Cultivating Change in the Academy: 50+ Stories from the Digital Frontlines at the University of Minnesota in 2012

Ebook published independently by University of Minnesota authors who presented at the 2012 Academic Technology Showcase.This collection of 50+ chapters showcases a sampling of academic technology projects underway across the University of Minnesota, projects that we hope inspire other faculty and staff to consider, utilize, or perhaps even develop new solutions that have the potential to make their efforts more responsive, nimble, efficient, effective, and far-reaching. Our hope is to stimulate discussion about what’s possible as well as generate new vision and academic technology direction. The work underway is most certainly innovative, imaginative, creative, collaborative, and dynamic. This collection of innovative stories is a reminder that we are a collection of living people whose Land Grant values and ideas shape who we serve, what we do, and how we do it. Many of these projects engage others in discourse with the academy: obtaining opinion or feedback, taking the community pulse, allowing for an extended discourse, and engaging citizens in important issues. What better time to share 50+ stories about cultivating change than in 2012 – the 150th anniversary of the founding of the Land Grant Mission

Limited potential for terrestrial carbon sequestration to offset fossil-fuel emissions in the upper midwestern US

Many carbon dioxide (CO2) emission-reduction strategies currently under consideration rely on terrestrial carbon (C) sequestration to offset substantial proportions of CO2 emissions. We estimated C sequestration rates and potential land areas for a diverse array of land-cover changes in the Upper Midwest of the US, a “best case” region for this study because of its relatively modest CO2 emissions and the large areas of cropland potentially available for conversion. We then developed scenarios that apply some of the most widespread mitigation strategies to the region: the first, which aimed to offset 29% of regional CO2 emissions, required the unrealistic loss of two-thirds of working cropland; the second, which estimated the emission offset attainable by conversion of 10% of harvested croplands (5.8% of the US total), resulted in < 5% CO2 emissions reduction for the region (<1.1% of total US emissions). There is limited capacity for terrestrial C sequestration, so strategies should aim to directly reduce CO2 emissions to mitigate rising atmospheric CO2 concentrations

Distribution and Uptake Dynamics of Mercury in Leaves of Common Deciduous Tree Species in Minnesota, U.S.A.

A sequential extraction technique for compartmentalizing mercury (Hg) in leaves was developed based on a water extraction of Hg from the leaf surface followed by a solvent extraction of the cuticle. The bulk of leaf Hg was found in the tissue compartment (90–96%) with lesser amounts in the surface and cuticle compartments. Total leaf concentrations of Hg varied among species and was most closely correlated with the number of stomates per sample, supporting the hypothesis that stomatal uptake of atmospheric Hg (most likely Hg⁰) is a potential uptake pathway. Mercury concentrations in leaves were monitored from emergence to senescence and showed a strong positive correlation with leaf age. Leaves accumulated Hg throughout the growing season; the highest uptake rates coincided with periods of high photosynthetic activity. Concentrations of Hg in leaf tissue increased steadily throughout the season, but no such trends were observed for surficial or cuticular accumulation. Factors affecting the variability of Hg in leaves were analyzed to improve protocols for the potential use of leaves as passive monitors of atmospheric Hg. Results show that total leaf Hg concentrations are affected by leaf age and leaf placement in the crown

Yellow Perch (Perca flavescens) Mercury Unaffected by Wildland Fires in Northern Minnesota

Abstract Wildland fire can alter mercury (Hg) cycling on land and in adjacent aquatic environments. In addition to enhancing local atmospheric Hg redeposition, fire can influence terrestrial movement of Hg and other elements into lakes via runoff from burned upland soil. However, the impact of fire on water quality and the accumulation of Hg in fish remain equivocal. We investigated the effects of fire-specifically, a low-severity prescribed fire and moderate-severity wildfire-on youngof-the-year yellow perch (Perca flavescens) and lake chemistry in a small remote watershed in the Boundary Waters Canoe Area Wilderness in northeastern Minnesota. We used a paired watershed approach: the fire-affected watershed was compared with an adjacent, unimpacted (reference) watershed. Prior to fire, upland organic horizons in the two study watersheds contained 1549 mg Hg m −2 on average. Despite a 19% decrease in upland organic horizon Hg stocks due to the moderate severity wildfire fire, fish Hg accumulation and lake productivity were not affected by fire in subsequent years. Instead, climate and lake water levels were the strongest predictors of lake chemistry and fish responses in our study lakes over 9 yr. Our results suggest that low-to moderate-severity wildland fire does not alter lake productivity or Hg accumulation in young-of-the-year yellow perch in these small, shallow lakes in the northern deciduous and boreal forest region

Toward Bioremediation of Methylmercury Using Silica Encapsulated Escherichia coli Harboring the mer Operon.

Mercury is a highly toxic heavy metal and the ability of the neurotoxin methylmercury to biomagnify in the food chain is a serious concern for both public and environmental health globally. Because thousands of tons of mercury are released into the environment each year, remediation strategies are urgently needed and prompted this study. To facilitate remediation of both organic and inorganic forms of mercury, Escherichia coli was engineered to harbor a subset of genes (merRTPAB) from the mercury resistance operon. Protein products of the mer operon enable transport of mercury into the cell, cleavage of organic C-Hg bonds, and subsequent reduction of ionic mercury to the less toxic elemental form, Hg(0). E. coli containing merRTPAB was then encapsulated in silica beads resulting in a biological-based filtration material. Performing encapsulation in aerated mineral oil yielded silica beads that were smooth, spherical, and similar in diameter. Following encapsulation, E. coli containing merRTPAB retained the ability to degrade methylmercury and performed similarly to non-encapsulated cells. Due to the versatility of both the engineered mercury resistant strain and silica bead technology, this study provides a strong foundation for use of the resulting biological-based filtration material for methylmercury remediation

Long-Term Experimental Manipulation of Atmospheric Sulfate Deposition to a Peatland: Response of Methylmercury and Related Solute Export in Streamwater

Changes in sulfate (SO42–) deposition have been linked to changes in mercury (Hg) methylation in peatlands and water quality in freshwater catchments. There is little empirical evidence, however, of how quickly methyl-Hg (MeHg, a bioaccumulative neurotoxin) export from catchments might change with declining SO42– deposition. Here, we present responses in total Hg (THg), MeHg, total organic carbon, pH, and SO42– export from a peatland-dominated catchment as a function of changing SO42– deposition in a long-term (1998–2011), whole-ecosystem, control-impact experiment. Annual SO42– deposition to half of a 2-ha peatland was experimentally increased 6-fold over natural levels and then returned to ambient levels in two phases. Sulfate additions led to a 5-fold increase in monthly flow-weighted MeHg concentrations and yields relative to a reference catchment. Once SO42– additions ceased, MeHg concentrations in the outflow streamwater returned to pre-SO42– addition levels within 2 years. The decline in streamwater MeHg was proportional to the change in the peatland area no longer receiving experimental SO42– inputs. Importantly, net demethylation and increased sorption to peat hastened the return of MeHg to baseline levels beyond purely hydrological flushing. Overall, we present clear empirical evidence of rapid and proportionate declines in MeHg export from a peatland-dominated catchment when SO42– deposition declines

Long-Term Experimental Manipulation of Atmospheric Sulfate Deposition to a Peatland: Response of Methylmercury and Related Solute Export in Streamwater

Changes in sulfate (SO42–) deposition have been linked to changes in mercury (Hg) methylation in peatlands and water quality in freshwater catchments. There is little empirical evidence, however, of how quickly methyl-Hg (MeHg, a bioaccumulative neurotoxin) export from catchments might change with declining SO42– deposition. Here, we present responses in total Hg (THg), MeHg, total organic carbon, pH, and SO42– export from a peatland-dominated catchment as a function of changing SO42– deposition in a long-term (1998–2011), whole-ecosystem, control-impact experiment. Annual SO42– deposition to half of a 2-ha peatland was experimentally increased 6-fold over natural levels and then returned to ambient levels in two phases. Sulfate additions led to a 5-fold increase in monthly flow-weighted MeHg concentrations and yields relative to a reference catchment. Once SO42– additions ceased, MeHg concentrations in the outflow streamwater returned to pre-SO42– addition levels within 2 years. The decline in streamwater MeHg was proportional to the change in the peatland area no longer receiving experimental SO42– inputs. Importantly, net demethylation and increased sorption to peat hastened the return of MeHg to baseline levels beyond purely hydrological flushing. Overall, we present clear empirical evidence of rapid and proportionate declines in MeHg export from a peatland-dominated catchment when SO42– deposition declines