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A trait-based ecological perspective on the soil microbial antibiotic-related genetic machinery
Antibiotic resistance crisis dictates the need for resistance monitoring and the search for new antibiotics. The development of monitoring protocols is hindered by the great diversity of resistance factors, while the "streetlight effect" denies the possibility of discovering novel drugs based on existing databases. In this study, we address these challenges using high-throughput environmental screening viewed from a trait-based ecological perspective. Through an in-depth analysis of the metagenomes of 658 topsoil samples spanning Europe, we explored the distribution of 241 prokaryotic and fungal genes responsible for producing metabolites with antibiotic properties and 485 antibiotic resistance genes. We analyzed the diversity of these gene collections at different levels and modeled the distribution of each gene across environmental gradients. Our analyses revealed several nonparallel distribution patterns of the genes encoding sequential steps of enzymatic pathways synthesizing large antibiotic groups, pointing to gaps in existing databases and suggesting potential for discovering new analogues of known antibiotics. We show that agricultural activity caused a continental-scale homogenization of microbial antibiotic-related machinery, emphasizing the importance of maintaining indigenous ecosystems within the landscape mosaic. Based on the relationships between the proportion of the genes in the metagenomes with the main predictors (soil pH, land cover type, climate temperature and humidity), we illustrate how the properties of chemical structures dictate the distribution of the genes responsible for their synthesis across environments. With this understanding, we propose general principles to facilitate the discovery of antibiotics, including principally new ones, establish abundance baselines for antibiotic resistance genes, and predict their dissemination
Effects of plant diversity on productivity strengthen over time due to trait-dependent shifts in species overyielding
Plant diversity effects on community productivity often increase over time. Whether the strengthening of diversity effects is caused by temporal shifts in species-level overyielding (i.e., higher species-level productivity in diverse communities compared with monocultures) remains unclear. Here, using data from 65 grassland and forest biodiversity experiments, we show that the temporal strength of diversity effects at the community scale is underpinned by temporal changes in the species that yield. These temporal trends of species-level overyielding are shaped by plant ecological strategies, which can be quantitatively delimited by functional traits. In grasslands, the temporal strengthening of biodiversity effects on community productivity was associated with increasing biomass overyielding of resource-conservative species increasing over time, and with overyielding of species characterized by fast resource acquisition either decreasing or increasing. In forests, temporal trends in species overyielding differ when considering above- versus belowground resource acquisition strategies. Overyielding in stem growth decreased for species with high light capture capacity but increased for those with high soil resource acquisition capacity. Our results imply that a diversity of species with different, and potentially complementary, ecological strategies is beneficial for maintaining community productivity over time in both grassland and forest ecosystems
Urban densification considering sense of place and environmental justice – or not
Rapid urbanisation is a major transformative driving force of continuous and contested changes in socio-spatial urban structure. Such changes can lead to sociospatial injustice especially when they involve marginalised populations. Managing rapid urbanisation thus requires goal-oriented inclusive urban planning and policies to secure sustainable development. The theory of environmental justice, as distributive justice, recognition justice, and procedural justice, has been developed in urban planning literature. The experience of justice – or the lack thereof – also affects sense of place, which in relation to urban change includes how people experience, relate to and create meaning in urban spaces. This thesis aims to deepen the understanding of the interplay between sense of place and issues of environmental justice in relation to urban densification in Swedish stigmatised neighbourhoods. The thesis is based on a case study with multiple sampling techniques: document analysis, visual discourse analysis, photo elicitation, and interviews with residents, planners and stakeholders. The first paper focuses on the role of media in creating discourses concerning e.g. safety and security and how these discourses impact the creation of socio-spatial injustice. The second paper concentrates on the impact of an urban densification project to shed light on issues of environmental justice and public participation. In the third paper, the concept of sense of densification is introduced, and it examines how densification projects affect residents’ lives, both in outcomes and as processes. The thesis concludes that the combined knowledge about sense of place and environmental justice research from an urban planning standpoint can provide a greater understanding of how to motivate residents to act collectively to improve their community and participate in local planning processes. This is important for planners and stakeholders, in order to strengthen a sustainable planning and design process by understanding and honouring the value of local meanings of places
Future climate impacts of sodium-ion batteries
Sodium-ion batteries (SIBs) have emerged as an alternative to lithium-ion batteries (LIBs) due to their promising performance in terms of battery cycle lifetime, safety, operating in wider temperature range, as well as the abundant and low-cost of sodium resources. This study evaluated the climate impacts of three SIBs, and compared to two LIBs under four scenarios with considering potential changes in battery performance and background productions between 2020 and 2050. To ensure a fair comparison, all batteries were modeled in the 21,700 form, and a battery dimensioning model was developed to calculate the required amount of components for each battery. We found that equal to lower GHG emissions result from the use of SIBs compared to LIBs under optimal performance scenarios. From 2020 to 2050, the climate impacts of SIBs decreased by 43-57 %. The relative contribution of the battery manufacturing process decreases from 18-32 % to 2-4 % due to the increasingly share of clean energy in the electricity grid, while the relative contribution of key battery component materials increases over time, especially for cathode active materials. These results emphasize the significance of decarbonizing the electric grid, and suggest that future investment in SIBs is promising from an environmental point of view
Distance functions of carabids in crop fields depend on functional traits, crop type and adjacent habitat: a synthesis
Natural pest and weed regulation are essential for agricultural production, but the spatial distribution of natural enemies within crop fields and its drivers are mostly unknown. Using 28 datasets comprising 1204 study sites across eight Western and Central European countries, we performed a quantitative synthesis of carabid richness, activity densities and functional traits in relation to field edges (i.e. distance functions). We show that distance functions of carabids strongly depend on carabid functional traits, crop type and, to a lesser extent, adjacent non-crop habitats. Richness of both carnivores and granivores, and activity densities of small and granivorous species decreased towards field interiors, whereas the densities of large species increased. We found strong distance decays in maize and vegetables whereas richness and densities remained more stable in cereals, oilseed crops and legumes. We conclude that carabid assemblages in agricultural landscapes are driven by the complex interplay of crop types, adjacent non-crop habitats and further landscape parameters with great potential for targeted agroecological management. In particular, our synthesis indicates that a higher edge-interior ratio can counter the distance decay of carabid richness per field and thus likely benefits natural pest and weed regulation, hence contributing to agricultural sustainability
Disparities in Body Color Adaptability and Ambient Light Color Preference between Wild and Hatchery-Reared Marbled Rockfish (Sebastiscus marmoratus)
Hatchery rearing significantly influences the phenotypic development of fish, with potential adverse effects for the post-release performance of hatchery-reared individuals in natural environments, especially when targeted for stock enhancement. To assess the suitability of releasing hatchery-reared fish, a comprehensive understanding of the phenotypic effects of captive rearing, through comparisons with their wild conspecifics, is essential. In this study, we investigated the divergence in body coloration between wild and hatchery-reared marbled rockfish Sebastiscus marmoratus. We examined the selection preferences for different light colors and assessed the impact of different ambient light colors on the morphological color-changing ability of juvenile marbled rockfish. Our findings revealed significant differences in body color between wild and hatchery-reared marbled rockfish. The hue and saturation values of wild marbled rockfish were significantly higher than those of their hatchery-reared counterparts, indicative of deeper and more vibrant body coloration in the wild population. Following a ten-day rearing period under various light color environments, the color of wild marbled rockfish remained relatively unchanged. In contrast, hatchery-reared marbled rockfish tended to change their color, albeit not reaching wild-like coloration. Light color preference tests demonstrated that wild juvenile marbled rockfish exhibited a preference for a red-light environment, while hatchery-reared individuals showed a similar but weaker response. Both wild and hatchery-reared marbled rockfish displayed notable negative phototaxis in the presence of yellow and blue ambient light. These results highlight the impact of hatchery rearing conditions on the body color and morphological color-changing ability, and provide insight into light color selection preferences of marbled rockfish. To mitigate the divergence in phenotypic development and produce more wild-like fish for stocking purposes, modifications to the hatchery environment, such as the regulation of ambient light color, should be considered
Quantitative and qualitative saccharide analysis of North Atlantic brown seaweed by gas chromatography/mass spectrometry and infrared spectroscopy
Brown seaweeds contain a variety of saccharides which have potential industrial uses. The most abundant polysaccharide in brown seaweed is typically alginate, consisting of mannuronic (M) and guluronic acid (G). The ratio of these residues fundamentally determines the physicochemical properties of alginate. In the present study, gas chromatography/mass spectrometry (GC/MS) was used to give a detailed breakdown of the monosaccharide species in North Atlantic brown seaweeds. The anthrone method was used for determination of crystalline cellulose. The experimental data was used to calibrate multivariate prediction models for estimation of total carbohydrates, crystalline cellulose, total alginate and alginate M/G ratio directly in dried, brown seaweed using three types of infrared spectroscopy, using relative error (RE) as a measure of predictive accuracy. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) performed well for the estimation of total alginate (RE = 0.12, R2 = 0.82), and attenuated total reflectance (ATR) showed good prediction of M/G ratio (RE = 0.14, R2 = 0.86). Both DRIFTS, ATR and near infrared (NIR) were unable to predict crystalline cellulose and only DRIFTS performed better in determining total carbohydrates. Multivariate spectral analysis is a promising method for easy and rapid characterization of alginate and M/G ratio in seaweed
Effect of cellulose-rich fibres on faba bean protein gels is determined by the gel microstructure
Increased consumption of plant-based foods and better utilisation of side-streams can reduce the environmental impact of food consumption. A promising crop for production of protein-rich plant-based foods is faba bean, which can serve as a local alternative to soy in cold-climate regions. This study investigated faba bean protein gelation at multiple pH values and the effect of adding a fibre-rich side-stream from protein extraction. Two different sources were used to extract the fibre (cotyledon and hull). The gels were characterised in terms of textural properties, microstructure and water mobility. Gels produced at pH 4 and 5 showed reduced fracture stress, fracture strain and water-holding capacity, but higher Young's modulus, than gels produced at pH 7. The effect of adding fibre (at fixed solids content) varied with pH. Differences observed were attributed to the gel microstructure, as light and scanning electron micrographs showed coarse, aggregated microstructure at pH 4 and 5 and a fine-stranded protein network at pH 7. Irrespective of fibre source (cotyledon/hull), addition of fibre had comparable effects on textural properties. Low-field NMR revealed differences in water mobility between gels at pH 4-5 versus pH 7, and between gels with/without added fibre, likely related to contrasting microstructures and the water-binding properties of the fibre fractions
Real-time water quality forecasting in rivers using satellite data and dynamic models: an online system for operational management, control and citizen science
Increasingly scarce water resources and growing global populations have exacerbated the problems of water quality in river systems and freshwaters in general. New monitoring methodologies and tools to democratize access to water quality information are needed if we are to reach ambitious societal objectives such as the UN Sustainable Development Goals and the European Green Deal. Here we present a cloud-based system for producing publicly accessible real time water quality forecasts coupled to novel biosensor technology. Short term forecasts of water quality impairments, e.g., as cyanobacteria blooms, sediment plumes and toxic pollution incidents are increasingly relevant both to citizens and stakeholders. Here, we present a new cloud based system that utilizes satellite data to produce real time forecasts of flow and water quality using a chain of dynamic catchment-scale models at multiple locations in a river network. We demonstrate this new system using two case studies: the River Thames and the Essex Colne River (United Kingdom). These rivers are key water supply sources for London and South-East England, respectively and are of high interest to recreational water users. We show how the new system can predict and forecast water quality, estimate toxicity and connect to citizen science observations using an App (www.aquascope.com) for information synthesis and delivery
Exploring desired urban futures: the transformative potential of a nature-based approach*
Amidst multiple crises and calls for transformative change, the demand to reassess human-nature relationships has increased. Rethinking the future of cities is vital in this process, yet positive urban visions prioritizing nature beyond human-centred perspectives are lacking. To address this gap, we propose a "nature-based desired futures" approach for envisaging and building collective discussion around transformative change. We explore four concepts underpinning (i) why such alternative urban futures are needed (human-nature disconnect and changing urban imaginaries) and (ii) how they might be approached (transformative change and leverage, and the 'education of desire'). This provides the basis for a participatory approach that adapts the Three Horizon method to explore desired urban futures for nature in 2050. Six workshops involving 111 participants linked to 'Conexus', a project on nature-based solutions in European and Latin American cities, explored emerging desired futures, evolving ideas of nature, human-nature relationships, and agency. The approach offers space for reflection creative exploration, and weaving together of new, hopeful, caring, emancipatory stories. Its effectiveness hinges on the mutually reinforcing power of deep leverage, and of structural, systemic, and enabling approaches, to give purpose and direction to the exploration of desired futures