Size metrics Clause Samples

Size metrics. Choice of size metrics was based on a study in 78 German lakes (▇▇▇▇▇▇▇ et al., 2011, see part 1 of this report). For all European lakes included, we calculated geometric mean length (cm), variance of the length data, skewness and kurtosis of the length-frequency distribution, number of size classes, maximum length (cm), interquartile range (cm), length at the 95th percentile (cm) and size diversity. Size diversity (▇▇▇▇▇▇▇▇ et al., 2008) combines several aspects of other size metrics into a single comparable value and was tested to be sensitive to a broad range of lake descriptors at the regional scale (▇▇▇▇▇▇▇ et al., 2011). For fish- length data, size diversity is high when the catch consists of many different size classes (single size classes can still dominate the catch) or if the abundances between the size classes are relatively equal (▇▇▇▇▇▇▇ et al., 2011). For details of all other size metrics see ▇▇▇▇▇▇▇ et al. (2011). Size metrics related to fish weight could not be calculated for the European dataset, because of missing FW data in 61% of the lakes. Additionally, we did not include normalised length spectra, as for almost one third of the lakes the R2 of the linear regression models was < 0.5.