1 / 33

Balancing Biomass for Bioenergy and Conserving the Soil Resource

Balancing Biomass for Bioenergy and Conserving the Soil Resource. Jane Johnson USDA-ARS- North Central Soil Conservation Research Laboratory. Introduction. Energy paradigm is changing from petroleum to mixed renewable Sufficient energy available, but in diffuse form

sunila
Download Presentation

Balancing Biomass for Bioenergy and Conserving the Soil Resource

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Balancing Biomass for Bioenergy and Conserving the Soil Resource Jane Johnson USDA-ARS- North Central Soil Conservation Research Laboratory

  2. Introduction • Energy paradigm is changing from petroleum to mixed renewable • Sufficient energy available, but in diffuse form • Can we be sustainable or at least minimize environmental footprint? • Can we balance food, feed, fiber and fuel? USDA-ARS

  3. Outline • Background • Discuss roles of non-grain biomass • Constraints for harvest rates • Examples • Summary USDA-ARS

  4. NRCS plant material center Cellulosic biomass USDA-ARS

  5. Interest in biomass for bioenergy • Cellulosic ethanol – sugar platform • Thermochemical – controlled combustion • Gasification • Dimethylether (DME) • Replace natural gas • Pyrolysis Bio oil, bio char, biogas • Other bio-based products USDA-ARS

  6. Biomass for bioenergy Agriculture – 998 million tons • Perennial energy crops – 377 million tons • “Wastes” – 87 million tons • Grain – 87 million tons • Crop residues – 428 million tons • Corn stover – 256 million tons Forestry – 368 million tons (projected estimates; Billion Ton Report, Perlack et al 2005) USDA-ARS

  7. Biomass harvest • Benefits • Renewable • Domestic • Reduces release of fossil CO2 • Additional farm commodity • Risks • Decreased surface residues • Increased erosion • Off-site nutrient and sediments • Decreased SOM • Decreased productivity • Other – loss of winter cover, habitat USDA-ARS

  8. Primary roles of non-grain biomass • Protect the soil from erosion USDA-ARS

  9. Tillage Wind Water LaPorte, IN 2004 Wakeeney, KS L. Kucerik, 2004 http://www.umanitoba.ca MN, D. Reicosky Morris, MN 2003 USDA-NRCS USDA-ARS

  10. Primary roles of crop biomass • Protect the soil from erosion • Provide C and other organic inputs to support the below ground ecosystem USDA-ARS

  11. USDA-ARS

  12. Primary roles of crop biomass • Protect the soil from erosion • Provide C and other organic inputs to support the below ground ecosystem • Build and maintain soil organic matter/soil organic carbon USDA-ARS

  13. Biomass management for Carbon (C) storage • Storing C in soil – building humus • Nutrient cycling • Water holding capacity • Improve soil aggregation • Maintain soil productivity • Remove CO2 from atmosphere USDA-ARS

  14. C Inputs Crop above ground biomass Crop root and their exudates Manure Biomass management for C storageC inputs > C outputs = increased SOC • C Outputs • Respired C • Erosion • Tillage • Leaching • Harvest USDA-ARS

  15. USDA-ARS

  16. “The need to maintain soil productivity should be our first consideration and only, once this criterion has been met, should crop biomass be removed for alternative purposes.” William (Bill) Larson, 1979 USDA-ARS

  17. Minimum biomass inputs depends on • Precipitation and temperature • Crop • Crop rotation • Tillage • Nutrient management • Additional inputs • Limiting constraint (erosion or carbon) USDA-ARS

  18. USDA-ARS Renewable Energy Assessment Project (REAP) Team Locations USDA-ARS

  19. REAP goals • Determine how much biomass needs to stay on the land to protect soil resource • Compare short- and long-term economics of using biomass feedstock and soil organic input • Provide recommendations and guidelines for sustainable biomass harvest USDA-ARS

  20. How much biomass needs to stay in the field? • Prevent erosion • Sustain belowground ecosystem • Build soil organic matter • Sequester C • Maintain productivity USDA-ARS

  21. Erosion Reduces productivity Degrades soil Degrades water quality Amount as % surface cover Soil organic matter Reduces productivity Reduces water holding capacity Degrades soil Contributed to increased atm CO2 Total inputs Constraints USDA-ARS

  22. USDA-ARS

  23. Minimum inputs estimated by a simple linear relationship • y is change in soil organic carbon change • x is the amount of C (or biomass) input annually Larson et al., 1972; Paustian et al., 1997; Follett et al., 2005; Johnson et al., 2006 USDA-ARS

  24. USDA-ARS

  25. USDA-ARS

  26. Example, assumes conservation tillage and continuous corn USDA-ARS

  27. Wilhelm et al., 2007,AJ USDA-ARS

  28. USDA-ARS Wilhelm et al, 2007 AJ

  29. Products: • Guidelines for crop and soil management to ensure sustainable harvest • Predictive tools for crop biomass harvest • Tools to assess short and long-term trade-offs (environmental and economic) Outcome: • Biomass energy industry based on sustainable management practices. USDA-ARS

  30. Current projects • Biomass removal study • Tillage: • No Till (Established 1995) • No Till (Established 2005) • Chisel Plow, spring disk • Removal rates: 0, 50, 75 and 100% of rows • Monitor: biomass produced, returned, soil carbon (0-100 cm), yield USDA-ARS

  31. Carbon Crop Study Established 2000, modified 2007 No tillage USDA-ARS

  32. Related issues • No perfect solution • Fossil fuel – finite, huge environmental footprint • Water to grow crop • Water for conversion – energy platform dependent • Off-site impacts of nutrients/pesticides • Habitat USDA-ARS

  33. Its about the future: finding balance USDA-ARS

More Related