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Comparison of Biofuel Systems (COBS)

This project seeks to identify and develop cropping systems that produce large quantities of biofuel feedstocks while protecting soil and water resources and increasing biodiversity on the Iowa landscape. Treatments in the COBS experiment include a conventional corn-soybean cash grain system; continuous corn grown for grain and stover, with and without a winter cover crop; a mixture of perennial prairie plants fertilized for high biomass production; and a highly diverse, unfertilized mixture of prairie plants, which serves as a benchmark for understanding the functional characteristics of a native plant community. Our central premise is that cropping systems designed to produce large amounts of biomass, with high net energy return, can simultaneously create significant environmental benefits. Our working hypotheses are that (1) cover crops can reduce nutrient losses from corn production systems, (2) diverse mixtures of perennial plants can produce nearly as much biomass as conventionally managed corn, but with greater economic and energetic efficiency; and (3) diverse plant mixtures used for feedstock production can emit fewer pollutants to drainage water, sequester more carbon, and reduce greenhouse gas emissions relative to corn- and soybean-based cropping systems. We will compare systems by measuring plant productivity, resource use efficiency, nutrient dynamics, soil organic matter maintenance and production, carbon sequestration, CO2 emissions, and drainage water quantity and quality. Direct comparisons within a spectrum of cropping systems will lead to informed analyses of the advantages and disadvantages of each system.

Principal Investigators
Cruse, Richard
Office:
3202 Agronomy 716 Farm House Ln
Phone:
(515) 294-7850
Email:
rmc@iastate.edu
Distinguished Professor
Horton, Robert
Office:
2543 Agronomy 716 Farm House Ln
Phone:
(515) 294-7843
Email:
rhorton@iastate.edu
Professor (Emeritus)
Henry A. Wallace Endowed Chair for Sustainable Agriculture
Liebman, Matt
Office:
1401 Agronomy 716 Farm House Ln
Phone:
(515) 294-7486
Email:
mliebman@iastate.edu
Professor
President-Elect, Soil Science Society of America
Thompson, Michael
Office:
2503 Agronomy 716 Farm House Ln
Phone:
(515) 294-2415
Email:
mlthomps@iastate.edu