how much carbon can be sequestered by organic-based cropping systems...
TRANSCRIPT
How much Carbon Can be How much Carbon Can be Sequestered by OrganicSequestered by Organic--based based Cropping Systems in MI Soils?Cropping Systems in MI Soils?
Senthil Subramanian, Sasha Kravchenko, Kurt Thelen,
Alvin SmuckerCSS, MSU
• Soil organic systems have a potential to increase C sequestration by soils.
• Reduction in atmospheric CO2 contributes an important component to the effort of reducing global warming.
• Providing organic producers with extra benefits from carbon credit trading?
Introduction
Objectives:
• To compare the quantities of total C in– Organic management with a winter leguminous
cover crop and– Conventional (chisel plow) management with
chemical inputs– No-till management with chemical inputs
• To identify topographical and soil conditions that lead to most rapid and effective C sequestration in organic management.
after long-term (>16 years) implementation.
Study Site:
Long Term Ecological Research Plots at KBS,MI
Treatments studied:- Tillage + chemical inputs (T1) - No-till + chemical inputs (T2)- Certified Organic: Tillage + Cover crops (T4)
Crop Rotation:Main crops: corn-soybean-wheatCover crops: hairy vetch or red clover
T2R5
T1R5 T4R5
T1R1 T2R2 T2R3
T4R3 T2R4
T4R2 T1R4T5R1
T5R2 T4R4
T4R1 T1R2
T2R1 T5R3
T1R3 T5R4
T1R6
T4R6
T5R6 T2R6
Lay out of the LTER Main site
T2R5
T1R5 T4R5
T1R1 T2R2 T2R3
T4R3 T2R4
T4R2 T1R4
T4R4
T4R1 T1R2
T2R1
T1R3
T1R6
T4R6
T2R6
Layout of the experimental site along with soil sampling locations and elevation
map
Results: Total C and N in the three studied management systems after 17 years of experiment
T1 T2 T4 T1 T2 T4
Results: Total C in the studied managements at topographical uphills and depressions
Results: Total C in conventional and organic managements at topographical uphills and depressions
Organic – T4In terms of increasing soil C organic management with cover crops in depressions worked the best.
Results: Total C in the studied managements at topographical uphills and depressions
Results: Total C in conventional and organic managements at topographical uphills and depressions
Results: Total C in the studied managements at topographical uphills and depressions
Results: Total C in conventional and organic managements at topographical uphills and depressions
ConclusionsOrganic system with cover crops was found to be as efficient in increasing soil C and N contents as conventional no-till management.Organic system with cover crops had significantly higher C and N levels than conventional chisel-plow management across the entire landscape.On average, each year the organic management with cover crops was adding 0.2 Mg/acre more of C to the top 30 cm of soil as compared to the conventional chisel plow.
ConclusionsHowever the gains in C due to organic management with cover crops were much more pronounced at the lower topography as compared to slopes and summits. At uphill positions each year the organic management with cover crops was adding 0.13 Mg/acre more of C to the top 30 cm of soil as compared to the conventional chisel plow.At depression positions each year the organic management with cover crops was adding 0.23 Mg/acre more of C to the top 30 cm of soil as compared to the conventional chisel plow.
Thank youThank you……