... T.M., Pancotto, V .A. , Flint, S.D., Ballare, C.L., Sala, O.E., Scopel, A. L., and Caldwell, M.M.,Six years of solar UV-B manipulations affect growth of Sphagnum and vascular plants in a Tierra DelFuego ... UV-B radi-ation occur at higher elevations (increasing by approximately 20% for each 100 0 m), placing alpineand subalpine ecosystems at considerable risk (Blumthaler and Ambach 1990, Sommaruga ... exposure of aquatic organisms to UV-B. Kellyet al. (2003) manipulated UV -A and UV-B levels in streams with varying amounts of riparianvegetation. Chlorophyll a biomass and C accrual were lower...