Biomass Crops to Enhance Water Quality
Session Chair: Stephen F. John, Agricultural Watershed Institute
The introduction of dedicated biomass crops for renewable energy creates an opportunity to enhance water quality by strategically locating and managing these deep-rooted perennials on the Illinois agricultural landscape. This session will highlight projects currently underway that are designed to combine perennial biomass production with water quality and other environmental benefits and also support stronger rural economies. Where possible, water quality results from watershed-scale projects will be presented. Presenters will address such topics as: woody and herbaceous biomass crops well suited to areas subject to flooding or ponding; synergies and trade-offs between multiple objectives including biomass yield, water quality enhancement, and wildlife habitat; biomass production in saturated buffers managed to reduce nutrient losses from tile-drained cropland; sediment and nutrient reductions achievable with 10% to 20% perennial cover; and multifunctional cropping systems that mix annual and perennial crops for sustainable agricultural production and improved environmental outcomes.
1. Stephen F. John
Steve John is the co-founder and executive director of the Agricultural Watershed Institute, a nonprofit research organization based in Decatur, Illinois. AWI's Local Bioenergy Initiative is addressing the environmental benefits of perennial energy grasses. Prior to AWI's formation, Mr. John was an environmental planning consultant. From 1987 to 1995, he served on the Decatur City Council and was active in watershed management to protect Lake Decatur. He serves on the steering committees of the Green Land Blue Waters Consortium and the Illinois Biomass Working Group. He has a B.A. in Sociology from the University of Notre Dame.
Abstract: Experimental watershed projects as a research platform for co-production of cellulosic biomass and ecosystem services
In many Corn Belt watersheds, the percentage of total land area devoted to grassland is in the single digits. Much of the grass acreage in prime row crop areas is enrolled in the Conservation Reserve Program or other programs that generally prohibit harvesting biomass as a forage or bioenergy crop. A number of stakeholder-led projects around the U.S. are beginning to focus on perennial grasses grown for biomass and environmental benefits. The Upper Sangamon River Watershed in Central Illinois offers a case study of ongoing efforts to combine biomass production with water quality enhancement. A major question is how much nutrient and sediment load reduction is achievable through targeted conversion of a relatively small percentage of the landscape to perennial biomass crops, and at what cost? Biodiversity and wildlife habitat enhancement are additional goals in the Upper Sangamon watershed and other biomass projects. Such projects provide opportunities for environmental and agricultural scientists to engage with conservation professionals, agricultural producers, and other stakeholders for mutual benefit. Scientists can apply knowledge gained from plot research on the broader landscape and test models designed to address the challenge of balancing agricultural production and environmental outcomes. Mechanisms to compensate land managers for the value of ecosystem services, including but not limited to nutrient retention and carbon sequestration, may be an important factor in the economic viability of biomass crops. Expert-stakeholder collaboration in experimental watersheds can form a test bed for identifying agricultural policies and practices to optimize multiple benefits of cropping systems with significantly more perennial land cover.
2. Gayathri Gopalakrishnan
Dr. Gayathri Gopalakrishnan is an environmental scientist at Argonne National Laboratory. In the last eight years, she has been conducting research in phytoremediation, environmental systems analysis, renewable energy and sustainability. She received her Ph.D. from the University of Illinois at Urbana-Champaign in 2008.
Abstract: Designing multi-functional agricultural landscapes to meet food, energy and ecosystem goals
A sustainable landscape needs to balance disparate and competing objectives in order to meet environmental, economic and energy and food security goals. Pressures on the landscapes have intensified as a result of the focus on bioenergy production to mitigate greenhouse gas emissions and meet energy security demands. This research presents a framework for designing multi-functional, sustainable agricultural landscapes by using environmental liabilities such as marginal land and degraded water as resources for energy crop production. Results from spatial analyses at the regional scale indicate that sufficient biomass can be produced using this strategy to meet current US bioenergy mandates. This strategy is being implemented at a 15 acre experimental farm field in Illinois, where bioenergy crops are grown in contour strips adjacent to corn such that nutrients present in runoff and leachate from the traditional row-crop are reused by the bioenergy crops in the contour strips, thus providing environmental services and meeting economic needs of farmers.
3. Dan Jaynes
Dan Jaynes is a Research Soil Scientist at the USDA-Agricultural Research Service, National Laboratory for Agriculture and the Environment in Ames, IA and a Collaborating Professor in Agronomy at Iowa State University. He has studied the fate and transport of agrichemicals in the landscape for the past 25 years and authored 150+ scientific publications. Current areas of research include characterizing the impact of farming practices on nitrate losses to surface waters, investigating the spatiotemporal patterns of yield variations in corn and soybean fields, and developing new designs and management procedures for tile drainage to reduce nitrate losses to surface waters.
Abstract: Saturating riparian buffers in tile-drained landscapes
Riparian buffers are effective in removing nitrate moving to streams in shallow groundwater by a combination of plant uptake and denitrification. However, in the 17.4 million ha of drained land in the Midwest, much of the nitrate laden water leaching from row crop fields is routed directly through the buffers in subsurface drainage pipe, bypassing the buffer and emptying directly into surface waters. To more fully exploit the riparian buffers installed in tile-drained landscapes for nitrate removal, the hydrology between the tile drains and the buffer must to be reconnected. By intercepting tiles where they cross riparian buffers and diverting a fraction of the flow through lateral distribution tiles into the buffer, we propose to increase the buffers capacity for removing nitrate. An initial trial of this concept is being conducted in the Bear Creek watershed in central Iowa. Flow from a single field tile has been diverted into the shallow groundwater along 320 m of an existing 27-m wide riparian buffer. Initial measurements indicate that approximately 0.4 m3 of tile flow can be absorbed per meter of the buffer per day. Given the average nitrate concentration of tile drainage of 11 mg L-1 this is equivalent to diverting about 4.3 g of nitrate-N per m of buffer per day. Shallow ground water observations within the buffer indicate that all of the nitrate that enters the buffer is removed and does not enter Bear Creek. Thus, saturating 320 m of riparian buffer has prevented about 250 kg of nitrate-N per year from entering Bear Creek, greatly improving the performance of the buffer for removing nitrate in this tile-drained landscape.
Discussion Panel Members:
Dr. Stacy James has been employed by Prairie Rivers Network as a Water Resources Scientist since 2006. She contributes to Prairie Rivers' mission to protect Illinois' clean water by working to reduce the amount of urban and agricultural pollution entering streams. Before joining Prairie Rivers, she was a post-doc at the USGS Columbia Environmental Research Center in Missouri, where she conducted research on the effects of water pollution on amphibians.