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| 2. |
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| 3. |
- Tiegs, Scott D., et al.
(författare)
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Global patterns and drivers of ecosystem functioning in rivers and riparian zones
- 2019
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Ingår i: Science Advances. - Washington : American Association of Advancement in Science. - 2375-2548. ; 5:1
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Tidskriftsartikel (refereegranskat)abstract
- River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.
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| 4. |
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| 5. |
- Axfors, Cathrine, et al.
(författare)
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Association between convalescent plasma treatment and mortality in COVID-19 : a collaborative systematic review and meta-analysis of randomized clinical trials
- 2021
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Ingår i: BMC Infectious Diseases. - : BioMed Central (BMC). - 1471-2334. ; 21:1
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Forskningsöversikt (refereegranskat)abstract
- Background: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, ). Methods: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. Results: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I-2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. Conclusions: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.
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| 6. |
- Costello, David M., et al.
(författare)
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Global patterns and controls of nutrient immobilization on decomposing cellulose in riverine ecosystems
- 2022
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Ingår i: Global Biogeochemical Cycles. - : John Wiley & Sons. - 0886-6236 .- 1944-9224. ; 36:3
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Tidskriftsartikel (refereegranskat)abstract
- Microbes play a critical role in plant litter decomposition and influence the fate of carbon in rivers and riparian zones. When decomposing low-nutrient plant litter, microbes acquire nitrogen (N) and phosphorus (P) from the environment (i.e., nutrient immobilization), and this process is potentially sensitive to nutrient loading and changing climate. Nonetheless, environmental controls on immobilization are poorly understood because rates are also influenced by plant litter chemistry, which is coupled to the same environmental factors. Here we used a standardized, low-nutrient organic matter substrate (cotton strips) to quantify nutrient immobilization at 100 paired stream and riparian sites representing 11 biomes worldwide. Immobilization rates varied by three orders of magnitude, were greater in rivers than riparian zones, and were strongly correlated to decomposition rates. In rivers, P immobilization rates were controlled by surface water phosphate concentrations, but N immobilization rates were not related to inorganic N. The N:P of immobilized nutrients was tightly constrained to a molar ratio of 10:1 despite wide variation in surface water N:P. Immobilization rates were temperature-dependent in riparian zones but not related to temperature in rivers. However, in rivers nutrient supply ultimately controlled whether microbes could achieve the maximum expected decomposition rate at a given temperature. Collectively, we demonstrated that exogenous nutrient supply and immobilization are critical control points for decomposition of organic matter.
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| 7. |
- De Palma, Adriana, et al.
(författare)
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Predicting bee community responses to land-use changes : effects of geographic and taxonomic biases
- 2016
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 6, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises.
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| 8. |
- Garcia, Nicolas Pardo, et al.
(författare)
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Best available technologies for the heat and cooling market in the European Union
- 2012
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Rapport (refereegranskat)abstract
- Every year, over 40% of the total energy consumed in Europe is used for the generation of heat for either domestic or industrial purposes whereas the cooling demand is growing exponentially. The importance of the heat and cooling sector is underlined in the EU energy policy initiatives. This emphasize the role of technologies based on renewable energy sources combined with highefficiency energy technologies, to meet the heat and cooling demand in Europe more sustainably in the future. In this context, the JRC led study, which was undertaken with two partners1, to identify the current best available technologies (BATs) which can contribute to improve the energy efficiency and reduce the CO2 emission in the heat and cooling market in the EU
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| 9. |
- Garcia, Nicolas Pardo, et al.
(författare)
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Heat and cooling demand and market perspective
- 2012
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Rapport (refereegranskat)abstract
- In order to fully understand the national potentials for cogeneration, it is essential to identify the existing and prospective demand of heat and cooling by sector. A study will be performed on a MS level to describe the demand of heat and cooling by different sectors (i.e. industrial, residential), demand types (different temperatures) and supply technologies. This work aims to analyze the current situation and future trends of heat and cooling demand in the EU, as well as, the use and availability of industrial. Within each sector the demand will be presented for different segments. The focus is to map the demand of heat and cooling on temperature intervals possible to be supplied by district heating, district cooling or CHP. In order to capture the characteristics of heat, heat is split into different types; space heating, warm water, cooking, and industrial heat. For cooling, space cooling is the main type applicable to district cooling
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| 10. |
- Hudson, Lawrence N, et al.
(författare)
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The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project
- 2017
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Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 7:1, s. 145-188
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Tidskriftsartikel (refereegranskat)abstract
- The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
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| 11. |
- Hudson, Lawrence N., et al.
(författare)
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The PREDICTS database : a global database of how local terrestrial biodiversity responds to human impacts
- 2014
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4:24, s. 4701-4735
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Tidskriftsartikel (refereegranskat)abstract
- Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - ). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
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| 12. |
- Jörger, Katharina, et al.
(författare)
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MEIOZORES 2019 - EXPLORING THE MARINE MEIOFAUNA OF THE AZORES
- 2021
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Ingår i: AÇOREANA. ; , s. 17-41
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Tidskriftsartikel (refereegranskat)abstract
- In July 2019 an international team of 39 senior and junior researchers from ninecountries met at the University of the Azores in Ponta Delgada, São Miguel for a 10-daysworkshop/ summer school to explore the meiofaunal biodiversity in marine sediments of the Azores. In total, we sampled intertidal and subtidal sediments from 54 localities on 14 major sites around São Miguel and additionally explored eight freshwater and terrestrial sites for rotifers. We sorted and investigated more than 2000 living specimens in the field, yielding approximately 180 species of soft-bodied meiofauna, representing most major clades of meiofauna with a focus on nematodes, polychaete annelids, proseriate andrhabdocoel flatworms, gastrotrichs, acoelomorphs, nemerteans, molluscs and cnidarians. Most of the encountered diversity shows similarities to the North-East Atlantic continental meiofauna, but in-depth morphological and molecular analyses are still pending. About 60 of the 180 species could not be assigned a species-level identification in the field, and nearly 15% of the total diversity is expected to be new to science and is awaiting formal description. Herein, we present an overview of the results of the workshop, providing detailed information on the sampling sites, methodology and encountered diversity, and we offer a preliminary discussion on aspects of faunal elements shared with other biogeographic regions. We highlight the most common members of the marine meiofauna of the Azores, provide preliminary diversity estimates and suggest a roadmap for future research towards a better understanding of the meiofauna in this remote archipelago.
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| 13. |
- Krook-Riekkola, Anna, et al.
(författare)
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SureCity Deliverable 3.1 Outline of the City-level modelling framework
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report refers to Work Package 3. Task 3.1 of the SURECITY project. It presents the first part of the generic TIMES-City model in which the users provide input. The model has been developed for this project and to be implemented in three partner cities, namely, Almada, Judenburg and Malmö.The TIMES-City model represents a generic city energy system; supply technologies and their infrastructure and the demand technologies used in buildings, transportation and industry. The model here presented is the result of the information compiled in Work Package 1 (WP1- User requirements and ICT specification) and Work Package 2 (WP2- Status quo of the demonstration cases). WP1 clarified the needs of the small and medium cities to be modelled and WP2 compiled the available information to be input into the model regarding the status quo of the demonstration sites in terms of energy system and transport infrastructure, usage, GHG emissions and air quality. In this report the existing users and future cities are guided on how to provide input the model. The structure of the files and the data needed for the model are given for the demand sectors mentioned above.All in all, this report defines the demand and supply technologies used in TIMES-City model and how to populate it with the data. Thus, it is a useful manual for the project’s partner cities and future users.
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| 14. |
- Lampinen, Jussi, et al.
(författare)
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Acceptance of near-natural greenspace management relates to ecological and socio-cultural assigned values among European urbanites
- 2021
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791 .- 1618-0089. ; 50, s. 119-131
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Tidskriftsartikel (refereegranskat)abstract
- Grasslands are widespread elements of urban greenspace providing recreational, psychological and aesthetic benefits to city residents. Two urban grassland types of contrasting management dominate urban greenspaces: frequently mown, species-poor short-cut lawns and less intensively managed, near-natural tall-grass meadows. The higher conservation value of tall-grass meadows makes management interventions such as converting short-cut lawns into tall-grass meadows a promising tool for urban biodiversity conservation. The societal success of such interventions, however, depends on identifying the values urban residents assign to different types of urban grasslands, and how these values translate to attitudes towards greenspace management. Using 2027 questionnaires across 19 European cities, we identify the assigned values that correlate with people's personal greenspace use and their preferences for different types of urban grasslands to determine how these values relate to the agreement with a scenario of converting 50% of their cities' short-cut lawns into tall-grass meadows. We found that most people assigned nature-related values, such as wildness, to tall-grass meadows and utility-related values, such as recreation, to short-cut lawns. Positive value associations of wildness and species richness with tall-grass meadows, and social and nature related greenspace activities, positively correlated with agreeing to convert short-cut lawns into tall-grass meadows. Conversely, disapproval of lawn conversion correlated with positive value associations of cleanliness and recreation potential with short-cut lawns. Here, people using greenspaces for nature-related activities were outstandingly positive about lawn conversion. The results show that the plurality of values assigned to different types of urban grasslands should be considered in urban greenspace planning. For example, tall-grass meadows could be managed to also accommodate the values associated with short-cut lawns, such as tidiness and recreation potential, to support their societal acceptance.
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| 15. |
- Pardo-García, Nicolás, et al.
(författare)
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Sustainable and Resource Efficient Cities platform : SureCity holistic simulation and optimization for smart cities
- 2019
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Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 215, s. 701-711
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Tidskriftsartikel (refereegranskat)abstract
- During the last decade, professional analytical tools and platforms are increasingly more used to analyse and support decision-making regarding urban energy systems. Most of existing urban energy platforms are focused on short-term analysis (present or 2020) and cover specific sectors and/or aspects, without considering the holistic optimisation of the whole energy system. Moreover, usually these platforms can only be operated by users with high technical skills. This article presents the design and development of the innovative SureCity Platform which aims to overcome existing gaps to support cities to achieve their mid-to-long term sustainability targets. The main novelties the SureCity platform are: (i) it is a transparent and user-friendly software which can also be used by non-technical staff, such as politicians; (ii) it allows assessment of urban policies and measures through holistic optimisation of the whole energy system towards low carbon energy systems including air quality, land-use and water use at city level. Furthermore, since it is based on a generic comprehensive model, the SureCity platform can be adjusted and applied to a large number of cities. Because it is generalised, it has been developed using a participatory approach with different city stakeholders, and since it is designed to be used by users with different levels of expertise, it can also improve communication among city actors and benchmarking with other cities.
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| 16. |
- Pardo, Nicholas, et al.
(författare)
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Methodology to estimate the energy flows of the European Union heating and cooling market
- 2013
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Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 52, s. 339-352
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Tidskriftsartikel (refereegranskat)abstract
- Over 40% of the total energy consumed in Europe is used for the generation of heat for either domestic or industrial purposes. Meanwhile, the demand for cooling is steadily increasing in all European Member State. In this context, it is essential to identify the heating and cooling demand in the economic sectors. The objective of this study is to propose a methodology to estimate the European heating and cooling demand by country, fuel, economical subsector and activity based on official statistics and reports from resource origin to the customer. The results show that most useful heat energy comes from the direct burn of a fuel principally natural gas. The contribution of the electricity is relatively moderate for the residential and service sectors but low for industrial sector. Most part of the cooling demand is generated by electrical cooling machines (air conditioning and chillers) which extract free environmental energy allowing compensate part of the losses from the electricity production. District heating has a moderate contribution and district cooling can be considered negligible.
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| 17. |
- Peiro, Ana M., et al.
(författare)
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Health-Related Quality of Life in Chronic Pain Treated With Tapentadol Versus Oxycodone/Naloxone and Its Determinants: A Real-World, Single-Center Retrospective Cohort Study in Spain
- 2024
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Ingår i: VALUE IN HEALTH REGIONAL ISSUES. - 2212-1099. ; 44
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: A substantial proportion of patients with chronic noncancer pain (CNCP) are treated with tapentadol (TAP) or oxycodone/naloxone (OXN) to improve their perceived physical and mental health over time. Methods: A cross-sectional study was conducted in 135 CNCP outpatients with usual prescribing (TAP: n = 58, OXN: n = 77) at a tertiary-care Spanish Hospital to compare health-related quality-of-life (HRQoL) records. Health utility was derived from the EQ-5D-3L. Regression models were performed to search for other HRQoL determinants. Pain intensity, relief, analgesic prescription, adverse events, inpatient stays, emergency department visits, and change to painkiller prescriptions were registered from electronic records. Results: Health utility (0.43 6 0.24 scores, from-0.654 to 1) was similar for both opioids, although TAP showed a signi ficantly low daily opioid dose requirement, neuromodulators use, and constipation side effect compared with OXN. After multivariable adjustment, the signi ficant predictors of impaired HRQoL were pain intensity ( 5 =-0.227, 95% CI-0-035 to-0.0 05), number of adverse events ( 5 =-0.201, 95% CI-0.024 to-0.004), and opioid daily dose ( 5 =-0.175, 95% CI-0.097 to-0.012). Male sex ( 5 = -0.044) and pain relief ( 5 = 0.158) should be taken into account for future studies. Conclusions: HRQoL was similar for TAP and OXN in real-world patients with CNCP, albeit with a TAP opioid-sparing effect. More work is needed to explore HRQoL determinants in relation to long-term opioid use in CNCP.
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| 18. |
- Santos-Pardo, Irene, et al.
(författare)
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Glycemic Control and Coronary Stent Failure in Patients With Type 2 Diabetes Mellitus
- 2024
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Ingår i: Journal of the American College of Cardiology. - : Elsevier. - 0735-1097 .- 1558-3597. ; 84:3, s. 260-272
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The impact of glycemic control in the risk of stent failure in subjects with type 2 diabetes (T2D) is currently unknown.OBJECTIVES: This study sought to study whether poor glycemic control is associated with a higher risk of stent failure in subjects with T2D.METHODS: This observational study included all patients in Sweden with T2D who underwent implantation of secondgeneration drug-eluting stents (DES) during 2010 to 2020. The exposure variable was the updated mean of glycated hemoglobin (HbA1c ). Individuals were strati fied by glycemic control, with HbA1c 6.1% to 7.0% (43-53 mmol/mol) as the reference group. The primary endpoint was the occurrence of stent failure (in-stent restenosis and stent thrombosis). The main result was analyzed in a complete cases model. Sensitivity analyses were performed for missing data and a model with death as a competing risk.RESULTS: The study population consisted of 52,457 individuals (70,453 DES). The number of complete cases was 24,411 (29,029 DES). The median follow-up was 6.4 years. The fully adjusted HR was 1.10 (95% CI: 0.80-1.52) for HbA1c of ≤ 5.5% (≤ 37 mmol/mol), 1.02 (95% CI: 0.85-1.23) for HbA1c of 5.6% to 6.0% (38-42 mmol/mol), 1.25 (95% CI: 1.11-1.41) for HbA1c of 7.1% to 8.0% (54-64 mmol/mol), 1.30 (95% CI: 1.13-1.51) for HbA1c of 8.1% to 9.0% (65-75 mmol/mol), 1.46 (95% CI: 1.21-1.76) for HbA1c of 9.1% to 10.0% (76-86 mmol/mol), and 1.33 (95% CI: 1.06-1.66) for HbA1c of ≥ 10.1% (≥ 87 mmol/ mol). Sensitivity analyses did not change the main result.CONCLUSIONS: We found a signi ficant association between poor glycemic control and a higher risk of stent failure driven by in-stent restenosis.
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| 19. |
- Santos-Pardo, Irene, et al.
(författare)
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Risk of stent failure in patients with diabetes treated with glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors : A nationwide observational study
- 2021
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Ingår i: International Journal of Cardiology. - : Elsevier. - 0167-5273 .- 1874-1754. ; 330, s. 23-29
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Tidskriftsartikel (refereegranskat)abstract
- Background: Incretins are a group of glucose-lowering drugs with favourable cardiovascular (CV) effects against neoatherosclerosis. Incretins' potential effect in stent failure is unknown. The aim of this study is to determine if incretin treatment decreases the risk of stent-thrombosis (ST), and/or in-stent restenosis (ISR) after percutaneous coronary intervention (PCI) with implanted drug-eluting stents (DES).Methods: Observational study including all diabetes patients who underwent PCI with DES in Sweden from 2007 to 2017. By merging 5 national registers, the information on patient characteristics, outcomes and drug dispenses was retrieved. Cox regression analysis with estimated hazard ratios (HRs) adjusted for confounders with 95% confidence intervals (Cis) was used to analyse for the occurrence of ST/ISR, and major adverse cardiovascular events (MACE). A subgroup analysis for the type of incretin treatment was performed.Results: In total 18,505 diabetes patients (30% women) underwent PCI, and 32,463 DES were implanted. Of those, 10% (3449 DES in 1943 patients) were treated with incretins. Median follow-up time was 995 clays (Control Group) vs. 771 days (Incretin Group). No significant difference in the risk of ST/ISR was found neither for the main study group (HR:0.98 95% CI:0.80-1.19) nor for the subgroups. No reduction of the risk of MACE (HR:0.96 95% CI:0.88-1.06) was observed. There was a 26% lower risk for CV death in favour of incretin treated patients (HR:0.74 95% 0:057-0.95).Conclusion: In diabetes patients who underwent PCI incretin treatment was not associated with lower risk of stent failure, but with lower risk of CV death.
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| 20. |
- Shumilova, Oleksandra, et al.
(författare)
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Simulating rewetting events in intermittent rivers and ephemeral streams : A global analysis of leached nutrients and organic matter
- 2019
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Ingår i: Global Change Biology. - : WILEY. - 1354-1013 .- 1365-2486. ; 25:5, s. 1591-1611
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Tidskriftsartikel (refereegranskat)abstract
- Climate change and human pressures are changing the global distribution and the extent of intermittent rivers and ephemeral streams (IRES), which comprise half of the global river network area. IRES are characterized by periods of flow cessation, during which channel substrates accumulate and undergo physico-chemical changes (preconditioning), and periods of flow resumption, when these substrates are rewetted and release pulses of dissolved nutrients and organic matter (OM). However, there are no estimates of the amounts and quality of leached substances, nor is there information on the underlying environmental constraints operating at the global scale. We experimentally simulated, under standard laboratory conditions, rewetting of leaves, riverbed sediments, and epilithic biofilms collected during the dry phase across 205 IRES from five major climate zones. We determined the amounts and qualitative characteristics of the leached nutrients and OM, and estimated their areal fluxes from riverbeds. In addition, we evaluated the variance in leachate characteristics in relation to selected environmental variables and substrate characteristics. We found that sediments, due to their large quantities within riverbeds, contribute most to the overall flux of dissolved substances during rewetting events (56%-98%), and that flux rates distinctly differ among climate zones. Dissolved organic carbon, phenolics, and nitrate contributed most to the areal fluxes. The largest amounts of leached substances were found in the continental climate zone, coinciding with the lowest potential bioavailability of the leached OM. The opposite pattern was found in the arid zone. Environmental variables expected to be modified under climate change (i.e. potential evapotranspiration, aridity, dry period duration, land use) were correlated with the amount of leached substances, with the strongest relationship found for sediments. These results show that the role of IRES should be accounted for in global biogeochemical cycles, especially because prevalence of IRES will increase due to increasing severity of drying events.
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