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Ongoing global warming is expected to augment soil respiration by increasing microbial activity, driving self-reinforcing feedback to climate change. However, the compensatory thermal adaptation of soil microorganisms and substrate depletion may weaken the effects of rising temperature on soil respiration. To test this hypothesis, we collected soils along a large-scale forest transect in eastern China spanning a natural temperature gradient, and incubated the soils at different temperatures with or without substrate addition. We combined the exponential thermal response function and a data-driven model to study the interaction effect of thermal adaptation and substrate availability on microbial respiration and compared our results to those from two additional continental and global independent datasets. Modelled results suggested that the effect of thermal adaptation on microbial respiration was greater in areas with higher mean annual temperatures, consistent with the compensatory response to warming. In addition, the effect of thermal adaptation on microbial respiration was greater under substrate addition than under substrate depletion, which was also true for the independent datasets reanalyzed using our approach. Our results indicate that thermal adaptation in warmer regions could exert a more pronounced negative impact on microbial respiration when substrate availability is abundant. These findings improve the body of knowledge on how substrate availability influences soil microbial community-temperature interactions, which could improve estimates of projected soil carbon losses to the atmosphere through respiration.

We identified groups of mayfly species that share microhabitats in eastern Cuban streams by sampling during rainy and dry seasons in four microhabitats in pools (cobbles, sand, leaf litter and bank vegetation) and one microhabitat (cobbles) in riffles. A total of 20 species and three morphospecies were found. Species similarity in habitat use was analysed using k-means clustering. Overall, the highest number of individuals was collected in cobbles in riffles, followed by cobbles in pools. Five species groups, labelled from I to V, were identified based on their primary microhabitat use. Two groups (I and V) included species with a generalist pattern of habitat use, but differing in seasonality. Species in remaining groups tend to concentrate in specific microhabitats. Species of groups II and IV use mostly cobbles in riffles and in pools, respectively, while species in group III concentrate in sand during the rainy season. Our results allowed to identify the species most vulnerable to alterations of the hydrologic regimen.

The accumulation of human-derived waste on our coasts is an escalating phenomenon, yet the relative importance and potential interactions among its main drivers are not fully understood. We used citizen-science standardized collections to investigate how anthropogenic and environmental factors influence the level, composition, and temporal variation of beach debris. An average of 58 kg and 803 items/100 m, dominated by single-use items of land (rather than sea) origin, were collected in the 881 beaches sampled. Interactions between anthropogenic and environmental factors (e.g., human use × beach substrate) were the strongest predictors of beach debris, accounting for 34% of the variance explained in its amount and composition. Beach debris showed a highly stochastic temporal variation (adjusted R2 = 0.05), partly determined by interactions between different local and landscape anthropogenic pressures. Our results show that both environmental and anthropogenic factors (at the local and landscape scale) co-determine the level and composition of beach debris. We emphasize the potential of citizen-science to inform environmental policy, showing that land-originated single-use items dominate beach debris, and the importance of considering their multiple anthropogenic and environmental drivers to improve our low predictive power regarding their spatio-temporal distribution.

The increasing trend in sea surface temperature promotes the spread of Vibrio species, which are known to cause diseases in a wide range of marine organisms. Among these pathogens, Vibrio mediterranei has emerged as a significant threat, leading to bleaching in the coral species Oculina patagonica. Bacteriophages, or phages, are viruses that infect bacteria, thereby regulating microbial communities and playing a crucial role in the coral’s defense against pathogens. However, our understanding of phages that infect V. mediterranei is limited. In this study, we identified two phage species capable of infecting V. mediterranei, utilizing a combination of cultivation and metagenomic approaches. These phages are low-abundance specialists within the coral mucus layer that exhibit rapid proliferation in the presence of their hosts, suggesting a potential role in coral defense. Additionally, one of these phages possesses a conserved domain of a leucine-rich repeat protein, similar to those harbored in the coral genome, that plays a key role in pathogen recognition, hinting at potential coral-phage coevolution. Furthermore, our research suggests that lytic Vibrio infections could trigger prophage induction, which may disseminate genetic elements, including virulence factors, in the coral mucus layer. Overall, our findings underscore the importance of historical coral-phage interactions as a form of coral immunity against invasive Vibrio pathogens.

Climate change is increasing the frequency and severity of short-term (~1 y) drought events—the most common duration of drought—globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function—aboveground net primary production (ANPP)—was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought.

Determining the structure and fuel load is key to know the flammability of vegetation in the Mediterranean Basin where forest fires are frequent. Determine which plant structural variable is best related to living and dead fuel to develop allometric equations in nine species in the Western Mediterranean Basin. In the east of the Iberian Peninsula (Valencia Province), we measured four structural variables (basal stem diameter, height, maximum diameter and perpendicular diameter) that were related, by means of allometric equations, to the living and dead fuel separated into different size classes. We also analyze fuel changes across developmental states of the studied species, and the vertical distribution of dead fuel. General equations that consider all development states can be used to determine living fuel. However to obtain dead fuel, we recommend using specific equations for each development state and fuel fraction for better accuracy. The basal stem diameter was the best structural variable in almost all cases for estimating fuel in the studied species. Dead fuel load throughout species’ ontological development is a key factor to manage Mediterranean plant communities.

Microplastics (MPs) accumulation in rocky shore organisms has limited knowledge. This study investigated MPs accumulation in filter-feeding oysters, herbivorous limpets and carnivorous snails to assess their performance as sentinel species in the MPs trophic transfer. The samples were obtained along a contamination gradient in the Santos Estuarine System, Brazil. All three studied species showed MPs concentrations related to the contamination gradient, being the oysters the species that showed the highest levels, followed by limpets and snails (average of less and most contaminated sites of 1.06–8.90, 2.28–5.69 and 0.44–2.10 MP g−1, respectively), suggesting that MPs ingestion rates are linked to feeding habits. MPs were mainly polystyrene and polyacetal. The polymer types did not vary among sites nor species. Despite minor differences in percentages and diversity of size, shape, and color classes, the analyzed species were equally able to demonstrate dominance of small, fiber, transparent, black and blue MPs. Thus, oysters, limpets, and snails are proposed as sentinels of MPs in monitoring assessments.

Forest restoration is a suitable tool to mitigate land degradation and enhance the supply of vital goods and services. Social participation in forest restoration has gained increasing interest. Yet, the impact of participation on people's perception of ecological restoration and the restoration process has barely been addressed despite its relevance for the long-term success of restoration actions. We assessed mutual learning of different stakeholder groups in a ten-year demonstration project, and its potential to foster continued participatory forest restoration in Beni Boufrah valley, a semiarid area located in North Morocco. We performed face-to-face interviews to assess post-restoration individual learning for a subset of 15 highly engaged stakeholders using five components of social learning: reciprocal determinism, self-reflective capability, expectations, self-regulation and locus of control. Furthermore, we organized a workshop to assess collective learning in the study area. The lessons learnt by the project team was described using monitoring vegetation measurements, field visits and meetings, and stakeholder recommendations. Two thirds of the stakeholders showed an increasing awareness of the reciprocal relationship between people and the environment, while recognizing the inappropriateness of current behaviors and practices. Farmers showed continuous mistrust towards the Forestry Agency which justifies the need for more innovative approaches to resolve persistent conflicts, integrate forest and agricultural interventions and establish new mechanisms for economic motivation. Stakeholders acquired theoretical and practical concepts on forest restoration, but self-initiated activities were scarce and reinforcement of environmental awareness is still needed. There was a high impact of drought on seedling survival and growth along with a decrease in stakeholder engagement over the years. We could identify and implement a series of practical corrective measure

Blida (Algeria) is characterized by a high level of seismic exposure and vulnerability due to its dense population and the presence of aging buildings. The historical earthquake that occurred in 1825, with a moment magnitude (Mw7.1), underscored the urgent need for a thorough assessment of seismic risk in the area. Here, an extensive study conducted in downtown of the city of Blida to evaluate seismic risk and its consequences is presented. Geounits 141 and 148 emerged as the most severely affected in all the simulated earthquake scenarios indicating severe damage and casualties mainly for closest earthquakes (Blida and Bounaian, both with moment magnitude Mw7.1) but also for furthest earthquakes as Mouzaia El Affroun (Mw6.6), and Hammam Melouane (Mw.5). The sensitivity analysis demonstrated the importance of the selection of the performance point computation method (improved displacement coefficient method -IDCM, modified capacity spectrum-MADRS, and nonlinear analysis method-N2) and the choice of the ground motion prediction equation. IDCM results are less influenced by the choice of the GMPE, but they provide higher damage results expressed as a mean damage ratio. Moreover, the study estimated potential human impacts in the Blida region, highlighting varying levels of impact on different geounits under different earthquake scenarios. The study's primary findings from seismic risk assessments in the studied region highlight its high susceptibility to earthquakes and can be summarized as follows: The mean damage ratio will be 52.6% ± 1.4%, 50.9% ± 1.6%; 31.8% ± 3.4% and 21.4% ± 3.1% for the Blida, Bounaian, Mouzaia El Affroun and Hammam Melouane earthquakes respectively.

Microplastic pollution is becoming a continuously growing environmental concern, while bivalve mollusks are particularly vulnerable due to their sessile habits and feeding through water filtration processes. Microplastic incidence in soft tissues of the clam Amarilladesma mactroides was assessed along unconsolidated substrates distributed in extensive coastal regions of southern Brazil. Influence of urbanization levels, distance to rivers and local hydrodynamics on microplastic accumulation by the clam was tested. The average concentration of microplastics was high (3.09 ± 2.11 particles.g−1), considering 16 sampled sites. Particles were mainly composed by polyamide, polyethylene and polyethylene terephthalate, while were mainly smaller, fibrous and colorless. High urbanization and closer proximity to rivers insured higher contamination, which is a trend observed globally. No influence of coastal hydrodynamics was seen. Considering obtained findings, A. mactroides presents good potential to be used as a valuable tool to assess microplastic contamination in unconsolidated substrates of beach areas.

Soil fungi are a key constituent of global biodiversity and play a pivotal role in agroecosystems. How arable farming affects soil fungal biogeography and whether it has a disproportional impact on rare taxa is poorly understood. Here, we used the high-resolution PacBio Sequel targeting the entire ITS region to investigate the distribution of soil fungi in 217 sites across a 3000 km gradient in Europe. We found a consistently lower diversity of fungi in arable lands than grasslands, with geographic locations significantly impacting fungal community structures. Prevalent fungal groups became even more abundant, whereas rare groups became fewer or absent in arable lands, suggesting a biotic homogenization due to arable farming. The rare fungal groups were narrowly distributed and more common in grasslands. Our findings suggest that rare soil fungi are disproportionally affected by arable farming, and sustainable farming practices should protect rare taxa and the ecosystem services they support.

Climate change has been shown to alter the spatial distribution of whales and other marine mammals. Fast changing ocean temperatures may also affect the spatial distribution of whales at a finer scale, namely within populations, including aggregation behaviour. Our ability to analyze the impact of climate change on whale aggregation behavior, however, has been limited by our ability to collect spatial observation data over large areas. To overcome this limitation, this study analyzed open-access satellite imagery obtained between 2007 and 2020 in Canada, Russia, and Alaska using Deep Convolutional Neural Networks (CNN) to detect 1,980 beluga whales in 11 populations and to quantify their aggregation patterns within their populations. Subsequently, we examined the relationship between sea surface temperature (SST) and the intra-population spatial patterns of beluga whales during summer seasons, when these whales normally aggregate. We detected a negative correlation between SST and the frequency of beluga whale aggregation, suggesting that warming temperatures may impact beluga whale spatio-behavioral dynamics. Considering that the relative abundance of beluga whales is declining and the future SST projections in these Arctic Ocean locations, climate change may pose yet another threat to beluga whales and other ice-dependent species.

Self-organized spatial patterns are a common feature of complex systems, ranging from microbial communities to mussel beds and drylands. While the theoretical implications of these patterns for ecosystem-level processes, such as functioning and resilience, have been extensively studied, empirical evidence remains scarce. To address this gap, we analyzed global drylands along an aridity gradient using remote sensing, field data, and modeling. We found that the spatial structure of the vegetation strengthens as aridity increases, which is associated with the maintenance of a high level of soil multifunctionality, even as aridity levels rise up to a certain threshold. The combination of these results with those of two individual-based models indicate that self-organized vegetation patterns not only form in response to stressful environmental conditions but also provide drylands with the ability to adapt to changing conditions while maintaining their functioning, an adaptive capacity which is lost in degraded ecosystems. Self-organization thereby plays a vital role in enhancing the resilience of drylands. Overall, our findings contribute to a deeper understanding of the relationship between spatial vegetation patterns and dryland resilience. They also represent a significant step forward in the development of indicators for ecosystem resilience, which are critical tools for managing and preserving these valuable ecosystems in a warmer and more arid world.

Biodiversity typically increases multiple ecosystem functions simultaneously (multifunctionality) but variation in the strength and direction of biodiversity effects between studies suggests context dependency. To determine how different factors modulate the diversity effect on multifunctionality, we established a large grassland experiment manipulating plant species richness, resource addition, functional composition (exploitative vs. conservative species), functional diversity and enemy abundance. We measured ten above- and belowground functions and calculated ecosystem multifunctionality. Species richness and functional diversity both increased multifunctionality, but their effects were context dependent. Richness increased multifunctionality when communities were assembled with fast-growing species. This was because slow species were more redundant in their functional effects, whereas different fast species promoted different functions. Functional diversity also increased multifunctionality but this effect was dampened by nitrogen enrichment and enemy presence. Our study suggests that a shift towards fast-growing communities will not only alter ecosystem functioning but also the strength of biodiversity-functioning relationships.

Understanding soil microbial populations influencing biogeochemical cycles with potential implications for greenhouse gas (GHG) fluxes emissions is crucial. Methanotrophic, nitrifying and N2O-reducing microorganisms are major drivers of CH4 and N2O fluxes in soils. The metabolism of these organisms relies on enzymes that require as cofactors metal ions scarcely available in the soil, such as copper (Cu) and zinc (Zn). Despite the importance of these ions, how their concentrations relate to the abundance of these microbes at the global scale has not been addressed yet. Here, we used data from a global survey carried out in 47 drylands from 12 countries to evaluate the role of soil Cu and Zn concentrations, and their relationship with aridity, as drivers of the abundance of methanotrophs, archaeal and bacterial nitrifiers, and N2O reducers. To do so, we performed qPCR analyses of the marker genes pmoA, archaeal and bacterial amoA and nosZI. We did not find an association between the abundance of methanotrophs and Cu or Zn availability. However, our results highlight the importance of Cu influencing the abundance of nitrifying bacteria and N2O reducers, two main actors involved in the N2O cycle. Our findings indicate that dryland soils can be prone to reduce the N2O coming from nitrification to innocuous N2, but reductions in soil Cu availability (e.g., by increased aridity conditions due to climate change) could shift this trend.

1. Local and landscape diversity loss, habitat fragmentation and land-use changes commonly co-occur and impair ecosystem multifunctionality, yet they are often studied in isolation. Therefore, we ignore the relative importance of these drivers of ecosystem change or whether or not they interact to determine ecosystem functioning. 2. We measured how changes in local (plant richness) and landscape (different land uses) diversity, land use (orchards, shrubland, pine, oak and mixed forests) and habitat sise, and their interactions, affected the functioning of Mediterranean ecosystems. At 49 plots, we measured 17 above- and below-ground functions, related to nutrient cycling, carbon sequestration and biotic interactions. Additionally, we generated different combinations of plots to compose artificial landscapes where multifunctionality and biodiversity conservation can be maximised, in order to aid land managers to preserve or design functional and diverse areas. 3. The relative importance of local and landscape attributes varied slightly depending on the target function, yet land use was by far the strongest predictor of most functions and multifunctionality above local plant biodiversity, habitat sise or landscape diversity. Oak and mixed forest were the most multifunctional land uses but were functionally wcomplemented by other land uses that maximised some individual functions. 4. The relative proportion of each land use within optimal landscapes varied if the target was biodiversity conservation (with an even dominance of land uses), carbon stocks or multifunctionality (highly dominated by native oak and mixed forests). 5. Synthesis and applications: Our results highlight the importance of remnant native forest to provide multiple ecosystem functions and the potential to restore them and complement these uses with sustainable agriculture. By merging landscape and ecosystem approaches we provide specific numbers regarding the proportion that each land use should have

Mineral-associated organic carbon (MAOC) constitutes a major fraction of global soil carbon and is assumed less sensitive to climate than particulate organic carbon (POC) due to protection by minerals. Despite its importance for long-term carbon storage, the response of MAOC to changing climates in drylands, which cover more than 40% of the global land area, remains unexplored. Here we assess topsoil organic carbon fractions across global drylands using a standardized field survey in 326 plots from 25 countries and 6 continents. We find that soil biogeochemistry explained the majority of variation in both MAOC and POC. Both carbon fractions decreased with increases in mean annual temperature and reductions in precipitation, with MAOC responding similarly to POC. Therefore, our results suggest that ongoing climate warming and aridification may result in unforeseen carbon losses across global drylands, and that the protective role of minerals may not dampen these effects.

Ecological restoration is imperative for controlling desertification. Potential natural vegetation (PNV), the theoretical vegetation succession state, can guides near-natural restoration. Although a rising transition from traditional statistical methods to advanced machine learning and deep learning is observed in PNV simulation, a comprehensive comparison of their performance is still unexplored. Therefore, we overview the performance of PNV mapping in terms of 12 commonly used methods with varying spatial scales and sample sizes. Our findings indicate that the methodology should be carefully selected due to the variation in performance of different model types, with Area Under the Curve (AUC) values ranging from 0.65 to 0.95 for models with sample sizes up to 80% of the total sample size. Specifically, semi-supervised learning performs best with small sample sizes (i.e., 10 to 200), while Random Forest, XGBoost, and artificial neural networks perform better with large sample sizes (i.e., over 500). Further, the performance of all models tends to improve significantly as the sample size increases and the grain size of the crystals becomes smaller. Take the downstream Tarim River Basin, a hyper-arid region undergoing ecological restoration, as a case study. We showed that its potential restored areas were overestimated by 2–3 fold as the spatial scale became coarser, revealing the caution needed while planning restoration projects at coarse resolution. These findings enhance the application of PNV in the design of restoration programs to prevent desertification.

Global concern about plastic pollution is forcing new policies and modifications of human consumption as well as promoting new research lines aiming at the replacement of non-degradable plastics with other polymers more environmentally friendly. Addressing food waste and promoting circular economy strategies, among other approaches, are crucial in reducing environmental impacts and fostering sustainability in several sectors like the agri-food industry. The European Union’s Circular Economy Action Plan is a significant initiative in this direction. Biotechnological processes, especially the valorisation of agri-food waste to produce highly marketed biomolecules like poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) using microorganisms as cellular factories, offer promising avenues for achieving these goals. PHBV is a biodegradable polymer firstly characterised as an isolated biopolymer from bacterial biomass. This biopolymer shows interesting physicochemical properties making possible immense potential in various applications due to its biocompatibility and sustainability, thus revealing it as a good candidate to replace plastics produced by chemical synthesis from petroleum (which are highly recalcitrant and consequently pollutants). This review critically analyses the PHBV synthesis and end-of-life scenarios from their synthesis using chemical and biological pathways, through the forms of biotechnological operation and production, to the forms described until the moment of recycling.

Research carried out in drylands over the last decade has provided major insights on the biodiversity–ecosystem functioning relationship (BEFr) and about how biodiversity interacts with other important factors, such as climate and soil properties, to determine ecosystem functioning and services. Despite this, there are important gaps in our understanding of the BEFr in drylands that should be addressed by future research. In this perspective we highlight some of these gaps, which include: 1) the need to study the BEFr in bare soils devoid of perennial vascular vegetation and biocrusts, a major feature of dryland ecosystems, 2) evaluating how intra-specific trait variability, a key but understudied facet of functional diversity, modulate the BEFr, 3) addressing the influence of biotic interactions on the BEFr, including plant–animal interactions and those between microorganisms associated to biocrusts, 4) studying how differences in species–area relationships and beta diversity are associated with ecosystem functioning, and 5) considering the role of temporal variability and human activities, both present and past, particularly those linked to land use (e.g., grazing) and urbanization. Tackling these gaps will not only advance our comprehension of the BEFr but will also bolster the effectiveness of management and ecological restoration strategies, crucial for safeguarding dryland ecosystems and the livelihoods of their inhabitants.

Human activities are a significant contributor to the spread of antibiotic resistance genes (ARGs), which pose a serious threat to human health. These ARGs can be transmitted through various pathways, including air, within the context of One Health. This study used metagenomics to monitor the resistomes in urban air from two critical locations: a wastewater treatment plant and a hospital, both indoor and outdoor. The presence of cell-like structures was confirmed through fluorescence microscopy. The metagenomic analysis revealed a wide variety of ARGs and a high diversity of antibiotic-resistant bacteria in the airborne particles collected. The wastewater treatment plant showed higher relative abundances with 32 ARG hits per Gb and m3, followed by the main entrance of the hospital (indoor) with ≈5 ARG hits per Gb and m3. The hospital entrance exhibited the highest ARG richness, with a total of 152 different ARGs classified into nine categories of antibiotic resistance. Common commensal and pathogenic bacteria carrying ARGs, such as Moraxella, Staphylococcus and Micrococcus, were detected in the indoor airborne particles of the hospital. Interestingly, no ARGs were shared among all the samples analysed, indicating a highly variable dynamic of airborne resistomes. Furthermore, the study found no ARGs in the airborne viral fractions analysed, suggesting that airborne viruses play a negligible role in the dissemination of ARGs.

Soil salinization poses a significant threat to agricultural productivity, necessitating innovative agronomic strategies to mitigate its impact. This study focuses on improving salt stress resistance in tomato plants through the application of silicon (Si) in roots. A greenhouse experiment was carried out under normal conditions (control, and 1 and 4 mM Si) and under salinity stress (salt control, and 1 and 4 mM Si). Various parameters were analyzed in leaves and roots. Under normal conditions, tomato plants grown in non-saline conditions exhibited some toxicity when exposed to Na2SiO3. As for the experiments under salt stress conditions, Si mitigated oxidative damage, preserving root cell membrane integrity. The concentration of malondialdehyde was reduced by 69.5%, that of proline was reduced by 56.4% and there was a 57.6% decrease in catalase activity for tomato plants treated with 1 mM Si under salt stress. Furthermore, Fe uptake and distribution, under salt conditions, increased from 91 to 123 mg kg−1, the same concentration as that obtained for the normal control. In all cases, the lower dose produced better results under normal conditions than the 4 mM dose. In summary, this research provides a potential application of Si in non-fertigated crop systems through a radicular pathway.

The Random Variable Transformation (RVT) technique has been applied in recent years to analyze a wide variety of dynamic models formulated via random differential equations. The applicability of this technique has usually been focused on problems where an explicit solution of the underlying deterministic problem is available. This fact limits the usefulness of the RVT method. This note aims to point out that the RVT technique can be successfully applied without this requirement by showing a wider range of potential applications including very general classes of single-species models.

Soils support a vast amount of carbon (C) that is vulnerable to climatic and anthropogenic global change stressors (for example, drought and human-induced nitrogen deposition). However, the simultaneous effects of an increasing number of global change stressors on soil C storage and persistence across ecosystems are virtually unknown. Here, using 1,880 surface soil samples from 68 countries across all continents, we show that increases in the number of global change stressors simultaneously exceeding medium–high levels of stress (that is, relative to their maximum levels observed in nature) are negatively and significantly correlated with soil C stocks and mineral association across global biomes. Soil C is particularly vulnerable in low-productivity ecosystems (for example, deserts), which are subjected to a greater number of global change stressors exceeding medium–high levels of stress simultaneously. Taken together, our work indicates that the number of global change stressors is a crucial factor for soil C storage and persistence worldwide.

One of the major processes that affect land is Land Degradation. More precisely, according to the United Nations, Land Degradation means "reduction or loss of biological or economic productivity and complexity of rainfed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from land uses or from a process or combination of processes, including processes arising from human activities and habitation patterns, such as: (i) soil erosion caused by wind and/or water; (ii) deterioration of the physical, chemical and biological or economic properties of soil; and, (iii) long-term loss of natural vegetation. Land degradation, therefore, includes processes that lead to surface salt accumulation and waterlogging associated with salt-affected areas." (United Nations 2007).

Denitrification, a crucial biochemical pathway prevalent among haloarchaea in hypersaline ecosystems, has garnered considerable attention in recent years due to its ecological implications. Nevertheless, the underlying molecular mechanisms and genetic regulation governing this respiration/detoxification process in haloarchaea remain largely unexplored. In this study, RNA-sequencing was used to compare the transcriptomes of the haloarchaeon Haloferax mediterranei under oxic and denitrifying conditions, shedding light on the intricate metabolic alterations occurring within the cell, such as the accurate control of the metal homeostasis. Furthermore, the investigation identifies several genes encoding transcriptional regulators and potential accessory proteins with putative roles in denitrification. Among these are bacterioopsin-like transcriptional activators, proteins harboring a domain of unknown function (DUF2249), and cyanoglobin. In addition, the study delves into the genetic regulation of denitrification, finding a regulatory motif within promoter regions that activates numerous denitrification-related genes. This research serves as a starting point for future molecular biology studies in haloarchaea, offering a promising avenue to unravel the intricate mechanisms governing haloarchaeal denitrification, a pathway of paramount ecological importance.

Los escarabajos peloteros se consideran un taxón útil para describir patrones espaciales y temporales de biodiversidad. Este estudio se llevó a cabo durante 18 meses, en un gradiente altitudinal, de la cuenca del Oglán Alto, situada en la provincia de Pastaza, Ecuador. Se recolectaron un total de 10.227 individuos pertenecientes a 59 especies. Se analizó la preferencia alimentaria y se observó que las especies de escarabajos coprófagos son superiores a las especies necrófagas y generalistas. El grupo funcional de los cavadores fue más abundante que rodadores y moradores. Los efectos de la altitud y precipitación sobre la diversidad de escarabajos estercoleros se analizó mediante modelos lineales generalizados. Se utilizaron seis estimadores de riqueza para comparar los dos tipos de cebo utilizados (excremento y carroña). Se realizó un análisis de correspondencia, según los tipos de trampas y especies capturadas, con respecto a la variación del gradiente altitudinal. Se concluyó que la riqueza y abundancia de los escarabajos peloteros se ven influencias negativamente con la altitud y la precipitación. Pero, el grupo de cavadores evidenciaron una influencia positiva con la precipitación. Aunque la relación de gradiente altitudinal y promedio de riqueza por trampas es muy similar en el gradiente altitudinal muestreado, mostrando una mezcla de especies de escarabajos copronecrófagos asociados a tierras bajas amazónicas, con pocas especies de bosque siempreverde de piedemonte del oriente ecuatoriano. Se recomienda continuar los estudios en este tipo de vegetación, principalmente en un gradiente altitudinal mayor., Dung beetles are considered a useful taxon to describe and to monitor spatial and temporal patterns of biodiversity. This study was carried out over 18 months, on an altitudinal gradient in the Oglán Alto watershed, located in Pastaza Province, Ecuador. A total of 10,227 individuals belonging to 59 species were collected. Food preference was analyzed and it was observed that species of coprophagous beetles are superior to necrophagous and generalists species. Tunnelers functional group was more abundant than rollers and dwellers groups. The effects of altitude and precipitation on dung beetle diversity were analyzed using generalized linear models. Six richness estimators were used for comparison between the two types of bait used (excrement and carrion). Correspondence analysis was performed, according to the types of traps and species captured, with respect to the variation of altitudinal gradient. We concluded that the richness and abundance of dung beetles are negatively influenced by altitude and precipitation. However, the group of tunnelers evidenced a positive influence on precipitation. Although the relation of altitudinal gradient and average of richness by traps is very similar in the altitudinal gradient sampled, showing a mixture of species of copronecrophagous beetles associated to Amazon lowlands, with few species of foothill evergreen forest of the Ecuadorian east. It is recommended to continue studies in this type of vegetation, mainly in a higher altitudinal gradient.

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.

Background Anthropogenic activities significantly contribute to the dissemination of antibiotic resistance genes (ARGs), posing a substantial threat to humankind. The development of methods that allow robust ARG surveillance is a long-standing challenge. Here, we use city-scale monitoring of ARGs by using two of the most promising cutting-edge technologies, digital PCR (dPCR) and metagenomics. Methods ARG hot-spots were sampled from the urban water and wastewater distribution systems. Metagenomics was used to provide a broad view of ARG relative abundance and richness in the prokaryotic and viral fractions. From the city-core ARGs in all samples, the worldwide dispersed sul2 and tetW conferring resistance to sulfonamide and tetracycline, respectively, were monitored by dPCR and metagenomics. Results The largest relative overall ARG abundance and richness were detected in the hospital wastewater and the WWTP inlet (up to ≈6,000 ARGs/Gb metagenome) with a large fraction of unclassified resistant bacteria. The abundance of ARGs in DNA and RNA contigs classified as viruses was notably lower, demonstrating a reduction of up to three orders of magnitude compared to contigs associated to prokaryotes. By metagenomics and dPCR, a similar abundance tendency of sul2 and tetW was obtained, with higher abundances in hospital wastewater and WWTP input (≈125–225 ARGs/Gb metagenome). dPCR absolute abundances were between 6,000 and 18,600 copies per ng of sewage DNA (≈105–7 copies/mL) and 6.8 copies/mL in seawater near the WWTP discharging point. Conclusions dPCR was more sensitive and accurate, while metagenomics provided broader coverage of ARG detection. While desirable, a reliable correlation of dPCR absolute abundance units into metagenomic relative abundance units was not obtained here (r2 < 0.4) suggesting methodological factors that introduce variability. Evolutionary pressure does not significantly select the targeted ARGs in natural aquatic environments.

The increasing prevalence of microplastics (MP) in urban environments has raised concerns over their negative effects on ecosystems and human health. Stormwater runoff, and road dust and sediment, act as major vectors of these pollutants into natural water bodies. Sustainable urban drainage systems, such as permeable pavements, are considered as potential tools to retain particulate pollutants. This research evaluates at laboratory scale the efficiency of permeable interlocking concrete pavements (PICP) and porous concrete pavements (PCP) for controlling microplastics, including tire wear particles (TWP) which constitute a large fraction of microplastics in urban environments, simulating surface pollution accumulation and Mediterranean rainfall conditions. Microplastic levels in road dust and sediments and stormwater runoff inputs were 4762 ± 974 MP/kg (dry weight) and 23.90 ± 17.40 MP/L. In infiltrated effluents, microplastic levels ranged from 2.20 ± 0.61 to 5.17 ± 1.05 MP/L; while tire wear particle levels ranged between 0.28 ± 0.28 and 3.30 ± 0.89 TWP/L. Distribution of microplastics within the layers of PICP and PCP were also studied and quantified. Microplastics tend to accumulate on the pavements surface and in geotextile layers, allowing microplastic retention efficiencies from 89 % to 99.6 %. Small sized (< 0.1 mm) fragment shaped microplastics are the most common in effluent samples. The results indicate that permeable pavements are a powerful tool to capture microplastics and tire wear particles, especially by surface and geotextile layers. The study aims to shed light on the complex mobilisation mechanisms of microplastics, providing valuable insights for addressing the growing environmental concern of microplastic pollution in urban areas.

Although usually considered part of the plankton, cubozoans are strong swimmers. The aim of this study was to determine the influence of the active swimming ability of the box jellyfish Carybdea marsupialis on the spatial distribution of a well-studied population in the NW Mediterranean where adults and juveniles do not overlap geographically. To accomplish this, we analyzed the swimming speed, effective velocity, effective displacement index (EDI), and proficiency of 27 individuals with diagonal bell widths (DBWs) ranging from 1.1 to 36 mm. The laboratory analysis utilized conventional video recordings and the video analysis tool Tracker. Mean swimming speed for small juveniles, medium juveniles and adults was 9.7 ± 0.8, 21.9 ± 2.3 and 43.1 ± 1.8 mm s−1 (mean ± se), respectively. Effective velocity was also proportional to size, ranging from 5.0 ± 0.7 to 38.8 ± 3.1 mm s−1 (mean ± se). The calculated EDI for each group was 0.51 ± 0.05, 0.84 ± 0.06 and 0.90 ± 0.05 (mean ± se), respectively. Proficiency showed an inverse trend, from 6.4 ± 0.6 s−1 for the small juveniles to 1.36 ± 0.05 for adults (mean ± se). Comparing the swimming speed results with the local currents obtained from drifting buoys analyzed in the area, adults would be able to swim strongly enough to overcome almost 70% of the currents, whereas the small juveniles would not reach 17%. This would allow larger individuals to select their habitat, while smaller individuals are left dependent on advection. Although experiments adding currents in aquaria would be necessary to confirm these theoretical results, the data obtained would be useful in improving the performance of bio-mathematical models used to predict jellyfish blooms since, even though the sting of C. marsupialis is non-fatal, it may produce systemic effects in sensitive swimmers.

Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in drylands, remain virtually unknown. Here we evaluated the relative importance of grazing pressure and herbivore type, climate and plant functional traits on 24 soil physical and chemical attributes that represent proxies of key ecosystem services related to decomposition, soil fertility, and soil and water conservation. To do this, we conducted a standardized global survey of 288 plots at 88 sites in 25 countries worldwide. We show that aridity and plant traits are the major factors associated with the magnitude of plant effects on fertile islands in grazed drylands worldwide. Grazing pressure had little influence on the capacity of plants to support fertile islands. Taller and wider shrubs and grasses supported stronger island effects. Stable and functional soils tended to be linked to species-rich sites with taller plants. Together, our findings dispel the notion that grazing pressure or herbivore type are linked to the formation or intensification of fertile islands in drylands. Rather, our study suggests that changes in aridity, and processes that alter island identity and therefore plant traits, will have marked effects on how perennial plants support and maintain the functioning of drylands in a more arid and grazed world.

Snake response to habitat changes is frequently investigated at the species level, but it is still poorly known how snakes respond to habitat changes at the community level and at which spatial scale. Here, we used a multi-model inference approach to evaluate the effects of local and landscape composition (percentage of forest cover and silviculture) and habitat fragmentation (number of forest patches and total edge) on species, functional, and phylogenetic diversity of snake communities in tropical fragmented landscapes. Additionally, we tested whether silviculture acted as an environmental filter for snakes. Species and functional diversity responded primarily to landscape elements: species richness, abundance, and functional diversity decreased with deforestation. In addition, species richness and abundance increased with the proportion of forest and the number of patches in the landscape. In contrast, phylogenetic diversity was driven by the local habitat composition. Although habitat types did not filter entire clades and functional groups, each species tended to have a co-occurring species with similar traits (at landscape level) and a close relative (at both levels) in impacted habitats. In contrast, the co-occurrence of close relatives and functionally similar species was avoided in the native forest. Our findings indicate that snake responses to habitat changes occur on multiple scales and highlight the importance of conserving native forests to maintain multiple components of biodiversity. Strategies for conserving snake diversity in tropical fragmented landscapes should therefore consider management practices at both the local and landscape scales.

Climate change is expected to lead to a drier world, with more frequent and severe droughts, constituting a growing threat to biodiversity, especially in drylands. Positive plant−plant interactions, such as nurse plants facilitating beneficiary communities in their understorey, could mitigate such climate-induced stress. However, testing the real-world relevance of nurse facilitation under drought requires accounting for inter actions within the diverse beneficiary communities, which may reduce, or amplify the buffering effect of a nurse. Here, we investigated when and how the interactions among nurse plants and beneficiary community members buffered drought effects in a Mediterranean semiarid abandoned cropland. We transplanted sapling beneficiary communities of either one or three species either under a nurse or in open microsites for different soil moisture levels through watering. Net facilitative effects on survival and biomass were only observed when beneficiary communities were species-diverse and under drought (without watering), meaning that under these conditions, facilitation provided by the nurse had larger positive effects than the negative effects stemming from competition with the nurse and among beneficiary species. Nurses appear to be generating these increases in survival and biomass in drought conditions via two mechanisms commonly associated with watering in open sites: they generate complementarity among the beneficiaries and shift traits to lower stress profiles. Contrasting with watering, which was found to enhance competitive hierarchy, our study shows that nurses appear to alter species dominance, favouring the less competitive species. Our results highlight three mechanisms (complementarity, competitive dominance, and trait plasticity) by which nurse species could mitigate the loss of biodiversity and biomass production due to water stress. Maintaining and supporting nurse species is thus a potentially pivotal approach in the face of projec

The signs of climate change are undeniable, and the impact of these changes on ecosystem function heavily depends on the response of microbes that underpin the food web. Antarctic ice shelf is a massive mass of floating ice that extends from the continent into the ocean, exerting a profound influence on global carbon cycles. Beneath Antarctic ice shelves, marine ice stores valuable genetic information, where marine microbial communities before the industrial revolution are archived. Here, in this proof-of-concept, by employing a combination of single-cell technologiesand metagenomics, we have been able to sequence frozen microbial DNA (≈300 years old) stored in the marine ice core B15 collected from the Filchnner-Ronne Ice Shelf. Metagenomic data indicated that Proteobacteria and Thaumarchaeota (e.g., Nitrosopumilus spp.), followed by Actinobacteria (e.g., Actinomarinales), were abundant. Remarkably, our data allow us to “travel to the past” and calibrate genomic and genetic evolutionary changes for ecologically relevant microbes and functions, such as Nitrosopumilus spp., preserved in the marine ice (≈300 years old) with those collected recently in seawater under an ice shelf (year 2017). The evolutionary divergence for the ammonia monooxygenase gene amoA involved in chemolithoautotrophy was about 0.88 amino acid and 2.8 nucleotide substitution rate per 100 sites in a century, while the accumulated rate of genomic SNPs was 2,467 per 1 Mb of genome and 100 years. Whether these evolutionary changes remained constant over the last 300 years or accelerated during post-industrial periods remains an open question that will be further elucidated.

Drylands account for 45% of the Earth’s land area, supporting approximately 40% of the global population. These regions support some of the most extreme environments on Earth, characterized by extreme temperatures, low and variable rainfall, and low soil fertility. In these biomes, microorganisms provide vital ecosystem services and have evolved distinctive adaptation strategies to endure and flourish in the extreme. However, dryland microbiomes and the ecosystem services they provide are under threat due to intensifying desertification and climate change. In this review, we provide a synthesis of our current understanding of microbial life in drylands, emphasizing the remarkable diversity and adaptations of these communities. We then discuss anthropogenic threats, including the influence of climate change on dryland microbiomes and outline current knowledge gaps. Finally, we propose research priorities to address those gaps and safeguard the sustainability of these fragile biomes.

Context Managing landscapes to increase multiple services provision in search of higher agricultural yield can be an alternative to agricultural intensification. Nonetheless, to properly guide management, we need to better understand how landscape structure affects multiple services at different scales. Objectives Focused on synergies and trade-offs in real-world landscapes, we investigated how and at which scale landscape features related to the supply, demand and flow of services act as a common driver of pollination and pest control in coffee plantations. Methods Considering landscapes in an important coffee-producing region in Brazil, we tested the effects of forest and coffee cover, distance to forest, forest-coffee edge density and coffee edge diversity at multiple scales on pollination and pest control by birds, bats and ants. Results Coffee edge diversity (number of land uses in contact with coffee) was an important driver of pollination and pest control, being consistently relevant at local scales (up to 300 m). However, services were also affected by other landscape features and the ‘scale of effect’ of these relationships varied. Additionally, results show the complex nature of pest control once the direction of effect revealed services and disservices. Conclusions Besides reinforcing the importance of known landscape effects, this study adds to previous studies by showcasing the relevance of diverse land uses around coffee crops as a common driver of pollination and pest control provision by different species. Moreover, we highlight how understanding the combined local and landscape effects may aid in offsetting disservices and tackling the variety of ‘scales of effect’ found.

Despite the considerable research effort devoted to witnessing the reproduction of the emblematic dusky grouper, Epinephelus marginatus, the underwater spawning event has rarely been observed. In this study, we document for the first time the spawning event of the dusky grouper in the Marine Protected Area (MPA) of Cabo de Palos-Islas Hormigas (SE Iberian Peninsula, Spain), which represents the first direct spawning record of the species in the last 20 years. The reproductive event occurred on a seamount located within the buffer protection zone of the MPA. On the evening of July 27, 2021, the spawning of two individuals, displaying silver streaked (male) and uniformly dark (female) colour patterns, was observed using SCUBA diving. The event was filmed and information on the environmental conditions in which reproduction occurred was collected. Success ful spawning was documented at dusk, just one minute before sunset, three days after the full moon and with almost no current. In line with published data, our observation supports sea water temperature and photoperiod as primary potential triggers of dusky grouper reproduction in the Mediterranean. The confirmation of grouper reproduction within a well-enforced MPA established more than 25 years ago suggests that the survival and reproductive output of this large predatory fish may be favoured by protection measures, stressing the critical role of MPAs for maintaining a viable population of this valuable species., Malgré les efforts de recherche considérables consacrés à l’observation de la reproduction de l’emblématique mérou brun, Epinephelus marginatus, la fraie en mer a été rarement observée. Dans cette étude, nous documen tons pour la première fois la fraie du mérou brun dans l’aire marine protégée (AMP) de Cabo de Palos-Islas Hor migas (sud-est de la péninsule Ibérique, Espagne), ce qui représente le premier enregistrement direct de ponte de l’espèce au cours des 20 dernières années. L’événement reproductif a eu lieu sur un socle rocheux situé dans la zone de protection tampon de l’AMP. Dans la soirée du 27 juillet 2021, la fraie de deux individus, l’un affichant les motifs de couleur striée argentée (mâle) et l’autre uniformément sombre (femelle), a été observée en plongée sous-marine. L’événement a été filmé et des informations sur les conditions environnementales dans lesquelles la reproduction a eu lieu ont été recueillies. La ponte effective a été observée au crépuscule, juste une minute avant le coucher du soleil, trois jours après la pleine lune et presque sans courant. En accord avec les données publiées, nos observations confirment que la température de l’eau de mer et la photopériode sont les principaux déclencheurs potentiels de la reproduction du mérou brun en Méditerranée. La confirmation de la reproduction du mérou au sein d’une AMP bien surveillée, établie il y a plus de 25 ans, suggère que la survie et la reproduction de ce grand poisson prédateur peuvent être favorisées par les mesures de protection, soulignant le rôle critique des AMP pour maintenir une population viable de cette espèce de grande valeur.

Haloarchaea are extremophilic microorganisms belonging to the Archaea domain that require high salt concentrations to be alive, thus inhabiting ecosystems like salty ponds, salty marshes, or extremely salty lagoons. They are more abundantly and widely distributed worldwide than initially expected. Most of them are grouped into two families: Halobacteriaceae and Haloferacaceae. The extreme conditions under which haloarchaea survive contribute to their metabolic and molecular adaptations, thus making them good candidates for the design of bioremediation strategies to treat brines, salty water, and saline soils contaminated with toxic compounds such as nitrate, nitrite, oxychlorates such as perchlorate and chlorate, heavy metals, hydrocarbons, and aromatic compounds. New advances in understanding haloarchaea physiology, metabolism, biochemistry, and molecular biology suggest that biochemical pathways related to nitrogen and carbon, metals, hydrocarbons, or aromatic compounds can be used for bioremediation proposals. This review analyses the novelty of the most recent results showing the capability of some haloarchaeal species to assimilate, modify, or degrade toxic compounds for most living beings. Several examples of the role of these microorganisms in the treatment of polluted brine or salty soils are also discussed in connection with circular economy-based processes.

Determining the sources of marine litter is necessary to mitigate this increasing global problem. Plastic bottles are useful tracers of marine litter and constitute the main item (24%) stranding on remote beaches in the Galapagos Islands. The aim of this study was to estimate the abundance of plastic bottles in remote beaches and inferred their sources. To do so, we collected plastic bottles at 60 remote Galapagos Island beaches from 2018 to 2022. 76% of beaches were qualified as badly polluted, with >34 bottles·100 m−1. Most identified bottles came from Peru (71%), followed by China (17%) and Ecuador (9%). Although most locally-sold products are made in Ecuador, they contribute little to beach litter loads. Polyethylene terephthalate bottles with lid (necessary for litter dispersal) represented 88% of all bottles, demonstrating that most of the litter reaching the Galapagos comes from distant sources, mainly from South America. However, bottle ages indicate that at least 10% of Peruvian, 26% of Ecuadorian, and all Chinese bottles likely were dumped from ships. Reducing marine litter reaching the Galapagos Islands requires tackling litter leakage from land-based sources in South America and better compliance with regulations banning the dumping of plastics and other persistent wastes from ships.

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The Euclid mission is expected to image millions of galaxies with high resolution, providing an extensive dataset to study galaxy evolution. We investigate the application of deep learning to predict the detailed morphologies of galaxies in Euclid using Zoobot a convolutional neural network pretrained with 450000 galaxies from the Galaxy Zoo project. We adapted Zoobot for emulated Euclid images, generated based on Hubble Space Telescope COSMOS images, and with labels provided by volunteers in the Galaxy Zoo: Hubble project. We demonstrate that the trained Zoobot model successfully measures detailed morphology for emulated Euclid images. It effectively predicts whether a galaxy has features and identifies and characterises various features such as spiral arms, clumps, bars, disks, and central bulges. When compared to volunteer classifications Zoobot achieves mean vote fraction deviations of less than 12% and an accuracy above 91% for the confident volunteer classifications across most morphology types. However, the performance varies depending on the specific morphological class. For the global classes such as disk or smooth galaxies, the mean deviations are less than 10%, with only 1000 training galaxies necessary to reach this performance. For more detailed structures and complex tasks like detecting and counting spiral arms or clumps, the deviations are slightly higher, around 12% with 60000 galaxies used for training. In order to enhance the performance on complex morphologies, we anticipate that a larger pool of labelled galaxies is needed, which could be obtained using crowdsourcing. Finally, our findings imply that the model can be effectively adapted to new morphological labels. We demonstrate this adaptability by applying Zoobot to peculiar galaxies. In summary, our trained Zoobot CNN can readily predict morphological catalogues for Euclid images., Comment: 27 pages, 26 figures, 5 tables, submitted to A&A

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