著者
Junsei KONDO Makoto NAKAZONO Tsutomu WATANABE Tsuneo KUWAGATA
出版者
THE JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES
雑誌
JOURNAL OF JAPAN SOCIETY OF HYDROLOGY AND WATER RESOURCES (ISSN:09151389)
巻号頁・発行日
vol.5, no.4, pp.8-18, 1992-12-01 (Released:2009-07-23)
参考文献数
10
被引用文献数
18 24

全国の気象官署のデータを用いて熱収支的な方法によって, 森林における蒸発散量 (無降水日の蒸散量と降水日の遮断蒸発量の和) を見積もった.年蒸発散量は北日本では600-700mmy-1, 南日本では800-900mmy-1程度であり, 平衡蒸発量と比較的高い相関がある.また水面蒸発量より1.1-1.5倍も大きいことがわかった.
著者
Yasushi ISHIGOOKA Toshihiro HASEGAWA Tsuneo KUWAGATA Motoki NISHIMORI Hitomi WAKATSUKI
出版者
The Society of Agricultural Meteorology of Japan
雑誌
農業気象 (ISSN:00218588)
巻号頁・発行日
vol.77, no.2, pp.139-149, 2021 (Released:2021-04-10)
参考文献数
44

Rice is the most important cereal crop in Japan, and therefore the impact of projected climate change on its production and quality has been assessed using rice growth models accounting for the effects of rising temperature and atmospheric CO2 concentration ([CO2]) on important growth processes. Recent experimental studies, however, have shown some negative effects of interactions between [CO2] and temperature on yield and quality of rice which were not accounted for by previous impact assessments. This study examined the importance of [CO2]×temperature interactions in the nationwide impacts of climate change on grain yield and quality of rice in Japan by 2100. We introduced new functions accounting for the effects of interactions on yield. Then we adopted the acceleration by elevated [CO2] in the estimation of the occurrence of chalky grains, an indicator of appearance quality of rice. We applied the modified model to Japan at a spatial resolution of 1 km using 10 climate scenarios (5 Global Circulation Models×2 representative concentration pathways [RCPs]) from 1981 to 2100. The effects of the newly introduced negative effects of [CO2]×temperature were evaluated by comparing simulations with and without the interaction in each scenario. Nationwide production was estimated to decrease by up to 28% and the percentage of white chalky grains to increase up to 16% relative to the previous assessment results, especially in RCP8.5, in which larger increases were projected in both temperature and [CO2]. The result suggests that the positive effect of elevated [CO2], which had been expected to offset the negative effect of increased temperature on rice productivity, may be limited in the future, and rice quality degradation may be more severe than predicted previously.
著者
Mari Murai-HATANO Tsuneo KUWAGATA Hidehiro HAYASHI Junko Ishikawa-SAKURAI Masahisa MORIYAMA Masumi OKADA
出版者
日本農業気象学会
雑誌
農業気象 (ISSN:00218588)
巻号頁・発行日
vol.71, no.2, pp.124-135, 2015 (Released:2015-06-10)
参考文献数
40
被引用文献数
1 5

Transpiration, the evaporation from aerial parts of plants, is major driving force for the roots to uptake water from the soil. Aquaporins, the water channel proteins, are thought to play crucial roles in regulation of root hydraulic conductivity. Here we demonstrate that the evaporative demand plays a dominant role in the induction of specific aquaporins in rice (Oryza sativa) roots in seedlings grown hydroponically and then transferred to an open field. We found that the abundance of the root-specific aquaporin transcripts, OsPIP2;4, OsPIP2;5 and OsTIP2;1 at 8 a.m. is highly correlated with the evaporative demand in the morning (evaluated from potential evaporation averaged over 4 h before root sampling). Aquaporin isoforms with higher correlation to potential evaporation showed higher diurnal amplitude of their expression. Our study suggests that rice plants sense daily weather and responded to it by adjusting the expression of specific root aquaporin genes.