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The UN 2030 Agenda for Sustainable Development Goal 15, termed Life on Land, is monitored by indicators and sub-indicators that largely deal with forest extent. In countries with structurally complex and species-rich forests, indicators and sub-indicators of forest quality are also needed to effectively monitor and sustain ecological integrity. The goal of the paper is to demonstrate the use of complementary sub-indicators of forest quality for SDG15 reporting and conservation planning. Our objective is to apply these sub-indicators within Colombia, Ecuador, and Peru and evaluate spatial patterns and trends over time as a basis for revealing how the results complement the official indicators of forest extent and forest extent in protected areas in informing conservation. The sub-indicators of forest quality quantify naturalness, riparian forest, forest structure and integrity, forest fragmentation, and forest connectivity. We quantified change during 2000–2021 in these metrics and highlighted insights gained from the complementary sub-indicators of forest quality relative to the official sub-indicators based on forest extent,Forests covered about 60–70% of the forested ecoregions in each country in 2000 and this proportion declined in all three countries by approximately 4% by 2021. Only a subset of the forested area was of high forest quality. Natural forests represented about 40% of forests in Colombian and Ecuador in 2000 and 50% in Peru. Those proportions declined: by 6.3% in Colombia, 6.5% in Ecuador, and 3.4% in Peru. Even less of the forested area was Core Forest in 2013; less than 28% among countries. During 2013–2021, the proportion of forest that was Core decreased by 2.3% in Colombia, 4.5% in Ecuador, and 6.7% in Peru. Connected Forests were about 17–22% of forests among the countries in 2013 and declined 10.4% in Colombia, 1.6% in Ecuador, and 3.8% in Peru by 2021. Forests high in forest structure were 10–18% of forests in 2012 among the countries and increased by 1.1–2% by 2021. Forests of high integrity were 7–13% of forests in 2012 and increased by1.4–2% by 2021. Riparian forests represented less than about 7–9% among the countries and declined by 0.6–1.3% by 2021. Thus, the area of highly quality forest across the countries was substantially less than full forest extent and high-quality forest declined at a higher rate than forest extent during 2000–2021. Forest structure and integrity did increase slightly over this time period.Our results for trends in forest naturalness, riparian association, within stand structure, fragmentation, and connectivity demonstrate how consideration of forest quality provides a much stronger basis for evaluating success in meeting SDG15 targets than consideration of forest extent alone.

Introduction: Monitoring the partial pressure of CO2 (PCO2) in newborns who require ventilation would allow avoiding hypocapnia and hypercapnia. The measurement of end-tidal carbon dioxide (ETCO2) is an alternative rarely implemented in this population. Objective: To evaluate the relationship between ETCO2 and PCO2 in newborns. Methods: Cross-sectional study comparing two PCO2 measurement methods, the conventional one by analysis of blood samples and the one estimated by ETCO2. The study included hospitalized newborns that required conventional mechanical ventilation. The ETCO2 was measured with a Tecme GraphNet® neo, a neonatal ventilator with an integrated capnograph, and we obtained the ETCO2–PCO2 gradient. We conducted correlation and Bland-Altman plot analyses to estimate the agreement. Results: A total of 277 samples (ETCO2 / PCO2) from 83 newborns were analyzed. The mean values ​​of ETCO2 and PCO2 were 41.36 mmHg and 42.04 mmHg. There was a positive and significant correlation between ETCO2 and PCO2 in the overall analysis (r = 0.5402; P ETCO2) in 2 of the units, and a negative difference in the third (PCO2 < ETCO2). Discussion: The correlation between ETCO and PCO2 was significant, although the obtained values ​​were not equivalent, with differences ranging from 0.1 mmHg and 20 mmHg. Likewise, we found systematic errors that differed in sign (positive or negative) between institutions. Resumen: Introducción: Monitorear la presión parcial de CO2 (PCO2) en los recién nacidos que requieren ventilación permitiría evitar hipocapnia e hipercapnia. La medición de CO2 espirada (ETCO2) es una alternativa poco implementada en esta población. Objetivo: Evaluar la relación entre la ETCO2 y la PCO2 en recién nacidos Métodos: Estudio de corte transversal, comparativo entre dos métodos de medición de PCO2, el convencional mediante análisis de muestras sanguíneas y el estimado mediante ETCO2. Se incluyeron recién nacidos internados que requerían ventilación mecánica convencional. La medición de ETCO2 se realizó mediante un ventilador neonatal Graph Net Neo – TECME®, con capnógrafo incorporado y se obtuvo el gradiente ETCO2 – PCO2. Se realizaron análisis de correlación y gráficos de Bland Altman para estimar la concordancia. Resultados: Se analizaron 277 muestras (ETCO2 / PCO2) en 83 recién nacidos. Los valores promedios de ETCO2 y PCO2 fueron de 41.36 mmHg y 42.04 mmHg, Hubo correlación positiva y significativa entre ETCO2 y PCO2 en el análisis global (r = 0,5402; p ETCO2) en 2 de las unidades mientras que en la tercera la diferencia fue negativa (PCO2 < ETCO2) Discusión: La correlación entre ETCO y PCO2 es significativa, si bien los valores obtenidos no resultan equivalentes y la diferencia varía entre 0,1 mmHg a 20 mmHg. Asimismo, observamos errores sistemáticos de signo diferente (positivo o negativo) entre las instituciones.

The consequences of aneuploidy have traditionally been studied in cell and animal models in which the extrachromosomal DNA is from the same species. Here, we explore a fundamental question concerning the impact of aneuploidy on systemic metabolism using a non-mosaic transchromosomic mouse model (TcMAC21) carrying a near-complete human chromosome 21. Independent of diets and housing temperatures, TcMAC21 mice consume more calories, are hyperactive and hypermetabolic, remain consistently lean and profoundly insulin sensitive, and have a higher body temperature. The hypermetabolism and elevated thermogenesis are likely due to a combination of increased activity level and sarcolipin overexpression in the skeletal muscle, resulting in futile sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) activity and energy dissipation. Mitochondrial respiration is also markedly increased in skeletal muscle to meet the high ATP demand created by the futile cycle and hyperactivity. This serendipitous discovery provides proof-of-concept that sarcolipin-mediated thermogenesis via uncoupling of the SERCA pump can be harnessed to promote energy expenditure and metabolic health.

Analyzing the spatial association pattern among species can help to better understanding the mechanisms that drive forest dynamics and assembly. We applied techniques of spatial point pattern analysis to data from a fully mapped plot of tropical dry forest (TDF) in Colombia to assess the spatial association network among the eight most abundant species and we tested the hypothesis that species traits related to the ability to cope with drought stress could explain the observed spatial association patterns. We conducted three analyses, first we classified the types of spatial association patterns of species pairs against a null model of spatial independence, second, we used a heterogeneous Poisson (HP) null-model to assess competitive and facilitative interactions, and finally, we integrated the spatial association network with a traits space spanned by hydraulic functional traits. Overall, the proportion of significant negative and positive associations were low and we found at smaller spatial scales (5 m) prevalence of positive association patterns (11%) and at intermediate scales (16 m) negative interactions (13%). The dominant, evergreen and bird-dispersed species Trichilia oligofoliata, which followed a hydraulically save strategy, was involved in most positive associations at small scales, whereas the evergreen large statured species Aspidosperma polyneuron, which also follows a conservative resource-use strategy, was involved in most negative interactions. In TDFs where water stress is prevalent, tree community assembly and spatial patterns formation are regulated by environmental heterogeneity (e.g., topography), and both facilitative and competitive processes act simultaneously, but at different spatial scales and involving different species. Our findings highlight the potential importance of the examined association patterns, not only for our understanding of community assembly, but also to provide restoration directions.

Accurate estimations of aboveground biomass (AGB) in tropical forests are crucial for maintaining carbon stocks and ensuring effective forest management. By combining remote sensing (RS) data with ensemble algorithms, reliable AGB estimates in forests can be obtained. In this context, the freely available Sentinel-1 (S-1 SAR) and Sentinel 2 multispectral imagery (S-2 MSI) data have a significant role in enhancing accurate AGB estimations at a lower cost, which is relevant for the tropical dry forest (TDF) regions where AGB estimation is uncertain or there is a lack of comprehensive exploration. This study aims to address this gap by presenting a cost-effective and reliable AGB estimation approach in the TDF region of Colombia. For this purpose, we modeled and compared the performance of two ensemble algorithms, random forest (RF) and extreme gradient boosting (XGBoost), to estimate AGB using three predictor categories (polarizations/textures, spectral bands/vegetation indices, and a combination of both). We then examined the modeling potential of S-1 SAR and S-2 MSI imagery in predicting forest AGB and subsequently identified the most suitable variables. To construct AGB models’ field data, we employed a clustered distributed sampling approach involving 100 subsample plots, each with an area of 400 m2. Stepwise multiple linear regression was applied to identify suitable predictors from the original satellite bands, vegetation indices, and texture metrics. To produce a map of AGB, predicted AGB values were calculated for every pixel within a specific satellite subscene using the most effective ensemble algorithm. Our study findings show that the RF model, which employed combined predictor sets, displayed superior performance when evaluated against the independent validation set. The RF model successfully estimated AGB with a high degree of accuracy, achieving an R2 value of 0.78 and an RMSE value of 42.25 Mg/ha−1. In contrast, the XGBoost model performed less accurately, obtaining an R2 value of only 0.60 and an RMSE value of 48.41 Mg/ha−1. The results also indicate that S-2 vegetation indices data were more appropriate for this purpose than S-1 texture data. Despite this, S-1 cross-polarized textures were necessary during the dry season for the combined datasets. The top predictive variables for S-2 images were cab and cw, as well as red-edge bands during the wet season. As for S-1 images, texture D_VH _Hom during the dry season was the most important variable for explaining performance. Overall, the proposed approach of using freely available Sentinel data seems to improve the accuracy of AGB estimation in heterogeneous forest cover and, as such, they should be recommended as a data source for forest AGB assessment.

Lifestyle is different in arid and semi-arid zones. However, where people are born and live have a lasting influence on their social and environmental exposure. This review focuses on the, various dimensions of environmental health imbalance inequality especially in significant environmental sources such as (ie, air, water, soil) among provinces that creates a big health gap in the center, East and the Southeast of Iran. Thus, the population of the arid and semi-arid zones of Iran is facing respiratory, cardiovascular, cancer and infection diseases linked to environmental problems such as chemical and microbial pollution due to air pollution and unsafe water sources, respectively. The prevalence of certain types of cancer such as skin, stomach, bladder, prostate and colorectal cancer together with some respiratory and cardiovascular diseases in arid and semiarid zones such as Kerman, Yazd, etc., has been reported in comparison with other provinces frequently. These impacts have effects on multiple levels of health security in those zones. Based on these concerns, we propose key questions that should guide research in the context of the socio environmental science to support science-based management actions in Iran and other similar semi-arid areas worldwide.

BackgroundWith the emergence of the COVID-19 pandemic, increasing numbers of cases of the multisystem inflammatory syndrome in children (MIS-C) have been reported worldwide; however, it is unclear whether this syndrome has a differential pattern in children from Latin America and the Caribbean (LAC). We conducted a systematic review and meta-analysis to analyze the epidemiological, clinical, and outcome characteristics of patients with MIS-C in LAC countries.MethodsA systematic literature search was conducted in the main electronic databases and scientific meetings from March 1, 2020, to June 30, 2021. Available reports on epidemiological surveillance of countries in the region during the same period were analyzed.ResultsOf the 464 relevant studies identified, 23 were included with 592 patients with MIS-C from LAC. Mean age was 6.6 years (IQR, 6–7.4 years); 60% were male. The most common clinical manifestations were fever, rash, and conjunctival injection; 59% showed Kawasaki disease. Pool proportion of shock was 52%. A total of 47% of patients were admitted to the pediatric intensive care unit (PICU), 23% required mechanical ventilation, and 74% required vasoactive drugs. Intravenous gamma globulin alone was administered in 87% of patients, and in combination with steroids in 60% of cases. Length of hospital stay was 10 days (IQR, 9–10) and PICU stay 5.75 (IQR, 5–6). Overall case fatality ratio was 4% and for those hospitalized in the PICU it was 7%.ConclusionLimited information was available on the clinical outcomes. Improvements in the surveillance system are required to obtain a better epidemiologic overview in the region.

Background: Rehabilitation is still the only treatment available to improve functional status after the acute phase of stroke. Most clinical guidelines highlight the need to design rehabilitation treatments considering starting time, intensity, and frequency, according to the tolerance of the patient. However, there are no homogeneous protocols and the biological effects are under investigation.Objective: To investigate the impact of rehabilitation intensity (hours) after stroke on functional improvement and serum angiogenin (ANG) in a 6-month follow-up study.Methods: A prospective, observational, longitudinal, and multicenter study with three cohorts: strokes in intensive rehabilitation therapy (IRT, minimum 15 h/week) vs. conventional therapy (NO-IRT,

Cierto es que la utilización de técnicas de descentralización productiva no se limita al sector privado, sino que también ha penetrado y cuenta ya con general y fuerte implantación en el sector público, en el que llega a estar presente en casi todas sus actividades, tanto en las precisas para el funcionamiento ordinario de las entidades que lo componen (vigilancia, limpieza de locales, mantenimiento de instalaciones y equipos, gestión administrativa, etc.), como en las necesarias para dispensar servicios de interés general a los ciudadanos. No menos verdad resulta que esta gestión indirecta ha conllevado una acusada devaluación de las condiciones laborales de los trabajadores al servicio de las empresas contratistas o concesionarias ante la generalización de procesos de licitación low prize, participados por empresas multiservicios, las cuales, aprovechando la ausencia de una normativa ad hoc, se caracterizan por la reducción de los costes salariales y otros estándares laborales. Ante esta realidad, no puede sino valorarse de forma positiva la apuesta que desde la Ley 9/2017, de Contratos del Sector Público, se ha realizado en aras a garantizar el cumplimiento de los convenios colectivos sectoriales, siendo necesario, no obstante, que el legislador laboral proporcione cumplida respuesta a las lagunas todavía existentes, sobre todo en los supuestos de subcontratación, donde las responsabilidades empresariales quedan ampliamente diluidas.

Biological invasions pose a serious threat to native semi-arid areas of Brazil, especially in areas of the state of Ceará that are typically invaded byCryptostegia madagascariensis, an exotic plant species from Madagascar. However, how this biological invasion influences the composition of the arbuscular mycorrhizal fungal (AMF) community and how this affects further invasion by C. madagascariensis is not well known. Here we tested how inoculation with species of AMF affects the development of this invasive plant. We analyzed and compared the AMF community composition of four different stages of biological invasion by C. madagascariensis, and examined the effects of inoculation with these four AMF communities, plus a dominant AMF species (Rhizoglomus intraradices) on plant dry biomass, root colonization, plant phosphorous concentration, and plant responsiveness to mycorrhizas of plants of C. madagascariensis. We found that all studied treatments (except the inoculum from the native plant root zone) promoted the growth of C. madagascariensis and lead to a higher P concentration. Our results demonstrate that the invader might be altering the composition of the AMF community in field conditions, because inoculation with this community enhanced invader growth, root colonization, and P uptake.

Copper (Cu) has emerged as an important modifier of body lipid metabolism. However, how Cu contributes to the physiology of fat cells remains largely unknown. We found that adipocytes require Cu to establish a balance between main metabolic fuels. Differentiating adipocytes increase their Cu uptake along with the ATP7A-dependent transport of Cu into the secretory pathway to activate a highly up-regulated amino-oxidase copper-containing 3 (AOC3)/semicarbazide-sensitive amine oxidase (SSAO); in vivo, the activity of SSAO depends on the organism's Cu status. Activated SSAO oppositely regulates uptake of glucose and long-chain fatty acids and remodels the cellular proteome to coordinate changes in fuel availability and related downstream processes, such as glycolysis, de novo lipogenesis, and sphingomyelin/ceramide synthesis. The loss of SSAO-dependent regulation due to Cu deficiency, limited Cu transport to the secretory pathway, or SSAO inactivation shifts metabolism towards lipid-dependent pathways and results in adipocyte hypertrophy and fat accumulation. The results establish a role for Cu homeostasis in adipocyte metabolism and identify SSAO as a regulator of energy utilization processes in adipocytes.

Background: Rehabilitation therapy is the only available treatment for stroke survivors presenting neurological deficits; however, the underlying molecules and mechanisms associated with functional/motor improvement during rehabilitation are poorly understood.Objective: Our aim is to study the modulation of angiogenin and endothelial progenitor cells (EPCs) as repair-associated factors in a cohort of stroke patients and mouse models of rehabilitation after cerebral ischemia.Methods: The clinical study included 18 ischemic strokes admitted to an intensive rehabilitation therapy (IRT) unit, 18 non-ischemic controls and brain samples from three deceased patients. Angiogenin and EPCs were measured in blood obtained before and up to 6 months after IRT together with an extensive evaluation of the motor/functional status. In parallel, C57BL/6 mice underwent middle cerebral artery occlusion, and the pasta matrix reaching-task or treadmill exercises were used as rehabilitation models. Angiogenin RNA expression was measured after 2 or 12 days of treatment together with cell counts from EPCs cultures.Results: Brain angiogenin was identified in both human and mouse tissue, whereas serum levels increased after 1 month of IRT in association with motor/functional improvement. EPC populations were increased after stroke and remained elevated during follow-up after IRT. The mouse model of rehabilitation by the task-specific pasta matrix exercise increased the number of EPCs at 2 days and increased angiogenin expression after 12 days of rehabilitation.Conclusions: Angiogenin and EPCs are modulated by rehabilitation after cerebral ischemia, suggesting that both angiogenin and EPCs could serve as biomarkers of improvement during rehabilitation or future therapeutic targets.

Developing accurate methods to map vegetation structure in tropical forests is essential to protect their biodiversity and improve their carbon stock estimation. We integrated LIDAR (Light Detection and Ranging), multispectral and SAR (Synthetic Aperture Radar) data to improve the prediction and mapping of canopy height (CH) at high spatial resolution (30 m) in tropical forests in South America. We modeled and mapped CH estimated from aircraft LiDAR surveys as a ground reference, using annual metrics derived from multispectral and SAR satellite imagery in a dry forest, a moist forest, and a rainforest of tropical South America. We examined the effect of the three forest types, five regression algorithms, and three predictor groups on the modelling and mapping of CH. Our CH models reached errors ranging from 1.2−3.4 m in the dry forest and 5.1−7.4 m in the rainforest and explained variances from 94−60% in the dry forest and 58−12% in the rainforest. Our best models show higher accuracies than previous works in tropical forests. The average accuracy of the five regression algorithms decreased from dry forests (2.6 m +/− 0.7) to moist (5.7 m +/− 0.4) and rainforests (6.6 m +/− 0.7). Random Forest regressions produced the most accurate models in the three forest types (1.2 m +/− 0.05 in the dry, 4.9 m +/− 0.14 in the moist, and 5.5 m +/− 0.3 the rainforest). Model performance varied considerably across the three predictor groups. Our results are useful for CH spatial prediction when GEDI (Global Ecosystem Dynamics Investigation lidar) data become available.

Objetivo: Valorar el comportamiento oftalmológico de la retinosis pigmentaria en la consulta de baja visión del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en el año 2010. Métodos: Se realizó un estudio descriptivo, transversal de 27 pacientes con retinosis pigmentaria y baja visión. Se analizaron variables como: edad, sexo, examen oftalmológico que incluyó agudeza visual mejor corregida y campo visual. Se clasificaron los pacientes de acuerdo con el estadio clínico, debut de la enfermedad, ayudas ópticas y no ópticas más utilizadas. Los resultados fueron expresados en números de casos y valor porcentual. Se utilizó el estadígrafo x2 para el análisis y se aceptó como error tipo I una P menor o igual a 0,05. Resultados: Se observó que 85 % de los pacientes se encontraban en el intervalo de 15 a 45 años de edad. Predominó el estadio I y el debut precoz. La ayuda óptica más utilizada fue el microscopio, y no ópticas, la iluminación y los filtros. Conclusión: No existió relación en nuestro estudio entre la forma de debut de la enfermedad con el estadio clínico de los pacientes presumiblemente por el diagnóstico precoz de la enfermedad y el tratamiento oportuno. La rehabilitación visual fue aceptada en todos los casos estudiados.Objective: To evaluate the behavior of Retinitis Pigmentosa in low vision service at “Ramón Pando Ferrer" Cuban Institute of Ophthalmology. Methods: A cross sectional study of 27 patients with retinitis pigmentosa and low vision was undertaken. The analyzed variables included age, sex, eye examination that included best-corrected visual acuity and visual field. Patients were classified according to clinical stage and disease onset and most used optical and non optical devices. The results were expressed in numbers of cases and percentages. The x2 statistic was used for the analysis of results. And Type I error was accepted as p= 0,05. Results: It was observed that 85 % of patients were in the 15 to 45 age group; the stage I and early onset predominated, the most widely used optical devices was the microscope, and the non-optical ones were lighting and filters. Conclusions: There was no relationship in our study between the onset of the disease and the clinical stage of patients, presumably due to early disease diagnosis and timely treatment. Visual rehabilitation was accepted in all studied cases.

Experimental visceral leishmaniasis (VL) represents an exquisite model to study CD8(+) T cell responses in a context of chronic inflammation and antigen persistence, since it is characterized by chronic infection in the spleen and CD8(+) T cells are required for the development of protective immunity. However, antigen-specific CD8(+) T cell responses in VL have so far not been studied, due to the absence of any defined Leishmania-specific CD8(+) T cell epitopes. In this study, transgenic Leishmania donovani parasites expressing ovalbumin were used to characterize the development, function, and fate of Leishmania-specific CD8(+) T cell responses. Here we show that L. donovani parasites evade CD8(+) T cell responses by limiting their expansion and inducing functional exhaustion and cell death. Dysfunctional CD8(+) T cells could be partially rescued by in vivo B7-H1 blockade, which increased CD8(+) T cell survival but failed to restore cytokine production. Nevertheless, B7-H1 blockade significantly reduced the splenic parasite burden. These findings could be exploited for the design of new strategies for immunotherapeutic interventions against VL.

A major restriction in predicting plant community response to future climate change is a lack of long-term data needed to properly assess species and community response to climate and identify a baseline to detect climate anomalies. Here, we use a 106-year dataset on a Sonoran Desert plant community to test the role of extreme temperature and precipitation anomalies on community dynamics at the decadal scale and over time. Additionally, we tested the climate sensitivity of 39 desert plant species and whether sensitivity was associated with growth form, longevity, geographic range, or local dominance. We found that desert plant communities had shifted directionally over the 106 years, but the climate had little influence on this directional change primarily due to nonlinear shifts in precipitation anomalies. Decadal-scale climate had the largest impact on species richness, species relative density, and total plant cover, explaining up to 26%, 45%, and 55% of the variance in each, respectively. Drought and the interaction between the frequency of freeze events and above-average summer precipitation were among the most influential climate factors. Increased drought frequency and wetter periods with frequent freeze events led to larger reductions in total plant cover, species richness, and the relative densities of dominant subshrubs Ambrosia deltoidea and Encelia farinosa. More than 80% of the tested species were sensitive to climate, but sensitivity was not associated with a species' local dominance, longevity, geographic range, or growth form. Some species appear to exhibit demographic buffering, where when they have a higher sensitivity to drought, they also tend to have a higher sensitivity to favorable (i.e., wetter and hotter) conditions. Overall, our results suggest that, while decadal-scale climate variation substantially impacts these desert plant communities, directional change in temperature over the last century has had little impact due to the relative importance of precipitation and drought. With projections of increased drought in this region, we may see reductions in total vegetation cover and species richness due to the loss of species, possibly through a breakdown in their ability to demographically buffer climatic variation, potentially changing community dynamics through a change in facilitative and competitive processes. [ABSTRACT FROM AUTHOR]

The general objective of the study is to study the degree of gender-based violence that exists among students at the University of Huelva. The sample of 678 students (540 women and 138 men) answered an anonymous and voluntary questionnaire, which was made up of several validated questionnaires. The results show that many of the students have rarely suffered or carried out any type of violent behavior in their relationships, although there is a very low percentage who claim to have suffered gender-based violence, so we can affirm that it is a phenomenon present to a greater or lesser extent. It is observed that students easily relate physical aggressions to gender-based violence while they hesitate to relate psychological aggressions to it. This difficulty can be supported by other studies that state that adolescents believe that some actions of psychological violence—such as being jealous—are simply signs of love. This is compounded by the large number of romantic myths that are increasingly spread through social networks, media, family patterns, etc. More educational interventions are therefore needed to prevent these outcomes from leading to unhealthy relationships disguised as excessive romanticism.

Abstract Background Marine sponges and their microbiomes are ecosystem engineers distributed across the globe. However, most research has focused on tropical and temperate sponges, while polar regions like Antarctica have been largely neglected. Despite its harsh conditions and geographical isolation, Antarctica is densely populated by sponges. In this study, we explored the extent of habitat specificity in the diversity, community composition, and microbial co-occurrence within Antarctic sponge microbiomes, in comparison to those from other marine environments. We used massive sequencing of 16S rRNA genes and integrated multiple databases to incorporate Antarctic sponges as a habitat in global microbiome analyses. Results Our study revealed significant differences in microbial diversity and community composition between Antarctic and non-Antarctic sponges. We found that most microorganisms present in Antarctic sponges are unique to the South Shetland Islands. Nitrosomonas oligotropha, Candidatus Nitrosopumilus, Polaribacter, SAR116 clade, and Low Salinity Nitrite-Oxidizing Bacteria (LS-NOB) are microbial members characterizing the Antarctic sponge microbiomes. Based on their exclusivity and presence across different sponges worldwide, we identified habitat-specific and habitat-generalist bacteria associated with each habitat. They are particularly abundant and connected within all the Antarctic sponges, suggesting that they may play a crucial role as keystone species within these sponge ecosystems. Conclusions This study provides significant insights into the microbial diversity and community composition of sponges in Antarctica and non-Antarctic ecoregions. Our findings provide evidence for habitat-specific patterns that differentiate the microbiomes of Antarctic sponges from elsewhere, indicating the strong influence of environmental selection and dispersal limitation wrapped into the Antarctic ecoregions to shape more similar microbial communities in distantly related sponges. This study contributes to understanding signatures of microbial community assembly in the Antarctic sponges and has important implications for the ecology and evolution of these unique marine environments.

Abstract Understanding how biotic interactions shape ecosystems and impact their functioning, resilience and biodiversity has been a sustained research priority in ecology. Yet, traditional assessments of ecological complexity typically focus on species-species interactions that mediate a particular function (e.g., pollination), overlooking both the synergistic effect that multiple functions might develop as well as the resulting species-function participation patterns that emerge in ecosystems that harbor multiple ecological functions. Here we propose a mathematical framework that integrates various types of biotic interactions observed between different species. Its application to recently collected data of an islet ecosystem—reporting 1537 interactions between 691 plants, animals and fungi across six different functions (pollination, herbivory, seed dispersal, decomposition, nutrient uptake, and fungal pathogenicity)—unveils a non-random, nested structure in the way plant species participate across different functions. The framework further allows us to identify a ranking of species and functions, where woody shrubs and fungal decomposition emerge as keystone actors whose removal have a larger-than-random effect on secondary extinctions. The dual insight—from species and functional perspectives—offered by the framework opens the door to a richer quantification of ecosystem complexity and to better calibrate the influence of multifunctionality on ecosystem functioning and biodiversity.

Synergic effects between climate change and invasive species may alter soil microbial diversity and functioning, as well as cause major shifts in physicochemical properties. Moreover, some of these ecological impacts may manifest even after the removal of the invasive species. We have conducted a field experiment to assess such effects on soil microbial communities (fungi and bacteria) and physicochemical properties seven months after the removal of Carpobrotus edulis (L.), an invasive plant of coastal dune ecosystems. C. edulis grew on the experimental plots for 14 months under current (“invasive species treatment”) and increased warming and drought conditions (“combined treatment”). Then, all plant parts (above and belowground biomass) were removed with a non-aggressive eradication method and soil samples were collected seven months later in the experimental and control plots (no invasive species and current climatic conditions). We predicted a general compositional shift in microbial communities in response to the presence of the invasive species. Moreover, given that water is the most limiting factor in this type of ecosystem, we also predicted a more pronounced compositional shift in the treatment combining invader presence and climate change. While species richness was similar amongst treatments, we observed some taxonomic and functional variation in soil microbial communities. Notably, fungal and bacterial communities exhibited contrasting responses. The species composition of bacteria differed significantly between the “invasive species” and “control” treatments, while, in the case of fungi, the most substantial difference occurred between the “invasive species” treatment and the combined treatment of “invasive species and climate change”. Some chemical properties, such as carbon and nitrogen content or pH, strongly differed amongst treatments, with the “invasive species” showing a different response compared to the other two treatments. Overall, our study suggests smaller short-term effects on the microbial community compared to soil chemical properties. Furthermore and contrary to our initial expectations, the potential impact on the soil microbiome seemed to be weaker in the face of rising temperatures and drought conditions predicted by climate change. This outcome highlights the remarkable complexity of the impact of invasive species and climate change on belowground microbial communities.

Background Marine sponges are dominant components of Antarctic benthos and representative of the high endemism that characterizes this environment. All microbial groups are part of the Antarctic sponge holobionts, but microbial eukaryotes have been studied less, and their symbiotic role still needs to be better understood. Here, we characterize the dynamics of microbial eukaryotes associated with Antarctic sponges, focusing on dinoflagellates over three summer periods to better understand the members, interannual variations, and trophic and lifestyle strategies. Results The analysis revealed that dinoflagellates dominate microeukaryotic communities in Antarctic sponges. The results also showed significant differences in the diversity and composition of dinoflagellate communities associated with sponges compared to those in seawater. Antarctic sponges were dominated by a single dinoflagellate family, Syndiniales Dino-Group-I-Clade 1, which was present in high abundance in Antarctic sponges compared to seawater communities. Despite minor differences, the top microeukaryotic amplicon sequence variants (ASVs) showed no significant interannual abundance changes, indicating general temporal stability within the studied sponge species. Our findings highlight the abundance and importance of parasitic groups, particularly the classes Coccidiomorphea, Gregarinomorphea, and Ichthyosporea, with the exclusive dominance of Syndiniales Dino-Group-I-Clade 1 within sponges. Conclusions The present study comprehensively characterizes the microbial eukaryotes associated with Antarctic sponges, showing a remarkable stability of parasitic dinoflagellates in Antarctic sponges. These findings underscore the significant role of parasites in these marine hosts, with implications for population dynamics of the microeukaryome and the holobiont response to a changing ocean.

The West Kallaallit Nunaat (Greenland) coast, characterized by a variety of fjords, bays, and channels influenced by glacier melting and Atlantic and Arctic waters, is one of the most affected ecosystems by climate change. Here, we combine oceanography, optics, microscopy, high throughput sequencing, microalgal strain establishments, and state-of-the-art analytical methods to fully characterize the diversity, community composition, and toxin repertoire of the eukaryotic plankton members of the coast of the West Kalaallit Nunaat (Greenland). Results indicate that the West Kalaallit Nunaat (Greenland) coast is a complex and oceanographically challenging system, where the superimposition of water masses of different origins, the penetration of light and its repercussions, generate mainly vertical, rather than horizontal heterogeneity in nutrient concentration and plankton biomass. Nevertheless, our molecular data reveal a strong homogeneity and a high diversity in the plankton community along the Greenland coast. We confirmed the presence of five phycotoxin groups: domoic acid and paralytic shellfish toxins were most abundant along the transect from Qeqertarsuup Tunua (Disko Bay) to the northern Baffin Bay, while spirolides, yessotoxins and pectenotoxins were predominant in Nuup Kangerlua (GodthaabFjord) and Qeqertarsuup Tunua (Disko Bay). Concentrations of these phycotoxins correlate differently to temperature, salinity and nutrients, reflecting the ecological differences of their producers. Patterns of paralytic shellfish and spirolide toxins suggest the presence of genetically distinct populations of Alexandrium along the Western Kalaallit Nunaat (Greenland). Phytoplankton strains isolated during this oceanographic campaign resemble, in most cases, the toxin profiles of the respective field stations. Overall, this work shows the diversity and community composition of the plankton at the Western Kalaallit Nunaat coast and reveals a distinct spatial distribution of phycotoxins, with certain toxin groups restricted to specific areas.