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Full-Text Articles in Physical Sciences and Mathematics

Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom Dec 2015

Simulating Management Effects On Crop Production, Tile Drainage, And Water Quality Using Rzwqm–Dssat, S. A. Saseendran, Liwang Ma, Robert W. Malone, Philip Heilman, Lajpat R. Ahuja, Ramesh S. Kanwar, Douglas L. Karlen, G. Hoogenboom

Douglas L Karlen

The objective of this study was to explore if more crop-specific plant growth modules can improve simulations of crop yields, and N in tile flow under different management practices compared with a generic plant growth module. We calibrated and evaluated the Root Zone Water Quality Model (RZWQM) with the Decision Support for Agrotechnology Transfer (DSSAT v3.5) plant growth modules (RZWQM–DSSAT) for simulating tillage (NT — no till, RT — ridge till, CP — chisel plow, and MP — moldboard plow), crop rotation {CC — continuous corn, and CS — corn (Zea mays L.)–soybean [Glycine max (L.) Merr.]}, and nitrogen (N) …


Rzwqm Simulation Of Long-Term Crop Production, Water And Nitrogen Balances In Northeast Iowa, L. Ma, Robert W. Malone, Philip Heilman, Douglas L. Karlen, Ramesh S. Kanwar, Cynthia A. Cambardella, S. A. Saseendran, Lajpat R. Ahuja Dec 2015

Rzwqm Simulation Of Long-Term Crop Production, Water And Nitrogen Balances In Northeast Iowa, L. Ma, Robert W. Malone, Philip Heilman, Douglas L. Karlen, Ramesh S. Kanwar, Cynthia A. Cambardella, S. A. Saseendran, Lajpat R. Ahuja

Douglas L Karlen

Agricultural system models are tools to represent and understand major processes and their interactions in agricultural systems. We used the Root Zone Water Quality Model (RZWQM) with 26 years of data from a study near Nashua, IA to evaluate year to year crop yield, water, and N balances. The model was calibrated using data from one 0.4 ha plot and evaluated by comparing simulated values with data from 29 of the 36 plots at the same research site (six were excluded). The dataset contains measured tile flow that varied considerably from plot to plot so we calibrated total tile flow …


Soil Quality In Relation To Forest Conversion To Perennial Or Annual Cropping In Southern Brazil, Elcio Liborio Balota, Ines Fumiko Ubukata Yada, Higo Furlan Amaral, Andre Shigueyoshi Nakatani, Mariangela Hungria, Richard Peter Dick, Mark S. Coyne Jul 2015

Soil Quality In Relation To Forest Conversion To Perennial Or Annual Cropping In Southern Brazil, Elcio Liborio Balota, Ines Fumiko Ubukata Yada, Higo Furlan Amaral, Andre Shigueyoshi Nakatani, Mariangela Hungria, Richard Peter Dick, Mark S. Coyne

Plant and Soil Sciences Faculty Publications

Many forested areas have been converted to intensive agricultural use to satisfy food, fiber, and forage production for a growing world population. There is great interest in evaluating forest conversion to cultivated land because this conversion adversely affects several soil properties. We examined soil microbial, physical, and chemical properties in an Oxisol (Latossolo Vermelho distrófico) of southern Brazil 24 years after forest conversion to a perennial crop with coffee or annual grain crops (maize and soybeans) in conventional tillage or no-tillage. One goal was to determine which soil quality parameters seemed most sensitive to change. A second goal …


Surface Runoff Characteristics From Claypan Soil In Southeastern Kansas Receiving Different Plant Nutrient Sources And Tillage, D. W. Sweeney, Philip Barnes, Gary Pierzynski Jan 2015

Surface Runoff Characteristics From Claypan Soil In Southeastern Kansas Receiving Different Plant Nutrient Sources And Tillage, D. W. Sweeney, Philip Barnes, Gary Pierzynski

Kansas Agricultural Experiment Station Research Reports

Preliminary results show that two-year average total nitrogen (N) runoff losses and ortho-phosphorus (P) and total P runoff losses in the second year were greater with N-based turkey litter/no-till applications than P-based turkey litter or fertilizer-only applications. Incorporation of turkey litter applied based on N requirements resulted in N and P losses that did not differ from losses from P-based or fertilizer-only treatments. Chemical and statistical analyses of third-year samples will allow for final results and interpretation.