Biological weighting function, BWF

Figure 7. Biologically effective exposure (BEE) for mortality in the cladoceran Daphnia pulicaria as estimated from a 7 h solar phototron exposure experiment. BEE is estimated by multiplying the biological weighting function (BWF, an estimate of the wavelength-specific effects of UV), times the cumulative solar energy spectrum (here a 7 h exposure period during midday). [Modified from [59], with permission.]...

If DAS reduces the problem to the monochromatic situation, the other approach proposed by Rundel is a deconvolution technique in which it is assumed that the action spectrum [which, in this case, can be defined as the biological weighting function (BWF) ] is an analytical continuous function e( ), and the predicted system response R to the ith irradiation regime E iX, t) can be expressed as a function, F, of the biologically active irradiance integrated over the irradiation time ... 

Figure 6. Effects of UVR on photosynthesis (total C assimilation) of phytoplankton moved through different mixing depths, presented as per cent photosynthesis in quartz (UVR transparent) relative to glass (partial UVR exclusion) bottles. Measured rates are for bottles that were circulated over the indicated depth ranges at the rate of once per 4 min (0-2 m), once per 8 min (0-3.9 m) and once per 20 min (0-10 and 0-14 m) for a 4 h midday incubation period. The modeled rates are the average of the steady-state (irradiance based) photosynthesis predicted using a biological weighting function and photosynthesis irradiance (BWF/P-I) curve applied to in situ irradiance estimated from recorded surface irradiance, depth of the bottles and measured vertical extinction coefficient. Model and measurements agree within measurement variability (ca. 10%) except for the 0-10 m incubation. Experiments were conducted in Lake Lucerne on September 13,1999 (no asterisks) and September 15,1999 (asterisks, see exposure data in Figure 2). [Modified from Kohler et al. 79.]...

BEE, biologically effective exposure BEI, biologically effective irradiance BLP, biologically-available photoproduct BWF, biological weighting function... 

---