Name

YOKOSAWA, Masayuki

YOKOZAWA, Masayuki

Official Title

Professor

Affiliation

（School of Human Sciences）

Contact Information

Mail Address

Mail Address: myokoz@waseda.jp

URL

Web Page URL

https://sites.google.com/site/yokozawalab/my-homepage

http://www.researcherid.com/rid/O-2829-2014（Researcher ID）

https://scholar.google.co.jp/citations?hl=ja&user=FE6tAFcAAAAJ（Google Scholar Citation）

Grant-in-aids for Scientific Researcher Number

80354124

ORCID ID

0000-0001-7053-2465

Sub-affiliation

Faculty of Human Sciences（e-School (Internet Degree Program), School of Human Sciences）

Faculty of Human Sciences（Graduate School of Human Sciences）

Educational background・Degree

Educational background

-1985	BS, Tokyo Institute of Technology, Physics
-1987	MS, Tokyo Institute of Technology, Physics

Degree

Ph.D Thesis The University of Tokyo Ecology/Environment

Career

1987/04-2013/09	National Institute for Agro-Environmental Science
2013/10-2017/03	Shizuoka UniveristyDepartment of EngineeringProfessor

Academic Society Joined

American Geophysical Union

Research interests Career

Modeling the responses of terrestrial ecosystem to environmental changes

Evaluating the impacts of environmental changes on terrestrial ecosystem

Elucidating the inter-relations among components in terrestrial ecosystems

Paper

Effectively tuning plant growth models with different spatial complexity: a statistical perspective

Nakagawa Y, Yokozawa M, Ito A, Hara T.

Ecological Modelling 361p.95 - 1122017-

A model of silicon dynamics in rice: an analysis of the investment efficiency of Si transporters

Sakurai G, Yamaji N, Mitani-Ueno N, Yokozawa M, Ono K, Ma J.

Frontiers in Plant Science 8p.11872017-

Technological spillover in Japanese rice productivity under long-term climate change: Evidence from the spatial econometric model

Y. Kunimitsu R. Kudo T. Iizumi M. Yokozawa

Paddy and Water Environment 14p.131 - 1442016-

Indirect facilitation induced by competition among plants

Y. Nakagawa M. Yokozawa T. Hara

Nonlinear Theory and Its Applications 7p.126 - 1452016-

Complex network analysis reveals novel essential properties of competition among individuals in an even-aged plant population

Y. Nakagawa M. Yokozawa T. Hara

Ecological Complexity 26p.95 - 1162016-

Competition among plants can lead to an increase in aggregation of smaller plants around larger ones

Y. Nakagawa M. Yokozawa T. Hara

Ecological Modelling 301p.41 - 532015-

Inversely estimating the vertical profile of the soil CO2 production rate in a deciduous broadleaf forest using a particle filtering method

G. Sakurai S. Yonemura A.W. Kishimoto S. Murayama T. Ohtsuka M. Yokozawa

PLOS ONE 10p. e01190012015-

In silico simulation modeling revealed importance of the Casparian strips in efficient silicon uptake in rice roots

G. Sakurai A. Satake N. Yamaji N. Mitani-Ueno M. Yokozawa F.G. Feugier J. Ma

Plant and Cell Physiology 56p.631 - 6392015-

Modeling irrigation-based climate change adaptation in agriculture: Model development and evaluation in Northeast China

M. Okada T. Iizumi G. Sakurai N. Hanasaki T. Sakai K. Okamoto M. Yokozawa

Journal of Advances in Modeling Earth Systems 7p.1409 - 14242015-

Microhabitat locality allows multi-species coexistence in terrestrial plant communities

J.M. Tubay K. Suzuki T. Uehara S. Kakishima H. Ito A. Ishida K. Yoshida S. Mori J. Rabajante S. Morita M. Yokozawa J. Yoshimura

Scientific Reports 5p.153762015-

A meteorological forcing dataset for global crop modeling: development, evaluation and intercomparison

T. Iizumi M. Okada M. Yokozawa

Journal of Geophysical Research - Atmospheres 119p.363 - 3842014-

Applicability of empirical solar radiation models to altered climate

M. Okada T. Iizumi M. Yokozawa

Journal of Agricultural Meteorology 70p.13 - 232014-

How much has the increase in atmospheric CO2 directly affected past crop production?

G. Sakurai T. Iizumi M. Nishimori M. Yokozawa

Scientific Reports 4p.49782014-

Impacts of El Nino Southern Oscillation on the global yields of major crops

T. Iizumi J.J. Luo A.J. Challinor G. Sakurai M. Yokozawa H. Sakuma M.E. Brown T. Yamagata

Nature Communications 2014-

Contributions of historical changes in sowing date and climate to U.S. maize yield trend: An evaluation using large-area crop modeling and data assimilation

T. Iizumi G. Sakurai M. Yokozawa

Journal of Agricultural Meteorology 70p.73 - 902014-

Is long-term climate change beneficial or harmful for rice total factor productivity in Japan: Evidence from a panel data analysis

Y. Kunimitsu T. Iizumi M. Yokozawa

Paddy and Water Environment 12p.213 - 2252014-

A modeling approach for assessing rice crop cycle affected by flooding salinity intrusion and monsoon rains in the Mekong Delta, Vietnam

A. Kotera N.D. Nguyen T. Sakamoto T. Iizumi M. Yokozawa

Paddy and Water Environment 12p.343 - 3542014-

Dependency of parameter values of a crop model on the spatial scale of simulation

T. Iizumi Y. Tanaka G. Sakurai Y. Ishigooka M. Yokozawa

Journal of Advances in Modeling Earth Systems 6p.527 - 5402014-

Vertical soil-air CO2 dynamics at the Takayama deciduous broadleaf forest site

S. Yonemura M. Yokozawa G. Sakurai W.A. Kishimoto-Mo N. Lee S. Murayama K. Ishijima Y. Shirato H. Koizumi

Journal of Forest Research 18p.49 - 592013-

Prediction of seasonal climate-induced variations in global food production

T. Iizumi H. Sakuma M. Yokozawa J.J. Luo A.J. Challinor M.E. Brown G. Sakurai T. Yamagata

Nature Climate Change 3p.904 - 9082013-

Historical changes in global yields: Major cereal and legume crops from 1982 to 2006

T. Iizumi M. Yokozawa G. Sakurai M.I. Travasso V. Romanernkov P. Oettli T. Newby Y. Ishigooka J. Furuya

Global Ecology and Biogeography 23p.346 - 3572013-

An ensemble approach to the representation of subgrid-scale heterogeneity of crop phenology and yield in coarse-resolution large-area crop models

T. Iizumi G. Sakurai M. Yokozawa

Journal of Agricultural Meteorology 69p.243 - 2542013-

Inversely estimating temperature sensitivity of soil carbon decomposition by assimilating a turnover model and long-term field data

G. Sakurai M. Jomura S. Yonemura T. Iizumi Y. Shirato M. Yokozawa

Soil Biology and Biochemistry 46p.191 - 1992012-

Estimation of the damage area due to tropical cyclones using fragility curves for paddy rice in Japan

Y. Masutomi T. Iizumi K. Takahashi M. Yokozawa

Environmental Research Letters 7p.140202012-

Evaluation of CO2 exchange rates in a wetland ecosystem using the closed geosphere experiment facility

S. Suzuki M. Yokozawa K. Inubushi T. Hara M. Kimura S. Tsuga Y. Tako Y. Nakamura

Journal of Hydrometeorology 13p.966 - 9802012-

Impacts of land-use changes on surface warming rates and rice yield in Shikoku, Western Japan

R. Yoshida T. Iizumi M. Nishimori M. Yokozawa

Geophysical Research Letters 39p.L224012012-

Dangerous levels of climate change for agricultural production in China

F. Tao Z. Zhang M. Yokozawa

Regional Environmental Change 11p.41 - 482011-

Probabilistic evaluation of climate change impacts on paddy rice productivity in Japan

T. Iizumi M. Yokozawa M. Nishimori

Climatic Change 107p.391 - 4152011-

Modeling the multiple effects of temperature and radiation on rice quality

M. Okada T. Iizumi Y. Hayashi M. Yokozawa

Environmental Research Letters 6p.340312011-

Evaluation and intercomparison of downscaled daily precipitation indices over Japan in present-day climate: strengths and weaknesses of dynamical and bias-correction-type statistical downscaling methods

T. Iizumi M. Nishimori K. Dairaku S. Adachi M. Yokozawa

Journal of Geophysical Research 116p.D011112011-

Varying temporal and spatial effects of climate on maize and soybean affect yield prediction

G. Sakurai T. Iizumi M. Yokozawa

Climate Research 49p.143 - 1542011-

Projecting climate change impacts both on rice quality and yield in Japan

M. Okada T. Iizumi Y. Hayashi M. Yokozawa

Journal of Agricultural Meteorology 67p.283 - 2932011-

Tolerance of eddy covariance flux measurement

W. Kim J. Cho D. Komori M. Aoki M. Yokozawa S. Kanae T. Oki

Hydrological Research Letters 5p.73 - 772011-

Statistical downscaling with Bayesian inference: Estimating global solar radiation from reanalysis and limited observed data

T. Iizumi M. Nishimori M. Yokozawa A. Kotera N.D. Khang

International Journal of Climatology 32p.464 - 4802011-

Use of the RothC model to estimate carbon sequestration potential of organic matter application in Japanese arable soils

M. Yokozawa Y. Shirato T. Sakamoto S. Yonemura M. Nakai T. Ohkura

Soil Science and Plant Nutrition 56p.168 - 1762010-

Variations in water resources in the Vietnamese Mekong Delta in response to climate change and their impacts on rice production

N.D. Khang A. Kotera T. Iizumi T. Sakamoto M. Yokozawa

Journal of Agricultural Meteorology 66p.11 - 212010-

Potential predictability of local paddy rice yield variation using a crop model with local areal information

T. Iizumi K. Ishida M. Yokozawa M. Nishimori

Agricultural Information Research 19p.36 - 422010-

Diagnostics of climate model biases in summer temperature and warm-season insolation for the simulation of regional paddy rice yield in Japan

T. Iizumi M. Nishimori M. Yokozawa

Journal of Applied Meteorology and Climatology 49p.574 - 5912010-

More asymmetric tree competition brings about more evapotranspiration and less runoff from the forest ecosystems: A simulation study

M. Toda M. Yokozawa S. Emori T. Hara

Ecological Modelling 221p.2887 - 28982010-

Parameter estimation and uncertainty analysis of a large-scale crop model for paddy rice: Application of a Bayesian approach

T. Iizumi M. Yokozawa M. Nishimori

Agricultural and Forest Meteorology 149p.333 - 3482009-

Climate change, land use change, and China’s food security in the 21st century: an integrated perspective

F. Tao M. Yokozawa J. Liu Z. Zhang

Climatic Change 93p.433 - 4452009-

Modelling the impacts of weather and climate variability on crop productivity over a large area: A new process-based model development, optimization and uncertainty analysis

F. Tao M. Yokozawa Z. Zhang

Agricultural and Forest Meteorology 149p.831 - 8502009-

Mesh climate change data of Japan Ver.2 for climate change impact assessments under IPCC SRES A1B and A2

M. Okada T. Iizumi M. Nishimori M. Yokozawa

Journal of Agricultural Meteorology 65p.97 - 1092009-

Soil CO2 concentrations and their implications in conventional and no-tillage agricultural fields

S. Yonemura M. Yokozawa Y. Shirato S. Nishimura I. Nouchi

Journal of Agricultural Meteorology 65p.141 - 1492009-

Modelling the impacts of weather and climate variability on crop productivity over a large area: A new super-ensemble-based probabilistic projection

F. Tao Z. Zhang J. Liu M. Yokozawa

Agricultural and Forest Meteorology 149p.1266 - 12782009-

Development of impact functions on regional paddy rice yield in Japan for integrated assessment models

T. Iizumi M. Yokozawa M. Nishimori

Journal of Agricultural Meteorology 65p.179 - 1902009-

Analysis of rapid expansion of inland aquaculture and triple rice-cropping areas in a coastal area of the Vietnamese Mekong Delta using MODIS time-series imagery

T. Sakamoto V.P. Cao A. Kotera N.D. Khang M. Yokozawa

Landscape and Urban Planning 92p.34 - 462009-

Detection of yearly change in farming systems in the Vietnamese Mekong Delta from MODIS time-series Imagery

T. Sakamoto V.P.Cao A. Kotera N.D. Khang M. Yokozawa

JARQ 43p.173 - 1852009-

Foliage profiles of individual trees determine competition, self-thinning, biomass and NPP of a Cryptomeria japonica forest stand: A simulation study based on a stand-scale process-based forest model

M. Toda M. Yokozawa A. Sumida T. Watanabe T. Hara

Ecological Modelling 220p.2272 - 22802009-

A climatological analysis on recent decreasing trend of rice quality in Japan

M. Okada T. Iizumi Y. Hayashi M. Yokozawa

Journal of Agricultural Meteorology 65p.327 - 3372009-

Global warming

F. Tao Y. Hayashi Z. Zhang T. Sakamoto M. Yokozawa

Agricultural and Forest Meteorology 148p.94 - 1102008-

Combined Equations for Estimating Global Solar Radiation : Projection of Radiation Field over Japan under Global Warming Condition by Statistical Downscaling

T. Iizumi M. Nishimori M. Yokozawa

Journal of Agricultural Meteorology 64p.9 - 232008-

Land surface phenology dynamics and climate variation in the North East China Transect (NECT)

F. Tao M. Yokozawa Y. Hayashi Z. Zhang Y. Ishigooka, 1982-2000

International Journal of Remote Sensing 29p.5461 - 54782008-

Climate change impact on rice insurance payouts in Japan

T. Iizumi M. Yokozawa Y. Hayashi F. Kimura

Journal of Applied Meteorology and Climatology 47p.2265 - 22782008-

Sensitivity of salinity intrusion to sea level rise and river flow change in Vietnamese Mekong Delta -Impacts on availability of irrigation water for rice cropping

N.D. Khang A. Kotera T. Sakamoto M. Yokozawa

Journal of Agricultural Meteorology 64p.167 - 1762008-

Regional consequences of seawater intrusion on rice productivity and land use in coastal area of the Mekong River Delta

A. Kotera T. Sakamoto N.D. Khang M. Yokozawa

JARQ 42p.267 - 2742008-

Climate-crop yield relationships at province scale in China and the impacts of recent climate trend

F. Tao M. Yokozawa J. Liu Z. Zhang

Climate Research 38p.83 - 942008-

Simulating the carbon balance of a temperate larch forest under various meteorological conditions

M. Toda M. Yokozawa A. Sumida T. Watanabe T. Hara

Carbon Balance and Management 2(6) 2007-

Detecting temporal changes in the extent of annual flooding within the Cambodia and the Vietnamese Mekong Delta from MODIS time-series imagery

T. Sakamoto N.D. Khang A. Kotera H. Ohno N. Ishitsuka M. Yokozawa

Remote Sensing of Environment 109p.295 - 3132007-

Determining the spatial pattern of rice cropping schedules using time-series satellite imagery of the Red River Delta, Vietnam

A. Kotera T. Sakamoto M. Yokozawa

International Journal of Geoinformatics 3p.1 - 82007-

Spatio-temporal distribution of rice phenology and cropping systems in the Mekong Delta with special reference to the seasonal water flow of the Mekong and Bassac rivers

T. Sakamoto N. Van Nhan H. Ohno N. Ishitsuka M. Yokozawa

Remote Sensing of Environment 100p.1 - 162006-

How to analyze long-term insect population dynamics under climate change: 50-year data of three insect pests in paddy fields

K. Yamamura M. Yokozawa M. Nishimori Y. Ueda T. Yokosuka

Population Ecology 48p.31 - 482006-

Acid hydrolysis to partition plant material into decomposable and resistant fraction for use in the Rothamsted carbon model

Y. Shirato M. Yokozawa

Soil Biology and Biochemistry 38p.812 - 8162006-

A chamber system with automatic opening and closing for continuously measuring soil respiration based on an open-flow dynamic method

S. Suh Y. Chun N. Chae J. Kim J. Lim M. Yokozawa M. Lee J. Lee

Ecological Research 21p.405 - 4142006-

Climate changes and trends in phenology and yields of field crops in China, 1981-2000

F. Tao M. Yokozawa Y. Xu Y. Hayashi Z. Zhang

Agricultural and Forest Meteorology 138p.82 - 922006-

Impact of global warming on rice production in Japan based on five coupled atmosphere-ocean GCMs

T. Iizumi ME. Hori M. Yokozawa H. Nakagawa Y. Hayashi F. Kimura

SOLA 2p.156 - 1592006-

Assessing the impacts of climate change on early rice yields in the main rice areas of China

F. Yao Y. Xu E. Lin M. Yokozawa

Climatic Change 80p.395 - 4092006-

Testing the Rothamsted carbon model against long-term experiments on Thai upland soils

Y. Shirato K. Paisancharoen P. Sangtong C. Nakviro M. Yokozawa N. Matsumoto

European Journal of Soil Science 56p.179 - 1882005-

A perspective of water resources in China: Ineractions between climate and soil degradation

F. Tao M. Yokozawa Y. Hayashi E. Lin

Climatic Change 68p.169 - 1972005-

Risk Analyses of Rice Yield to Seasonal Climate Variability in China

F. Tao M. Yokozawa

Journal of Agricultural Meteorology 60p.885 - 8872005-

Remote sensing of crop production in China by production efficiency models: models comparisons, estimates and uncertainties

F. Tao M. Yokozawa Z. Zhang Y. Xu Y. Hayashi

Ecological Modelling 183p.385 - 3962005-

A crop phenology detection method using time-series MODIS data

T. Sakamoto M. Yokozawa H. Toritani M. Shibayama N. Ishizuka H. Ohno

Remote Sensing of Environment 96p.366 - 3742005-

Applying the Rothamsted Carbon Model for long-term experiments on Japanese paddy soils and modifying it with simple tuning of decomposition rate

Y. Shirato M. Yokozawa

Soil Science and Plant Nutrition 51p.405 - 4152005-

Future agricultural water resources and agricultural production in China - Interactions between climate change and soil degradation

F. Tao M. Yokozawa

Journal of Agricultural Meteorology 60p.1169 - 11742005-

Space-time variation of climate condition for major cereal cultivation areas: current status and future projection

M. Yokozawa F. Tao T. Sakamoto

Chinese Journal of Agricultural Meteorology 26p.1 - 62005-

Developing a multilayered integrated numerical model of surface physics-growing plants interaction, MINoSGI

T. Watanabe M. Yokozawa S. Emori K. Takata A. Sumida T. Hara

Global Change Biology 10p.963 - 9822004-

Risk analysis of cropland suitability in China under climatic variability and change

M. Yokozawa F. Tao T. Sakamoto

Crop, Environment and Bioinformatics 1p.264 - 2712004-

Climatological and agricultural production variability in China in association with East Asia summer monsoon and El Nino southern oscillation

F. Tao M. Yokozawa Z. Zhang Y. Hayashi H. Grassl H. Fu

Climate Research 28p.23 - 302004-

Future climate change the agricultural water cycle and agricultural production in China

F. Tao M. Yokozawa Y. Hayashi E. Lin

Agriculture Ecosystems and Environment 95p.203 - 2152003-

Mesh climate data for evaluating climate change impacts in Japan under gradually increasing atmospheric CO2 concentration

M. Yokozawa S. Goto Y. Hayashi H. Seino

Journal of Agricultural Meteorology 59p.117 - 1302003-

Terrestrial water cycle and the impact of climate change

F. Tao M. Yokozawa Y. Hayashi E. Lin

Ambio 32p.295 - 3012003-

Changes in the southwest monsoon mean daily rainfall intensity in Sri Lanka: relationship to the El Nino-Southern Oscillation

E. Ranatunge B.A. Malmgren Y. Hayashi T. Mikami W. Morishima M. Yokozawa M. Nishimori

Palaeogeography, Paleoclimatology, Paleoecology 197p.1 - 142003-

Changes in agricultural water demands and soil moisture in China over the last half-century and their effects on agricultural production

F. Tao M. Yokozawa Y. Hayashi E. Lin

Agricultural and Forest Meteorology 118p.251 - 2612003-

Diurnal change of carbon dioxide flux from bare soil in agricultural field in Japan

T. Nakadai M. Yokozawa H. Ikeda H. Koizumi

Applied Soil Ecology 19p.161 - 1712002-

Prediction of a geographical shift in the prevalence of rice stripe virus disease transmitted by the small brown planthopper, Laodelphax striatellus (Fallen) (Hemiptera: Delphacidae), under global warming

K. Yamamura M. Yokozawa

Applied Entomology and Zoology 37p.181 - 1902002-

Diurnal and seasonal changes in soil respiration in a Japanese grapevine orchard and their dependence on temperature and rainfall

S. Sekikawa H. Koizumi T. Kibe M. Yokozawa T. Nakano S. Mariko

Journal of the Japanese Agricultural Systems Society 18p.44 - 542002-

Multivariate statistical analysis of the seasonal rainfall regimes of the Guinea-Fouta Djallon Mountains of West Africa

S. Kamara T. Kuruppuarachchi E.R. Ranatunge Y. Hayashi M. Yokozawa M. Nishimori T. Mikami

Journal of Agricultural Meteorology 58p.171 - 1832002-

Seasonal structure of monsoon rainfall organization in Bangladesh as revealed from principal component analysis

T. Kuruppuarachchi E.R. Ranatunge Y. Hayashi M. Yokozawa M. Nishimori

Newsletter of Climate Impacts and Application 19p.39 - 462001-

Interclonal differences, plasticity and trade-offs of life history traits of Cyperus esculentus in relation to water availability

B. Li T. Shibuya Y. Yogo T. Hara M. Yokozawa

Plant Species Biology 16p.193 - 2072001-

Model analysis to the influences of soil diffusivity on CO and H2 uptake by soil

S. Yonemura M. Yokozawa S. Kawashima H. Tsuruta

Tellus B52p.919 - 9332000-

A process-based model for the global estimation of CH4- and CO-uptake strength by soils

S. Yonemura M. Yokozawa

World Resources Review 12p.149 - 1702000-

Measurement of CO2 fluxes from soil and snow surfaces with open dynamic chamber technique

S. Mariko N. Nishimura W. Mo Y. Matsui M. Yokozawa S. Sekikawa H. Koizumi

Environmental Science 13p.69 - 742000-

Concentration of carbon monoxide and methane at two heights above a grass field and their deposition onto the field

S. Yonemura A. Miyata M. Yokozawa

Atmospheric Environment 34p.5007 - 50142000-

Global vs. local coupling models and theoretical stability analysis of size-structure dynamics in plant populations

M. Yokozawa T. Hara

Ecological Modelling 118p.61 - 721999-

Effects of competition mode on the spatial pattern dynamics of wave regeneration in subalpine tree stands

M. Yokozawa Y. Kubota T. Hara

Ecological Modelling 118p.73 - 861999-

Size hierarchy and stability in competitive plant populations

M. Yokozawa

Bulletin of Mathematical Biology 61p.949 - 9611999-

Effects of competition mode on spatial pattern dynamics in plant communities

M. Yokozawa Y. Kubota T. Hara

Ecological Modelling 106p.1 - 161998-

A weather generator for the prediction of crop yields under changeable climates

Y. Hayashi M. Yokozawa S. Yamakawa H. Toritani

Journal of Agricultural Meteorology 52p.745 - 7481997-

Crown architecture and species coexistence in plant communities

M. Yokozawa Y. Kubota T. Hara

Annals of Botany 78p.437 - 4471996-

Foliage profile, size structure and stem diameter-plant height relationship in crowded plant populations

M. Yokozawa T. Hara

Annals of Botany 76p.271 - 2851995-

Effects of physiological and environmental variations on size-structure dynamics in plant populations

T. Hara M. Yokozawa

Annals of Botany 73p.39 - 511994-

A canopy photosynthesis model for the dynamics of size structure and the competition mode in plant populations

M. Yokozawa T. Hara

Journal of Agricultural Meteorology 48p.827 - 8301993-

A canopy photosynthesis model for the dynamics of size structure and self-thinning in plant populations

M. Yokozawa T. Hara

Annals of Botany 70p.305 - 3161992-

Competition between the Neel and the effective singlet states in spin-1/2 alternating Heisenberg-Ising antiferromagnet in one dimension

H. Nishimori K. Okamoto M. Yokozawa

Journal of the Physical Society of Japan 56p.4126 - 41331987-

Dynamic measurements of earthworm respiration.

Yonemura S, Kaneda S, Kodama N, Sakurai G, Yokozawa M.

Journal of Agricultural Meteorology Peer Review Yes 2018/12-2018/12

A model of silicon dynamics in rice: An analysis of the investment efficiency of Si transporters

Sakurai, Gen; Yamaji, Naoki; Mitani-Ueno, Namiki; Yokozawa, Masayuki; Ono, Keisuke; Ma, Jian Feng

Frontiers in Plant Science 82017/07-2017/07

Outline：© 2017 Sakurai, Yamaji, Mitani-Ueno, Yokozawa, Ono and Ma. Silicon is the second most abundant element in soils and is beneficial for plant growth. Although, the localizations and polarities of rice Si transporters have been elucidated, the mechanisms that control the expression of Si transporter genes and the functional reasons for controlling expression are not well-understood. We developed a new model that simulates the dynamics of Si in the whole plant in rice by considering Si transport in the roots, distribution at the nodes, and signaling substances controlling transporter gene expression. To investigate the functional reason for the diurnal variation of the expression level, we compared investment efficiencies (the amount of Si accumulated in the upper leaf divided by the total expression level of Si transporter genes) at different model settings. The model reproduced the gradual decrease and diurnal variation of the expression level of the transporter genes observed by previous experimental studies. The results of simulation experiments showed that a considerable reduction in the expression of Si transporter genes during the night increases investment efficiency. Our study suggests that rice has a system that maximizes the investment efficiency of Si uptake.

Effectively tuning plant growth models with different spatial complexity: A statistical perspective

Nakagawa, Yoshiaki; Yokozawa, Masayuki; Ito, Akihiko; Hara, Toshihiko

Ecological Modelling 361p.95 - 1122017/10-2017/10

ISSN：03043800

Outline：© 2017 Elsevier B.V. Forest gap models (non-spatial, patch- and individual-based models) and size structure models (non-spatial stand models) rely on two assumptions: the mean field assumption (A-I) and the assumption that plants in one patch do not compete with plants in other patches (A-II). These assumptions lead to differences in plant size dynamics between these models and spatially explicit models (or observations of real forests). Therefore, to more accurately replicate dynamics, these models require model tuning by (1) adjusting model parameter values or (2) introducing a correction term into models. However, these model tuning methods have not been systematically and statistically investigated in models using different patch sizes. We used a simple spatially explicit model that simulated growth and competition processes, and rewrote it as patch models. The patch sizes of the patch models were set between 4 and 1500 m 2 . First, we estimated the parameter values (the intrinsic growth rate, metabolic loss, competition coefficient, and competitive asymmetry) of these models that best reproduce plant size growth under competition using field data from a Sakhalin fir stand, and compared the parameter values among the models. Second, we introduced correction terms into the patch models and estimated the optimal correction term for reproducing plant size growth under competition using the field data. The estimated parameter values of the patch models for all patch sizes differed greatly from those of the spatially explicit models. Therefore, parameter values should not be shared between spatially explicit models and patch models. In addition, the parameter value sets for the models with small patches differed from those with large patches. This is because parameter values for small patches mainly improve biases of A-II, while those for large patches mainly improve biases of A-I. Therefore, parameter values should not be shared between patch models with small patches and with large patches. The estimated correction term in the patch models with large patches excluded the competitive effects of small and medium-sized plants on their neighbors, even though these effects exist in real stands. This exclusion can be ascribed to the discrepancy between their competition in real plant populations and A-I. Therefore, the competitive effects of small and medium-sized plants should not be included in patch models with large patches. Finally, the reproducibility of the models tuned with correction terms was higher than those with adjusted parameters.

Vertical soil-air CO2 dynamics at the Takayama deciduous broadleaved forest AsiaFlux site

Yonemura, Seiichiro; Yokozawa, Masayuki; Sakurai, Gen; Kishimoto-Mo, Ayaka W.; Lee, Nayeon; Lee, Nayeon; Murayama, Shohei; Ishijima, Kentaro; Shirato, Yasuhito; Koizumi, Hiroshi; Koizumi, Hiroshi

Journal of Forest Research 18(1) p.49 - 592013/01-2013/01

ISSN：13416979

Outline：At the Takayama deciduous broadleaved forest Asiaflux site in Japan, the ecosystem carbon dynamics have been studied for more than two decades. In 2005, we installed non-dispersive infrared CO 2 sensors in the soil below the site's flux tower to systematically study vertical soil-air CO 2 dynamics and explain the behavior of soil surface CO 2 efflux. Soil-air CO 2 concentrations measured from June 2005 through May 2006 showed sinusoidal variation, with maxima in July and minima in winter, similar to the soil CO 2 effluxes measured simultaneously using open-flow chambers. Soil-air CO 2 concentrations increased with soil depth from 5 to 50 cm: from 2,000 to 8,000 ppm in the summer and from 2,000 to 3,000 ppm in the winter under snow. Summer soil-air CO 2 concentrations were positively correlated with soil moisture on daily and weekly scales, indicating that the Oi, Oe, and A horizons, where decomposition is accelerated by high-moisture conditions, contributed substantially to CO 2 emissions. This result is consistent with the short residence time (about 2 h) of CO 2 in the soil and larger emissions in shallow soil layers based on our diffusion model. We revealed for the first time that soil-air CO 2 concentrations in winter were correlated with both snow depth and wind speed. CO 2 transfer through the snow was hundreds of times the gas diffusion rates in the soil. Our estimate of the CO 2 efflux during the snow-cover season was larger than previous estimates at TKY, and confirmed the important contribution of the snow-cover season to the site's carbon dynamics. © 2012 The Japanese Forest Society and Springer Japan.

Books And Publication

Characterizing the reliability of global crop prediction based on seasonal climate forecasts

Indo-Pacific Climate Variability and Predictability. (eds., Behera K. Yamagata T.)(Sharing writing)

World Scientific Publishing2016-

Responsible Number of Pages：281-304

The Mode of Competition and Spatial Pattern Formation in Plant Communities

Morphogenesis and Pattern Formation in Biological Systems. (eds., Sekimura, T., Noji, S., Ueno, N. and Maini, P.K.)(Sharing writing)

Springer-Verlag2003-

Responsible Number of Pages：237-246

Research Grants & Projects

Grant-in-aids for Scientific Research Adoption Situation

Research Classification：

Modeling forest ecosystem responses to environmental change implementing spatial heterogeneity of trees

2018/-0-2021/-0

Allocation Class：￥4290000

Research Classification：

Systemic Risk in the World Food Market and Trade Liberalization under Climate Change: Evaluation by the Multi-regional DSGE Model

2016/-0-2020/-0

Allocation Class：￥16120000

Research Classification：

Forest determinant factors and the effects of precipitation shift under global climate changeo in Thailand

2016/-0-2021/-0

Allocation Class：￥40950000

Research Classification：

Elucidating the impacts of variations in major cereal crop productions due to abnormal weather condition on world food supply, demand and population under malnutrition

2014/-0-2018/-0

Allocation Class：￥15600000

Research Classification：

Dynamic study of soil gas exchange

2011/-0-2014/-0

Allocation Class：￥20020000

Research Classification：

Vulnerability evaluation on rice production in response to sea-level rise in Vietnam Mekong Delta

Allocation Class：￥10790000

Research Classification：

Long-term durability of carbon sequestration in terrestrial ecosystems

Allocation Class：￥38090000

Research Classification：

Evaluation of soil carbon sequestration in a small basin ecosystem

Allocation Class：￥13400000

Research Classification：

Systemic regulation of whole-plant metabolic scaling including roots

2015/-0-2018/-0

Allocation Class：￥3900000

On-campus Research System

Special Research Project

異常気象による作物生産性変動のナウキャスティングに向けたモデル開発

2018

Research Results Outline：　流域スケールの作物生産性変動をナウキャスト（作物の生産性を収穫の数ヶ月前に予測）するシステムに組み込むモデルのプロトタイプ開発を行った。対象であるサ　流域スケールの作物生産性変動をナウキャスト（作物の生産性を収穫の数ヶ月前に予測）するシステムに組み込むモデルのプロトタイプ開発を行った。対象であるサトウキビなど糖料作物はバイオマス量よりも植物体に含まれる糖度量の推定が経済的側面から重要であること...　流域スケールの作物生産性変動をナウキャスト（作物の生産性を収穫の数ヶ月前に予測）するシステムに組み込むモデルのプロトタイプ開発を行った。対象であるサトウキビなど糖料作物はバイオマス量よりも植物体に含まれる糖度量の推定が経済的側面から重要であることから、作物の生育環境に応じた糖度特性決定に関するモデル化を行うとともに、JAMSTEC/APLから出力される気象環境データの時間空間分解能の観点からモデルに取り込む素過程の簡略化または高度化を行った。登熟過程に焦点をあてて、環境条件とスクロース貯蔵過程との関係の経験的モデルとして定式化した。そのモデルについて、貯蔵スクロース収量の環境応答を調べた。

Lecture Course

Course Title	School	Year	Term
Basic Seminar I	School of Human Sciences	2020	spring semester
Basic Seminar I	School of Human Sciences	2020	spring semester
Introduction to Human Sciences	School of Human Sciences	2020	fall quarter
Introduction to Human Sciences	School of Human Sciences	2020	fall quarter
Basic Ecology	School of Human Sciences	2020	fall semester
Agricultural Meteorology	School of Human Sciences	2020	spring semester
Eco-Informatics	School of Human Sciences	2020	an intensive course(spring)
Seminar I(Arable Land environment)	School of Human Sciences	2020	spring semester
Seminar II (Arable Land environment)	School of Human Sciences	2020	fall semester
Introduction to Human Sciences	School of Human Sciences (Online Degree Program)	2020	summer quarter
Agricultural Meteorology	School of Human Sciences (Online Degree Program)	2020	fall semester
Arable Land Environment	Graduate School of Human Sciences	2020	spring semester
Arable Land Environment	Graduate School of Human Sciences	2020	fall semester
Arable Land Environment(1)	Graduate School of Human Sciences	2020	spring semester
Arable Land Environment(1)	Graduate School of Human Sciences	2020	fall semester
Arable Land Environment(2)	Graduate School of Human Sciences	2020	spring semester
Arable Land Environment(2)	Graduate School of Human Sciences	2020	fall semester
Ecological Modelling	Graduate School of Human Sciences	2020	summer quarter
Agri-Informatics	Graduate School of Human Sciences	2020	an intensive course(spring)
Arable Land Environment(D) A	Graduate School of Human Sciences	2020	spring semester
Arable Land Environment(D) B	Graduate School of Human Sciences	2020	fall semester