Effect of sulfur dioxide (SO₂) on growth and physiological activity in Alnus sieboldiana at Miyakejima Island in Japan

Abstract

We used a physiological approach to investigate the effect of sulfur dioxide (SO2) on Alnus sieboldiana Matsum. (A. sieboldiana) and symbiotic Frankia spp. in Miyakejima Island, which was devastated by volcanic action in July of 2000. In April of 2008, three study sites were chosen in the forest of Miyakejima Island, and were categorized as high, medium, or low in relation to their sulfur dioxide concentration (volcanic gas). Nine A. sieboldiana trees were selected from naturally regenerated forest at each site. The higher the SO2 concentration at the study site, the lower was the photosynthetic rate and the maximum photochemical efficiency of PSII (Fv/Fm) of A. sieboldiana and its apparent quantum yield. The acetylene reduction rate of the Frankia spp. symbiotic with A. sieboldiana was significantly less at the high SO2 concentration (p<0.05). The nitrogen concentration in their leaves remained high, however. There was no significant difference in the chlorophyll concentration (Chl a + b) in leaves from the three sites. The photosynthetic nitrogen use efficiency decreased significantly in sites with a high SO2 concentration, however. As a result, A. sieboldiana regenerated at the sites with high or medium SO2 concentration underwent approximately 50–70 % less growth than at the site with a low SO2 concentration.

Photosynthetic Properties of Miscanthus condensatus at Volcanically Devastated Sites on Miyake-jima Island

“…In terms of C 3 plants, including trees, there are a few studies comparable to our data. Choi et al reported that the A max value for A. sieboldiana (an N-fixing C 3 tree species) at Miyake-jima Island [ 12 ], in a site with low exposure to the disturbances from the 2000 eruption, was 12 µmol·m −2 ·s −1 . This value is lower than that recorded for M. condensatus, even though the study site was highly disturbed and had low soil N. In the volcanically devastated site of Mt.…”

“…For example, altered root morphology, improved resource use efficiency, resorption efficiency (e.g., N, P), and N-fixing ability are all important adaptation strategies that allow plants to cope with poor nutrient habitats. Many studies have focused on N-fixing pioneer species at new volcanically devastated sites [ 9 , 10 , 11 , 12 ], because N is scarce in new volcanic materials, such as lava, scoria, and volcanic ash [ 2 ]. However, there are also many pioneer species without the N-fixing ability in volcanic succession.…”

“…Leaf N content (N area ), leaf mass per area (LMA), and light-saturated photosynthetic rate (A max ) are the main leaf traits correlated with each other [ 17 , 18 ]. Numerous studies have found that N area is associated with abiotic factors, such as light availability [ 19 , 20 ], nutrient availability [ 21 , 22 ], temperature [ 23 , 24 ], fire regime [ 25 ], and volcanic gas [ 12 ]. The relationship between N area and these abiotic factors reflects the adaptive response of the plant to the local environmental conditions.…”

Photosynthetic Properties of Co-Occurring Pioneer Species on Volcanically Devastated Sites in Miyake-jima Island, Japan

“…The average values of N area for F. japonica and A max for A. sieboldiana are even higher than the leaf traits from the N-rich habitat (Table A1). This reflects the relatively higher ability of these species to resist the N-low conditions in this volcanic environment; these plants also show an extremely low N requirement and demonstrate more effective N use strategies than the Miyake-jima pioneer species [11,39].…”

“…Among these three species, A. sieboldiana (with N-fixing ability) can partially grow in volcanic N-deficiency deserts, as it has the ability to fix N in the atmosphere via symbiosis with nitrogen-fixers. Additionally, Choi et al [39] also proved its success in resisting high concentrations of volcanic gas (SO 2 ) in the Miyake-jima volcano. Regarding M. condensatus, our previous study [11] in the volcanically devastated site in Miyake-jima indicated that the relatively high light-saturated photosynthetic rate (A max ) and PNUE of M. condensatus were its adaptation advantages to volcanically N-deplete habitats.…”