Search

Este trabajo se sitúa en el ámbito del mantenimiento basado en la condición, en el que se realizó la adquisición de señales acústicas y de vibración para el diagnóstico de fallos en un compresor reciprocante de doble etapa, simulando fallos en elementos críticos como; válvulas de admisión y descarga, anillos de pistón y rodamientos de cigüeñal. This work is located in ambit of condition-based maintenance, in which the acquisition of acoustic and vibration signals for fault diagnosis in a double-stage reciprocating compressor was carried out, simulating faults in critical elements such as; intake and discharge valves, piston rings and crankshaft bearings.

133-152 1a edición. 2017 jcalle@ups.edu.ec fmoncayom@est.ups.edu.ec dreinosoz@est.ups.edu.ec ctorresd@est.ups.edu.ec

Los hongos marinos por su condición heterótrofa, su adaptabilidad a la variabilidad ambiental y su resistencia específica a diferentes estresores, son una opción para ser empleados como restauradores de sectores contaminados con antibióticos. Con esta hipótesis se realizó la investigación en una zona de cultivo de salmones en el sur de Chile. Para ello se evaluó la concentración de oxitetraciclina (OTC) de sedimentos de diferentes zonas cercanas a jaulas de cultivo de salmón. También se aisló de sedimentos cepas de hongos para evaluar su capacidad de degradar OTC. Los resultados obtenidos mostraron en el área de estudio concentraciones de OTC que fluctuaron entre 4,62 ± 0,12 a 24,1 ± 1,03 µg g-1, en el sector Este a la balsa jaula y en los sedimentos de 100 m de profundidad. Además, de estos sedimentos se aisló 38 cepas de hongos y se identificó y trabajó con 6 cepas del Phylum Ascomycetes: Penicillium commune, Aspergillus terreus, Beauveria bassiana, Trichoderma harzianum, Epicoccum nigrum y Emericellopsis alkalina. Las pruebas de biodegradación demostraron que las cepas fueron capaces de degradar OTC en porcentajes que fluctuaron entre 76 y 92%. Los resultados representan un primer paso en la implementación de procesos que permitan la biorremediación de residuos de OTC desde los sedimentos. It is proposed that marine fungi are a good alternative for remediation of areas contaminated with antibiotics due to their heterotrophic condition, adaptability to environmental changes, and specific resistance to stressors. With this assumption we investigated the fjords of Southern Chile, which are characterized by salmon farming. We evaluated the concentration of oxytetracycline (OTC) in sediments from different areas surrounding salmon cages. In addition, we isolated fungi species to assess their ability to degrade OTC. Measurable amounts of OTC were detected in deeper sediments located at the eastern sector of cages and rafts (Z= 100 m; 4.62 ± 0.12 to 24.1 ± 1.03 µg g-1). Thirty-eight strains of endemic fungi were isolated and identified in the sediments near the farming center. Among these strains we detected species from the Phylum Ascomycetes, including Penicillium commune, Aspergillus terreus, Beauveria bassiana, Trichoderma harzianum, Epicoccum nigrum and Emericellopsis alkaline. These strains fungi were capable of degrading about 76 to 92% of the OTC present in the culture media. The results of this study constitute a first step into implementing processes that could favor waste bioremediation from marine sediments.

[Aims]: Climate and human impacts are changing the nitrogen (N) inputs and losses in terrestrial ecosystems. However, it is largely unknown how these two major drivers of global change will simultaneously influence the N cycle in drylands, the largest terrestrial biome on the planet. We conducted a global observational study to evaluate how aridity and human impacts, together with biotic and abiotic factors, affect key soil variables of the N cycle., [Location]: Two hundred and twenty-four dryland sites from all continents except Antarctica widely differing in their environmental conditions and human influence., [Methods]: Using a standardized field survey, we measured aridity, human impacts (i.e. proxies of land uses and air pollution), key biophysical variables (i.e. soil pH and texture and total plant cover) and six important variables related to N cycling in soils: total N, organic N, ammonium, nitrate, dissolved organic:inorganic N and N mineralization rates. We used structural equation modelling to assess the direct and indirect effects of aridity, human impacts and key biophysical variables on the N cycle., [Results]: Human impacts increased the concentration of total N, while aridity reduced it. The effects of aridity and human impacts on the N cycle were spatially disconnected, which may favour scarcity of N in the most arid areas and promote its accumulation in the least arid areas., [Main conclusions]: We found that increasing aridity and anthropogenic pressure are spatially disconnected in drylands. This implies that while places with low aridity and high human impact accumulate N, most arid sites with the lowest human impacts lose N. Our analyses also provide evidence that both increasing aridity and human impacts may enhance the relative dominance of inorganic N in dryland soils, having a negative impact on key functions and services provided by these ecosystems., This research is supported by the European Research Council (ERC) under the European Community's Seventh Framework Programme (FP7/2007‐2013)/ERC grant agreement no. 242658 (BIOCOM), and by the Ministry of Science and Innovation of the Spanish Government, grant no. CGL2010‐21381. CYTED funded networking activities (EPES, Acción 407AC0323). S.G. was funded by CONICYT/FONDAP/15110009.

La restauración ecológica es la actividad deliberada que acelera la recuperación de un sistema degradado por acción directa o indirecta de la intervención humana. Las zonas xerofíticas están entre los ecosistemas más degradados donde la baja disponibilidad hídrica hace que los planes de reintroducción sean poco exitosos y extremadamente costosos. La aplicación de hongos endófitos a raíces ha sido reportada como una exitosa estrategia para mantener o mejorar el desempeño ecofisiológico y supervivencia en diferentes especies de arbustos y árboles. En ambientes climáticamente extremos, los endófitos han mostrado proporcionar beneficios en términos de supervivencia y crecimiento a la vegetación que se asocia a ellos. En el presente trabajo mostramos como la inoculación con endófitos aislados desde plantas creciendo en la Antártica mejoran la supervivencia y eficiencia en el uso del agua para el riego en especies nativas de las formaciones xerofíticas: Flourensia thurifera, Senna cumingii y Puya berteroniana. En general, los resultados muestran que la presencia de endófitos mejoró la supervivencia de las tres especies nativas. Por otro lado, la presencia de endófitos mejoró la eficiencia en el uso del agua para el riego, permitiendo alcanzar altos porcentajes de supervivencia en plantas con una reducción en el agua requerida. Los resultados preliminares obtenidos en este estudio sugieren que la aplicación de endófitos antárticos podría ser considerada como una estrategia exitosa para proyectos futuros y programas de reintroducción en zonas áridas y semi-áridas de Chile. Ecological restoration is the deliberate action that speeds recovery from a degraded system by direct or indirect human intervention. Xerophytic formations are among the most degraded ecosystems where low water availability makes reintroduction plans unsuccessful and extremely expensive. Roots inoculation with endophytic fungi has been reported as a successful strategy to maintain or improve the ecophysiological performance and survival in different species of shrubs and trees. In harsh environments, endophytes have been shown to provide benefits in terms of survival and growth for their associated vegetation. In this study, we showed that inoculation with endophytes isolated from plants growing in Antarctica improve survival and water use efficiency for irrigation on native species of xerophytic formations: Flourensia thurifera, Senna cumingii and Puya berteroniana. Overall, the presence of endophytes improved survival of all native species. Furthermore, the presence of endophytes improved water use efficiency for irrigation, reaching higher percentages of survival in plants with a reduction in the added water. The application of Antarctic endophytes could be considered a successful strategy for future projects and reintroduction programs in arid and semi-arid zones of Chile.

The climbing habit is a key innovation in angiosperm evolution: climbing plant taxa have greater species richness than their non-climbing sister groups. It is considered that highly diversified clades should show increased among-population genetic differentiation. Less clear is the expected pattern regarding within-population genetic diversity in speciose lineages. We tested the hypothesis of greater within-population genetic diversity in climbing plants compared to trees in a temperate forest in central Chile. The assumption underlying this hypothesis is that higher among-population differentiation in climbers compared to trees should reflect higher genetic diversity as well. AFLP markers from 167 individual plants from 14 species (seven climbers and seven trees) were used to estimate the following indices of within-population genetic diversity: mean unbiased expected heterozygosity (He), percentage of polymorphic loci (PPL), Shannon information index (I), and the effective number of alleles (Ne). Overall, within-population genetic diversity did not differ between climbing plants and trees. The He for climbing plants was slightly higher than that of trees (0.247 vs. 0.231), and PPL was higher in trees (93.6) than in climbers (81.8), but these differences were not statistically significant. Both I and Ne were very similar for both groups. The expected greater genetic diversity in climbers might have been counterbalanced by tree-related ecological factors that turned to be relevant in the species assemblages studied. Results of this preliminary study should be further confirmed with a broader approach including several forest sites and larger sample sizes. El hábito trepador es una innovación clave en la evolución de las angiospermas: los taxa de plantas trepadoras poseen mayor riqueza de especies que sus grupos hermanos no-trepadores. Se considera que clados altamente diversificados debieran mostrar mayor diferenciación genética entre poblaciones. Menos claro es el patrón esperado respecto a la diversidad genética al interior de las poblaciones en linajes especiosos. Evaluamos la hipótesis de mayor diversidad genética intra-poblacional en plantas trepadoras en comparación con árboles en un bosque templado en Chile central. El supuesto detrás de esta hipótesis es que la mayor diferenciación poblacional en las trepadoras, comparadas con los árboles, debiera reflejar una mayor diversidad genética también. Marcadores AFLP de 167 plantas individuales de 14 especies (siete trepadoras y siete árboles) fueron usados para estimar los siguientes índices de diversidad genética intra-poblacional: heterocigosidad esperada media (He), porcentaje de loci polimórficos (PPL), índice de información de Shannon (I), y el número efectivo de alelos (Ne). En general, la diversidad genética intra-poblacional no difirió entre plantas trepadoras y árboles. La He para plantas trepadoras fue levemente mayor a la de los árboles (0,247 vs. 0,231), y el PPL fue más alto en árboles (93,6) que en trepadoras (81,8), pero estas diferencias no fueron estadísticamente significativas. Tanto I como Ne fueron muy similares en ambos grupos. La mayor diversidad genética esperada en trepadoras puede hacer sido contrarrestada por factores ecológicos particulares a los árboles que resultaron ser relevantes en los ensambles de especies estudiados. Los resultados de este estudio preliminar debieran ser confirmados con una aproximación a mayor escala, incluyendo varios sitios en el bosque y mayores tamaños muestrales.

La Antártica se caracteriza por presentar condiciones ambientales extremas, lo cual limita el establecimiento de las plantas vasculares. Dentro de dichas características ambientales están las bajas temperaturas, corta estación de crecimiento y el estrés hídrico y nutricional. La baja disponibilidad hídrica ha sido sugerida como la principal limitante para el éxito de establecimiento, debido a que afecta de manera negativa las respuestas fisiológicas y reproductivas de las plantas. Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae) es una de las dos plantas vasculares nativas que habitan la Antártica Marítima y se ha demostrado que su desempeño fisiológico y reclutamiento es afectado negativamente por el estrés hídrico del suelo. La plasticidad fenotípica y la adaptación local serían dos de las principales estrategias de C. quitensis para lidiar con las adversas condiciones ambientales que predominan en el continente antártico. Se ha documentado que, bajo un escenario futuro de cambio climático, la disponibilidad hídrica en la Antártica aumentaría entre un 30-40%, mejorando las condiciones para el establecimiento. En el presente trabajo evaluamos mediante un experimento de jardín común, realizado en cámaras de crecimiento, la plasticidad morfo-fisiológica y el esfuerzo reproductivo en individuos de C. quitensis provenientes de dos sitios en las Islas Shetland, bajo un escenario simulado de cambio climático (aumento en un 40% de la disponibilidad hídrica) y bajo la situación actual (disponibilidad hídrica registrada en los sitios de origen). En general, los individuos de C. quitensis de ambos sitios presentaron evidencia de plasticidad, aumentando su eficiencia fotoquímica, largo y ancho foliar, y esfuerzo reproductivo bajo la condición de aumento en la disponibilidad hídrica. La magnitud del aumento en la respuesta plástica fue mayor en aquellos individuos provenientes del sitio más árido en comparación a sus con-específicos del sitio más húmedo. Si los actuales patrones de cambio climático se mantienen, las condiciones abióticas podrían volverse más favorables para C. quitensis, mejorando su desempeño ecofisiológico y permitiendo la expansión de su rango de distribución sobre la Antártica. Antarctica is characterized by extreme environmental conditions, which limit the establishment of vascular plants. These environmental conditions include low temperatures, short growing season and shortage of water and nutrients. Low water availability has been suggested as the main constraint to successful establishment, because it adversely affects the reproductive and physiological responses of plants. Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae) is one of the two native vascular plants that inhabit the Maritime Antarctic and its physiological performance and recruitment have been shown to be negatively affected by soil water stress in the Antarctica. Phenotypic plasticity and local adaptation would be two of the main strategies of C. quitensis to cope with adverse environmental conditions prevailing in the Antarctic continent. It has been suggested that, under a future climate change scenario, water availability will increase by 30-40%, improving the conditions for plant establishment. In this study we evaluated in a common garden experiment, conducted in growth chambers, the morpho-physiological plasticity and reproductive effort in C. quitensis individuals from two sites located in the Shetland Islands, under a simulated scenario of climate change (40% increase in water availability) and under the current situation (water availability recorded in the sites of origin). overall, individuals of C. quitensis of both sites showed a plastic response, increasing the photochemical efficiency, leaf width and length and reproductive effort under increased water availability. Plasticity was greater in those individuals from the more arid site as compared to con-specifics from a mesic site. If current climate change patterns are maintained, abiotic conditions could become more favorable for C. quitensis, improving ecophysiological performance and allowing the spread of its range in the Antarctic.

Se evaluó el efecto de la temperatura y el humo sobre la germinación de Helenium aromaticum; una planta anual abundante en matorrales incendiados. Encontramos que las semillas son resistentes a la alta temperatura (100°C) y al humo, pero su germinación no es estimulada por estos factores. Otras señales del fuego deben ser evaluadas.

The karyotype of Chaetanthera renifolia (J. Remy) Cabrera from Chile was examined. The species has 2n = 2x = 44 chromosomes, with lm+ lst + 2st-sat+ 17t+ lt-satchromosomes. The reported karyotype is bimodal and very asymmetric (AsK % = 86.6, TF % = 13.4 and Syi % = 15.5). These results are indicating that this species has the highest known chromosome number of the genus so far and the most asymmetrical karyotype of the group.

Several studies have revealed a variety of mechanisms of invasion of alien plant species. However, little is known on how those mechanisms and their associated effects on native species change across different life-cycle stages. Under controlled conditions, we assessed the interactions between the alien invasive species Centaurea solstitialis L. (Asteraceae) and two pioneer native species to the Chilean matorral; Baccharis linearis (Ruiz et Pav.) Pers. and B. paniculata DC. (Asteraceae). Competitive effects of the invader on natives were evaluated by combining different life-cycle stages: seed-seed, plant-seed, and plant-plant. Seed germination of C. solstitialis was explosive and much faster than that of the native species. The presence of C. solstitialis (individuals or seeds) did not affect negatively the seed germination of the two Baccharis species. However, the presence of C. solstitialis plants significantly decreased the total biomass oí Baccharis plants. Thus, the effect of C. solstitialis on Baccharis species depended on the life-cycle stage at which the interactions occurred. In the Chilean matorral, the early emergence of C. solstitialis could be an important invasion mechanism, enabling established plants to competitively displace late emerging seedlings of Baccharis species. The huge abundance of C. solstitialis in some disturbed matorrals suggests that seedling establishment of these two pioneer species could be limited. Varios estudios han revelado una variedad de mecanismos de invasión en las plantas alóctonas. Sin embargo, aún se conoce poco sobre cómo tales mecanismos y sus efectos asociados cambian a través de diferentes estados del ciclo vida. En este estudio evaluamos, bajo condiciones controladas, el resultado de las interacciones competitivas entre la especie invasora Centaurea solstitialis L. (Asteraceae) y dos especies pioneras nativas del matorral chileno; Baccharis linearis (Ruiz et Pav.) Pers. y B. paniculata DC (Asteraceae). Estas interacciones fueron evaluadas combinando diferentes estados del ciclo de vida: semilla-semilla, planta-semilla y planta-planta. La germinación de C. solstitialis fue explosiva, siendo mucho más rápida que la de las especies nativas. La presencia de C. solstitialis (plantas o semillas) no disminuyó la germinación de las especies nativas de Baccharis. Sin embargo, la presencia de plantas establecidas de C. solstitialis disminuyó significativamente la biomasa de las plantas de Baccharis. Entonces, el efecto de C. solstitialis sobre las especies de Baccharis varió en función del estado del ciclo de vida en el cual las interacciones ocurrieron. En el matorral chileno, la emergencia temprana y explosiva de C. solstitialis podría ser un importante mecanismo de invasión, ya que aquellas plantas prontamente establecidas podrían desplazar competitivamente a las plántulas de Baccharis que emergen más tarde. La enorme abundancia de C. solstitialis en algunas zonas de matorral sugiere que el establecimiento de plántulas de estas dos especies pioneras podría estar siendo limitado.

La actividad de polinizadores puede ser afectada por factores bióticos (e.g., densidad floral en el parche, despliegue floral) o por factores abióticos (e.g., temperatura, velocidad de viento, nubosidad). A pesar de la notable variación local, estacional e interanual en temperatura en zonas alpinas, las consecuencias de la variación microclimática local sobre la actividad de los polinizadores han recibido escasa atención en ambientes de alta montaña. En este estudio comparamos las tasas de visita a flores de polinizadores realizadas sobre poblaciones de exposición norte y oeste, en Chaetanthera apiculata (3.100 m de altitud), y en poblaciones de exposición este y oeste en C. lycopodioides (3.300 m de altitud). Se estudiaron los sistemas de reproducción de ambas especies para determinar su nivel de dependencia de un agente de polinización externo. En C. apiculata, la población que crece sobre la ladera de exposición norte estuvo sujeta a mayores temperaturas diurnas (1,8 °C) y mayores tasas de visita (7,8 veces) que la población sobre la ladera de exposición oeste. En C. lycopodioides, a su vez, la ladera de exposición este fue más cálida (3 °C) y más visitada (cuatro veces) que la población de exposición oeste. Mientras en C. apiculata, solo Faunula leucoglene (Lepidóptera: Satyridae) presentó mayor actividad en la población más cálida, en C. lycopodioides, solo F. leucoglene y Liphantus sp. (Himenóptera: Andrenidae) tuvieron mayor actividad en la población más cálida. La tasa de visitas de Faunula leucoglene fue afectada por la temperatura en C. apiculata y C. lycopodioides. Ambas especies, C. apiculata y C. lycopodioides, son parcialmente autocompatibles, y por lo tanto requieren polen exógeno para alcanzar una producción de semillas máxima. Nuestros resultados muestran que en ambientes de alta montaña las tasas de visita de polinizadores son altamente variables y que los factores microclimáticos pueden generar más variación en las tasas de visitas a flores que la densidad de capítulos florales en los parches. Nuestros resultados aportan valiosa información sobre las potenciales consecuencias del cambio climático global en la polinización Insect pollinator activity can be influenced by biotic (e.g., patch floral density and floral display) or by abiotic factors (e.g., temperature, wind velocity, cloudiness). In spite of microsite, seasonal and interannual variation in temperature in the alpine zone, the consequences of local microclimatic variation on pollinator activity has been rarely studied in high mountain ecosystems. In this study we compared flower visitation rates on a north-facing slope and a west-facing slope in Chaetanthera apiculata (3,100 m of altitude) and on an east-facing slope and a west-facing slope in Chaetanthera lycopodioides (3,300 m of altitude). We studied the breeding system in each species in order to determine level of dependence on external pollinators. While the north-facing slope inhabited by C. apiculata was warmer (1.8 °C) and visited (7.8-fold) more frequently than the west-facing slope, in C. lycopodioides the east-facing slope was warmer (3 °C) and visited more frequently (4-fold) than the west-facing slope. In C. apiculata only Faunula leucoglene (Lepidóptera: Satyridae) showed higher activity in the warmer population. In C. lycopodioides, F. leucoglene and Liphantus sp. (Himenóptera:Andrenidae) showed higher activity rates in the warmer population. Flower visitation rate in Faunula leucoglene was correlated with temperature in C. apiculata and C. lycopodioides. Both C. apiculata and C. lycopodioides are partially self-compatible, and thus require exogenous pollen for maximum seed set. Our results show that in high elevation environments flower visitation rates can be highly variable and that microclimatic conditions can be more important for pollinator variation among populations than head density. Our results offer valuable insights on the potential consequences of global warming on plant pollination at high elevation

Aims Climate and human impacts are changing the nitrogen (N) inputs and losses in terrestrial ecosystems. However, it is largely unknown how these two major drivers of global change will simultaneously influence the N cycle in drylands, the largest terrestrial biome on the planet. We conducted a global observational study to evaluate how aridity and human impacts, together with biotic and abiotic factors, affect key soil variables of the N cycle. Location Two hundred and twenty-four dryland sites from all continents except Antarctica widely differing in their environmental conditions and human influence. Methods Using a standardized field survey, we measured aridity, human impacts (i.e. proxies of land uses and air pollution), key biophysical variables (i.e. soil pH and texture and total plant cover) and six important variables related to N cycling in soils: total N, organic N, ammonium, nitrate, dissolved organic:inorganic N and N mineralization rates. We used structural equation modelling to assess the direct and indirect effects of aridity, human impacts and key biophysical variables on the N cycle. Results Human impacts increased the concentration of total N, while aridity reduced it. The effects of aridity and human impacts on the N cycle were spatially disconnected, which may favour scarcity of N in the most arid areas and promote its accumulation in the least arid areas. Main conclusions We found that increasing aridity and anthropogenic pressure are spatially disconnected in drylands. This implies that while places with low aridity and high human impact accumulate N, most arid sites with the lowest human impacts lose N. Our analyses also provide evidence that both increasing aridity and human impacts may enhance the relative dominance of inorganic N in dryland soils, having a negative impact on key functions and services provided by these ecosystems.

9 páginas.- 5 figuras.- 51 referencias.- Supplementary information The online version contains supplementary material available at https://doi.org/10.1038/s41561-023-01170-x, Soil mosses are among the most widely distributed organisms on land. Experiments and observations suggest that they contribute to terrestrial soil biodiversity and function, yet their ecological contribution to soil has never been assessed globally under natural conditions. Here we conducted the most comprehensive global standardized field study to quantify how soil mosses influence 8 ecosystem services associated with 24 soil biodiversity and functional attributes across wide environmental gradients from all continents. We found that soil mosses are associated with greater carbon sequestration, pool sizes for key nutrients and organic matter decomposition rates but a lower proportion of soil-borne plant pathogens than unvegetated soils. Mosses are especially important for supporting multiple ecosystem services where vascular-plant cover is low. Globally, soil mosses potentially support 6.43 Gt more carbon in the soil layer than do bare soils. The amount of soil carbon associated with mosses is up to six times the annual global carbon emissions from any altered land use globally. The largest positive contribution of mosses to soils occurs under a high cover of mat and turf mosses, in less-productive ecosystems and on sandy and salty soils. Our results highlight the contribution of mosses to soil life and functions and the need to conserve these important organisms to support healthy soils., The study work associated with this paper was funded by a Large Research Grant from the British Ecological Society (no. LRB17\1019; MUSGONET). D.J.E. is supported by the Hermon Slade Foundation. M.D.-B. was supported by a Ramón y Cajal grant from the Spanish Ministry of Science and Innovation (RYC2018-025483-I), a project from the Spanish Ministry of Science and Innovation for the I + D + i (PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033a) and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). E.G. is supported by the European Research Council grant agreement 647038 (BIODESERT). M.B. is supported by a Ramón y Cajal grant from Spanish Ministry of Science (RYC2021-031797-I). A.d.l.R is supported by the AEI project PID2019-105469RB-C22. L.W. and Jianyong Wang are supported by the Program for Introducing Talents to Universities (B16011) and the Ministry of Education Innovation Team Development Plan (2013-373). The contributions of T.G. and T.U.N. were supported by the Research Program in Forest Biology, Ecology and Technology (P4-0107) and the research projects J4-3098 and J4-4547 of the Slovenian Research Agency. The contribution of P.B.R. was supported by the NSF Biological Integration Institutes grant DBI-2021898. J. Durán and A. Rodríguez acknowledge support from the FCT (2020.03670.CEECIND and SFRH/BDP/108913/2015, respectively), as well as from the MCTES, FSE, UE and the CFE (UIDB/04004/2021) research unit financed by FCT/MCTES through national funds (PIDDAC).

12 páginas.- 3 figuras.- 56 referencias.- Supplementary information The online version contains supplementary material available at https://doi.org/10.1038/s41467-023-37428-6, Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing., This study was supported by a 2019 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation (URBANFUN), and by the BES grant agreement No LRB17\1019 (MUSGONET). We are grateful for the assistance of Yunyun Hao and Xuemei Han during soil sampling. We also thank Drs. Shuai Du and Xiuli Hao for their help in data analyses. M. D-B. is supported by the projects from the Spanish Ministry of Science and Innovation (PID2020-115813RA-I00) (SOIL4GROWTH) and TED2021-130908B-C41 (URBANCHANGE) funded by MCIN/AEI/10.13039/501100011033, and a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático “01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación”) associated with the research project P20_00879 (ANDABIOMA). Y-R. L. is supported by the National Natural Science Foundation of China (42177022). M.G.A.H is supported by the Swiss National Science Foundation (310030_188799). D.J.E. is supported by the Hermon Slade Foundation. F.B. and J.L.M. acknowledge support from the Spanish Ministry and FEDER funds for the project AGL2017-85755-R, the I+D+i project PID2020-114942RB-I00 funded by MCIN/AEI/10.13039/ 501100011033, the i-LINK+2018 (LINKA20069) from CSIC, as well as funds from “Fundación Séneca” from Murcia Province (19896/GERM/15). E.M.-J. was supported by an Experienced Researcher Fellowship of the Humboldt Foundation. E.M-J. and C.P. acknowledge support from the Spanish Ministry of Science and Innovation (PID2020-116578RB-I00). F.A. is supported by ANID FONDECYT 1220358. H-W.H. and J-Z.H. are supported by the project (DP210100332) from Australian Research Council. S.A. is funded by ANID FONDECYT 1170995 and ANID ANILLO ACT192027. MB is supported by a Ramón y Cajal grant from Spanish Ministry of Science (RYC2021-031797-I). The contribution of TG and TUN was supported by the Research Program in Forest Biology, Ecology and Technology (P4-0107) and project V4-3098 of the Slovenian Research Agency. T.P.M. would like to acknowledge contributions from the National Research Foundation of South Africa and cities involved in the South African survey. J.D. and A. Rey acknowledge support from the FCT (IF/00950/2014 and SFRH/BDP/108913/2015, respectively). JPV is thankful to SERB (EEQ/2021/001083) and DST (DST/INT/SL/P-31/2021) and BHU-IoE (6031)-incentive grant for research and development. MCR acknowledges support from an ERC Advanced Grant (694368). AM acknowledged financial support from the PMRF, Ministry of Education - Government of India, India.

14 páginas.- 7 figuras.- 49 referencias, Background Little is known about the global distribution and environmental drivers of key microbial functional traits such as antibiotic resistance genes (ARGs). Soils are one of Earth’s largest reservoirs of ARGs, which are integral for soil microbial competition, and have potential implications for plant and human health. Yet, their diversity and global patterns remain poorly described. Here, we analyzed 285 ARGs in soils from 1012 sites across all continents and created the first global atlas with the distributions of topsoil ARGs. Results We show that ARGs peaked in high latitude cold and boreal forests. Climatic seasonality and mobile genetic elements, associated with the transmission of antibiotic resistance, were also key drivers of their global distribution. Dominant ARGs were mainly related to multidrug resistance genes and efflux pump machineries. We further pinpointed the global hotspots of the diversity and proportions of soil ARGs. Conclusions Together, our work provides the foundation for a better understanding of the ecology and global distribution of the environmental soil antibiotic resistome., This project received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement 702057 (CLIMIFUN), a Large Research Grant from the British Ecological Society (agreement no. LRA17\1193; MUSGONET), and from the European Research Council (ERC grant agreement no. 647038, BIODESERT). M. D. B. was also supported by a Ramón y Cajal grant (RYC2018-025483-I). M.D-B. also acknowledges support from the Spanish Ministry of Science and Innovation for the I+D+i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. M.D-B. is also supported by a project of the Fondo Europeo de Desarrollo Regional (FEDER) and the Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático “01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación”) associated with the research project P20_00879 (ANDABIOMA). FTM acknowledges support from Generalitat Valenciana (CIDEGENT/2018/041). J. Z. H and H. W. H. are financially supported by Australian Research Council (DP210100332). We also thank the project CTM2015-64728-C2-2-R from the Ministry of Science of Spain. C. A. G. and N. E. acknowledge funding by the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, funded by the German Research Foundation (FZT 118). TG was financially supported by Slovenian Research Agency (P4-0107, J4-3098 and J4-4547)