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

Toshichika Iizumi*, Yukiko Tanaka, Gen Sakurai, Yasushi Ishigooka, Masayuki Yokozawa


研究成果: Article査読

21 被引用数 (Scopus)


Reliable regional-scale representation of crop growth and yields has been increasingly important in earth system modeling for the simulation of atmosphere-vegetation-soil interactions in managed ecosystems. While the parameter values in many crop models are location specific or cultivar specific, the validity of such values for regional simulation is in question. We present the scale dependency of likely parameter values that are related to the responses of growth rate and yield to temperature, using the paddy rice model applied to Japan as an example. For all regions, values of the two parameters that determine the degree of yield response to low temperature (the base temperature for calculating cooling degree days and the curvature factor of spikelet sterility caused by low temperature) appeared to change relative to the grid interval. Two additional parameters (the air temperature at which the developmental rate is half of the maximum rate at the optimum temperature and the value of developmental index at which point the crop becomes sensitive to the photoperiod) showed scale dependency in a limited region, whereas the remaining three parameters that determine the phenological characteristics of a rice cultivar and the technological level show no clear scale dependency. These results indicate the importance of using appropriate parameter values for the spatial scale at which a crop model operates. We recommend avoiding the use of location-specific or cultivar-specific parameter values for regional crop simulation, unless a rationale is presented suggesting these values are insensitive to spatial scale.

ジャーナルJournal of Advances in Modeling Earth Systems
出版ステータスPublished - 2015 8月 21

ASJC Scopus subject areas

  • 地球変動および惑星変動
  • 環境化学
  • 地球惑星科学(全般)


「Dependency of parameter values of a crop model on the spatial scale of simulation」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。