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Freshwaters commonly face human pressure, which produces multiple stressor scenarios that may threaten their ecological status. Biotic community assessments are useful tools to monitor such changes, and the European Water Framework Directive (WFD) has brought this into the legislative framework. The present study focused on a small mountain river facing multiple stresses, with the purpose of (1) evaluating the sensitivity of the macroinvertebrate community to the stresses, (2) assessing whether the ecological status was impaired in different years and (3) comparing the WFD approach with more refined community analyses. The river was generally in a very good ecological state. Despite seasonal and inter-annual fluctuations, no evident stressor-related effects were detected. We hypothesise that the observed resilience was the result of (1) the current dormant state of the abandoned mining areas (the most relevant potential source of contamination) and (2) the naturalness and strong current of the river, which buffered the impacts of contamination. Such a pattern may be generally valid for small mountain rivers, making them therefore more resilient to stresses. Nevertheless, small changes in community structure in the lowest reach of the river – undetected by the WFD assessment scheme – suggest that some disturbance was present, signalling the need for intervention by managers.

1. The Asian clam Corbicula fluminea is an invasive freshwater species that can cause adverse ecological and economic impacts. Information on its dispersal abilities, ecological preferences and impacts may contribute towards the improvement of management strategies, including those relating to regulatory demands such as the European Water Framework Directive (WFD).2. Both the above perspectives were addressed through inspection of environmental constraints to C. fluminea dispersal and impacts in a semi-natural drainage catchment (interconnected system of ditches). Forty sites were surveyed in 2014 to describe the species distribution and to characterize benthic macroinvertebrate communities, water column and sediment physico-chemistry, as well as the hydromorphological conditions. 3. Clams were unevenly distributed in the study area and artificial barriers (dikes) did not prevent downstream dispersal of juveniles. Large variation in clam density (0-3077 clams m −2 ) could not be explained by physico-chemical or hydromorphological gradients. Although typical clam preference ranges reported in the literature were often exceeded, dense populations were nevertheless observed. 4. Macroinvertebrate community structure suggested associations between the Asian clam and some functional feeding groups. However, the impacts of clams on macroinvertebrate assemblages and ecological quality were negligible, suggesting that contemporary methods designed to comply with the WFD bioassessment scheme may fail to detect important drivers of ecological change in freshwater ecosystems.5. This study demonstrated the reduced ecological impacts and broad ecological competence of the Asian clam, but also that its spread depends on human vectors. These findings highlight the need to rethink prediction tools supporting preventive measures against the introduction and spread of this invasive bivalve.

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Objective: This study aimed to establish age and gender-related normative values for the Balance Evaluation System Test (BES-Test), Mini-BESTest, Brief-BESTest, Timed Up and Go (TUG) test and Usual Gait Speed (UGS) for Portuguese healthy older people aged 60 to 89 years. Design: An exploratory cross-sectional study was conducted. Local: Portugal. Population: Portuguese healthy older people aged 60 to 89 years. Methods: Participants were recruited from the community. Socio-demographic, anthropometric and general clinical data were collected with a structured questionnaire based on the International Classification of Functioning, Disability and Health. Balance was assessed with the BESTest, Mini-BESTest and Brief-BESTest, mobility with the TUG and gait speed with the six meters UGS. Normative scores were reported by age decades (60-69; 70-79 and 80-89 years old) and gender. Results: One hundred and thirteen healthy older people (75.8±8.9 years; 70.5% female) participated in this study. Mean scores for the BESTest (86.5±15.