gigatonnes, respectively, with monthly stocks highest in September and lowest in June, over 1997-2013. The fractional contributions of phytoplankton size classes e.g., picoplankton, nanoplankton and microplankton to surface concentrations and global stocks of macromolecules varied considerably across marine biomes classified as Longhurst provinces. Among these provinces, the highest annually-averaged surface concentrations of carbohydrate, protein, and lipid were in North-East Atlantic Coastal Shelves, whereas, the lowest concentration of carbohydrate or lipid were in North Atlantic Tropical Gyral, and that of protein was in North Pacific Subtropical Gyre West. The regional accuracy of the estimates and their sensitivity to satellite inputs are quantified from the bio-optical model, which show promise for possible operational monitoring of phytoplankton energy value from satellite ocean colour. Adequate in situ measurements of macromolecules and improved retrievals of inherent optical properties from high-resolution satellite images, would be required to validate these estimates at local sites, and to further improve their accuracy in the world oceans

Tectonic denudation and topographic development in the Spanish Sierra Nevada

The denudation history of the rapidly uplifting western part of the Spanish Sierra Nevada was assessed using apatite fission track (AFT) ages and 10Be analyses of bedrock and fluvial sediments. Major contrasts in the denudation history are recorded within the 27 km2 Río Torrente catchment. Upland areas are characterized by low-relief, low slope angles, and locally the preservation of shallow marine sediments, which have experienced <200 m of erosion in the last 9 Myr. However, AFT age determinations from samples collected close to the marine sediments imply >2 km of denudation since circa 4 Ma. The minimum denudation rates of 0.4 mm yr−1 derived from AFT also contrast with the slow medium-term (104 years) erosion rates (0.044 ± 0.015 mm yr−1) estimated from 10Be measurements at high elevations. The local medium-long-term contrasts in denudation rates within the high Sierra Nevada indicate that much of the unroofing occurs by tectonic denudation on flat-lying detachments. In lower elevation parts of the catchment, rapid river incision coupled to rock uplift has produced ∼1.6 km of relief, implying that the rivers and adjacent hillslopes close to the edge of the orogen are sensitive to normal-fault-driven changes in base level. However, these changes are not transmitted into the low-relief slowly eroding upland areas. Thus the core of the mountain range continues to increase in elevation until the limits of crustal strength are reached and denudation is initiated along planes of structural weakness. We propose that this form of tectonic denudation provides an effective limit to relief in young orogens

Sex differences in the structure and function of rat middle cerebral arteries

Wang S, Zhang H, Liu Y, Li L, Guo Y, Jiao F, Fang X, Jefferson JR, Li M, Gao W, Gonzalez-Fernandez E, Maranon RO, Pabbidi MR, Liu R, Alexander BT, Roman RJ, Fan F. Sex differences in the structure and function of rat middle cerebral arteries. Am J Physiol Heart Circ Physiol 318: H1219 –H1232, 2020. First published March 27, 2020; doi:10.1152/ajpheart.00722.2019.—Epidemiological studies demonstrate that there are sex differences in the incidence, prevalence, and outcomes of cerebrovascular disease (CVD). The present study compared the structure and composition of the middle cerebral artery (MCA), neurovascular coupling, and cerebrovascular function and cognition in young Sprague-Dawley (SD) rats. Wall thickness and the inner diameter of the MCA were smaller in females than males. Female MCA exhibited less vascular smooth muscle cells (VSMCs), diminished contractile capability, and more collagen in the media, and a thicker internal elastic lamina with fewer fenestrae compared with males. Female MCA had elevated myogenic tone, lower distensibility, and higher wall stress. The stress/strain curves shifted to the left in female vessels compared with males. The MCA of females failed to constrict compared with a decrease of 15.5 ± 1.9% in males when perfusion pressure was increased from 40 to 180 mmHg. Cerebral blood flow (CBF) rose by 57.4 ± 4.4 and 30.1 ± 3.1% in females and males, respectively, when perfusion pressure increased from 100 to 180 mmHg. The removal of endothelia did not alter the myogenic response in both sexes. Functional hyperemia responses to whisker-barrel stimulation and cognition examined with an eight-arm water maze were similar in both sexes. These results demonstrate that there are intrinsic structural differences in the MCA between sexes, which are associated with diminished myogenic response and CBF autoregulation in females. The structural differences do not alter neurovascular coupling and cognition at a young age; however, they might play a role in the development of CVD after menopause. NEW & NOTEWORTHY Using perfusion fixation of the middle cerebral artery (MCA) in calcium-free solution at physiological pressure and systematically randomly sampling the sections prepared from the same M2 segments of MCA, we found that there are structural differences that are associated with altered cerebral blood flow (CBF) autoregulation but not neurovascular coupling and cognition in young, healthy Sprague-Dawley (SD) rats. Understanding the intrinsic differences in cerebrovascular structure and function in males and females is essential to develop new pharmaceutical treatments for cerebrovascular disease (CVD).Fil: Wang, Shaoxun. University Of Mississippi Medical Center; Estados UnidosFil: Zhang, Huawei. University Of Mississippi Medical Center; Estados UnidosFil: Liu, Yedan. University Of Mississippi Medical Center; Estados UnidosFil: Li, Longyang. University Of Mississippi Medical Center; Estados UnidosFil: Guo, Ya. University Of Mississippi Medical Center; Estados UnidosFil: Jiao, Feng. Peking University People's Hospital; China. University Of Mississippi Medical Center; Estados UnidosFil: Fang, Xing. University Of Mississippi Medical Center; Estados UnidosFil: Jefferson, Joshua R.. University Of Mississippi Medical Center; Estados UnidosFil: Li, Man. University Of Mississippi Medical Center; Estados UnidosFil: Gao, Wenjun. University Of Mississippi Medical Center; Estados UnidosFil: Gonzalez Fernandez, Ezekiel. University Of Mississippi Medical Center; Estados UnidosFil: Marañón, Rodrigo Oscar. University Of Mississippi Medical Center; Estados Unidos. Universidad Nacional de Tucumán. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Pabbidi, Mallikarjuna R.. University Of Mississippi Medical Center; Estados UnidosFil: Liu, Ruen. Peking University People's Hospital; ChinaFil: Alexander, Barbara T.. University Of Mississippi Medical Center; Estados UnidosFil: Roman, Richard J.. University Of Mississippi Medical Center; Estados UnidosFil: Fan, Fan. University Of Mississippi Medical Center; Estados Unido

Validation of lipid-related therapeutic targets for coronary heart disease prevention using human genetics

Drug target Mendelian randomization (MR) studies use DNA sequence variants in or near a gene encoding a drug target, that alter the target's expression or function, as a tool to anticipate the effect of drug action on the same target. Here we apply MR to prioritize drug targets for their causal relevance for coronary heart disease (CHD). The targets are further prioritized using independent replication, co-localization, protein expression profiles and data from the British National Formulary and clinicaltrials.gov. Out of the 341 drug targets identified through their association with blood lipids (HDL-C, LDL-C and triglycerides), we robustly prioritize 30 targets that might elicit beneficial effects in the prevention or treatment of CHD, including NPC1L1 and PCSK9, the targets of drugs used in CHD prevention. We discuss how this approach can be generalized to other targets, disease biomarkers and endpoints to help prioritize and validate targets during the drug development process

Primary Production, an Index of Climate Change in the Ocean: Satellite-Based Estimates over Two Decades

Primary production by marine phytoplankton is one of the largest fluxes of carbon on our planet. In the past few decades, considerable progress has been made in estimating global primary production at high spatial and temporal scales by combining in situ measurements of primary production with remote-sensing observations of phytoplankton biomass. One of the major challengesinthisapproachliesintheassignmentoftheappropriatemodelparametersthatdefinethe photosynthetic response of phytoplankton to the light field. In the present study, a global database of in situ measurements of photosynthesis versus irradiance (P-I) parameters and a 20-year record of climatequalitysatelliteobservationswereusedtoassessglobalprimaryproductionanditsvariability with seasons and locations as well as between years. In addition, the sensitivity of the computed primaryproductiontopotentialchangesinthephotosyntheticresponseofphytoplanktoncellsunder changing environmental conditions was investigated. Global annual primary production varied from 38.8 to 42.1 Gt C yr−1 over the period of 1998–2018. Inter-annual changes in global primary production did not follow a linear trend, and regional differences in the magnitude and direction of change in primary production were observed. Trends in primary production followed directly from changes in chlorophyll-a and were related to changes in the physico-chemical conditions of the water column due to inter-annual and multidecadal climate oscillations. Moreover, the sensitivity analysis in which P-I parameters were adjusted by±1 standard deviation showed the importance of accurately assigning photosynthetic parameters in global and regional calculations of primary production. TheassimilationnumberoftheP-Icurveshowedstrongrelationshipswithenvironmental variables such as temperature and had a practically one-to-one relationship with the magnitude of change in primary production. In the future, such empirical relationships could potentially be used for a more dynamic assignment of photosynthetic rates in the estimation of global primary production. RelationshipsbetweentheinitialslopeoftheP-Icurveandenvironmentalvariableswere more elusive