Rapid Changes in Soil Carbon and Structural Properties Due to Stover Removal from No-Till Corn Plots

Journal Article · Thu Jun 01 04:00:00 EDT 2006 · Soil Science

DOI:https://doi.org/10.1097/01.ss.0000209364.85816.1b· OSTI ID:885471

Blanco-Canqui, H; Lal, Rattan; Post, W M; Izaurralde, R Cesar C; Owens, L B

Harvesting corn (Zea mays L.) stover for producing ethanol may be beneficial to palliate the dependence on fossil fuels and reduce CO2 emissions to the atmosphere, but stover harvesting may deplete soil organic carbon (SOC) and degrade soil structure. We investigated the impacts of variable rates of stover removal from no-till (NT) continuous corn systems on SOC and soil structural properties after 1 year of stover removal in three soils in Ohio: Rayne silt loam (fine-loamy, mixed, active, mesic Typic Hapludults) at Coshocton, Hoytville clay loam (fine, illitic, mesic Mollic Epiaqualfs) at Hoytville, and Celina silt loam (fine, mixed, active, mesic Aquic Hapludalfs) at South Charleston. This study also assessed relationships between SOC and soil structural properties as affected by stover management. Six stover treatments that consisted of removing 100, 75, 50, 25, and 0, and adding 100% of corn stover corresponding to 0 (T0), 1.25 (T1.25), 2.50 (T2.5), 3.75 (T3.75), 5.00 (T5), and 10.00 (T10) Mg haj1 of stover, respectively, were studied for their total SOC concentration, bulk density (>b), aggregate stability, and tensile strength (TS) of aggregates. Effects of stover removal on soil properties were rapid and significant in the 0- to 5-cm depth, although the magnitude of changes differed among soils after only 1 year of stover removal. The SOC concentration declined with increase in removal rates in silt loams but not in clay loam soils. It decreased by 39% at Coshocton and 30% at Charleston within 1 year of complete stover removal. At the same sites, macroaggregates contained 10% to 45% more SOC than microaggregates. Stover removal reduced 94.75-mm macroaggregates and increased microaggregates (P G 0.01). Mean weight diameter (MWD) and TS of aggregates in soils without stover (T0) were 1.7 and 3.3 times lower than those in soils with normal stover treatments (T5) across sites. The SOC concentration was negatively correlated with >b and positively with MWD and LogTS. Stover removal at rates as low as 1.25 Mg haj1 reduced SOC and degraded soil structure even within 1 year, but further monitoring is needed to establish threshold levels of stover removal in relation to changes in soil quality.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 885471
• Report Number(s): PNNL-SA-50742; KP1202020
• Journal Information: Soil Science, Journal Name: Soil Science Journal Issue: 6 Vol. 171; ISSN SOSCAK; ISSN 0038-075X
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
29 ENERGY PLANNING, POLICY, AND ECONOMY
AGRICULTURAL WASTES
BULK DENSITY
CARBON
CLAYS
ETHANOL
FOSSIL FUELS
HARVESTING
LOAM
MAIZE
MANAGEMENT
MONITORING
REMOVAL
SILT
SOILS
STABILITY
Stover removal
no-till
bulk density
soil organic carbon
TENSILE PROPERTIES