NRSM Masters Theses (Plan A and Plan B)

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All cellulose composites prepared in an ionic liquid.
(2010-12) Zhou, Lili
The overall goal of this project was to investigate all-cellulose composites prepared in a “green” solvent – ionic liquid. The approach was to partially dissolve cellulose and subsequently convert it into a matrix domain embedding the reinforcement domain – the undissolved cellulose. Microcrystalline cellulose (MCC) was partially dissolved in 1-N-Butyl-3-methylimidazolium chloride (BMIMCl) ionic liquid. The dissolved portion of cellulose was precipitated by adding water, and the gels obtained were washed, dried, and pressed into films. The all-cellulose composite films were structurally characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM), while their properties were determined using tensile tests and dynamic vapor sorption (DVS) studies. XRD results verified that the crystallinity index and weight fraction of cellulose I in the composites can be controlled by controlling the soaking time and cellulose concentrations. The tensile test data revealed that the all-cellulose composite produced in this study had mean elastic moduli and strength of up to 4.4 GPa and 49 MPa, respectively, which are in the range of a randomly oriented biofiber-reinforced polymer composites. The tensile properties increased as a response to the composite density, which was found to increase as more cellulose II matrix (from increased dissolution) was present to presumably better fill the voids. This presumption was supported by SEM images of cryo-fractured surfaces. The sorption isotherms obtained from DVS studies showed a non-sigmoidal behavior at low relative humidity levels (<44%), while the equilibrium moisture content values at higher humidity levels closely correlated to the cellulose I crystallinity index of the composites. Overall, this study verified that dissolution of cellulose in ionic liquid can be controlled to control the properties of all-cellulose composites.
American Woodcock Singing-ground Surveys in the western Great Lakes region: assessment of woodcock counts, forest cover types along survey routes, and landscape cover type composition.
(2010-10) Nelson, Matthew Roy
Overview: Counts of American woodcock (Scolopax minor) on the annual Singing-ground Survey (SGS) have undergone long-term declines in both the Eastern and Central Management Regions. However, interpreting these trends is confounded by a lack of information regarding the relationship between counts and habitat. Therefore, I assessed the relationship between woodcock counts and land-cover composition along survey routes using an Information-Theoretic modeling framework. The amount of early successional forest, open space, and a landscape metric Interspersion and Juxtaposition Index (IJI) best explained counts in Wisconsin; in Minnesota, the amount of mature forest, water and models that included open space, wetlands, and early successional forest together best explained counts. These results are, in general, consistent with woodcock-habitat relations described in published literature, and suggest that woodcock counts along SGS survey routes in Minnesota and Wisconsin reflect the amount and composition of land cover along routes, especially the amount and juxtaposition of early successional forest and open space, which were the variables included in competing models for both states. Key Words: shorebird, American Woodcock, Scolopax minor, Central Management Region, Minnesota, Wisconsin, land cover.
Barriers to Barriers: An Exploration of Snow Fence Adoption and Ramón Seed Market Potential
(2020) Motschke, Collin
This Plan B Thesis is comprised of two discrete projects. Each project’s abstract is provided below. An Exploration of Snow Fence Adoption Among Minnesota Landowners Through its Blowing Snow Control Program, the Minnesota Department of Transportation (MnDOT) pays private landowners to install snow fences along state highways to trap snow as it blows across open areas. These barriers, which include trees, shrubs, haybales, permanent fences, and standing corn rows, not only protect Minnesota drivers by increasing visibility and reducing the amount of snow on the roadway, they also save taxpayer dollars, as MnDOT snowplow operators make fewer trips, thus resulting in less fuel consumption and reduced usage of deicers. An ongoing research collaboration between UMN and MnDOT has identified relatively low adoption rates among Minnesota landowners and an associated need for an improved understanding of landowner knowledge, attitudes, and practices related to snow fences. The present study aims to address this area of need by using a mixed-methods approach (listening sessions and surveys) in four regions of the state to uncover landowner constraints, develop an effective outreach plan, and ultimately expand landowner adoption of snow fences. Findings revealed a general lack of program awareness, a wide range of constraints to adoption, and a key recommendation to emphasize MnDOT’s willingness to offer customized, rather than one-size-fits-all, snow fence solutions. An Exploration of U.S. Market Potential for Ramón Seed (Brosimum alicastrum) Since 2011, the University of Minnesota (UMN), in collaboration with the Rainforest Alliance’s Climate, Nature, and Communities in Guatemala Initiative, has been conducting value chain analyses on the ramón seed (Brosimum alicastrum), a nutritious tree seed native to the neotropics. To date, most UMN research has focused on the processes, perspectives, organizational structures, and finances of ramón seed producers in the Maya Biosphere Reserve of Guatemala’s Petén Department. Many of these investigations have mentioned and recommended further study of potential market pathways for ramón seed in the United States’ health food industry. This study employs a variety of methods including interviews with health food market stakeholders, preliminary price evaluations, and novel UMN research collaborations to provide insights into ramón seed market development. Results include a need for improved consumer awareness of ramón seed, a recommendation to avoid low-priced commodity markets, and a suggestion to prioritize ramón’s production narrative when marketing to prospective buyers.
The Benefits of Volunteers: Understanding the impact of volunteers on community capacity to manage urban forest resources A
(2020-07) Johnson, Callissa
Biomass and Sapwood of Green Ash (Fraxinus pennsylvanica) in the Twin Cities Metro Area
(2017) Olson, Derik
Canopy transpiration and water yield changes following forest canopy conversion in Northern Minnesota.
(2011-03) Shannon, Joseph
In 1980, the upland aspen (Populus tremuloides & P. grandidentata) portion of the S6 watershed of the Marcell Experimental Forest was clearcut and subsequently converted to red pine (Pinus resinosa) and white spruce (Picea glauca). Comparisons of water yield observed at S6 and that predicted using the aspen dominated S2 control watershed, suggest that streamflow from S6 has decreased over the past two decades as the conifers have matured. Granier-style thermal dissipation probes were used to quantify sap flux in 36 trees in S2 and S6 throughout the growing season to determine if transpiration rates differed between the two watersheds. Representative sample trees were selected according to factors which may cause sap-flux rates to differ: tree species, slope position, and slope aspect. Using forest inventory data, sap-flux rates were up-scaled to watershed canopy transpiration. Transpiration losses in the S6 watershed were 30% greater than those in S2 for the duration of the study period. Differences were primarily driven by a longer growing season in conifers and greater forest basal area in S6. By representatively sampling forest species it is possible to show that 40 - 50% of transpiration in each watershed is the result of one dominant species, red pine or aspen, in the experimental or control watersheds respectively. Future use of these data will include combination with concurrent interception and flow routing studies to better evaluate hydrologic impacts of similar management decisions in the future. Forest conversion is an ongoing management strategy that brings about long-term effects on streamflow. Understanding these effects allows better prediction of the effect of management on water resources.
Disturbance dynamics and carbon storage in southern boreal mesic aspen mixedwood forests of northern Minnesota, USA.
(2011-05) Reinikainen, Michael Richard
One emerging objective related to forest management is developing silvicultural systems that increase the levels of carbon storage so as to mitigate or offset atmospheric concentrations of carbon dioxide. Understanding the ecological factors and conditions that led to the development of forest stands with high levels of carbon storage can allow for the formulation of management prescriptions that emulate the frequency, timing, and severity of disturbances leading to these conditions. The aims of this thesis were to (1) generate an understanding of the factors affecting stand-level structural and compositional development in southern boreal mesic aspen mixedwoods (hereafter referred to as ‘aspen mixedwoods’), and (2) identify relationships between carbon storage, stand characteristics (e.g., composition and structure) and disturbance histories. Dendroecological methods were used to detail the mechanisms by which nine aspen mixedwood stands in northern Minnesota developed in terms of composition and structure over the last nine decades. With that knowledge and detailed plot-level measurements of forest carbon pools, relationships between patterns of carbon storage resulting from various disturbance histories and compositional mixtures were examined. Dendroecological reconstructions demonstrated that the development of mature aspen mixedwoods was strongly influenced by the defoliation of trembling aspen (Populus tremuloides) by forest tent caterpillar (FTC: Malacosoma disstria) and of balsam fir (Abies balsamea) by eastern spruce budworm (SBW: Choristoneura fumiferana), resulting in complex multi-aged forests. Notably, disturbance-induced structural and compositional changes began as early as 30 years after stand initiation. Concerning carbon storage, stands with a high proportion of aspen stocking resulted in greater total ecosystem (TEC) and tree carbon (TREEC) storage with an opposite trend observed with proportion of conifer, particularly balsam fir. However, in light of recent disturbance, stands containing a greater diversity of tree species and a greater proportion of conifer stems had higher rates of tree carbon increment over the last two decades than plots with a greater proportion of aspen. Furthermore, lower levels of TEC in plots that had experienced elevated rates of disturbance over the last three decades were documented. Collectively, these findings highlight the influence of low to moderate severity disturbances on the patterns of carbon storage and compositional and structural complexity within these systems. As such, regional patterns of natural disturbance present a challenge within the context of managing for highly productive mature aspen mixedwoods; however, the restoration of historically important species (i.e., Picea glauca, Pinus strobus and Thuja occidentalis), specifically long-lived species resistant to FTC and more importantly SBW, may offer a means to store large amounts of carbon for longer periods.
Effects of site and climate characteristics on forest invasibility by non-native plants in the Midwest.
(2010-07) Kurtz, Cassandra Marie
Non-native invasive plant (NNIP) species can have significant effects on forest regeneration, structure, biodiversity, and wildlife habitat, costing billions of dollars annually. Understanding how NNIPs in the Midwest may spread in the future requires understanding their response to site and climate characteristics. Current research suggests climate change may influence invasive plant presence and spread. In this study, I modeled the relationship between invasive species presence, site characteristics (e.g. disturbance, live tree volume, city distance, edge distance, physiography, and type of water [e.g. streams] present on plot), and climate (annual average number of days the temperature is ≥ 90˚F and annual average number of days the temperature is ≤ 32˚F) for five non-native invasive plants (multiflora rose [Rosa multiflora], common buckthorn [Rhamnus cathartica], non-native bush honeysuckles [Lonicera spp.], garlic mustard [Alliaria petiolata], and reed canary grass [Phalaris arundinacea]) sampled by the USDA Forest Service’s Forest Inventory and Analysis program in seven Midwestern states for 2005-2006 Species’ response to site and temperature predictors varied due to trait differences such as shade tolerance and moisture affinity. For most species, presence was positively related to biotic disturbance (disease(s) and/or animal(s)) and mesic physiography and negatively related to distance from a city or a nonforest edge. The best predictor for the presence of NNIPs was annual average number of days the temperature is ≤ 32˚F, with all five species presence correlated with the annual average number of days the temperature is ≤ 32˚F. Understanding the effect of site characteristics and climate on NNIP distribution provides insights into important drivers of species presence at a regional scale and allows land managers, scientists, and concerned citizens to predict invasion risk and future ecosystem response.
Evaluating Watershed Outreach Interventions in the Lower Kaskaskia River Watershed
(2012-10-11) Yaeger, Christine
Effective programs (that meet programmatic goals) and efficient programs (which require reasonable effort) have a significant role in encouraging pro-environmental behavior and decreasing non-point source pollution. A missing component of many outreach programs and interventions is evaluating effectiveness and efficiency. This evaluation assessed outreach interventions associated with the Watershed Health Integrated Research project in the Lower Kaskaskia River Watershed in southwestern Illinois, USA. Outreach interventions included a community research team, a website, citizen and leader-focused workshops, and summary reports. Through developing the Model for Integrated Watershed Management Assessment, this evaluation examined the degree to which interventions fulfilled project objectives and the amount of effort required. Objectives-oriented evaluative criteria included taking a participatory approach, tailoring and appraising programs, and informing and empowering communities. Effort-oriented criteria included personnel numbers, hours, and costs. Data sources included correspondence with the project team, pre/post tests, and evaluative surveys. Results suggest that the citizen workshop was the most effective intervention in that it fulfilled all the project objectives, yet it was the least efficient because it required a high level of effort. None of the interventions were clearly more efficient. The community research team, summary reports, and the leader workshop fulfilled some objectives and required moderate effort, while the website fulfilled few goals and required a moderate effort. These findings can help practitioners with limited time and financial resources strategically choose outreach efforts based on efficiency and effort required. Additionally this evaluation further develops the limited field of watershed outreach evaluation.
Factors influencing detection of American woodcock during singing-ground surveys.
(2011-07) Bergh, Stefanie M.
Abstract summary not available
Hydrologic, nutrient, and sediment responses of restored perennial vegetation/wetland complexes in southern Minnesota.
(2012-05) Fransen, Greg David
The Blue Earth River basin, located in the prairie pothole region of northern Iowa and southern Minnesota, is intensively ditched and drained to improve agricultural production. Agricultural drainage systems increase watershed drainage density and can efficiently transport easily leachable agricultural contaminants, such as nitrate, to receiving water bodies. This thesis examines the hydrologic and water quality benefits provided by two restored perennial vegetation-wetland complexes in the Elm Creek subwatershed of the Blue Earth River basin. Flow measurements and water quality samples were collected at the wetland outlets and at drain tiles and surface channels flowing into the wetlands. Four years of flow data showed that the wetlands reduced the magnitude of peak flows to Elm Creek, but that they did not significantly reduce water yield compared to the agricultural watersheds. The restored wetlands decreased nitrate export by 85 percent during the months of April to June, the period when nitrate from agricultural drainage water contributes to formation of the “dead zone” in the Gulf of Mexico. The wetlands did not significantly decrease phosphorus or sediment export to Elm Creek. Water quality benefits attained by trapping phosphorus and sediment from surface runoff were offset by internal phosphorus loading, algal blooms, and sediment resuspension. Empirical modeling of one wetland basin showed that wind speed and wind direction could explain 60 percent of the suspended sediment concentration within the wetland. Active management of water levels and wetland vegetation are presented as strategies to reduce sediment and phosphorus export from restored wetland basins.
Impacts of biomass harvesting on biomass, carbon, and nutrient stocks in populus tremuloides forests of Northern Minnesota, U.S.A.
(2012-02) Klockow, Paul Alan
Globally, there is widespread interest in using forest-derived biomass as a source of bioenergy. While conventional timber harvesting generally removes only merchantable tree boles, harvesting biomass feedstock can remove all forms of biomass (i.e., trees down through to forest floor material) resulting in a greater loss of biomass, nutrients, and habitat from a site. To investigate the potential impacts of this practice, this study examined the initial impacts (pre- and post-harvest) of various levels of slash and live-tree retention on biomass and nutrient stocks in Populus tremuloides-dominated forests of northern Minnesota. Treatments examined included 0%, 20%, and 100% slash retention with no, dispersed, and aggregate live-tree retention. Slash retention was the primary factor affecting immediate post-harvest biomass and nutrient stocks within total ecosystem and woody debris pools. High levels of biomass and nutrients in harvest slash were observed in all treatments compared to the unharvested control. Typically, 100% slash retained treatments contained significantly greater biomass and nutrient stocks than no slash retained treatments. Stocks of biomass and nutrients within the 20% slash retained treatment, a slash retention level currently recommended by Minnesota’s biomass harvesting guidelines, were generally similar to both no slash retained and 100% slash retained treatments. Given the importance of fine woody debris as a source of nutrients following harvest, nutrient concentrations were measured across an array of woody debris size and decay classes within the Populus tremuloides-dominated forests examined. Results indicate that fine woody debris has significantly greater nutrient concentrations than coarse woody debris. In addition, nutrient concentrations generally increased within both coarse and fine woody debris as decay progressed. Collectively, the results of this study underscore the importance of deliberate retention of fine woody debris as a source of nutrients following harvests of biomass feedstocks.
The influence of natural disturbance-based silviculture treatments on northern hardwood forests in Northeastern Minnesota, USA.
(2010-12) Bolton, Nicholas William
Natural disturbance-based silviculture (NDBS) has been suggested as an approach for promoting late-successional forest characteristics and maintaining native biodiversity in managed forests. Harvest gaps based on the natural disturbance patterns found in the upper Great Lakes (46 study gaps) were created throughout northern hardwood forests in northeastern Minnesota, USA, during the winters of 2002 and 2003. Gaps were measured 6- and 7-years post-treatment and subsequent analysis of these measurements was used to evaluate the success of these treatments at meeting structural and compositional objectives. Results indicated that these gaps have done little to increase tree diversity, including the recruitment of shade mid-tolerant species; however, the richness of herbaceous understory vegetation has responded positively to larger gap sizes. Herbaceous species increasing in harvest gaps included Actaea spp. L. (baneberry), Botrychium virginianum L. (rattlesnake fern), Mertensia paniculata Aiton (Northern bluebell), Rubus idaeus L. (red raspberry), Sanguinaria canadensis L. (bloodroot) and Cirsium arvense L. (Canada thistle). Results also indicated that subtle patterns were found among species spatial establishment within gaps (e.g., gap edge and gap center) and species that expressed no preference between the intact forest and harvest gaps. Levels of downed coarse woody debris (CWD) differed among gap size and all gaps had lower levels of CWD compared to the surrounding intact forest. Due to the historical importance of Betula alleghaniensis in these systems, the factors affecting the recruitment of this species were also investigated. Based on these investigations, it was found that B. alleghaniensis establishment was strongly related to highly decayed, large coniferous pieces of CWD with little recruitment occurring on the undisturbed forest floor. As such, providing appropriate seedbed conditions for shade mid-tolerant species and utilizing natural canopy gap sizes would improve the success of maintaining this species on the landscape.
The influence of stand stocking level on the growth and structure of managed old-growth northern hardwoods.
(2010-09) Gronewold, Christopher Alan
Summary abstract not available.
Microscopic and thermal characterization studies of heterogeneous biocatalysis: polyurethane film immobilized enzymes and degradation of algal cells.
(2011-07) Song, Wei
Heterogeneous biocatalysis, associated with either solid-state biocatalyst systems or solid-state substrate systems, has garnered a lot of interest for chemical synthesis, bioseparation, and biosensing. In the pursuit of high efficiency, the characterization of the physical structure of solid-state biocatalysts and solid-state substrates is necessary to provide detailed information and deepen the understanding for the heterogeneous biocatalytic systems. In this study, microscopic and thermal analytical methods were utilized to characterize the physical structure of solid-state biocatalysts and solid-state substrates. Particularly, we chose the versatile polymer polyurethane (PU) to immobilize enzymes as model solid-state biocatalysts. Two important physical properties, enzyme distribution and glass transition temperature (Tg), were analyzed. It was found that several preparation parameters, including hydrophobic/hydrophilic properties of resin and cross-linker for PU film, weight ratio of starting materials, and mixing speed, showed significant influences on enzyme distribution and Tg. Using microscopic and thermal characterization methods, we further studied the integrity of enzyme-containing PU film against water. The enzyme was found prone to leak from the PU film, indicating incompleteness of cross-linking with PU. Several approaches (e.g., increasing the reaction time and using a hydrophilic cross-linker) were explored in this work to promote better cross-linking between the enzyme and PU matrix. The hydrophilic cross-linker (Bayhydur 302) demonstrated 70% improvement in retaining the enzyme against 24 hours of washing compared to a hydrophobic cross-linker (DESMOPHEN N3600). Moreover, algae cells were studied as model solid-state substrates. We report a novel enzymatic method to disrupt the cell wall and release lipids from the algae cells. Microscopic analysis indicated that the cell wall of Chlamydomonas reinhardtii (C.R.) algae was disrupted after being treated by a three-step method, which included one hour of incubation in 4 M of lithium chloride, eight hours of hydrolytic reaction in enzyme solution, and one cycle of freeze/thaw process. Protease Subtilisin Carlsberg was found effective in catalyzing the degradation of C.R. cell wall due to its unspecific activity toward peptide bonds.
Minnesota Department of Natural Resources Firearms Safety Hunter Education Program Evaluation Report
(2014-03) Courtney, Arielle
Minnesota landowners’ habitus and interest in perennial energy crops.
(2012-06) Schulman, Candi Marie
Abstract summary not available
Nest-site selection and nesting ecology of red-headed woodpeckers.
(2012-05) Waldstein, Ariane Lentz
Red-headed woodpeckers (Melanerpes erythrocephalus) were once a common and widespread species in the Midwest but have declined sharply in the last 40 years. This species is a Minnesota Species of Greatest Conservation Need and an oak-savanna specialist; its decline is ascribed to severe habitat loss throughout the Upper Midwest. Despite numerous oak savanna restoration efforts throughout Minnesota, populations continue to decline, and most restoration sites have failed to attract red-headed woodpeckers. Most restoration focuses on prescribed fire but few studies have examined red-headed woodpecker habitat use and nest success in a long-term managed landscape. This thesis explores red-headed woodpecker nest-site selection and distribution at Cedar Creek Ecosystem Science Reserve (Chapter 1) and also describes a cavity camera system to measure woodpecker nest success (Chapter 2). Using data collected at 102 nest sites and 104 random, non-used sites, logistic regression models showed that woodpeckers preferred low densities of small snags and high densities of trees with dead limbs < 10 m above ground level. Models also showed a preference for large dead nest trees. These results are consistent with other studies and are likely a function of this species’ diverse foraging ecology. Examination of the distribution of nests revealed that the highest density occurred in areas burned between 20 - 25 times since 1964. Implementation of a high-frequency burn regime may be effective at creating red-headed woodpecker habitat. The cavity camera system utilized in 2011 was cheaper and easier to assemble than published designs (Chapter 2). One season of use revealed an average of 3 nestlings and two instances of nest depredation.
Observation to Action: How geospatial data is used for the tracking and management of Invasive Phragmites in Minnesota
Sackett, Danielle; sack0093@umn.edu; Sackett, Danielle; University of MN, CFANS, NRSM, Joe Knight
This paper discusses the importance of monitoring and managing invasive species, particularly Phragmites australis, in the Great Lakes region of Minnesota. Invasive species can negatively impact the local environment, including water quality and native flora/fauna communities, which can, in turn, affect property values and the State's economy, which heavily relies on recreational use of water resources. Management efforts to control invasive species rely on cooperation between governmental agencies, non-governmental organizations, and the public. Tracking the spread of invasive species is vital to their control, and data provided by citizen scientists, landowners, and lake associations is critical to the accuracy of predictive computer models. GIS and other mapping programs can increase success rates while reducing costs of management by using geospatial data. Successful management programs involve early detection and rapid response protocols and monitoring of treated areas to ensure control of the invasive species is achieved. It is important to have infrastructure in place for reporting new populations that both researchers and the public can use to ensure the most accurate data is being used to create ED/RR programs.
Post-stratified estimation of Coarse Woody debris Volume using the down woody materials sample of forest inventory and analysis.
(2010-05) Hatfield, Mark A.
The Forest Inventory and Analysis (FIA) program of the USDA Forest Service conducts a nation wide survey of America’s forests. FIA field crews collect data on tree size, condition, and species, as well as data on the conditions in which they grow from a network of permanent ground plots known as Phase two plots (P2). FIA crews also collect more detailed forest health indicators, including data on Coarse Woody Materials (CWD), on a 1 16 subset of the P2 sample. This subset is known as the Phase 3 (P3) sample. FIA regularly publishes reports on the quantity and quality of America’s forests using data from the P2 sample. A post-stratified estimation technique is used increase the precision of the estimates without increasing the sample size. Currently, research on how to best apply the post-stratified estimator to produce estimates of the P3 forest health indicators has been lacking. This thesis will address this gap by testing 18 candidate geospatial layers (both categorical and continuous) as stratification layers to produce estimates of CWD volume in the Lake-states region of Minnesota, Wisconsin, and Michigan. Continuous geospatial layers will be broken into two to five strata using an optimization algorithm. A simulation experiment is used estimate the long term effectiveness of successful geospatial layers. The simulation experiment is performed to compare the conditional and unconditional variance estimators of the post-stratified estimators. Successful geospatial layers are then applied to sub-populations of varying sizes to determine the effect of spatial extent on the post-stratification method. Stratification layers derived from remote sensing products provided the best results. Using two or three strata is recommended because further partition of the population simply produces ineffective sliver strata. No difference was detected between the two competing variance estimators. The effect of spatial extent of the stratification was volatile. The use of large spatial extents is recommended. The conclusion of this thesis summarizes the lessons learned throughout as well as ideas for future research on the topic.