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SummaryBacteria are major drivers of biogeochemical nutrient cycles and energy fluxes in marine environments, yet how bacterial communities respond to environmental change is not well known. Metagenomes allow examination of genetic responses of the entire microbial community to environmental change. However, it is challenging to link metagenomes directly to biogeochemical process rates. Here, we investigate metagenomic responses in natural bacterioplankton communities to simulated environmental stressors in the Baltic Sea, including increased river water input, increased nutrient concentration, and reduced oxygen level. This allowed us to identify informative prokaryotic gene markers, responding to environmental perturbation. Our results demonstrate that metagenomic and metabolic changes in bacterial communities in response to environmental stressors are influenced both by the initial community composition and by the biogeochemical factors shaping the functional response. Furthermore, the different sources of dissolved organic matter (DOM) had the largest impact on metagenomic blueprint. Most prominently, changes in DOM loads influenced specific transporter types reflecting the substrate availability and DOC assimilation and consumption pathways. The results provide new knowledge for developing models of ecosystem structure and biogeochemical cycling in future climate change scenarios and advance our exploration of the potential use of marine microorganisms as markers for environmental conditions.

AbstractThis assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595–828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.

Abstract The magnitude and frequency of marine heatwaves are increasing and predicted to intensify, but our ability to understand the real‐world effects on vital benthic ecosystems is lagging behind. Prior insights into the impacts of marine heatwaves are often derived from observational or laboratory studies. Observational studies may not fully disentangle the complexities of potential compound events and typically focus on severe, often lethal marine heatwaves. Laboratory studies, on the contrary, while valuable for understanding specific mechanisms, often use artificial setups and can introduce unnatural disturbances that do not reflect real‐world scenarios. To investigate sublethal temperature effects of marine heatwaves in a natural benthic habitat, we developed a novel approach for inducing elevated water temperatures in situ over several days. The system utilizes domestic underfloor heating technology combined with custom‐made benthic chambers. We placed 10 chambers for 15 days in a bare‐sediment habitat at 2.5 m depth and heated five chambers to 5°C above ambient water temperatures in summer for 6 days, followed by a period of 7 days at ambient temperatures. Incubations during day and night were performed during the experiment to assess changes in ecosystem functioning (solute fluxes) and sediment cores were collected at the end of the experiment to assess the effects of a realistic marine heatwave on benthic community structure. The results indicate that while the benthic community structure remained similar between the treatments, except for a size shift of Marenzelleria spp. towards smaller individuals in the heated treatment, elevated temperatures caused a significant increase in community respiration and amplified the magnitude of either efflux or influx of nutrients (NH4+‐N, PO43−‐P and Si). Primary production during daytime incubations remained mostly unaffected by the heatwave treatment, contributing to the concept of heterotrophy being more influenced by increased temperatures than autotrophy. This study confirms the suitability of the novel system for examining the impact of temperature on benthic habitats in situ and demonstrates its potential for the investigation of complex habitats and communities, which are essential for our understanding of the ecosystem‐level effects of climate change. Read the free Plain Language Summary for this article on the Journal blog.

Wetlands are a critical part of natural environments that offer a wide range of ecosystem services. In urban areas, wetlands contribute to the livability of cities through improving the water quality, carbon sequestration, providing habitats for wildlife species, reducing the effects of urban heat islands, and creating recreation opportunities. However, maintaining wetlands in urban areas faces many challenges, such as the reduction of hydrological functions, changed water regimes due to barriers, contamination by wastewater, habitat loss due to land-use change, and loss of biodiversity due to the entry of alien species. In this article, we review the theoretical background of wetlands in urban areas through the existing studies in the literature. We provide knowledge on urban wetlands and highlight the benefits of these wetlands in urban areas. These benefits include sustainability, biodiversity, urban heat islands, social perception, and recreation values. We also summarize the objectives, methodologies, and findings of the reviewed articles in five tables. In addition, we summarize the critical research gaps addressed in the reviewed articles. Our review study addresses the research gaps by performing a rigorous analysis to identify significant open research challenges, showing the path toward future research in the field. We further discuss and highlight the role of policymakers and stakeholders in preserving wetlands and finally present our conclusions.

The most PCMs with high energy storage density have an unacceptably low heat conductivity and hence internal heat transfer enhancement techniques such as fins or other metal structures are required in latent heat thermal storage (LHTS) applications. Previous work has concentrated on numerical and experimental examination in determining the influence of the fins in melting phase change material. This paper presents a simplified analytical model based on a quasi-linear, transient, thin-fin equation which predicts the solid–liquid interface location and temperature distribution of the fin in the melting process with a constant imposed end-wall temperature. The analytical results are compared to the numerical results and they show good agreement. Due to the assumptions made in the model, the speed of the solid–liquid interface during the melting process is slightly too slow.

Ethanol (88-880 mmol/l) inhibited the formation of proaggregatory, vasoconstricting thromboxane A2 (TxA2) during whole blood clotting and during thrombin-induced aggregation of platelet rich plasma. This inhibition was counteracted by the addition of exogenous arachidonic acid, which suggested that ethanol suppressed the liberation of arachidonic acid, evidently by inhibiting phospholipase A2. Ethanol had no effect on the formation of prostacyclin (PGI2, epoprostenol), the endogenous antagonist of TxA2, by human lung. Thus our results suggest that ethanol may shift the balance between TxA2 and PGI2 to the dominance of antiaggregatory, vasodilating PGI2 by suppressing the release of arachidonic acid in platelets. This finding might partly explain why ethanol protects against atherosclerosis and also the increased risk of subarachnoidal haemorrhage after heavy ethanol intake.

The effect of alcohol (1.2 and 2.0 g/kg) on the urinary testosterone-to-epitestosterone (T/E) ratio was studied by two experiments each conducted with four healthy females and males. The intake of 2.0 g/kg of ethanol within 5 h in the evening significantly increased plasma testosterone concentration and ratio of T/E in urine collected next morning in females. The results suggest that alcohol increases the T/E ratio more in females than in males. The effect of high doses of alcohol on urinary T/E ratio must be kept in mind when doping tests are performed during training periods.