Managing Global Resources for a Secure Future

2017 Annual Meeting | Oct. 22-25 | Tampa, FL

106884 Cover Crop Termination Date Effects on Greenhouse Gas Fluxes in Rainfed and Irrigated No-till Corn.

Poster Number 612

See more from this Division: SSSA Division: Soil and Water Management and Conservation
See more from this Session: Managing Soils and Crops with Cover Crops Poster

Wednesday, October 25, 2017
Tampa Convention Center, East Exhibit Hall

Sabrina Ruis, University of Nebraska - Lincoln, Lincoln, NE, Humberto Blanco-Canqui, Dept of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, Paul Jasa, University of Nebraska-Lincoln, Lincoln, NE and Richard B Ferguson, Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE
Abstract:
Cover crops (CC) can increase SOC and scavenging of N, particularly when CC are grown for longer periods. This increased storage of C and N with increased CC growing time could alter gaseous emissions of C and N (CO2, N2O, and CH4) and related soil properties. Thus, the objective of this research was to assess soil greenhouse gas fluxes, and related soil properties of temperature, water content, soil aggregation, and air-filled porosity changes throughout the year under no CC and early or late terminated CC in rainfed and irrigated no-till continuous corn beginning after three years of CC. Soil gas fluxes, temperature, and water content were monitored biweekly from March through May and monthly from June through February. Soil porosity and soil aggregation were determined seasonally on soil samples from 0 to 5 cm depth. Both early and late terminated CC did not affect N2O or CH4 fluxes. Early terminated CC increased CO2 fluxes less than late termination, likely due to influences of plant respiration. Soil water content was less under late terminated CC compared to no CC; however, soil aggregation increased under late terminated CC compared to control. A comparison of cumulative CO2 fluxes with CC biomass showed that these two parameters are similar in C level, which suggests CO2 fluxes from the soil did not increase under CC. Overall, it appears that while CC may improve some soil properties, greenhouse gases are generally not affected by CC.

See more from this Division: SSSA Division: Soil and Water Management and Conservation
See more from this Session: Managing Soils and Crops with Cover Crops Poster