Fig. 5
Concentration (log-transformed) of small, medium, and large copepods across 10 cm depth bins in relation to calculated illuminance (lx) from day to night (panel a; N = 35,070 samples per graph). Panels b and c show predicted concentrations in relation to temperature (°C) and chlorophyll-a (µg l−1), respectively, under dark conditions (illuminance < 0.001 lx) or light conditions (illuminance 0.01–0.06 lx) at night, including nautical and astronomical twilight (N = 27,054 depth bins sampled). Light is shown categorically for illustration, but was included as a continuous variable in the statistical models. Trend lines indicate model-predicted effects, with ribbons representing standard errors. Data were collected in Lake Stechlin, Germany, across two lunar cycles. Light is separated categorically for illustration purposes but was included as a continuous variable in the statistical models. Trend lines shows the model-predicted effects, ribbons shows the standard error of this estimate.
