CALIBRATION OF THE CERES–MAIZE MODEL FOR SIMULATING SITE–SPECIFIC CROP DEVELOPMENT AND YIELD ON CLAYPAN SOILS

Abstract

Crop simulation models have historically been used to predict field average crop development and yield under alternative management and weather scenarios. The objective of this research was to calibrate and test a new version of the CERES-Maize model, modified to improve the simulation of site-specific crop development and yield. Seven sites within a field located in central Missouri were selected based on landscape position, elevation, depth to a claypan soil horizon, and past yield history. Detailed monitoring of crop development and soil moisture during the 1997 season provided data for calibration and evaluation of model performance at each site. Mid-season water stress caused a large variation in measured yield with values ranging from 2.6 Mg ha-1 in the eroded side-slope areas to 10.1 Mg ha-1 in the deeper soils located in the low areas of the field. The model was calibrated against measured data for root zone soil moisture content, leaf area index, and grain yield. The results demonstrated that modifications included in the model to simulate root growth and development are important in soils with a high-clay restrictive layer such as the claypan soils. Although the model performed well in simulating yield variability, simulated leaf area indices were below measured values at five out of seven monitoring sites, suggesting a need for model improvements. Results showed that accurate simulation of crop growth and development for areas of the study field that receive run-on or subsurface flow contributions from upland areas will require enhancement of the model to account for the effects of these processes.

Determination of potential management zones from soil electrical conductivity, yield and crop data

“…Several studies have indicated that homogenous management zones could be used as an alternative to grid soil sampling and to develop nutrient maps for variable rate fertilizer application (Khosla and Alley, 1999;Fleming et al, 2000a). Spatially coherent areas within fields may also be useful in relating yield to soil and topographic parameters for crop-modeling evaluation (Fraisse et al, 2001a While methods for delineating management zones vary widely in the information used, usually they are based on soil and yield information possibly over several years (Fraisse et al, 2001b;Fleming et al, 2000b). Many researches used the soil and/or relief information to define management zones.…”

Eficiência do modelo ceres-maize na predição da produtividade de milho em áreas com presença de variabilidade espacial

“…Trabalhos desenvolvidos por Fraisse et al (2001) e Irmak et al (2001), tem mostrado que modelos do DSSAT podem estimar de forma adequada as produtividades, quando amostragens adequadas são realizadas em áreas com presença de variabilidade espacial do solo.…”

“…Desta maneira, a tendência observada evidencia que, com amostragens apropriadas em locais com presença de variabilidade espacial, os modelos do DSSAT podem estimar adequadamente produtividades variáveis, coincidindo com Fraisse et al (2001), Irmak et al (2001) e Paz et al (2001). TABELA 6 Relação de valores dos parâmetros genéticos correspondentes às diferentes parcelas experimentais, obtidos após à calibração de P1, P2 e P5.…”

Integration of remote sensing and crop growth modeling for nitrogen management decision support in corn

“…This model utilizes carbon, nitrogen, and water balance principles to simulate, in homogenous units, the daily processes that occur during plant growth and development. The model has been shown to adequately simulate corn growth, development, and yield on plot-level, field-level, and regional scales for many locations around the world (Hodges et al, 1987;Carberry et al, 1989;Liu et al, 1989;Jagtap et al, 1993;Pang et al, 1998;Fraisse et al, 2001).…”

“…(Fraisse et al, 2001) and/or tile drains . A variety of techniques have been explored for implementing calibration procedures to estimate model input parameters.…”