Brief description of case studies Sample Clauses

Brief description of case studies. The report is structured around selected case studies, manly involving the analysis of existing datasets collected within Wiser. The case studies come from different European lake types in the Northern, Central, Alpine and Mediterranean regions and offer different angles and approaches to quantify the spatial and temporal variations of invertebrates. Xxxxx Xxxxxxx and coworkers focus on the variability of different invertebrate metrics looking at a very long time series of data coming from the shallow lake Naardermeer. Time-for-space analysis is used to disentagle the unexplained variation caused by replicate samples, sample processing, natural temporal variation and stochastic events in the data series of 23 years of macroinvertebrate data and abiotic variables. Xxxxxxxxx Xxxxxxx and Xxxxxx Xxxxxxxx use the variance partitioning approach in order to quantify the combined impact of eutophication and morphological pressures on the invertebrate assemblages inhabiting different lake zones of 57 Alpine lakes. This method allows to disentangle the problem of interactions among different groups of explaining factors including variables connected to the pure spatial pattern and to lake morphology and geology By including those sets of variables in the variance partitioning analysis the authors could isolate the pure effects of eutrophication and morphological pressures from the effects due to interactions with the other tested variables. Despite the great importance of those water bodies in areas of water scarcity, data from Mediterranean natural lakes are particularly scarce. For this reason, Xxxxxxxx Xxxxxxxx and coworkers look at the response to eutrophication of qualitative metrics (e.g. those based on presence – absence data) in different zones of lakes belonging to the volcanic district of Italy. A list of several taxa is proposed as tolerant and sensitive to euthrophication stressors that might be used in the development of the complete WFD compliant classification system. Xxxxxx XxXxxx and Xxxxxxx Xxxxxx apply a multivariate method in order to partition the variance of littoral invertebrates between riparian related habitat variables, littoral substrate variables and trophic status of Swedish lakes. They also look at the impact of large scale land use patterns, investigating whether invertebrate communities in impaired and natural lakes differ in their response to local habitat and nutrient descriptors, and how the different environmental descriptors affe...