Minnesota’s Twin Cities have long been powerful engines of change. From their origins in the early nineteenth century, the Twin Cities helped drive the dispossession of the region’s Native American ...peoples, turned their riverfronts into bustling industrial and commercial centers, spread streets and homes outward to the horizon, and reached well beyond their urban confines, setting in motion the environmental transformation of distant hinterlands. As these processes unfolded, residents inscribed their culture into the landscape, complete with all its tensions, disagreements, contradictions, prejudices, and social inequalities. These stories lie at the heart of Nature’s Crossroads . The book features an interdisciplinary team of distinguished scholars who aim to open new conversations about the environmental history of the Twin Cities and Greater Minnesota.
With a booming economy that afforded numerous opportunities for immigrants throughout the 1990s, the Twin Cities area has attracted people of African descent from throughout the United States and the ...world and is fast becoming a transnational metropolis. Minnesota's largest urban area, the region now also has the country's most diverse black population. A closely drawn ethnography,Creating Africa in America: Translocal Identity in an Emerging World Cityseeks to understand and evaluate the process of identity formation in the context of globalization in a way that is also site specific. Bringing to this study a rich and interesting professional history and expertise, Jacqueline Copeland-Carson focuses on a Minneapolis-based nonprofit, the Cultural Wellness Center, which combines different ethnic approaches to bodily health and community well-being as the basis for a shared, translocal "African" culture. The book explores how the body can become a surrogate locus for identity, thus displacing territory as the key referent for organizing and experiencing African diasporan diversity. Showing how alternatives are created to mainstream majority and Afrocentric approaches to identity, she addresses the way that bridges can be built in the African diaspora among different African immigrant, African American, and other groups. As this thoughtful and compassionate ethnographic study shows, the fact that there is no simple and concrete way to define how one can be African in contemporary America reflects the tangled nature of cultural processes and social relations at large. Copeland-Carson demonstrates the cultural creativity and social dexterity of people living in an urban setting, and suggests that anthropologists give more attention to the role of the nonprofit sector as a forum for creating community and identity throughout African diasporan history in the United States.
A method for characterizing aggregate stability with repeated laser diffraction measurements was tested on soils spanning the prairie-forest ecotone in northern Minnesota, USA. These soils formed in ...similar parent material but display a wide range of upper horizon morphology, organic carbon content, and chemistry, allowing assessment of the method's performance over a wide range of aggregate stability and its utility in identifying factors influencing aggregate behavior. Equations representing fine material release through breakdown of two aggregate populations as first-order processes were fit to experimental data. The best-fit parameters for these equations, and an additional index of persistent water-stable aggregate content, indicated distinct differences in aggregate behavior among the major horizons of Mollisols and Alfisols. Linear models were developed to explore the relationships between these parameters and soil physicochemical characteristics for the dataset as a whole and for subsets corresponding to four zones with different vegetation history, soil orders, and major soil horizons. The relationships identified were relatively weak (R2 = 0.30 to 0.70). The best predictors for the parameters representing early disintegration of less stable aggregates were cation exchange capacity (CEC) and effective CEC (ECEC) for the whole dataset, although organic carbon and nitrogen contents also emerged as predictors for forest and Alfisol subsets. The best predictors for the index of persistent water-stable aggregate content were organic carbon content, base saturation, or exchangeable Ca/Mg ratio, depending on the particular subset and fine material size fraction used in the analysis. The relatively weak explanatory power of organic carbon content as a predictor of aggregate behavior in these experiments was somewhat surprising, given prior work on aggregate stability. Both CEC and ECEC may serve as proxies for the various combinations of organic matter and clay content that influence aggregate stability in these samples, explaining their importance as predictors. It is likely that other factors not examined in this research contributed to aggregate stability, including carbonate content, clay mineralogy, and differing frequency and types of pedoturbation under grassland and forest. The results of this study are relevant to reconstructing the development of texture-contrast profiles as forest invaded grassland over the past 4000 in the study area, as documented by paleoecological research. In particular, loss of organic matter below a thin A horizon may have facilitated initial development of an E horizon in which weak aggregation favored clay eluviation; loss of clay would then have weakened aggregate stability still further. We suggest this new method for assessing aggregate stability can also be applied to research on soil erosion and runoff potential as affected by land use and management.
•Soil aggregate behavior assessed using repeated laser diffraction measurements.•Dynamics of aggregate disintegration can be modeled as first-order processes.•Method applied to comparison of aggregate behavior in grassland and forest soils.•Aggregate's stability and disintegration dynamics vary by soil order and horizon.•Disintegration rates and water-stable aggregate content related to soil properties.
Most studies of emancipation's consequences have focused on the South. Moving the discussion to the North, Leslie Schwalm enriches our understanding of the national impact of the transition from ...slavery to freedom.Emancipation's Diasporafollows the lives and experiences of thousands of men and women who liberated themselves from slavery, made their way to overwhelmingly white communities in Iowa, Minnesota, and Wisconsin, and worked to live in dignity as free women and men and as citizens.Schwalm explores the hotly contested politics of black enfranchisement as well as collisions over segregation, civil rights, and the more informal politics of race--including how slavery and emancipation would be remembered and commemorated. She examines how gender shaped the politics of race, and how gender relations were contested and negotiated within the black community. Based on extensive archival research,Emancipation's Diasporashows how in churches and schools, in voting booths and Masonic temples, in bustling cities and rural crossroads, black and white Midwesterners--women and men--shaped the local and national consequences of emancipation.
Sediment delivery from the Le Sueur River watershed is a major concern in the turbidity-impaired Minnesota River. As part of a broader effort to develop a sediment budget for the Le Sueur River, this ...study implemented a process-based watershed hydrology and upland erosion model, Water Erosion Prediction Project (WEPP), to simulate hydrology and sediment dynamics in several land-use/land-cover scenarios. The Geo-spatial interface for WEPP (GeoWEPP) was used to characterize upland overland flow elements based on their land use/land cover, soil, and slope profiles. These characteristics were used as inputs for the WEPP model to estimate runoff fluxes, soil loss rates, and sediment delivery ratio (SDR) for three environmental scenarios: current land-use/land-cover with agricultural lands under fall mulch till management (scenario 1), current land-use/land-cover with agricultural lands under no till management (scenario 2), and pre-settlement land-use/land-cover (scenario 3). Over a simulated 30-year period (1979–2008), the runoff depth, soil loss rate and SDR were estimated to be 86mm, 2.6T/ha, and 0.84 for scenario 1; 73.8mm, 0.5T/ha, and 0.9 for scenario 2; and 70.9mm, 0.2T/ha, and 0.73 for scenario 3.
•We estimated sediment yield, soil loss and runoff at field scale using WEPP.•We compared sediment and runoff values for 3 land uses scenarios.•We found that sediment and runoff vary by land use and field management.•WEPP gave a comparable result with observed sediment.
Large subsurface treatment systems (LSTS) and rapid infiltration basins (RIB) are preferred onsite wastewater treatments compared to direct discharge of treated wastewater to streams and adjacent ...facilities. Discharge of these wastewater treatments may result in contaminant loading to aquifers that also serve as drinking water sources downgradient from the discharge site. Until recently, few studies have characterized the contribution of micropollutants (e.g. pharmaceuticals, fragrances, flame retardants, etc.) to receiving aquifers. We conducted a pilot project to characterize the occurrence of micropollutants in groundwater downgradient from 7 on-site treatment systems in Minnesota, USA: 5 community LSTS and 2 municipal RIB. One downgradient monitoring well was sampled three times at each facility over one year. Of 223 micropollutants analyzed, 35 were detected. Total sample concentrations ranged from 90 to 4,039 ng/L. Sulfamethoxazole (antibiotic) was detected in all samples at concentrations from 7 to 965 ng/L. Other pharmaceuticals (0.12-1,000 ng/L), organophosphorus flame retardants (10-500 ng/L), and other anthropogenic chemicals (4-775 ng/L) were also detected. The numbers and concentrations of micropollutants detected were inversely related to dissolved oxygen and depth to water. Ratios of pharmaceutical concentrations to human-health screening values were <0.10 for most samples. However, concentrations of carbamazepine and sulfamethoxazole exceeded screening values at two sites. Study results illustrate that large on-site wastewater systems designed to discharge to permeable soil or shallow groundwater effectively deliver pharmaceuticals and other micropollutants to groundwater aquifers and could contribute micropollutants to drinking water via water supply wells.
When Stephen Lehmkuhle became the chancellor of the brand new University of Minnesota-Rochester campus, he had to start from scratch. He did not inherit a legacy mission that established what the ...campus did and how to do it; rather, he needed to find a way to rationalize the existence of the nascent campus. Lehmkuhle recognized that without a shared understanding of purpose the scope of a new campus expands at an unsustainable rate as it tries to be all things to all people, and so his first act was to decide on the driving purpose of the campus. He then used this purpose to make decisions about institutional design, scope, programs, and campus activities. Through personal and engaging anecdotes about his experience as the inaugural chancellor at the University of Minnesota-Rochester, Lehmkuhle describes how higher education leaders can focus on campus purpose to create new and fresh ways to think about many elements of campus operation and function, and how leaders can protect the campus’s purpose from the pervasive higher education culture that is hardened by history and habit.
The history of mercury (Hg) inputs to 55 Minnesota (U.S.A.) lakes was reconstructed from 210Pb (lead-210)-dated sediment cores to determine if erosion of soils from agriculture and urbanization ...contributes a significant loading of Hg to lakes, and whether lakes near Hg-emitting facilities receive appreciable local atmospheric deposition. Modern (1994-1997) Hg accumulation and Hg flux ratios (modern:preindustrial) increase significantly with the percentage of watershed area under urban or agricultural land-use. Both past and modern Hg accumulation rates are strongly correlated with the flux of total aluminum (Al), a tracer for soil erosion. Modern Hg accumulation rates are substantially higher in the Minneapolis-St. Paul metropolitan area and in agriculturally dominated south-central Minnesota than in the forested northeastern part of the state, largely because of erosional inputs of soil-bound Hg from disturbed catchments. Modern Hg loading from direct atmospheric deposition is also greater in the metropolitan region than in the rural areas of south-central or northeastern Minnesota. However, some of the excess loading to urban lakes may also be a legacy of formerly high Hg deposition to urban watersheds. A decline in local Hg emissions from peak levels in the 1970s coupled with reduced erosional inputs has cut Hg loading to many metro-area lakes by more than half.
Eastern red cedar (ERC, Juniperus virginiana L.) is a common tree species in agroforestry plantings and has great potential for bioenergy production due to physical and chemical characteristics of ...its biomass. The objective of this study was to assess the effects of ERC plantings on carbon (C) sequestration and selected soil quality parameters in existing plantings across the northern U.S. Great Plains. Nine locations were selected in five states with mean annual precipitation (MAP) from 446 to 999 mm and mean annual temperature (MAT) from 4.4 to 10.0°C. Infiltration was measured using the twin ring technique at nine sites in each tree planting and adjacent field (crop, pasture, or hay) at each location. Following infiltration measurements, a 4.8 cm‐diameter soil core to 30 cm depth was collected from inside one infiltration ring of each pair for bulk density, pH, aggregate stability, soil organic carbon (SOC), and total nitrogen (TN) analyses. Penetration resistance in 2.5 cm increments to 30 cm depth was measured in the other infiltration ring. SOC stocks under ERC were significantly higher than in the adjacent field soil at five of the locations and, for all locations, averaged 16.8% greater than in the adjacent field. The estimated SOC accumulation rate for the eight locations with uniform tree stand age averaged 0.30 Mg C ha−1 year−1. Most locations had higher TN and C/N and lower bulk density beneath ERC. Fewer differences for infiltration and penetration resistance and smaller and less consistent differences for pH and aggregate stability were observed. Tree aboveground C stocks were estimated to increase an average of 2.05 Mg C ha−1 year−1. Estimated tree aboveground biomass C and SOC stocks under ERC and in adjacent fields were strongly correlated with MAP. Potential ERC planting for C sequestration or bioenergy feedstock production is not likely to significantly degrade soil quality and may improve soil physical or chemical quality for locations in the US Great Plains.
Core ideas
Eastern red cedar (ERC) is a common tree species with biomass that is well suited for biofuel production.
ERC effects on soil quality should be evaluated if considered for bioenergy feedstock production.
Soils beneath ERC had higher SOC, TN, C/N, and lower bulk density than adjacent fields at most locations.
ERC C accumulation and SOC were highly correlated with MAP.
ERC plantings had generally positive impacts on soil quality.
High concentrations of polycyclic aromatic hydrocarbons (PAHs) are accumulating in many urban stormwater ponds in Minnesota, resulting in either expensive disposal of the excavated sediment or ...deferred maintenance by economically challenged municipalities. Fifteen stormwater ponds in the Minneapolis—St. Paul, MN, metropolitan area were studied to determine sources of PAHs to bed sediments through the application of several environmental forensic techniques, including a contaminant mass balance receptor model. The model results were quite robust and indicated that coal tar-based sealant (CT-sealant) particulate washoff and dust sources were the most important sources of PAHs (67.1 %), followed by vehicle-related sources (29.5 %), and pine wood combustion particles (3.4 %). The distribution of 34 parent and alkylated PAHs was also evaluated regarding ancillary measurements of black carbon, total organic carbon, and particle size classes. None of these parameters were significantly different based on major land-use classifications (i.e., residential, commercial, and industrial) for pond watersheds. PAH contamination in three stormwater ponds was high enough to present a risk to benthic invertebrates, whereas nine ponds exceeded human health risk-based benchmarks that would prompt more expensive disposal of dredged sediment. The State of Minnesota has been addressing the broader issue of PAH-contaminated stormwater ponds by encouraging local municipalities to ban CT-sealants (29 in all) and to promote pollution prevention alternatives to businesses and homeowners, such as switching to asphalt-based sealants. A statewide CT-sealant ban was recently enacted. Other local and regional jurisdictions may benefit from using Minnesota’s approach where CT-sealants are still used.
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