Physical, chemical, and biological variables measured under initial experimental conditions.

<p>Abbreviations: T, temperature (average water column); UVB_300–318, ultraviolet B radiation measured in the 300–318 nm range (2 nm of interval); UVA_320–398, ultraviolet A radiation measured in the 320–398 nm range (2 nm of interval); TP, total phosphorus; TDP, total dissolved phosphorus.</p>*<p>UV radiation data were measured at noon using a LI-8000 spectroradiometer (LI-COR, Lincoln, NE, USA). Diffuse attenuation coefficients for downward irradiance (K_d) were determined from the slope of the linear regression of the natural logarithm of downwelling irradiance vs. depth for each region of the solar-radiation spectrum.