Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Hoshika, Yasutomo*; Katata, Genki; Deushi, Makoto*; Watanabe, Makoto*; Koike, Takayoshi*; Paoletti, E.*
Scientific Reports (Internet), 5, p.9871_1 - 9871_8, 2015/05
Times Cited Count：84 Percentile：93.02(Multidisciplinary Sciences)The phytotoxic nature of tropospheric ozone can impair forest productivity and affects stomatal functions. Although a delay in stomatal responses (ozone-induced stomatal sluggishness) to fluctuating stimuli has a potential to change carbon and water balance in forests, this effect is not included in the current models for ozone risk assessment to forest. Here we examined effects of ozone-induced stomatal sluggishness on carbon gain and transpiration of global deciduous forests by combining land surface model and global atmospheric chemistry model. Ozone-induced stomatal sluggishness enhances stomatal ozone uptake resulting in facilitating a decline of forest carbon acquisition and also enhancing transpiration. Our findings are consistent with previous experimental and field observational results, indicating that forest trees suffer significant impairment of carbon and water balance through ozone-induced stomatal sluggishness.
Kajino, Mizuo*; Inomata, Yayoi*; Sato, Keiichi*; Ueda, Hiromasa*; Han, Z.*; An, J.*; Katata, Genki; Deushi, Makoto*; Maki, Takashi*; Oshima, Naga*; et al.
Atmospheric Chemistry and Physics, 12(24), p.11833 - 11856, 2012/12
Times Cited Count：45 Percentile：76.11(Environmental Sciences)A new aerosol chemical transport model, Regional Air Quality Model 2 (RAQM2), was developed to simulate Asian air quality. We implemented a simple version of a modal-moment aerosol dynamics model and achieved completely dynamic solution of a gas-to-particle mass transfer over a wide range of aerosol diameters from 1 nm to super micro m. To consider a variety of atmospheric aerosol properties, a category approach is utilized: aerosols are distributed into 4 categories, Aitken, accumulation, soot aggregates, and coarse mode. A regional-scale simulation was performed for the entire year of 2006, covering Northeast Asian region. Statistical analysis showed the model reproduced the regional-scale transport and transformation of the major inorganic anthropogenic and natural air constituents within factors of 2 to 5. Modeled size distributions of total weight and chemical components were consistent with the observations, indicating simulations of aerosol mixing types were successful.
Kajino, Mizuo*; Deushi, Makoto*; Maki, Takashi*; Aoyagi, Toshinari*; Igarashi, Yasuhito*; Mikami, Masao*; Inomata, Yayoi*; Katata, Genki
no journal, ,
no abstracts in English
Hoshika, Yasutomo*; Watanabe, Makoto*; Katata, Genki; De Marco, A.*; Deushi, Makoto*; Carriero, G.*; Koike, Takayoshi*; Paoletti, E.*
no journal, ,
Ozone (O
) enters leaves via stomata and causes a damage to leaves of trees. Modeling of stomatal conductance (g
) is considered as an essential factor to assess O impacts. In this presentation, our recent progress of research for the modeling of g under elevated O is summarized. First, we investigated g parameters of the Jarvis-type model for forest tree types throughout the world. The optimal temperature of g and g response to predawn water potential changed according to the growth conditions. Next, an optimization model of stomata including O effects was tested in free-air O exposure experiment on Siebold's beech in Japan. The optimal stomatal model explained O-induced stomatal closure in early summer. However, in late summer and autumn, the model did not explain the effects of O on g. This reflects the loss of closing response of stomata by O (stomatal sluggishness) such as under low light conditions. Finally, we examined the effects of O-induced stomatal sluggishness on carbon gain and transpiration of temperate deciduous forests in the Northern Hemisphere by combining a detailed multi-layer land surface model and a global atmospheric chemistry model. Our findings are consistent with previous experimental evidences, suggesting significant impairment of forest carbon and water balances attributed by O-induced stomatal sluggishness.
Hoshika, Yasutomo*; Katata, Genki; Watanabe, Makoto*; Deushi, Makoto*; Koike, Takayoshi*; Paoletti, E.*
no journal, ,
no abstracts in English
