Post on 13-Jul-2015
Biomass and the Environment: Soil and Water Impacts
David Mulla*Professor & Larson Chair for Soil &
Water ResourcesDept. Soil, Water & Climate
University of Minnesota*Coauthors for this talk include: David Pitt, Dept. Landscape Architecture, Carissa Shively-Slotterback, Humphrey School
of Public Affairs and Nicholas Jordan, Dept. Agronomy & Plant Genetics (all University of Minnesota)
Alternative Management Practices•Conservation Tillage:
• Chisel and disk tillage practices are replaced with a conservation tillage practice that leaves 30% residue at time of planting. Field cultivators are still used before planting.
•Stover Removal w/wo Cover Crops•Reduced Phosphorus Fertilizer Rates:
• P fertilizer rates are reduced by half.
•Cropland Conversion to Prairie Grass: • Biomass is harvested. Previous tile drainage systems remain intact.
•Cropland Conversion to Switchgrass: • Biomass is harvested. Previous tile drainage systems remain intact.• Switchgrass plantings in buffer strips is an option.
Methods Use SWAT (Soil Water Assessment Tool) to
analyze how changes in land management in Seven Mile Creek affect ecosystem services and biodiversity conservation
Compare the impact on ecosystem services & biodiversity from: – Current land use– Alternative land management and land use change
scenarios Results for each HRU are transferred to an
Excel spreadsheet and linked to an ArcGIS platform for real-time evaluation of GeoDesign scenarios by stakeholders
Stakeholder Rules of Thumb Increase landscape diversity Produce food/biofuel without harming
water quality or habitat Improve soil quality Consider feedstock transport distances Buffer waterways Improve wildlife habitat Match crop suitability to soil productivity
Performance Indicators
DischargeSediment lossPhosphorus lossHabitatCarbon sequestrationProfitability
Conclusions Novel GeoDesign process was developed Participants from different backgrounds shared
perspectives and worked collaboratively Stakeholders learned quickly, easily grasped
design concepts and used biophysical feedback indicators
Stakeholders incorporated clustering and spatial continuity into their landscape designs
Designs were not only profitable, but also exhibited improved water quality, carbon sequestration and terrestrial bird habitat