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Midwestern Management of Biomass for Energy, Soil and Water Conservation and Soil Health
Douglas L. Karlen, Larry Beeler, and Bruce E. DaleUSDA-ARS, USDA-NRCS, and Michigan State University
Presented at the 15th SWCS/SSSA Joint Symposium SWCS Annual Meeting – Lombard, Illinois
July 29, 2014
Midwest biomass: the past, present and future
Lessons learned regarding sustainable corn stover harvest
NRCS guidelines and programs available to biomass suppliers
Critical soil and water research needed for sustainable biomass supplies
Presentation Overview
Biomass is Not a New Midwestern Commodity
Native Americans Managed Prairie for Bison Grazing
From H.F. Reetz
Midwest Landscape -- 2014
Corn and soybean are dominant crops because of soil resources, climate and infra-structure
Production of these crops has been successful but ecosystem services have been disrupted
Growing demand for biomass for biofuel and/or bio-products creates opportunities to optimize cropping systems
Integrating food, feed and fuel production could improve productivity and ecosystem services
The Midwest – Current Status
Midwest Regional Roadmap www.swcs.org/roadmap)
Renewable energy is essential for human well-being
The rate of energy use (rate of doing work) strongly affects, even determines, national wealth and opportunities for human development
All rich societies use a lot of energy (~33% oil)
“Energy efficiency” is essential but insufficient in itself
Fossil energy use makes us rich today—what energy sources will make our children rich? Answer: fossil energy cannot, it will be gone in the next few decades….
Why renewable energy is crucial
Without it, how will the billions of poor people in the world ever access enough fossil energy to develop their potential? Answer: they cannot, it will be gone in the next few decades…
Globally, we must have renewable energy — lots of it in the next few decades
Why? Because of all forms of energy, liquid fuels are the most valuable and most problematic in terms of supply, price and price volatility
Why renewable energy is crucial
Although controversial, peak oil quite likely has already arrived
Only large scale, low cost, low carbon energy sources can reduce GHGs, provide energy security and long term wealth
Biofuels (liquid fuels from plant material) are not optional — we must have them — but they must also become much more sustainable
Corn stover
Miscanthus/Switchgrass
Oilseeds
Woody species
Midwest Biomass Resources
Midwest Regional Roadmap (www.swcs.org/roadmap)
Canola,PennycressCamelina
US-EPA and others identified corn stover as the most economical feedstock because of:
The extensive area on which corn is grown (planted on an average of 97,272,000 acres in 2011 – 2013)
The relatively high crop productivity (an average of 11.9 billion bushels of grain for those years)
Potential average stover production of 282 million tons per year based on a 0.5 harvest index
The potential to reduce crop residue management costs by harvesting a portion of the stover
BUT – stover is also important for soil health!
2013 winter erosion in Story County, Iowa
2013 corn production site in Green County, Wisconsin
Excessive Stover Harvest Can Result in:
Compaction & crusting
Degraded structure & aggregation
Water & wind erosion
Reduced plant growth
Impaired soil biology
Decreased yield
Reduced Soil Productivity
REAP/Regional Partnership Sites
Compiled 239 site-years of stover harvest dataEffects on subsequent grain and stover yieldsEffects on soil organic carbon (C) & aggregationEffects on microbial communityEffects on GHG emissions
Summarized in: BioEnergy Research, Vol. 2, 2014
Developed the Landscape Environmental Assessment Framework (LEAF) and other tools to:Estimate available residueQuantify economicsEnsure ecosystem service benefits are sustained
What Was Accomplished?
This involved ARS, DOE, university, and private industry partners
Utilized Multiple Harvest Technologies
University Park
Lincoln
Ames, Morris & St. Paul Florence Industry Collaborators
What Was Learned? Corn grain yields ranged from 5.0 to 14.3 Mg ha-1 (80
to 227 bu/acre)
Average grain yield response to stover harvest was minimal: 9.8, 10.1, and 10.1 Mg ha-1 (156, 160, and 160 bu/acre) for: No, moderate (3.9 Mg ha-1 or 1.7 tons/acre), or high removal
(7.2 Mg ha-1 or 3.2 tons/acre)
Sustainable stover harvest rates are site specific –averages are meaningless
Appropriate residue harvest may encourage Midwest producers to adopt no-till corn production practices
Other Lessons – Including Soil Health Compared to harvesting only grain – N, P, and K removal
are increased by at least 16, 2, and 18 kg Mg-1 of stover Minimum residue return projections for 35 studies were
6.38 ± 2.19 Mg stover ha-1 yr-1
For grain yields ≤ 11 Mg ha-1 (175 bu ac-1), ten years of stover harvest, even with no-tillage, resulted in reduced POM (particulate organic matter) accumulation
Low corn yields shifted the dry aggregate distribution toward smaller soil aggregates
Insufficient yields resulted in undesirable shifts in the microbial community
Overall, sustainable supplies of corn stover may be lower than initially projected because of weather-induced yield variability
Strategies to Ensure Sustainability
Encourage the entire biomass industry to understand the economic driver – limiting factor model
Strategies Continued Seek large, complementary, and beneficial changes:
we need food (feed) and fuel and sustainability andrural economic development and better social outcomes Living mulches Oilseeds
Double Cropping Growing cover crops (rye, triticale, brassicas) during the winter &
early spring on “dedicated” corn or soybean land: Does NOT require new land Increases sustainable corn stover harvest rate Provides addition biomass for biofuels, animal feed, etc Reframes the “food vs. fuel” debate
Holt, MI: May 5, 2005
Strategies Continued Continue to develop management tools such as the
Landscape Environmental Assessment Framework (LEAF) and self-regulating strategies to ensure sustainability
Re-diversify the Midwestern Landscape
Re-Diversification Requires the Right Question
We are asking: Can we impose a very large new demand for biofuels on the existing agricultural system without creating soil, water, or other problems?
We should be asking: Can we redesign U.S. agriculture to produce biofuels, food/feed, and environmental services? Would you enter the Indy 500 race driving a golf cart? Would you use a toothbrush to sweep the floor? Agriculture has changed before; it can change again Examine actual land uses: most land is used for animal feed
Therefore: co-produce animal feeds with biofuels and/or make much better use of pasture land
An Alfalfa Paradigm Shift
Goal – diversify landscape, provide feedstock,improve soil health, & protect water quality
Alfalfa Leaf Protein Collection & Extraction
Create market-pull for perennials by starting with a familiar crop
NRCS & FSA Biomass Perspectives
Energy crops include: Woody species – cottonwood, hybrid poplas, silver maple,
black locust, sweetgum, eucalyptus, sycamore and willow
Hebaceous perennials – switchgrass, bluestem, reed canarygrass, wheatgrass, miscanthus
Residues from annual crops – corn, sorghum and soybean
Biomass crops should be grown in ways that ensure environmental and economic sustainability, with minimal or no adverse effects on natural ecosystems, biodiversity and with minimal reliance on any single crop
NRCS & FSA Biomass Production Programs
Conservation Stewardship Program (CSP) Environmental Quality Incentives Program (EQIP) Conservation Innovation Grants (CIG) Regional Conservation Partnership Program (RCPP) Conservation Reserve Program (CRP) Biomass Crop Assistance Program (BCAP)
Establishment payments for 50% of the costs for establishing a new, perennial energy crop
Maintenance payments until the crop matures (up to: 5 years for herbaceous crops, 15 years for woody crops)
Retrieval payments (matching) for mitigating the cost of harvesting and transporting agricultural and forestry residues to the end-use facility
Natural Resource Defense Council (NRDC) Perspectives
Bioenergy made from sustainably harvested cover crops has the potential to build the country’s renewable energy portfolio while conserving resources and increasing farmers’ income.
Creation of local biomass markets and greater access to incentives could significantly increase adoption rates for cover crops
Biomass potential and Trade-Offs Cover crops producing 2 to 5 tons/acre could provide 44 to 110
million tons of biomass per year if 10% of the nation’s 220 million acres were planted and harvested
If incentives resulted in 30% adoption of cover crops, this feedstock could provide 10 to 36 billion gallons of ethanol.
The primary concern regarding cover crops is their potential negative effects on the yield of subsequent primary crops.
Research Needs Effective and efficient strategies for incorporating cover
crops in stover harvest systems No-tillage technologies that incorporate site-specific,
variable-rate seeding Innovative harvest methods and new uses for perennial
crops Improved herbaceous and woody biomass cultivars with
higher yield potential & better biofuel/bio-product characteristics
Quantify habitat impact of harvesting biomass Quantify runoff, nutrient, and pesticide losses associated
with biomass harvest Develop options and practices that enhance the value of
marginal lands
Summary & ConclusionsRenewable energy is essential for human well-being
Biofuels (liquid fuels from plant material) are not optional — we must have them — but they must be truly sustainable – economically, environmentally, & socially
Finally, borrowing from the Wizard of Oz – “If we only had a brain” we conclude that any perceived food vs. fuel conflict can be solved without having a negative impact on soil, water, or air resources by simply using our heads!
Developing Sustainable Stover Harvest Strategies is Just a First Step Toward Solving Multiple Energy and Ecosystem Challenges
Any Questions?