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

Abbreviations: T, temperature (average water column); UVB300–318, ultraviolet B radiation measured in the 300–318 nm range (2 nm of interval); UVA320–398, ultraviolet A radiation measured in the 320–398 nm range (2 nm of interval); TP, total phosphorus; TDP, total dissolved phosphorus. *UV radiation data were measured at noon using a LI-8000 spectroradiometer (LI-COR, Lincoln, NE, USA). Diffuse attenuation coefficients for downward irradiance (Kd) 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.