Design for a sustainable research agroecosystem at the University of Illinois

Background/Question/Methods

As pressures to feed an ever growing world population increase, agriculture must develop sustainable agroecosystems that reconcile increased production with greater environmental protection.  In the spring of 2007 an interdisciplinary design workshop class developed a plan for a sustainable agroecosystem research farm at the University of Illinois. The goal was a plan for an education center where cutting-edge best management practices would be showcased for students, farmers, researchers, and residents of the Midwest. The hypothetical design would improve production sustainability on the farm while also improving environmental resource sustainability. The successful sustainable farm design would: provide all research needs (both plant and animal, including food); provide all energy needs; sequester C or at least be C neutral; treat all animal and human waste on site; control all runoff on site; and, cease the export of pesticides and nutrients from the site via surface waters.  The workshop used methodologies developed by the design arts (landscape architecture, architecture, and urban and regional planning) to help bridge the typical gap between basic scientific knowledge and its real world application.  To compare overall energy, carbon, hydrologic, and nutrient budgets between the hypothetical sustainable design and the existing status quo practices, a spreadsheet sustainability calculator was developed.

Results/Conclusions

Under the status quo model a total food surplus of 21.1 million lbs. was produced; while no energy for heat or electricity was produced on site.    Natural gas heating and electrical energy ran an annual deficit (270.6 billion BTUs).  All liquid fuel would be purchased, and embodied energy used in crop production would not be offset.  This resulted in an overall hypothetical negative energy balance of 292.5 billion BTUs.  Under the sustainable model corn grain production, corn silage, soy feed, and non-native hay acreages were reduced while oats, native prairie, haylage, rapeseed, miscanthus, and  switchgrass production were increased.  The food surplus was 12.4 million lbs. and the energy balance was a positive 23.9 billion BTUs.  Rapeseed production (750 acres) completely balanced the annual liquid biodiesel budget (≈ 1.4 billion BTUs), all building heat was provided, and embodied energy (used in crop production) was offset.  Thirty-five billion excess BTUs of electricity were produced using methane derived from animal waste and sold to the grid or diverted to the main campus.  With added pasture area and the application of no-till agriculture on 50% of the site, potential carbon sequestration exceeded total carbon emissions by 2,816 tons per year.