Enhancing Agricultural Research and Precision Management for Subsistence Farming by Integrating System Models with Experiments

1 Cover

2 Series Page

3 Title Page

4 Copyright Page

5 Dedication Page

6 1 Introduction: System Models Integrated with Experiments Can Be Useful Tools to Develop Improved Management Practices for Subsistence Farming to Address Increased Intensification and Climate Change References

7 2 Modeling Soil Erosion Impacts and Trade‐Offs of Sustainable Land Management Practices in the Upper Tana Region of the Central Highlands in Kenya Abstract Introduction Materials and Methods Results and Discussion Conclusions Acknowledgments Abbreviations References

8 3 Using Crop Simulation Models as Tools to Quantify Effects of Crop Management Practices and Climate Change Scenarios on Wheat Yields in Northern Ethiopia Abstract Introduction Materials and Methods Results and Discussion Conclusions Acknowledgments Abbreviations References

9 4 The Role of Crop Simulation Modeling in Managing Fertilizer Use in Maize Production Systems in Northern Ghana Abstract Introduction Methodology Results and Discussions Conclusion Acknowledgment Abbreviations References

10 5 Modeling Water Dynamics for Assessing and Managing Ecosystem Services in India Abstract Introduction Modeling of Agro‐Ecosystem Services Modeling of Water‐Regulating Agro‐Ecosystem Services under Climate Change Summary Abbreviations References

11 6 Modeling Agricultural Hydrology and Water Productivity to Enhance Water Management in the Arid Irrigation District of China Abstract Introduction Materials and Methods Results Discussion Conclusions Acknowledgments Abbreviations References

12 7 Use of Data and Models in Simulating Regional and Geospatial Variations in Climate Change Impacts on Rice and Barley in the Republic of Korea Abstract Introduction Simulation of Grain Yields of Barley and Rice under Climate Change Varietal, Local, and Geographical Variations in Grain Yields of Barley and Rice in a Changing Climate Management Options and Outlines of the Geospatial Crop Projections under Climate Change as a Tool to Guide Management by Producers Summary and Conclusion Acknowledgments Abbreviations References

13 8 Constraints to Productivity of Subsistence Dryland Agroecosystems in the Fertile Crescent: Simulation and Statistical Modeling Abstract Introduction Materials and Methods Results and Discussion Conclusions Abbreviations References

14 Index

15 End User License Agreement

1 Chapter 2 Table 2.1 Mean soil loss from control plots (maize with no erosion measures... Table 2.2 Environmental input parameters per farm for the FarmDESIGN model... Table 2.3 Summary of farmer‐reported land management practice opportunities... Table 2.4 Three most preferred SLM practices by farms modeled in this study Table 2.5 Grass strip scenarios description (NapierStrips and BrachiariaStr... Table 2.6 Soil characteristics per farm and per plot and carbon stock from... Table 2.7 Farm area (m2) and percentage of total farm area under various le... Table 2.8 Estimation of soil loss per year per plot and per farming system...Table 2.9 Operating profit and gross margins per farm in US$ yr−1

2 Chapter 4Table 4.1 Soil data used in the modelTable 4.2 Genetic coefficients of the CERES‐Maize modelTable 4.3 Set of genetic coefficients derived for the three maize varieties

3 Chapter 5Table 5.1 Basic infiltration rate in different agro‐ecoregions of India...

4 Chapter 6Table 6.1 Soil physical properties of experimental areaTable 6.2 Values of the hydrological parameters for AWPM‐SGTable 6.3 Default and calibrated values of maize's physiological parameters...Table 6.4 Mean relative error, root mean square error, regression coefficie...Table 6.5 Water productivity and irrigation water productivity under variou...

5 Chapter 7Table 7.1 Statistical analysis of the future change impacts of CO2, tempera...

6 Chapter 8Table 8.1 Main agroecosystems, land use, management practices, problems, an...Table 8.2 Summary of methods, inputs, simulation, and statistical procedure...Table 8.3 Estimated effects of fixed factors (country, RCP and soils), cova...Table 8.4 Validation variance in annualized crop rotation yield explained b...Table 8.5 Coefficient of variation (CV%) of simulated and annualized crop r...Table 8.6 Correlation coefficients between matrices based on multivariate d...

1 Chapter 2 Figure 2.1 Map of the three sub‐watersheds in which the modeled farms are lo... Figure 2.2 Average slope (%) per elevation band (m) for the study sub‐waters...Figure 2.3 Inputs (bold colors) and outputs (patterns) for the farm N balanc...Figure 2.4 Greenhouse gas (GHG) emission intensity per farm and hectare indi...Figure 2.5 Changes through scenarios “maintenance,” “NapierStrips,” and “Bra...

2 Chapter 3Figure 3.1 Average maximum and minimum temperatures for the months in a year...Figure 3.2 Effect of planting dates on wheat yield at varying plant density...Figure 3.3 Relationship between wheat yield and fertilizer N application rat...Figure 3.4 Future dryland wheat yield and irrigated and dryland baseline yie...Figure 3.5 Future dryland wheat yield and irrigated and dryland baseline yie...Figure 3.6 Average percentage yield increase per increase in N fertilization...Figure 3.7 Relative yield increase due to increased N fertilizer rate and ch...Figure 3.8 Relationship between future dryland wheat yield and simulated (a)...

3 Chapter 4Figure 4.1 Map of northern Ghana indicating experimental sites and locations...Figure 4.2 Comparison of observed maize biomass yield response to inorganic...Figure 4.3 Comparison of observed maize grain yield response to inorganic N...Figure 4.4 Simulated N stress factors for leaf expansion of three maize vari...Figure 4.5 Simulated maize (Obatanpa) variability in response to N fertilize...Figure 4.6 Simulated water stress factors of three maize varieties under var...Figure 4.7 Simulated effects of plant population on the yield of maize grown...Figure 4.8 Simulated effects of plant population on the yield of maize grown...Figure 4.9 Average yield map of the Abontem (extra early maturity) maize var...Figure 4.10 Average yield map of Omankwa (early maturity) maize varieties at...Figure 4.11 Average yield map of the Obatanpa (intermediate maturity) maize...Figure 4.12 Average yield map of the Abontem (extra early maturity) maize va...Figure 4.13 Average yield map of the Omankwa (early maturity) maize variety...Figure 4.14 Average yield map of the Obatanpa (intermediate maturity) maize...Figure 4.15 Simulated mean N response curves for the three maize varieties a...

4 Chapter 5Figure 5.1 Ecosystem services provided by the agro‐ecosystem.Figure 5.2 Performance of dimensionless (a) cumulative infiltration, I*(t*),...Figure 5.3 Annual potential recharge from the soybean cropping system under...Figure 5.4