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
 Agricultural Systems Research: Sidney, MT
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    NPARL
                        NPARL
                                    Pest Management Research
                                    Grasshoppers: Their Biology, Identification and Management:Search small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Plains Area Sidney, Montana Northern Plains Agricultural Research Laboratory Agricultural Systems Research 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
                                            Sainju, Upendraitem
                                            Jabro, Jalal

                                                         - *Jay*item
                                            Stevens, William

                                                         - *Bart*
  Submitted to: Proceedings of the Workshop on Agricultural Air Quality: State of the Science  
                                    Publication Type: Proceedings
                                    Publication Acceptance Date: 3/31/2006
                                    Publication  Date: 6/5/2006
                                    Citation: Sainju, U.M., Jabro, J.D., Stevens, W.B. 2006. Soil carbon dioxide emission as influenced by irrigation, tillage, cropping system, and nitrogen fertilization. Workshop on Agricultural Air Quality. pp. 1086-1098.Interpretive Summary: Global warming due to increased concentration of greenhouse gases, such as carbon dioxide (CO2), in the atmosphere is a major concern. Agricultural practices contribute about 25% of total anthropogenic emissions. Soil can act as both source and sink of atmospheric CO2. The CO2 fixed in plant biomass through photosynthesis can be stored in the soil as organic C by converting plant residue into soil organic matter after the residue is returned to the soil. On the other hand, management practices, such as tillage, can increase CO2 emission from the soil by disrupting soil aggregates, increasing aeration, incorporating plant residue, and oxidizing soil organic C. Respiration by plant roots and soil microflora and fauna also contribute a major portion of CO2 emission from the soil. The CO2 emission from the soil to the atmosphere is the primary mechanism of C loss from the soil and provides an early indication of C sequestration in the soil when changes in soil organic C due to management practices are not detectable within a short period.

An experiment was set up in Nesson Valley in western North Dakota in 2005 to examine the effects of irrigation, tillage, crop rotation, and nitrogen fertilization on soil CO2 emission. Irrigation increased CO2 flux by 27% compared with non-irrigation by increasing soil water content during dry periods. Similarly, tillage increased CO2 flux by 58% compared with non-tillage by increasing soil temperature. The CO2 flux was 1.5 to 2.5-fold greater in tilled than in non-tilled treatments following heavy rain or irrigation. Crop rotation and nitrogen fertilization had limited to no effects on CO2 flux. The CO2 flux in undisturbed alfalfa and grasses treatment was similar to that in no-tilled crops. Tillage followed by heavy rain or irrigation during the crop growing season drastically increased CO2 flux in the coarse-textured soil previously managed under Conservation Reserve Program (CRP) planting for more than 20 yr.
                                Technical Abstract: Soil and crop management practices can influence CO2 emission from crop and grasslands and therefore on global warming. We examined the effects of two irrigation systems (irrigated vs. non-irrigated) and six management practices [no-till malt barley (Hordeum vulgaris L.) with 67 or 134 kg N ha-1 (NTBFN), no-till malt-barley with 0 kg N ha-1 (NTBON), conventional-till malt barley with 67 or 134 kg N ha-1 (CTBFN), conventional-till malt barley with 0 kg N ha-1 (CTBON), no-till pea (Pisum sativum L.) with 0 kg N ha-1 (NTPON), and undisturbed alfalfa (Medicago sativa L.) and grasses with 0 kg N ha-1 (UAGON)] on soil surface CO2 flux and soil temperature and water content at the 0 to 15 cm depth. Weekly CO2 flux, soil temperature, and soil water content were monitored during the crop growing season from May to November 2005 in Lihen sandy loam (sandy, mixed, frigid, Entic Haplustolls) in western North Dakota. Irrigation increased CO2 flux by 27% compared with non-irrigation by increasing soil water content during dry periods. Similarly, tillage increased CO2 flux by 58% compared with non-tillage by increasing soil temperature. The CO2 flux was 1.5 to 2.5-fold greater in tilled than in non-tilled treatments following heavy rain or irrigation. Nitrogen fertilization increased CO2 flux compared with no N fertilization in 2 out of 17 measurements while cropping system did not influence CO2 flux. The CO2 flux in undisturbed alfalfa and grasses was similar to that in no-tilled crops. The CO2 flux was linearly related with soil temperature and daily average air temperature at the time of CO2 measurement. Tillage followed by heavy rain or irrigation during the crop growing season drastically increased CO2 flux in the coarse-textured soil previously managed under Conservation Reserve Program (CRP) planting for more than 20 yr.


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