U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Malone, Robert

                                                         - *Rob*item
                                            Ma, Liwangitem
                                            Karlen, Douglasitem
                                            Meade, Terryitem
                                            Meek, Daviditem
                                            Heilman, Philip

                                                         - *Phil*item
                                            KANWAR, R - IA STATE UNIVERSITYitem
                                            Hatfield, Jerry
  Submitted to: National Water Quality Monitoring Council
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 5/11/2006
                                    Publication  Date: N/A
                                    Citation: N/AInterpretive Summary:
                                Technical Abstract: Crop yield and nitrate nitrogen losses through subsurface drainage are affected by multiple climatic and management variables, however the interactive affect of these variables is not well understood.  Simple equations that predict nitrate loading and crop yield as a function of important variables may improve our understanding of agricultural systems.  Therefore, we developed multivariate polynomial regression equations to predict crop yield, nitrate concentration, drainage volume, and nitrate loading from a corn and soybean rotation in response to rainfall amount, N source, N rate, and timing of N application in northeastern Iowa.  The regression equations described over 85% loading, 69% drainage, 60% yield, and 48% nitrate concentration variation.  The regression equations were then used to analyze nitrate leaching and crop yield under a variety of N management and climate scenarios.  The regression equations improve our understanding of variable interactions on nitrate leaching, offer a simple method to quantify potential N losses from Midwestern corn-soybean rotations, and are a step toward development of easy to use N management tools.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov