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Item Wetland Assessment and Nutrient Dynamics in North Dakota(North Dakota State University, 2013) Meyers, Lindsey MicheleWetlands provide a variety of services and functions. Studies have highlighted the importance of wetlands in water purification, groundwater replenishment, flood control, sediment and nutrient retention and export, biodiversity, and climate change mitigation and adaptation. Additionally, wetlands are assets to food, fiber, cultural values, recreation, and tourism. These ecosystem services are provided to society free of charge and when eliminated can have negative implications. Therefore, wetland management is important, as wetlands can be lost to agriculture and urbanization. Monitoring wetland condition is a tool to analyze human impact on wetlands. Various types of wetland assessments have been created to measure biological condition. These include vegetative, rapid, functional, and intensive assessments. Data collected from assessments can be utilized for further study and analysis in addition to measuring condition. Physical characteristics can be identified that correlate with wetland condition, which provide clues to how well a wetland is functioning. Wetlands are important to nutrient cycling and storage. The levels of nutrients in vegetation, soil, and water may vary based on parent material, surrounding land use, hydrology, the type of wetland, and types of species present. Wetlands can filter excess nutrients from agricultural and urban runoff to a certain extent. High nutrient loads can cause eutrophication and anoxia and affect the biological community and wetland function. High levels of nutrients and disturbance have been correlated with exotic species invasion and decreased diversity. Stable isotopes of nitrogen and carbon have been applied to measure anthropogenic impact, nutrient sources, and denitrification levels. Four studies were completed during the summers of 2011 and 2012 on wetland assessment and nutrient dynamics across the state of North Dakota. The results indicated the importance of land use regarding wetland condition and nutrient levels. Wetlands in cropland tended to have lower floristic quality and biological condition and higher stable isotope δ15N values. Additionally, levels of phosphorus, nitrogen, and carbon differed by plant type with some indication that cattail invasion alters nutrient cycling. Furthermore, classification and regression tree modeling links wetland buffer, soil, and water data to wetland condition.Item The Impacts of Exotic Species on Native Bee Communities and Interactions in Novel Northern Great Plains Grasslands(North Dakota State University, 2022) Pei, C. K.Human alterations to landscapes impose novel conditions on native plant and animal species. Exotic plants are among these changes and are presently common and prevalent across Northern Great Plains (NGP) grasslands. Their introductions alter plant communities and influence the wildlife species that rely on the resources provided by plant communities. Exotic plants displace native plant species, but we do not understand how or if some exotic plants can provide resources to pollinating insects requiring floral resources. Considering the spread of exotic plants and the important ecological services bees provide, it is important to understand how native bees value and interact with exotic plants, and how exotic plants may shape bee communities in the NGP. To address this, we employ a unique dataset built from a statewide survey of bees and associated plant species across North Dakota grasslands to investigate the broad questions of how bees select between native and exotic floral resources, how exotic grasses may indirectly affect bee diversity through the plant community, and how exotic species dominance changes the interaction structure between bees and plants. From our selection analyses, we found native bumble bees selected for native plants and plant diversity over exotic plants whenever significant selection occurred, while European honey bees selected for exotic plants and floral resource density. However, both benefited from floral resource diversity, indicating that common management may exist for both groups. Invasive grasses did not affect bee richness at a broad scale but negatively influenced particular bees, such as ground-nesting species. We found litter accumulation to be influential over plant communities and particular types of bees based on their life history traits, indicating the need for grassland management practices that prevent homogenous plant structure. Finally, we found that exotic bees and plants influenced bee-plant interaction network properties through their dominance over contemporary pollination networks. This implicates that managing exotic species may be needed to reduce effects on the complex bee-plant interactions and consequent pollination services. Broadly, this work provides further evidence of exotic species effects on ecological communities and the first large-scale assessment of their impacts on bee communities in NGP grasslands.Item Winter Wheat Management for Improving Soil Quality and Reducing Greenhouse Gas Emissions(North Dakota State University, 2014) Aher, Gabriel GarangCarbon dioxide (CO2) and nitrous oxide (N2O) concentrations in the atmosphere have greatly increased in recent times. Intensive agricultural practices, combustion of fossil fuels, deforestation, and wetland drainage have been linked to increased greenhouse gases (GHG) levels. Although scientists are not unanimous in their belief that the increases in GHG is a cause behind recent global temperature rise, there is evidence that increases in GHG might directly increase global temperatures and unpredictable weather occurrences. Since human activity may be partially behind the rise in GHG emissions, it follows that changes in agricultural management might reduce the rate of GHG increases or even mitigate existing increases. Agricultural management practices proposed to mitigate GHG emissions in agricultural soils include conservation tillage, diversified cropping systems, and crop residue management. The objective of this study was to determine the impacts of high-residue no-till systems in a diverse rotation using seven cropping systems in which winter wheat (Triticum aestivum L.) was included or not included. The study was imposed on existing rotations present at the Conservation Cropping Systems Project (CCSP) farm near Forman, ND. The CCSP site was established in 2001 under no-till production and managed by the Wild Rice Soil Conservation District. Analysis of 2006 and 2010 soil organic carbon (SOC) data showed no significant difference between winter wheat rotation treatments and rotation treatments without winter wheat. Analysis of 2012 SOC data resulted in greater SOC in the corn (Zea mays L.)-soybean (Glycine max L.) rotation and lower SOC in the spring wheat (Triticum aestivum L.)-winter wheat (Triticum aestivum L.)-cover crop-soybean rotation. Some rotations had greater SOC than others, but the differences were not related to whether or not winter wheat was included in the rotations. Analysis of residue showed a greater C:N ratio and greater potential N requirement for the subsequent crop in fresh residue compared to aged residue. The COMET-VR model used to estimate SOC levels overestimated SOC in greater diversified rotations and underestimated SOC in lower diversified rotations. No-till production and crop residue retention can increase SOC levels, improve soil quality, and increase SOC sequestration in cropping systems.Item Using Light Detection and Ranging (LiDAR) Technology to Assess Bird-Habitat Relationships: A Case Study from the Northwoods of Maine(North Dakota State University, 2012) Newton, Wesley EugeneAirborne light detection and ranging (LiDAR) is a remote sensing technology that quantifies the travel time of photons emitted in pulses from a LiDAR instrument to travel to and reflect back from objects. Knowing the travel time for the photons and accounting for the speed of light, distances to objects from the instrument can be quantified. When LiDAR is acquired over forested areas some of the pulses will find canopy openings and "penetrate" to the ground with others striking the canopy at various heights above the ground, generating an XYZ point-cloud of eastings, northings, and elevations. Capitalizing on the information in these point-clouds from a June, 2003, acquisition in forested areas of Maine, we characterized the vertical profile of the canopy from which we computed LiDAR-derived explanatory variables for empirical modeling of various response variables (i.e., forest stand metrics, bird species abundance). The first aim of the research reported in this study was to assess the ability of LiDAR-derived explanatory variables to predict forest stand structure than can then be used as input in a suite of habitat-models that predict New England wildlife occurrences (called ECOSEARCH). Using regression analyses and field-collected data, we determined that LiDAR does a good job of predicting various forest stand metrics for the over- and understory (Adj. R2 >0.60 for 14 of 20 models developed). The second aim was to assess the ability of LiDAR-derived explanatory variables to directly predict mean bird abundance within forested areas during their breeding season. We derived a set of minimally correlated LiDAR-derived explanatory variables and used these in regression analyses to predict mean bird abundance from field surveys. Results indicate that LiDAR-derived explanatory variables were useful for predicting the mean abundance of 17 bird species (all with Adj. R2 > 0.2, with 5 models having Adj. R2 > 0.4). The third aim was to utilize the LiDAR-derived habitat-models and apply these across two study sites under varying management scenarios for assessments and planning purposes. Using a simple Euclidean distance metric and under various but realistic assumptions we were able to ascertain optimal management scenarios for five focal bird species.Item Driver Attitudes and Crash Patterns in Western North Dakota Oil Counties: Links between Perceptions and Reality(North Dakota State University, 2014) Kubas, Andrew JohnTraffic safety conditions in the 17-county oil region of western North Dakota have changed considerably in recent years. Roads previously used for low-volume, agricultural purposes are presently utilized at high volumes to serve expanding oil interest. Traffic volume in the region has grown rapidly since the advent of hydraulic fracturing as a viable technique for extracting oil, especially with regard to the overweight and oversized vehicles needed for oil production. Three studies were conducted to understand how changing traffic conditions are perceived by local drivers. First, a survey questionnaire was sent to drivers in the region to measure perceptions of traffic safety priorities. County-level crash data were gathered for rural road crashes in North Dakota between 2004 and 2013 to examine statewide crash trends. Survey responses were linked to crash data and found that safety perceptions from drivers are valid: conditions in oil counties are actually more dangerous than elsewhere in North Dakota. Second, using Decision Theory as a theoretical lens to guide decision-making, crash data were queried to establish if driving conditions in certain parts of the oil region are more dangerous. Proximity to oil wells, city limits, and travel on major roadways were found to have an effect on overall crash severity. Third, written survey responses were qualitatively studied via emergent theme content analysis. Crash types relating to these themes were then subjected to cluster analysis using ArcGIS. Respondent zip codes were matched with crash zip codes to provide a mixed methods approach to understanding key traffic safety issues such as perceived danger, large truck danger, and law enforcement presence.Item Patch-Burn Grazing in Southwestern North Dakota: Assessing Above- and Belowground Rangeland Ecosystem Responses(North Dakota State University, 2021) Spiess, Jonathan WesleyRangelands are heterogeneous working landscapes capable of supporting livestock production and biodiversity conservation, and heterogeneity-based rangeland management balances the potentially opposing production and conservation goals in these working landscapes. Within fire-dependent ecosystems, patch-burn grazing aims to create landscape patterns analogous to pre-European rangelands. Little work has tested the efficacy of patch-burn grazing in northern US Great Plains. We investigated patch contrast in above and belowground ecosystem properties and processes during the summer grazing seasons from 2017 – 2020 on three patch-burn pastures stocked with cow-calf pairs and three patch-burn pastures stocked with sheep. We focused on vegetation structure, plant community composition, forage nutritive value, grazer selection, livestock weight gain, soil nutrient pools, soil microbial community composition, and decomposition activity. We used mixed-effect models and ordinations to determine whether differences: along the time since fire intensity gradient, between ecological sites, and between grazer types existed. Despite no significant shifts in the plant community, structural heterogeneity increased over time as the number of time since fire patches increased and was higher than homogeneously managed grasslands. Grazing livestock preferred recently burned patches where the available forage had a higher nutritive value and lower available biomass than surrounding patches at a given point in time. With the exception of 2018, livestock weight gains were consistent. Soil nutrient pools and microbial abundances differed more by ecological site than by the time since fire intensity gradient, and ecological sites exhibited similar nutrient and microbial responses to the time since fire intensity gradient. That belowground response variables were mostly resistant to patch-burn grazing is supportive of further use of this management, especially given the desirable results with aboveground response variables.Item Smooth Brome (Bromus Inermis) Phenology in the Northern Tallgrass Prairie(North Dakota State University, 2018) Preister, LisaSmooth brome (Bromus inermis) invasion into tallgrass prairie has led to development of methods of control. Prescribed burning is used by the US Fish and Wildlife Service (USFWS) to manage prairie according to a provisional model developed by Willson and Stubbendieck (2000). The model recommends conducting a prescribed burn at the onset of elongation of smooth brome. The USFWS uses the 5-leaf stage as a phenological cue, signaling the initiation of elongation. Variability in smooth brome development limits the reliability of this method. Our objective was to develop an alternative method to determine when smooth brome populations reach the targeted 50% elongation by correlating accumulated growing degree days and population level plant phenological stages (mean stage count) throughout sites in North Dakota, South Dakota, and Minnesota. A linear regression model was used to determine the onset of elongation in the smooth brome population, regardless of leaf stage variation. Field and greenhouse studies confirmed accumulated growing degree days predicted the initiation of elongation. We also compared smooth brome response to different seasonal burn treatments, determining it could be decreased by burning at other times. As part of the USFWS Native Prairie Adaptive Management program, results will be used to assist management decisions regarding the timing of control.Item Visitors' values of natural resources and cultural resources on Dakota Prairie National Grasslands(North Dakota State University, 2010) Steele, Bruce RichardManaging Dakota Prairie National Grasslands requires an understanding of visitor relationships to nature and culture. As national grasslands continue to draw visitors for recreation, relaxation, and wildlife observation the value visitors place on associated resources is important to the management decision process. At the request of the Forest Service, the study focus was specifically on national grasslands visitors. The objectives were to 1) determine the value stakeholders have on our natural resources, 2) determine the value stakeholders place on cultural resources, and 3) national grasslands visitors' perceptions on the origin of federal policies concerning natural and cultural resources. Thus, visitors including interest groups and range scientists were primary sources of data. Qualitative analysis methods were used to determine that for visitors, natural resources were valued more than cultural resources. Furthermore, the general perception of visitors was that policies concerning natural resources originate at local levels whereas cultural resources policies originate at the federal level. Public school systems have had little inclusion of environmental education in their curriculum and the Forest Service has been responsible to keep visitors informed about national grassland ecology. Because the Forest Service mission does not include the preservation of cultural resources there is little initiative by the Forest Service to protect those resources. Therefore, damage to cultural artifacts on national grasslands by uninformed visitors is likely. The future of national grasslands management clearly rests on the integration of natural and cultural resources training and education for both employees and visitors.Item A Plan to Reduce Water Poverty in the Fertile Crescent: Getting from Science to Solutions.(North Dakota State University, 2010) Qtaishat, Tala HussamWater scarcity is an ever-growing worldwide problem. In particular, most Fertile Crescent (FC) countries (i.e., Iraq, Syria, Lebanon, Jordan, Palestine and Israel) face severe problems related to water scarcity. Growing demand for water resources due to increased population and improved living standards, prompted public agencies and others in the Fertile Crescent (FC), a semi-arid region, to seek better ways to manage water. Water scarcity is the most serious natural constraint to the FC's economic grow-th and development. Three potential paths to address water scarcity dilemma are ( 1) nontraditional shifts in water reallocation, (2) innovative supply augmentation methods and (3) identification of substitutes for water in production and consumption. Water reallocation within uses (e.g., agriculture) and among users (e.g., agriculture, industry and municipal) as well as supply augmentation (e.g., desalination, water importing, wastewater treatment, recycling, water conservation, reducing evapotranspiration and storage) can all play a role in extending water resources. A conceptual reallocation method and information from the scientific literature suggest that some reallocation in the name of efficiency may be beneficial. A conceptual supply augmentation method operationalized with secondary data suggests water supply augmentation may also lead to decreasing water scarcity. Ultimately, substitutes for water will be necessary to further minimize water scarcity. These solutions, along with their economic, political, cultural, and technical dimensions and constraints, are presented in a strategic plan format that identifies paths for increasing social benefit of the FC's water resources. The plan will assist decision-makers to identify and understand the constraints and the benefits related to non-conventional options. The plan posits a 20% shift in water from agriculture to municipal and industrial uses over the next 20 years, assumes reasonable supply improvements and speculates about the role of substitutes in the future. The plan further demonstrates a potential allocation of a hypothetical $100 million grant to a fictional FC water authority. These feasible, modest achievements would lessen water scarcity in the FC, by the year 2030.Item Evaluating Financial, Social, and Waterbird Implications of Farming Within Wetlands Imbedded in Agricultural Fields(North Dakota State University, 2022) Toy, DustinWetlands of the Prairie Pothole Region (PPR) provide many ecosystem services to the region such as floodwater attenuation, maintenance of water quality, carbon sequestration, and wildlife habitat. The biophysical process characteristics of the region that have made it beneficial for wildlife have also made the region conducive to cultivation; consequently, many wetlands (>49%) in the PPR have been drained and converted to cropland. Although wetlands are often noted for their natural ecosystem services, their contributions to agriculture are often overlooked. Understanding aspects of PPR wetlands, such as value for migrating waterbirds, how wetlands fit into farming operations, and how farmers perceive the fit of those wetlands in their operations will help to find mutually beneficial solutions to wetland management for farmers and conservation efforts. I evaluated occurrence and densities of various species of waterfowl and shorebirds within agricultural wetlands receiving different manipulations. Most manipulations reduced vegetation heights and proportions of vegetation coverage of the inundated areas of wetlands. Manipulation technique was only important for four species and varied in its effect on density and occurrence probabilities. Most species of waterfowl occurred at higher densities in the low to mid ranges of vegetation coverage. Based on data collected from farmers, I estimated about half of the area of temporary wetlands and nearly one third of the area of seasonal wetlands are planted on average. Soybean yield and profitability from cultivated portions of temporary wetlands were similar to uplands at average precipitation but were significantly lower in seasonal wetlands. Corn profitability was significantly lower for cultivated portions of temporary and seasonal wetlands for average precipitation conditions. The differences were more pronounced under wetter conditions and especially when considering the entirety of wetland area, not just the cultivated portions of wetlands. I examined farmers’ perceptions through a questionnaire regarding how they view agricultural wetlands and how wetlands fit into the respondents’ farming operations. Despite a low response rate, some informative responses may provide a foundation for further exploration of these data. The results of this dissertation may provide an opportunity for farmers and conservationists to find mutually beneficial management practices for agricultural wetlands.