Evaluation of Water Framework Directive metrics to analyse trends in water quality in the Netherlands

A Preliminary Analysis of Anthropogenic and Natural Impacts on a Volcanic Lake Ecosystem in Southern Italy by UAV-Based Monitoring

Lakes play an important role in providing various ecosystem services. However, stressors such as climate change, land use, or land-cover change threaten the ecological functions of lakes. National and international legislations address these threats and establish consistent, long-term monitoring schemes. Remote sensing techniques based on the use of Unmanned Aerial Vehicles (UAV) have recently been demonstrated to provide accurate and low-cost spatio-temporal views for the assessment of the ecological status of aquatic ecosystems and the identification of areas at risk of contamination. Few studies have been carried out so far on the employment of these tools in the monitoring of lakes. Therefore, high-resolution UAV surveys were used to analyse and evaluate natural and anthropogenic impacts on the habitat status of a volcanic lake in a protected area. Five UAV flights took place during a year-long cycle (November 2020 to November 2021) in a volcanic lake located in southern Italy. For each flight performance, an orthomosaic of georeferenced RGB images was obtained, and the different features of interest were monitored and quantified using automated processing in a GIS environment. The UAV images made it possible not only to estimate the flooded shores but also to detect the impact of human-made structures and infrastructures on the lagoon environment. It has been possible to observe how the rapid changes in lake-water level have led to the submersion of about 90.000 m² of terrain in winter, causing the fragmentation and degradation of habitats, while the connectivity of the natural ecosystem has been threatened by the presence of the road around the lake. The proposed methodology is rather simple and easily replicable by decision makers and local administrators and can be useful for choosing the best restoration interventions.

Disparate Environmental Monitoring as a Barrier to the Availability and Accessibility of Open Access Data on the Tidal Thames

Open Access data plays an increasingly important role in discussions of environmental issues. Limited availability or poor quality data can impede citizen participation in environmental dialogue, leading to their voices being undermined. This study assesses the quality of Open Access environmental data and barriers to its accessibility in the Thames Estuary. Data quality is assessed by its ability to track long-term trends in temperature, salinity, turbidity, and dissolved oxygen. The inconsistencies found in the data required analyses and careful interpretation beyond what would be expected of a citizen. The lack of clear documentation and centralized database acted as a major barrier to usability. A set of recommendations are produced for estuarine monitoring, including defining minimum standards for metadata, creating a centralized database for better quality control and accessibility, and developing flexible monitoring protocols that can incorporate new hypotheses and partnerships. The goal of the recommendations is to create monitoring which can encourage better science and wider participation in the natural environment.

Has Water Quality Improved or Been Maintained? A Quantitative Assessment Procedure

Many policies require reporting on water quality trends. This is usually addressed by testing a hypothesis positing that there was zero slope in some parameter of the sampled population over a given period. Failure to achieve "statistical significance" is often falsely interpreted as evidence that there was no trend of concern-the -value of these tests can become ever smaller as the sample size increases and so also can the detectable trend. To avoid this problem, a new trend direction assessment (TDA) procedure is proposed, based on a formulation in psychological literature that considers error risks when inferring the direction of differences between two population means. The TDA procedure abandons testing altogether and instead calculates probabilities that water quality variables have been increasing or decreasing. Nominated probability breakpoints then give rise to a graduated scale in which phrases such as "extremely likely" or "unlikely" can be used to summarize results, avoiding casting many into a "not statistically significant" box. This trend assessment procedure requires no more information than a traditional test, for which the significance level is reinterpreted as a misclassification error rate (inferring an increase when in fact there was a decrease, or vice versa). Example applications of this procedure to small and large datasets are given. This procedure also possesses a possible framework that addresses the more complex question of whether water quality has been "maintained," in which a trend magnitude of environmental significance must be defined. The TDA procedure may be applied to any environment, not just water quality.