Effects of UV Radiation (a) on community structure - Antarctic diatom communities - common in streams and pools which develop on glaciers and in protected areas which experience some warm periods - average fluence (light intensity) to kill one diatom cell ranged from 681 to 25,338 J.m -2 in 9 species of diatoms examined - number of photoproducts induced by exposure to 2,500 J.m -2 ( Figure 6 ) - photoproducts are degradation products of pigments following photooxidative damage - even within one group of microorganisms (e.g. diatoms) - considerable variation in amount of damage caused by UV radiation (as indicated by # of photoproducts induced - note log scale) - elongated &euml;needle-shaped&iacute; pennate diatoms are more sensitive (i.e. produce more photoproducts) than circular rod-shaped centric diatoms - amount of initial damage by UV (measured as photoproducts induced) and survival - negatively correlated ( Figure 10 ) - using same species as given in Fig.
(streams and pools; develop; L:on glaciers and in protected areas) (photoproducts; induced; by exposure to 2,500 J.m -2) (photoproducts; induced; ) (- photoproducts; are; degradation products of pigments following photooxidative damage -) (circular rod-shaped centric diatoms - amount of initial damage by UV; measured; ) (protected areas; experience; some warm periods) (examined - number of photoproducts; produce; more photoproducts) (degradation products of pigments; following; photooxidative damage) (Effects of UV Radiation (a) on community structure - Antarctic diatom communities - common in streams and pools; to kill; one diatom cell ranged from 681 to 25,338 J.m -2 in 9 species of diatoms examined - number of photoproducts induced by exposure to 2,500 J.m -2 ( Figure 6 ) - photoproducts are degradation products of pigments following photooxidative damage - even within one group of microorganisms (e.g. diatoms) - considerable variation in amount of damage) (Figure 10; using; same species) (pennate diatoms; are; more sensitive (i.e. produce more photoproducts) than circular rod-shaped centric diatoms - amount of initial damage by UV) (damage; caused; by UV radiation (as indicated by # of photoproducts induced - note log scale)
streams and pools photoproducts photoproducts - photoproducts circular rod-shaped centric diatoms - amount of initial damage by UV protected areas examined - number of photoproducts degradation products of pigments Effects of UV Radiation (a) on community structure - Antarctic diatom communities - common in streams and pools Figure 10 pennate diatoms damage
develop induced induced are measured experience produce following to kill using are caused
L:on glaciers and in protected areas
by exposure to 2,500 J.m -2
degradation products of pigments following photooxidative damage -
some warm periods
more photoproducts
photooxidative damage
one diatom cell ranged from 681 to 25,338 J.m -2 in 9 species of diatoms examined - number of photoproducts induced by exposure to 2,500 J.m -2 ( Figure 6 ) - photoproducts are degradation products of pigments following photooxidative damage - even within one group of microorganisms (e.g. diatoms) - considerable variation in amount of damage
same species
more sensitive (i.e. produce more photoproducts) than circular rod-shaped centric diatoms - amount of initial damage by UV
by UV radiation (as indicated by # of photoproducts induced - note log scale