0000000000681811
AUTHOR
Olli Malve
Macrosystem community change in lake phytoplankton and its implications for diversity and function
Aim We use lake phytoplankton community data to quantify the spatio-temporal and scale-dependent impacts of eutrophication, land-use and climate change on species niches and community assembly processes while accounting for species traits and phylogenetic constraints. Location Finland. Time period 1977–2017. Major taxa Phytoplankton. Methods We use hierarchical modelling of species communities (HMSC) to model metacommunity trajectories at 853 lakes over four decades of environmental change, including a hierarchical spatial structure to account for scale-dependent processes. Using a “region of common profile” approach, we evaluate compositional changes of species communities and trait profil…
Lake Load Response (LLR) – mallityökalu vesialueiden hoidon suunnittelun apuvälineenä
For eutrophic lakes, achieving good water quality usually requires a reduction in external loading. The Lake Load Response (LLR) tool, based on the LakeState (LS) model, can be used to predict the necessary loading reduction, which can be utilized when making decisions on the management of the lake. The best predictions are made when the input values of the incoming loading, water outflow and in-lake total phosphorus, total nitrogen and chlorophyll a concentrations are as accurate as possible. Accurate loading data is often hard to collect because of the lack of resources for observations. However, LLR-runs made for the lake Lehesjärvi-Vähäjärvi in Jyväskylä showed that examining the needed…
A practical approach to improve the statistical performance of surface water monitoring networks
The representativeness of aquatic ecosystem monitoring and the precision of the assessment results are of high importance when implementing the EU’s Water Framework Directive that aims to secure a good status of waterbodies in Europe. However, adapting monitoring designs to answer the objectives and allocating the sampling resources effectively are seldom practiced. Here, we present a practical solution how the sampling effort could be re-allocated without decreasing the precision and confidence of status class assignment. For demonstrating this, we used a large data set of 272 intensively monitored Finnish lake, coastal, and river waterbodies utilizing an existing framework for quantifying…