$221,000 is from the trust fund to the Board of Regents of the University of Minnesota to determine how fertilization and irrigation impact yields of grass monoculture and high diversity prairie biofuel crops, their storage of soil carbon, and susceptibility to invasion by exotic species. This appropriation is available until June 30, 2013, by which time the project must be completed and final products delivered.
Click on "Final Report" under "Project Details".
Click on "Final Report" under "Project Details".
Perennial grasslands have the potential to provide Minnesota with locally grown energy sources that reduce greenhouse gas emissions, improve water quality, and provide other important benefits. However, much remains unknown about how these crops will be impacted by factors such as climate change and invasive species. Through this appropriation, researchers at the University of Minnesota's Cedar Creek Ecosystem Science Reserve will study how irrigation, fertilization, and climate warming impact perennial grassland biofuel crops in terms of yield, carbon sequestration, plant biodiversity, water quality, and susceptibility to invasive species. Findings will be used to develop methods for optimizing biofuel production, carbon storage, and habitat restoration.
OVERALL PROJECT OUTCOME AND RESULTS
Minnesota's perennial grasslands produce considerable biomass that could become a valuable resource for producing renewable energy. How might Minnesota's capacity to produce biomass for biofuels be impacted by climate change and anticipated mitigation practices? We explored the impacts of warming, fertilization, and irrigation on biomass production at the Cedar Creek Ecosystem Science Reserve.
Our major overall finding is that high diversity mixtures of prairie perennials provided the best combination of biomass production, invasion resistance, carbon storage in soil, and response to climate warming of all the biomass crops we tested.
Specific findings from the Climate Experiment include:
- Compared to low diversity mixtures of prairie plant species, high diversity mixtures produced much more biomass when experiencing normal weather, were more resilient to the stress of warming, and had their biomass production increase the most from warming.
- High diversity mixes enhanced ecosystem services more than low diversity mixes by sequestering more carbon in soils and being less prone to invasion by non-native species.
- Warming inhibited seed establishment. This could reduce invasions by non-native species, but might threaten establishment of native prairie restorations.
The Fertilization & Irrigation Experiment found:
- Fertilization had similar impacts across all species mixtures.
- Moderate fertilization and irrigation increased productivity, with the largest effects in the Panicum, Panicum+Grasses, and High Diversity plots.
Overall findings on plant invasion showed:
- Invasion is inhibited by higher diversity species mixtures.
- A potential biofuel crop, Miscanthus (as a sterile hybrid), was ineffective at producing biomass in central Minnesota, at least on sandy, drier soils. It had detectable, but moderate invasion into native prairies.
This research has been documented in one publication. Two manuscripts have been submitted and are either in review or under revision. Another manuscript is in preparation. We anticipate additional publications will follow. In 2012, the education programming Cedar Creek reached 6,619 users, including K-12 students, teachers, and the general public.
PROJECT RESULTS USE AND DISSEMINATION
The data from these studies will be included in Cedar Creek's database and made publicly available on the Cedar Creek website. Researchers around the world access and use the data on this site for diverse ecological analyses in many research areas including, among others, biodiversity, invasion, and climate change studies.
The results of these studies are integrated into the educational programming and outreach at Cedar Creek. In 2012, 1,777 K-12 students participated in on-site programs. 1,062 K-12 students participated in off-site programs. Furthermore, 120 K-12 teachers participated in professional development opportunities at Cedar Creek and in their schools. At the university level, 845 students and faculty have made use of Cedar Creek programs, courses, meetings, and workshops both on and off-site. There have been 1,070 visitors to the experimental sites where this study took place.
One journal article that documents findings from this study has been published. See:
Isbell, F., 2013, Nutrient enrichment, biodiversity loss, and consequent declines in ecosystem productivity, PNAS, 110: 29.
A second publication by Heather Whittington is under revision in Oecologia and a third has been submitted to Functional Biology. Jane Cowles has a fourth article in preparation. We anticipate additional publications will result from this work.