14C Wiggle-Matching of the B-Tm Tephra, Baitoushan Volcano, China/North Korea

We performed accelerator mass spectrometry (AMS) radiocarbon dating and wiggle-matching of 2 wood samples from charred trunks of trees (samples A and B) collected from an ignimbrite deposit on the northeastern slope of the Baitoushan Volcano on the border of China and North Korea. The obtained calendar years for the eruption are cal AD 945–960 for sample A and cal AD 859–884 and cal AD 935–963 for sample B in the 2-σ range. These results are unable to determine the precise eruption age. The reason for the difference in reported ages may be due to volcanic gas emission prior to the huge eruption.

Destruction and Recovery of Vegetation Caused by the 2000-Year Eruption on Miyake-Jima Island, Japan

The active Mt. Oyama volcano on Miyake-jima Island in the Izu Islands, Japan, erupted in 2000 followed by large amounts of volcanic gas containing high concentrations of SO2has been emitted. The island ecosystem has been heavily damaged by the volcanic ash and gas. We detail the destruction and recovery of vegetation found in a 7-year study of 11 permanent plots from 2001 to 2007. Damage to vegetation by ash was worst near the crater in 2001. Trees began dying in 2001, apparently due to direct and/or indirect effects of volcanic gas emission. In contrast to the tree decline, two grass species,Miscanthus condensatusandCarex oshimensis, increased notably following the eruption, suggesting their high SO2and acidic soil tolerance.Miscanthus condensatusandC. oshimensiswere not dominant species in early stage of primary succession before the 2000-year eruption. In the vegetation recovery after the eruption, the tolerances to SO2and acidic soils are necessary for plant species to colonize on devastated sites.