34 research outputs found
Editorial: Root functional traits: From fine root to community-level variation
Artículo incluido en la sección Functional Plant Ecology[ES] Plant roots perform multiple essential functions defining plant ecological success and
ecosystem functioning. For instance, roots are vital for plant nutrient and water uptake,
thus regulating net primary production and nutrient cycling (Freschet et al., 2021). In the
last decade, the adoption and advancement of a functional trait approach has greatly
improved our understanding of root ecology, evidenced by the recent increase of global
syntheses on root trait research (e.g., Freschet et al., 2018; Bergmann et al., 2020; Carmona
et al., 2021; Freschet et al., 2021). However, there are still gaps and controversy in our
understanding of root trait–functioning relationships (Freschet et al., 2021). Roots display a
wide diversity of morphologies and symbiotic associations (i.e., with mycorrhizal fungi and
rhizobium), which has made it challenging to seek general patterns across the diverse taxa
that inhabit different ecological conditions worldwide (Ma et al., 2018). In this special issue,
we bring together studies on root ecology that tackle important unresolved questions and
emerging topics, which collectively highlight new knowledge and critical knowledge gaps in
belowground ecologySIMarı́a Zambrano contract funded by the Spanish Ministry of UniversitiesSpanish Ministry of UniversitiesMinistry of Science and InnovationEuropean Union-Next Generation PlanEuropean Union FEDER fun
Functional Plant Types Drive Plant Interactions in a Mediterranean Mountain Range
This article was submitted to Functional Plant Ecology section[EN] Shrubs have positive (facilitation) and negative (competition) effects on understory plants, the net interaction effect being modulated by abiotic conditions. Overall shrubs influence to great extent the structure of plant communities where they have significant presence. Interactions in a plant community are quite diverse but little is known about their variability and effects at community level. Here we checked the effects of co-occurring shrub species from different functional types on a focal understory species, determining mechanisms driving interaction outcome, and tested whether effects measured on the focal species were a proxy for effects measured at the community level. Growth, physiological, and reproductive traits of Euphorbia nicaeensis, our focal species, were recorded on individuals growing in association with four dominant shrub species and in adjacent open areas. We also recorded community composition and environmental conditions in each microhabitat. Shrubs provided environmental conditions for plant growth, which contrasted with open areas, including moister soil, greater N content, higher air temperatures, and lower radiation. Shrub-associated individuals showed lower reproductive effort and greater allocation to growth, while most physiological traits remained unaffected. Euphorbia individuals were bigger and had more leaf N under N-fixing than under non-fixing species. Soil moisture was also higher under N-fixing shrubs; therefore soil conditions in the understory may counter reduced light conditions. There was a significant effect of species identity and functional types in the outcome of plant interactions with consistent effects at individual and community levels. The contrasting allocation strategies to reproduction and growth in Euphorbia plants, either associated or not with shrubs, showed high phenotypic plasticity and evidence its ability to cope with contrasting environmental conditionsSIWe thank Cristina Armas, Christian Schöb, Francisco Padilla, and Manuela Guler for help in the field and laboratory, and the Organismo Autónomo Parques Nacionales (grant 0002/9) and MINECO (CGL2014-51090-R) for financial support. Cristina Armas provided valuable comments on earlier versions of this manuscript and two anonymous reviewers provided valuable comments to improve the manuscript. PM was supported by JAE-Doc Program (CSIC) co-financed by ESF, and later by MSMT LM2015078. IP was supported by a CSIC contract (project RNM 4821) and then by an Agence Nationale de la Recherche project (Ecosfix ANR-10-STRA-003-001). JM was supported by Postdok_BIOGLOBE (CZ.1.07/2.3.00/30.0032) co-financed by ESF and CR budge
Linking functional composition moments of the sub-Mediterranean ecotone with environmental drivers
This article is part of the Research Topic Plant Diversity: The Key to Ecosystem Resilience in a Changing World[EN] Introduction: Functional trait-based approaches are extensively applied to the study of mechanisms governing community assembly along environmental gradients. These approaches have been classically based on studying differences in mean values among species, but there is increasing recognition that alternative metrics of trait distributions should be considered to decipher the mechanisms determining community assembly and species coexistence. Under this framework, the main aim of this study is to unravel the effects of environmental conditions as drivers of plant community assembly in sub- Mediterranean ecotones. Methods: We set 60 plots in six plant communities of a sub-Mediterranean forest in Central Spain, and measured key above- and belowground functional traits in 411 individuals belonging to 19 species, along with abiotic variables. We calculated community-weighted mean (CWM), skewness (CWS) and kurtosis (CWK) of three plant dimensions, and used maximum likelihood techniques to analyze how variation in these functional community traits was driven by abiotic factors. Additionally, we estimated the relative contribution of intraspecific trait variability and species turnover to variation in CWM. Results and discussion: The first three axes of variation of the principal component analyses were related to three main plant ecological dimensions: Leaf Economics Spectrum, Root Economics Spectrum and plant hydraulic architecture, respectively. Type of community was the most important factor determining differences in the functional structure among communities, as compared to the role of abiotic variables. We found strong differences among communities in their CWMs in line with their biogeographic origin (Eurosiberian vs Mediterranean), while differences in CWS and CWK indicate different trends in the functional structure among communities and the coexistence of different functional strategies, respectively. Moreover, changes in functional composition were primarily due to intraspecific variability.
Conclusion: We observed a high number of strategies in the forest with the different communities spreading along the acquisitive-conservative axis of resource-use, partly matching their Eurosiberian-Mediterranean nature, respectively. Intraspecific trait variability, rather than species turnover, stood as
the most relevant factor when analyzing functional changes and assembly patterns among communities. Altogether, our data support the notion that ecotones are ecosystems where relatively minor environmental shifts may result in changes in plant and functional compositionSIThis work was financially supported by the German Research Foundation (Deutsche Forschungsgemeinschaft), being part of the project “the Functional Frontier among Mediterranean and Eurosiberian Plant Communities” (ECOFUMER, 441909701). ER and JG are respectively supported by a Marı́a Zambrano and a Margarita Salas fellowships funded by the Spanish Ministry of Universities and European Union-Next Generation Plan. IP acknowledges funding from a Ramón y Cajal contract (RYC2021-033081-I) funded by the Ministry of Science and Innovation and co-funded by the European Union-Next Generation Plan funded by European Union-NextGenerationE
Pushing the limits of C3 intrinsic water use efficiency in Mediterranean semiarid steppes: responses of a drought‐avoider perennial grass to climate aridification
[EN] 1. Intrinsic water use efficiency (WUEi) reflects the trade-off between photo- synthetic carbon gain and water loss through stomatal conductance and is key for understanding dryland plant responses to climate change. Stipa tenacissima is a perennial tussock C3 grass with an opportunistic, drought- avoiding water use strategy that dominates arid and semiarid steppes across the western Mediterranean region. However, its ecophysiological responses to aridification and woody shrub encroachment, a major land-use change in drylands worldwide, are not well-understood. 2. We investigated the variations in leaf stable isotopes (δ18 O, δ13 C, δ15 N), nutrient concentrations (N, P, K), and culm water content and isotopic composition (δ18 O,δ2H) of paired pure-grass and shrub-encroached S. tenacissima steppes along a 350 km aridity gradient in Spain (10 sites, 160 individuals). 3. Culm water isotopes revealed that S. tenacissima is a shallow-rooted grass that depends heavily on recent rainwater for water uptake, which may render it vulnerable to increasingly irregular rainfall combined with faster topsoil drying under climate warming and aridification. With increasing aridity, S. tenacissima enhanced leaf-level WUEi through more stringent stomatal regulation of plant water flux and carbon assimilation (higher δ13C and δ18 O), reaching exceptionally high δ13C values (−23‰ to −21‰) at the most arid steppes. Foliar N concentration was remarkably low across sites regardless of woody shrub encroachment, evidencing severe water and N co-limitation of photosynthesis and productivity. Shrub encroachment decreased leaf P and K but did not affect S. tenacissima water status. Perennial grass cover decreased markedly with both declining winter rainfall and shrub encroachment suggesting population-level rather than individual-level responses of S. tenacissima to these changes.4. The fundamental physiological constraints of photosynthetic C3 metabolism com-bined with low foliar N content may hamper the ability of S. tenacissima and other drought-avoider species with shallow roots to achieve further adaptive improve-ments in WUEi under increasing climatic stress. A drought-avoiding water use strategy based on early stomatal closure and photosynthesis suppression during prolonged rainless periods may thus compromise the capacity of semiarid S. tena-cissima steppes to maintain perennial grass cover, sustain productivity and cope with ongoing climate aridification at the drier parts of their current distributionSISpanish Ministry of Science and Innovation, Grant/Award Number: EUR2022-134048, PRX19/00301, PID2019-107382RB-I00, CGL2013- 48753-R, CGL2010-21064, AGL- 2006-11234, PID2020-113021RA-I00, RTI2018- 098895-A-100 and RYC- 2016-20604; Fundación BBVA, Grant/ Award Number: BIOCON06/105; Universidad Rey Juan Carlos, Grant/Award Number: URJC-RNT- 063-2; European Research Council, Grant/Award Number: 647038; Generalitat Valenciana, Grant/ Award Number: CIDEGENT/2018/041; National Natural Science Foundation of China, Grant/Award Number: 41801091; China Postdoctoral Science Foundation, Grant/Award Number: 2018M643542 and 2019T120868; Fundación Séneca, Grant/ Award Number: 20654/JLI/
Mulching treatments favour the recovery of ecosystem multifunctionality after a large wildfire in Northwest Spain
[EN] Wildfires are a widespread phenomenon in forests across the Mediterranean Basin but have increased in risk and severity
in recent decades. Post-fire treatments are measures that help recover burned vegetation and their functionality but to
what extent they also help recover soil functionality is currently unknown. The main objective of this study was to assess
the effect of post-fire treatments on ecosystem multifunctionality after a large wildfire in the Cabrera mountain range in
2017 (NW Spain) where close to 10000 Ha of forest were burnt. At the end of 2017 and during 2018, the administration
applied different post-fire treatments in high fire severity affected areas: i) straw mulching, ii) woody debris and iii)
subsoiling and iv) mechanical hole afforestation. In each treatment, we established ten 2 x 2 m plots and ten adjacent
untreated burned plots and collected a composite soil sample from each plot four years after the fire (2021). We
calculated regulating services as the standardized mean of total soil organic C (climate regulation), soil water repellence
(water regulation) and soil aggregation (soil protection). Supporting services were measured as the standardized mean
of mineral N-NH4+ and N-NO3- and available P (soil fertility), β-glucosidase, urease and acid phosphatase (nutrient
cycling) and microbial biomass (soil quality). Ecosystem multifunctionality was measured as the standardized mean of
all functions measured. Application of straw mulch and woody debris increased regulating ecosystem services in relation
to burned control plots. Afforestation with holes had no impact but subsoiling decreased regulating ecosystem services
in relation to burned control plots. Post-fire treatments did not have any effect on supporting services. Straw mulch,
Woody debris and afforestation with holes improved ecosystem multifunctionality when compared with subsoiling
methods. These results show that post-fire stabilisation treatments, in particular straw mulching have a significant
positive impact on regulating services and are effective measures in restoring the ecosystem multifunctionality, helping
develop effective management based-decisions for the recovery of ecosystem services and functioning after large
wildfiresThis research was financially supported by the Spanish Ministry of Economy and Competitiveness in the framework of the FIRESEVES (AGL2017-86075-C2-1-R) project, and by the Regional Government of Castilla and León in the framework of the WUIFIRECYL (LE005P20) projec
Coexistencia en ecosistemas sub-Mediterráneos y cambio climático
[ES] En la Península Ibérica se dan cambios graduales entre la vegetación Mediterránea y Eurosiberiana, encontrando áreas de ecotono donde conviven comunidades vegetales de ambas regiones, conocidas como zonas Sub-Mediterráneas. En general, estas zonas de ecotono se caracterizan por albergar una gran diversidad y representan áreas prioritarias desde el punto de vista de la conservación. Las predicciones del IPCC indican que el clima en la cuenca Mediterránea se volverá más cálido y seco, lo que implicará cambios sustanciales en la composición de especies de los ecosistemas forestales de estas zonas límite. Por lo tanto, se considera que son ecosistemas altamente vulnerables al cambio climático y un área de investigación prioritaria. En este artículo, abordamos cómo la ecología funcional, que focaliza sus estudios en los rasgos o características de la hoja, tallo y raíz, puede ayudar a explicar la coexistencia entre especies eurosiberianas, como el haya, y especies mediterráneas, como el roble melojo, en estos ecotonos o ecosistemas de transición. El Grupo de Ecología Aplicada y Teledetección (GEAT) de la Universidad de León desarrolla parte de su investigación en identificar y predecir cómo el cambio climático puede afectar a las comunidades vegetales de estos ecotonos
Aprendizaje-Servicio en el entorno rural de León
[ES] A través del grupo de Innovación Docente BIOMETAC, nace esta experiencia de ApS para promover en los
estudiantes de los grados en Biología, Biotecnología y Ciencias Ambientales de la ULE, la iniciativa cívica de
participación en la sociedad. El objetivo general del proyecto es que el alumnado aplique sus conocimientos y
habilidades para sensibilizar y dinamizar a la población de varios municipios rurales de León frente a retos de la
Agenda 2030 asociados a la salud y la sostenibilidad ambiental. Se establecieron 3 grupos de trabajo, cada uno
integrado por 12 estudiantes de los tres grados, que trabajan en 3 municipios rurales de la provincia de León:
Cistierna, Truchas y Villablino, con diversas problemáticas en el ámbito de la salud y medioambiente. El Proyecto
se realiza en tres fases: Preparación, Ejecución y Evaluación y Difusión. Durante la primera fase (curso 2021/22),
se realizaron reuniones con el alumnado para guiarlos en el diagnóstico de cada municipio. Los datos obtenidos
permitieron detectar los problemas que más preocupaban a la población de cada municipio. En una segunda fase
(curso 2022/23), los alumnos profundizarán en las distintas problemáticas mediante actuaciones propuestas por
ellos mismos y presentarán sus conclusiones en cada municipio. Esta experiencia pretende que los estudiantes
pongan los conocimientos y las competencias adquiridas al servicio de comunidades rurales, trabajando
directamente sobre varios Objetivos de Desarrollo Sostenible (ODS), mejorando su capacidad de iniciativa,
autonomía en la organización del trabajo, y responsabilidad para la resolución de problemas
Management of acute diverticulitis with pericolic free gas (ADIFAS). an international multicenter observational study
Background: There are no specific recommendations regarding the optimal management of this group of patients. The World Society of Emergency Surgery suggested a nonoperative strategy with antibiotic therapy, but this was a weak recommendation. This study aims to identify the optimal management of patients with acute diverticulitis (AD) presenting with pericolic free air with or without pericolic fluid. Methods: A multicenter, prospective, international study of patients diagnosed with AD and pericolic-free air with or without pericolic free fluid at a computed tomography (CT) scan between May 2020 and June 2021 was included. Patients were excluded if they had intra-abdominal distant free air, an abscess, generalized peritonitis, or less than a 1-year follow-up. The primary outcome was the rate of failure of nonoperative management within the index admission. Secondary outcomes included the rate of failure of nonoperative management within the first year and risk factors for failure. Results: A total of 810 patients were recruited across 69 European and South American centers; 744 patients (92%) were treated nonoperatively, and 66 (8%) underwent immediate surgery. Baseline characteristics were similar between groups. Hinchey II-IV on diagnostic imaging was the only independent risk factor for surgical intervention during index admission (odds ratios: 12.5, 95% CI: 2.4-64, P =0.003). Among patients treated nonoperatively, at index admission, 697 (94%) patients were discharged without any complications, 35 (4.7%) required emergency surgery, and 12 (1.6%) percutaneous drainage. Free pericolic fluid on CT scan was associated with a higher risk of failure of nonoperative management (odds ratios: 4.9, 95% CI: 1.2-19.9, P =0.023), with 88% of success compared to 96% without free fluid ( P <0.001). The rate of treatment failure with nonoperative management during the first year of follow-up was 16.5%. Conclusion: Patients with AD presenting with pericolic free gas can be successfully managed nonoperatively in the vast majority of cases. Patients with both free pericolic gas and free pericolic fluid on a CT scan are at a higher risk of failing nonoperative management and require closer observation
Report: Labour and social security law in Spain in 2013
El informe ha sido elaborado por la Sección Juvenil de la Asociación Española de Derecho del Trabajo y Seguridad SocialEste documento intenta reflejar algunos de los principales cambios y novedades del ordenamiento laboral español en 2013, levantando acta de cómo la mutabilidad de nuestro Derecho del Trabajo es imparable. Este informe, consciente de ello, ofrece una selección de elementos esenciales, a juicio de sus autores, especialistas en cada una de las materias, encuadrados en la Sección Juvenil de la Asociación Española de Derecho del Trabajo y de la Seguridad Social. En él, conforme a la organización de dicha Sección en grupos de trabajo, se abordan las novedades más relevantes en materia de derechos fundamentales inespecíficos, contratación laboral, vicisitudes del contrato de trabajo, Derecho colectivo, conciliación y corresponsabilidad, protección social y prevención de riesgos laborales.This paper tries to show some of the many changes and novelties in Spanish Labour Law during 2013, drawing up a record of the unstoppable character of our Labour legal system. This report offers a selection of essential elements, according to its authors, all of them specialists in each one of the subjects, being part of the Young Scholars’ Section of the Spanish Association for Labour and Social Security Law. According to the organization of the said Section in working groups, we can find novelties concerning unspecific fundamental rights, work contracts, the life of the work contract and collective Labour Law, reconciliation and co responsibility, social protection and occupational risk preventio
Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)
Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters.
Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs).
Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001).
Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio