Koski, V., & Eidsvik, J. (2024). Sampling design methods for making improved lake management decisions. Environmetrics, e2842. https://doi.org/10.1002/env.2842

 

 

Finland’s thousands of lakes are extremely important for economic, environmental, and recreational activities. The ecological status of Finnish lakes is mostly good, but the status is particularly weakened by eutrophication (accumulation of nutrients leading to excessive growth of microorganisms and oxygen depletion). If the status of a lake is weak, then the Water Framework Directive of the European Union obligates to implement management alternatives. Because there is uncertainty associated with the status of lakes, additional data would help policy makers in the difficult decisions about the costly management alternatives. Using statistical techniques, the value and usefulness of additional lake monitoring data can be assessed before they are actually collected. With reasonable ecological values and management costs, the value of this information can be compared with the costs of monitoring, and data are worth gathering if the expected value of information exceeds the monitoring costs. The aim of this study is to determine where and how much data should be collected, so that the resources invested in monitoring are wisely spent. The results imply that monitoring is worth implementing to make better management decisions. Results further show that good monitoring designs are consisting of lakes whose status is difficult to determine a priori. Statistical designs clearly outperform simpler designs based on for instance lake size, amount of agricultural land, or geographical spread in the monitoring design.