Cover -- Half-title -- Series-title -- Title -- Copyright -- Contents -- Contributors -- Preface -- 1 Enhanced UV radiation - a new problem for the marine environment -- 1.1 Introduction -- 1.2 The solar spectrum and the nature of light -- 1.3 Attenuation of solar energy -- 1.3.1 Attenuation in the atmosphere -- 1.3.1.1 Absorbance of UV and the ozone cycle -- 1.3.1.2 Effects on UV intensity and UV/PAR ratios -- 1.3.1.3 Effects of clouds and particles -- 1.3.1.4 Season and latitude -- 1.3.2 Attenuation in the water column -- 1.3.2.1 Surface reflection -- 1.3.2.2 Scattering and absorption -- 1.4 Effect of light on biomolecules and processes -- 1.4.1 Bond energies -- 1.4.2 Production of radicals -- 1.4.3 UV in photosynthesis -- 1.4.4 UV in biogeochemical cycles -- 1.5 Summary -- References -- 2 UV physics and optics -- 2.1 Atmospheric UV radiation -- 2.1.1 Direct and diffuse UV radiation -- 2.1.2 Natural variability -- 2.1.3 Atmospheric UV instrumentation -- 2.1.4 Ozone -- 2.1.4.1 Natural variability -- 2.1.4.2 Ozone depletion -- 2.1.4.3 Impact of ozone depletion in surface irradiances -- 2.1.5 Artificial sources of UV -- 2.2 Hydrologic optics -- 2.2.1 Underwater light and UV penetration -- 2.2.2 Models -- 2.2.3 Underwater UV instrumentation -- 2.2.4 Measurements -- Acknowledgements -- References -- 3 Spectral weighting functions for quantifying effects of UV radiation in marine ecosystems -- 3.1 Introduction -- 3.2 Action spectra -- 3.3 Biological weighting functions -- 3.4 Relating response to exposure -- 3.4.1 Kinetics of UV damage -- 3.4.2 Kinetics of UV damage and recovery -- 3.5 Marine biological weighting functions -- 3.6 Biological weighting function methodology -- 3.6.1 Experimental considerations -- 3.6.2 Analytical considerations -- 3.7 Comprehensive models of UV effects -- 3.8 Predicting the effects of ozone depletion -- 3.9 Summary.

Acknowledgements -- References -- 4 Marine photochemistry and its impact on carbon cycling -- 4.1 Introduction -- 4.2 Photochemistry of dissolved organic matter -- 4.3 Impact of photochemical reactions on marine processes -- 4.4 Impact of photochemistry on oceanic carbon cycling -- 4.5 Summary -- Acknowledgements -- References -- 5 Photochemical production of biological substrates -- 5.1 Introduction -- 5.2 Photochemical sources of biological substrates -- 5.3 Summary -- Acknowledgements -- References -- 6 Mechanisms of UV damage to aquatic organisms -- 6.1 Introduction -- 6.2 Direct effects -- 6.2.1 Genetic damage -- 6.2.2 Protein damage -- 6.2.3 Photosynthesis -- 6.2.4 Carbon allocation -- 6.2.5 Pigment damage -- 6.2.6 Respiration -- 6.2.7 Nutrient uptake -- 6.2.8 Nitrogen fixation -- 6.2.9 Cell motility -- 6.2.10 Other effects -- 6.3 Indirect effects -- 6.3.1 Hydrogen peroxide and hydroxyl radicals -- 6.3.2 Superoxide radicals -- 6.3.3 Membrane lipid peroxidation -- 6.3.4 Singlet oxygen and other photochemical reactions -- 6.4 General issues -- 6.4.1 Variability in response -- 6.4.2 Evaluating the literature -- Acknowledgements -- References -- 7 Strategies for the minimisation of UV-induced damage -- 7.1 Introduction -- 7.2 UV avoidance mechanisms -- 7.3 Reduction of effective UV radiation -- 7.3.1 Extracellular screening agents -- 7.3.2 Intracellular screening agents -- 7.3.2.1 Mycosporine-like amino acids -- 7.3.2.2 Other intracellular screening agents -- 7.3.3 Behaviourally mediated UV screening -- 7.4 Repair of UV-induced damages -- 7.4.1 DNA repair -- 7.4.1.1 Photoreactivation -- 7.4.1.2 Nucleotide excision repair -- 7.4.1.3 Other mechanisms of DNA repair -- 7.4.2 Protein repair -- 7.4.3 Defences against forms of reactive oxygen -- 7.4.3.1 Antioxidant enzymes -- 7.4.3.2 Carotenoids -- 7.4.3.3 Other antioxidants.

7.5 Acclimation to changes in the UV light field -- 7.5.1 Physiological acclimation -- 7.5.2 Community changes -- 7.6 Summary and perspectives -- Acknowledgements -- References -- 8 UV radiation effects on heterotrophic bacterioplankton and viruses in marine ecosystems -- 8.1 Introduction -- 8.2 Early studies -- 8.3 Solar UVR effects on bacterioplankton production -- 8.4 UVR effects on microbial biogeochemical cycles -- 8.5 Effects of UVR on nucleic acids -- 8.6 DNA damage repair -- 8.7 Influence of UV radiation on viruses - destruction rates of particles and infectivity -- 8.8 Virus repair processes -- 8.9 DNA damage in the natural viral community -- 8.10 Induction of lysogens by UV radiation in marine systems -- 8.11 Summary -- Acknowledgements -- References -- 9 Effects of UV radiation on the physiology and ecology of marine phytoplankton -- 9.1 Introduction -- 9.2 Effects of UV radiation on phytoplankton processes -- 9.2.1 Primary production -- 9.2.1.1 Carbon uptake -- 9.2.1.2 Pigmentation -- 9.2.1.3 Modelling -- 9.2.2 Nutrient metabolism -- 9.2.3 Respiration -- 9.2.4 Organic matter excretion -- 9.2.5 Swimming and vertical migration -- 9.2.6 Specific growth rate -- 9.2.7 Cell size -- 9.2.8 Community composition -- 9.3 Ecological considerations -- 9.3.1 Photosynthetically active and UV radiation -- 9.3.2 Mixing in the upper water column -- 9.3.3 Spatial and temporal scales -- 9.4 Summary -- Acknowledgements -- References -- Note added in proof -- 10 Impact of solar UV radiation on zooplankton and fish -- 10.1 Introduction -- 10.2 Effects and responses to UV radiation in zooplankton and fish -- 10.2.1 Damaging effects -- 10.2.2 Recovery from UV radiation damage -- 10.2.3 Wavelength dependence of damage and repair -- 10.2.4 Reciprocity with and without repair mechanisms -- 10.2.5 Indirect effects -- 10.2.6 Photoprotective compounds.

10.2.7 UV radiation vulnerability in relation to habitat -- 10.2.8 UV detection -- 10.3 The pelagic environment -- 10.3.1 The structure of pelagic habitats -- 10.3.2 UV radiation attenuation and water mixing -- 10.4 Diel patterns of vertical distribution -- 10.5 Statistical issues -- 10.6 Concluding remarks -- Acknowledgements -- References -- 11 Implications of UV radiation for the food web structure and consequences on the carbon flow -- 11.1 Introduction -- 11.2 UV radiation and biological systems -- 11.3 Herbivorous versus microbial food web: implication of the UV-B radiation -- 11.4 UV-B and the carbon flux -- Acknowledgements -- References -- Index.