Summary Climate change scenarios predict an increase in global temperature and alterations in precipitation regimes, which may change nutrient concentrations in waterbodies. In forested streams, decomposition of allochthonous organic matter is a key ecosystem process that is affected by the quality of plant litter entering the streams and several environmental factors, including nutrient concentrations, whose interactive effects are difficult to predict. We examined the concomitant effects of increased temperature, concentration of inorganic nutrients in stream water and litter quality on leaf decomposition and activity of microbial decomposers. Leaves of alder (Alnus glutinosa) and oak (Quercus robur), representative of high and low initial N content, respectively, were immersed in a stream (NW Portugal) to allow microbial colonisation and then were exposed in microcosms to increasing concentrations of N‐NO3 (0.09–5 mg L−1; six levels) and P‐PO4 (0.003–0.3 mg L−1; three levels) alone or in all possible combinations. One set of microcosms was kept at 12 °C, a temperature typically found in Iberian streams in autumn, and the other set at 18 °C to simulate a warming scenario. Nitrogen immobilisation was higher in alder than in oak leaves, and increased with temperature and N concentration in stream water for both leaf species. Leaf decomposition, fungal biomass accrual and reproduction were not affected by P concentration, but overall microbial activity increased asymptotically (Michaelis–Menten kinetics) with N concentration. Increased temperature led to an increase in maximum activity of fungal decomposers and to a decrease in N concentration needed to achieve it, especially in alder leaves. Under the predicted warming scenario, leaf decomposition may become faster in streams with lower nutrient levels, especially those receiving high‐quality leaf litter.

Summary 1. We investigated the effects of riparian plant diversity (species number and identity) and temperature on microbially mediated leaf decomposition by assessing fungal biodiversity, fungal reproduction and leaf mass loss. 2. Leaves of five riparian plant species were first immersed in a stream to allow microbial colonisation and were then exposed, alone or in all possible combinations, at 16 or 24 °C in laboratory microcosms. 3. Fungal biodiversity was reduced by temperature but was not affected by litter diversity. Temperature altered fungal community composition with species of warmer climate, such as Lunulospora curvula, becoming dominant. 4. Fungal reproduction was affected by litter diversity, but not by temperature. Fungal reproduction in leaf mixtures did not differ or was lower than that expected from the weighted sum of fungal sporulation on individual leaf species. At the higher temperature, the negative effect of litter diversity on fungal reproduction decreased with the number of leaf species. 5. Leaf mass loss was affected by the identity of leaf mixtures (i.e. litter quality), but not by leaf species number. This was mainly explained by the negative correlation between leaf decomposition and initial lignin concentration of leaves. 6. At 24 °C, the negative effects of lignin on microbially mediated leaf decomposition diminished, suggesting that higher temperatures may weaken the effects of litter quality on plant litter decomposition in streams. 7. The reduction in the negative effects of lignin at the higher temperature resulted in an increased microbially mediated litter decomposition, which may favour invertebrate‐mediated litter decomposition leading to a depletion of litter stocks in streams.

Studies investigating the impacts of biodiversity loss on ecosystem processes have often reached different conclusions, probably because insufficient attention has been paid to some aspects including (1) which biodiversity measure (e.g., species number, species identity or trait) better explains ecosystem functioning, (2) the mechanisms underpinning biodiversity effects, and (3) how can environmental context modulates biodiversity effects. Here, we investigated how species number (one to three species) and traits of aquatic fungal decomposers (by replacement of a functional type from an unpolluted site by another from a metal-polluted site) affect fungal production (biomass accumulation) and plant litter decomposition in the presence and absence of metal stress. To examine the putative mechanisms that explain biodiversity effects, we determined the contribution of each fungal species to the total biomass produced in multicultures by real-time PCR. In the absence of metal, positive diversity effects were observed for fungal production and leaf decomposition as a result of species complementarity. Metal stress decreased diversity effects on leaf decomposition in assemblages containing the functional type from the unpolluted site, probably due to competitive interactions between fungi. However, dominance effect maintained positive diversity effects under metal stress in assemblages containing the functional type from the metal-polluted site. These findings emphasize the importance of intraspecific diversity in modulating diversity effects under metal stress, providing evidence that trait-based diversity measures should be incorporated when examining biodiversity effects.

The presence of age-related comorbidities prone elderly patients to the phenomenon of polypharmacy and consequently to a higher risk of nonadherence. Thus, this paper aims to characterize the medication consumption profile and explore the relationship of beliefs and daily medication management on medication adherence by home-dwelling polymedicated elderly people. A questionnaire on adherence, managing, and beliefs of medicines was applied to polymedicated patients with ≥65 years old, in primary care centers of the central region of Portugal. Of the 1089 participants, 47.7% were considered nonadherent. Forgetfulness (38.8%), difficulties in managing medication (14.3%), concerns with side effects (10.7%), and the price of medication (9.2%) were pointed as relevant medication nonadherence-related factors. It was observed that patients who had difficulties managing medicines, common forgetfulness, concerns with side effects, doubting the need for the medication, considered prices expensive, and had a lack of trust for some medicines had a higher risk of being nonadherent. This study provides relevant information concerning the daily routine and management of medicines that can be useful to the development of educational strategies to promote health literacy and improve medication adherence in polymedicated home-dwelling elderly.

Increases of extreme weather events are predicted to occur with ongoing climate change, but impacts to freshwaters have rarely been examined. We assessed the effects of temperature on leaf-litter associated fungi by exposing leaves colonized in a stream to 18 °C (control), 25 °C, or 18 °C after freezing. Treatments altered fungal dominance on leaves; Lunulospora curvula sporulation was stimulated by increased temperature and stopped by the freeze-thaw treatment. Fungal biomass and diversity decreased at 18 °C after freezing, but not at 25 °C. Leaf decomposition was retarded by the freeze-thaw treatment (k = -0.024 day -1 ) and stimulated at 25 °C (k = -0.069 day -1 ). Results suggest that occasional freezing may constrain fungal diversity and their ecological functions, while warming appears to accelerate plant-litter decomposition in streams.