Persistent Link:
http://hdl.handle.net/10150/195783
Title:
Evaluation of Sustainable Agriculture Systems in Central Mexico
Author:
Fernandez-Reynoso, Demetrio Salvador
Issue Date:
2008
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
In Mexico, corn (Zea mays L.) is the most important crop (59% of its agriculture land) and the primary source of sediment yield. This study looks for alternatives to maintain corn productivity by means of sustainable soil and water conservation practices at central Mexico. In order to understand broad tendencies between soil erosion and crop productivity in the region, the EPIC (Erosion Productivity Impact Calculator) model was applied in the Texcoco's district as follows:1) Calibrate the model using 352 experimental corn plots established between 1972 and 1992 in 36 rural communities.2) Validate the model on a spatial basis, using GIS tools, by means of historic corn yields.3) Identify the most vulnerable areas where corn productivity is being affected by soil erosion.4) Analyze the relationship between soil erosion and crop productivity, over a 100 years of simulation, comparing the Current Management (CM) and the Recommended Management (RM) by governmental institutions.5) Evaluate the most feasible soil and water conservation practices for the region.From the calibration process, it was concluded that the EPIC model, under a wide range of environmental conditions, simulates very good corn yield (r2 between 0.88 and 0.90), annual runoff (r2=0.98), and annual sediment production (r2=0.96).Base on the official environmental inputs available in the region, the EPIC model can assess only a moderately strong relationship (r2=0.58) between the official historical crop records and the simulated ones.Comparison between CM and RM shows that the average crop yield in the region can be increased by 32.6% if RM were followed. Under the CM, the loss of soil fertility in the district reduces corn productivity by 3% over a hundred years. At least 50.0% of the region's agricultural area needs soil conservation practices, mainly on areas with slopes over 5%. If it is decided to grow corn under conventional till in such areas it is recommended to construct bench terraces in order to maintain soil erosion below 20 t/ha/yr. Corn under no till, besides control erosion, can also increase grain productivity by at least 40% (0.6 t/ha) by combining contouring, mulching, and manures.
Type:
text; Electronic Dissertation
Keywords:
EPIC model; Central Mexico; soil conservation; corn productivity; corn BMPs
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Natural Resources; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Zaimes, George
Committee Chair:
Guertin, D. Phillip; Lopes, Vicente L.

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleEvaluation of Sustainable Agriculture Systems in Central Mexicoen_US
dc.creatorFernandez-Reynoso, Demetrio Salvadoren_US
dc.contributor.authorFernandez-Reynoso, Demetrio Salvadoren_US
dc.date.issued2008en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractIn Mexico, corn (Zea mays L.) is the most important crop (59% of its agriculture land) and the primary source of sediment yield. This study looks for alternatives to maintain corn productivity by means of sustainable soil and water conservation practices at central Mexico. In order to understand broad tendencies between soil erosion and crop productivity in the region, the EPIC (Erosion Productivity Impact Calculator) model was applied in the Texcoco's district as follows:1) Calibrate the model using 352 experimental corn plots established between 1972 and 1992 in 36 rural communities.2) Validate the model on a spatial basis, using GIS tools, by means of historic corn yields.3) Identify the most vulnerable areas where corn productivity is being affected by soil erosion.4) Analyze the relationship between soil erosion and crop productivity, over a 100 years of simulation, comparing the Current Management (CM) and the Recommended Management (RM) by governmental institutions.5) Evaluate the most feasible soil and water conservation practices for the region.From the calibration process, it was concluded that the EPIC model, under a wide range of environmental conditions, simulates very good corn yield (r2 between 0.88 and 0.90), annual runoff (r2=0.98), and annual sediment production (r2=0.96).Base on the official environmental inputs available in the region, the EPIC model can assess only a moderately strong relationship (r2=0.58) between the official historical crop records and the simulated ones.Comparison between CM and RM shows that the average crop yield in the region can be increased by 32.6% if RM were followed. Under the CM, the loss of soil fertility in the district reduces corn productivity by 3% over a hundred years. At least 50.0% of the region's agricultural area needs soil conservation practices, mainly on areas with slopes over 5%. If it is decided to grow corn under conventional till in such areas it is recommended to construct bench terraces in order to maintain soil erosion below 20 t/ha/yr. Corn under no till, besides control erosion, can also increase grain productivity by at least 40% (0.6 t/ha) by combining contouring, mulching, and manures.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectEPIC modelen_US
dc.subjectCentral Mexicoen_US
dc.subjectsoil conservationen_US
dc.subjectcorn productivityen_US
dc.subjectcorn BMPsen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineNatural Resourcesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorZaimes, Georgeen_US
dc.contributor.chairGuertin, D. Phillipen_US
dc.contributor.chairLopes, Vicente L.en_US
dc.contributor.committeememberHawkins, Richard H.en_US
dc.contributor.committeememberZaimes, Georgeen_US
dc.contributor.committeememberWissler, Craigen_US
dc.identifier.proquest2648en_US
dc.identifier.oclc659749650en_US
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