Elevated UV-B radiation did not affect decomposition rates of needles of two coniferous species in subtropical China

The increased level of ultraviolet-B (UV-B) radiation reaching the earth’s surface has profound implications for altering terrestrial ecosystem processes such as litter decomposition and nutrient cycling. Here we report on a field experiment that investigated the direct effect of elevated UV-B radiation on the rate of decomposition, lignin degradation, and N and P release from needle litter of two native coniferous species, Cunninghamia lanceolata and Pinus massoniana, in humid subtropical China. Elevated UV-B irradiation did not significantly accelerate litter mass loss and lignin photodegradation of the two species. Elevated UV-B irradiation accelerated the release of N and P from the litter of C. lanceolata, but not from that of P. massoniana. Our data indicated that elevated UV-B irradiation would accelerate N and P turnover in C. lanceolata forest. Our findings will contribute to the better understanding of the role of UV-B radiation in moist subtropical region.

► Investigated effect of UV-B radiation on needles decomposition in humid subtropical China. ► UV-B slightly accelerated litter mass loss of Cunninghamia Lanceolata and Pinus massoniana. ► UV-B accelerated the release of N and P from C. Lanceolata but not from P. massoniana. ► UV-B radiation would accelerate N and P turnover in C. Lanceolata forest.