Vegetation changes from 1984 to 2008 on Mount Usu, northern Japan, after the 1977–1978 eruptions

Abstract

The revegetation patterns after volcanic eruptions were monitored annually on Mount Usu, northern Japan, using over 25 years to detect successional changes. The vegetation was monitored by 2 × 5 m plots from 1984 and 2008 and by 5 × 5 m plots that were enlarged from the original plots from 1994 to 2008 due to increasing vegetation height. The thick tephra from these eruptions destroyed the former vegetation in 1977 and 1978. Diversity indexes were calculated, and nonmetric multidimensional scaling (NMDS) was conducted using the vegetation data with environmental factors. The cover of dominant species was higher in the large plots probably due to the vegetative expansion. Species richness and diversity continued to increase annually for 30 years after the eruptions. Well‐established plants were perennial forbs and trees and the species replacement occurred consistently. NMDS of small plot data suggested that elevation was related to the first axis, and year, litter volume and distance to the caldera rim were related to the second axis. Plot scores on the first axis suggested that deterministic factors, that is, elevation and its related factors, produced vegetation convergence but those on the second axis suggested that the vegetation change was in response to stochastic factors, such as litter accumulation and its related unmeasured factors, with year. The results indicated that the convergence or divergence was determined by the conflict between the net effects of deterministic and stochastic factors on vegetation development.

Comparison of vegetation patch dynamics after the eruptions of the volcano Mount Usu, northern Japan, in 1977–1978 and 2000, detected by imagery chronosequence

“…Because the elevation differed greatly between the summit and Konpira, the elevation and its related factors should be more severe at the summit. Small elevational differences were related to the vegetation development patterns at the summit of Mount Usu (Tsuyuzaki, 2019), and high elevation slowed down succession on Mount Ontake, central Japan, because of the short growing season and low species diversity (Nakashizuka, Iida, Suzuki, & Tanimoto, 1993). Other factors, such as soil properties, species compositions and stochastic events also affect patch dynamics (del Moral et al, 2010; Wilmshurst & McGlone, 1996; Zobel & Antos, 2017).…”

“…Other factors, such as soil properties, species compositions and stochastic events also affect patch dynamics (del Moral et al, 2010; Wilmshurst & McGlone, 1996; Zobel & Antos, 2017). However, soil properties did not differ greatly between the two sites, and the species composition was comparable (Otaki, Takeuchi, & Tsuyuzaki, 2016; Tsuyuzaki, 2019). Therefore, the stress caused by the elevation and its related environmental factors seemed to determine slow patch dynamics at the summit.…”

Review of Local and Global Impacts of Volcanic Eruptions and Disaster Management Practices: The Indonesian Example

“…The fragmentation of the volcanic material into fine ash and lapilli creates soils that are rich yet light to work with, and the volcanoes of Indonesia all have vegetated slopes. This land-cover often gets disrupted by eruption processes and there is a balance of vegetation destruction and revegetation occurring on volcanoes (e.g., [63]). This changing balance is often used to determine the extent of the volcanic deposits [64].…”

Phytoliths as an indicator of change in vegetation related to the huge volcanic eruption at 7.3 ka in the southernmost part of Kyushu, southern Japan

“…Although in modern days, the continuous monitoring of vegetation post-eruption enables us to evaluate vegetation changes (e.g. del Moral et al, 2012; Tsuyuzaki, 2019), such monitoring has only been available in the last hundred years. Furthermore, the influence of large historical eruptions on past and current vegetation is still poorly understood.…”