Stratosphene atmospit Stratosphere absone ozone layer is thinning however From the 1950s through the 1990s chlorofluorocarbons CFCs were used as propellants in spray cans and coolants in refrigerators They were also used in the manufacture of plastics In the 1970s scientists discovered that CFCs decomposed by UVR were destroying the ozone layer In 1985 a springtime depletion of stratospheric ozone was discovered over the South Pole This is often referred to as the Antarctic ozone hole In 1987 27 countries signed a global environmental agreement called the Montr al Protocol to Reduce Substances that Deplete the Ozone Layer Its London Amendment 1990 called for the production of CFCs to end by 2000 The production of CFCs has been banned in many Effects of UVR on Different Organisms Type of organism algae or phytoplankton plants bacteria protozoa zooplankton fish amphibians Overall effect of increasing amounts of UVR can inhibit photosynthesis in general inhibits photosynthesis reduces leaf size and decreases growth of many plants depending on species may be killed or highly resistant can be damaging or kill depending on age and other factors damaging can kill fish causes developmental damage answer the Analysis questions Analysis 1 What might be the effects of increasing amounts of UVR on productivity 2 What direct effects does increasing UVR have on animals 3 What indirect effects might increasing UVR have on animals Adaptations for protection against UVR UVR absorbing compounds 4 Suggest an approach to counteract increased levels of UVR in ecosystems What would you need to find out to ensure that your approach is a wise one pigmentation UVR absorbing compounds DNA repair processes DNA repair processes varies damages cells in some species DNA repair processes in some protozoa pigmentation UVR absorbing compounds DNA repair pigmentation DNA repair in fish eggs pigmentation Environmental features that protect against UVR dissolved material in water can act as a shield shade can protect plants protozoa living in deeper waters are shielded from UVR amount of Sun exposure is limited zooplankton are shielded from UVR when they swim to deeper waters deeper cooler waters protect developing fish dissolved materials in water can Machield