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Tremendous variation exists in how cities, states, countries, and other jurisdictional areas classify water use and consumption. Additionally, water conservation measures have become more common in the past few decades, but little is known about how these conservation measures are implemented across the landscape. The goal of this study is to increase the breadth of knowledge regarding municipal water-use data: retention, storage, availability, and delving into water conservation measures, along with the impact of shale oil extraction on municipal water use in the Bakken region. Two questionnaires were developed and administered to all municipalities in the state of North Dakota, USA with populations greater than 1000 residents, and between 500 and 1000 residents in the Bakken region (total number (n) =59) willing to participate. Results indicate water conservation measures are inconsistent across the landscape, and data categorization at the municipal level is minimal which limits the analysis, interpretations, and projections that can be made from the data. Additionally, the Bakken region is different from the rest of the state in how they acquire water and sell water to other large scale users. Results from this study will aid water use professionals worldwide by providing valuable information on water-use data, access, storage, and impacts of large water users, such as shale oil extraction, on municipal water. This information will also help researchers to understand availability of data for making comparisons across different areas, assessing trends, and making water use projections.

The composition of the greenline plant community is linked to the stability of riparian ecosystems. Cool season exotic grasses are invading native plant communities across the northern Great Plains, potentially compromising streambank stability and increasing the risk of erosion within riparian ecosystems. To determine how the species composition of the greenline community impacts stream type and the risk of streambank erosion, thirty five reaches across five watersheds were sampled to determine the dominant greenline vegetation. At each reach, a cross-section was sampled to determine stream type, greenline vegetation, and risk of streambank erosion. Channel types were delineated using Rosgen’s classification of natural rivers. Canopy cover and composition was assessed using the line point intercept method along a 30.5 m transect in the greenline community. Plants recorded were grouped by their wetland indicator status for the central Great Plains. The Bank Erosion Hazard Index (BEHI) was used to assess the streams risk of erosion by calculating the difference between the bank height and bank full height, average plant rooting depth and density, bank angle degree, and the dominant texture of the bank material. Bank height ratio (BHR) was assessed as a measure of streambank stability and floodplain connectivity. A Nonmetric Multidimensional Scaling ordination was performed to analyze plant community influences. Analysis of the data determined that the most stable stream types (E and C channels), lower BEHI scores, and stable bank height ratios were associated with high amounts of litter and facultative wet species. In comparison, unstable F channels were associated with early successional species and bare ground. Sites with the higher BEHI scores were associated with greenlines comprised of upland and facultative upland and saline tolerant species. Late successional facultative wetland species were found to provide the most protection to intermittent streambanks.

Toxic cyanobacterial blooms, often containing multiple toxins, are a serious public health issue. However, there are no known models that predict a cyanotoxin mixture (anatoxin-a, microcystin, saxitoxin). This paper presents two cyanotoxin mixture models (MIX) and compares them to two microcystin (MC) models from data collected in 2016–2017 from three recurring cyanobacterial bloom locations in Kabetogama Lake, Voyageurs National Park (Minnesota, USA). Models include those using near-real-time environmental variables (readily available) and those using additional comprehensive variables (based on laboratory analyses). Comprehensive models (R2 = 0.87 MC; R2 = 0.86 MIX) explained more variability than the environmental models (R2 = 0.58 MC; R2 = 0.57 MIX). Although neither MIX model was a better fit than the MC models, the MIX models produced no false negatives in the calibration dataset, indicating that all observations above regulatory guidelines were simulated by the MIX models. This is the first known use of Virtual Beach software for a cyanotoxin mixture model, and the methods used in this paper may be applicable to other lakes or beaches.

Heterogeneity is a critical driver in rangeland ecosystems and can be used to direct and quantify management success across landscapes. Plant community dynamics and patterns are frequently examined in relation to herbivory, but most patterns are discussed either in a single dimension, or across species, but at small spatial scales within individual communities. Therefore, we designed a study to measure plant community spatial patterns across similar topographic position and soil type in pastures with three different herbivory intensities. We assessed plant community spatial patterns in the northern mixed-grass prairie near Streeter, ND, USA (46°45′N, 99°28′W) in pastures moderately or intensively grazed or non-grazed exclosures established for 25 years. Plant species composition and abundance were recorded along 50-m transects in three replicate pastures for each grazing intensity (n = 3) at mid-summer twice separated by 10 years. Fine and coarse-scale diversity were similar between the moderately and intensively grazed pastures and greater than the non-grazed exclosures in both years (p ≤ .05). Plant species composition was similar among the three grazing intensities and years. Plant community heterogeneity was highest for moderately grazed pastures followed by intensively and non-grazed exclosures respectively. Similarly, patch size was smallest for moderate pastures followed by intensive pastures and non-grazed exclosures for both years. However, while patch size in both moderate and intensive pastures was similar across years respectively, patch size in non-grazed exclosures increased over time. Land management activities varying the disturbance intensities or timing of disturbance can influence specific species composition and relative abundance among species groups. Grazing intensity influenced both fine- and coarse-scale plant community patterns and created different, but stable, plant community patch sizes over time. Based on these results, the ecological cost of inactivity in managing grasslands may have profound consequences on plant community stability and the wildlife that depend on them.

Inexpensive, accurate, and rapid measurements of sodicity are required to identify the restoration options for degraded sites. This study determined the spatial variability of the percent of ammonium acetate extractable Na (%Na), apparent electrical conductivity (ECa), pH1:1, elevation and topographic wetness index, and used this information to create %Na management zones. In an 8.1 ha North Dakota field that contained Natraquolls and Calciaquolls, 1088 soil samples from the 0–0.3 and 0.3–0.6 m were collected from a 12.2 by 12.2 m geo-referenced grid. At each grid point, the elevation and ECa was determined using a differential corrected global positioning system and EM38m, respectively. Soil samples were analyzed for the %Na, EC1:1, pH1:1, and soil dispersion. Exponential semi-variogram models explained 96.7% of the ln-transformed %Na data in the 0–0.3 m soil depth, and %Na was correlated to EC1:1 (r = 0.54), pH1:1 (r = 0.68), clay dispersion (r = 0.68), ECav (r = 0.49), and ECah (r = 0.57). Forward stepwise regression models based on elevation, EC1:1, pH1:1, and ECah explained 64 and 74% of the %Na variability in the surface 0.3 m and subsurface 0.3–0.6 m, respectively. Management zones were identified that reduced the %Na variability up to 82%.

The purpose of this study was to assess high school students' perceptions of nature and the amount of time they spend outdoors. More than 200 tenth graders from different demographic locations in Minnesota, USA were surveyed to understand their perceptions of nature, their attitude towards it, as well as to gauge what activities students were participating in when outdoors. Results indicate that regardless of demographics, students seem to define and perceive nature similarly. Further, the study also found that time spent on a computer or in front of the television has decreased but greater time is spent on personal electronic devices.

Wetland assessment has been shown to be an important tool in understanding the condition and function of the world’s wetlands, and use of muli-tiered assessment strategy has been recommended. In order to evaluate the performance of each tier of a multi-tiered wetland assessment strategy, we sampled 255 seasonally-ponded wetlands in the Missouri Coteau, the most wetland dense ecoregion in the Prairie Pothole Region. We assessed the condition of each study wetland using four sampling methods and models (tiers) of increasing levels of effort and complexity: (1) a level 1 assessment using the geographic information system-based Landscape Wetland Condition Analysis Model (LWCAM); (2) a level 2 assessment using the North Dakota Rapid Assessment Method (NDRAM); (3) a level 3- assessment using the vegetative-based Floristic Quality Index (FQI) and (4) a level 3 assessment consisting of a Hydrogeomorphic (HGM) Model functional assessment. We compared assessment tiers to determine how similar the different levels of assessment ranked sites either by condition or function. Both the NDRAM and FQI assessments, though very different in wetland characteristics assessed, provided similar condition rankings as the more intensive level 3 HGM assessment (89 and 90% similar, respectively). Additionally, the FQI was 86% similar to the level 2 NDRAM, indicating that these two assessment methods have utility in assessing wetlands similar to a HGM assessment. Information from this study can be used as a tool for determining need specific, financial, and time appropriate wetland sampling methods.

Kabetogama Lake in Voyageurs National Park, Minnesota, USA suffers from recurring late summer algal blooms that often contain toxin-producing cyanobacteria. Previous research identified the toxin microcystin in blooms, but we wanted to better understand how the algal and cyanobacterial community changed throughout an open water season and how changes in community structure were related to toxin production. Therefore, we sampled one recurring bloom location throughout the entire open water season. The uniqueness of this study is the absence of urban and agricultural nutrient sources, the remote location, and the collection of samples before any visible blooms were present. Through quantitative polymerase chain reaction (qPCR), we discovered that toxin-forming cyanobacteria were present before visible blooms and toxins not previously detected in this region (anatoxin-a and saxitoxin) were present, indicating that sampling for additional toxins and sampling earlier in the season may be necessary to assess ecosystems and human health risk.

In the northern Great Plains, a potential road dust abatement is the application of oil-well produced water, also known as “brine.” However, little is known about the effectiveness of brine or its potential impacts on dispersion of road materials and the creation of dusts. This study aimed to investigate how sodium adsorption ratios (SAR), electrical conductivity (EC), and Ca/Mg ratios of simulated and non-simulated brine influenced dispersive reactions of three mineralogically different gravel road fine fractions. Ca/Mg ratios had little to no significant influence on the outcome of dispersion. Irrespective of the SAR or clay mineralogy, a threshold EC of 4 dS m−1 was sufficient to control road fine fraction dispersion. Actual oil-well produced water effect on dispersion followed the same order as that treated by simulated solution and the dispersion value can be well-predicted from EC. This information is useful to managers, regulators, scientists, and industry professionals considering the use of brine as a road dust control abatement.

The purpose of this research was to understand how students in different demographics in the state of Minnesota understand and perceive concepts relating to food systems. Schools within the demographic categories of large metropolitan/inner city, urban cluster, and rural areas were chosen to determine if perceptions and knowledge of students were dependent on the demographic in which they lived. A total of 204 students were surveyed using a variety of types of questions to address research objectives. Results indicate that students have a general understanding of food production and where their food comes from, but as food sources become more complex or items are less common, students become confused. Food access did vary, where rural students used gas stations more than their urban counterparts. Large metropolitan/inner city adolescents had higher occasional use of farmer’s market/food stands which can be used as a way to start educational understanding about local foods. Students have a strong willingness to learn more about food systems and other environmental topics in school, but agree that they are not often receiving this interaction in the classroom. All demographics had low interest in local food and gardening, but rural students did have more access to these foods. Implications from this study can help researchers and educators understand students’ knowledge and perceptions about the food system, how they influence it, and how this changes across demographics.

Sodic soil remediation is an expensive, lengthy process during which producers need tools to demonstrate that sodium (Na+) remediation practices are improving soil health. The objective of this study was to determine if soil biological indicators can provide a short term assessment of the effectiveness of chemical management strategies used to remediate northern Great Plains sodium affected soils. This randomized complete block split-plot research experiment was conducted in a grassland which was converted to annual row crops. The soil at the site was an Exline (fine, smectitic, frigid Leptic Natrudolls). The experiment contained two drainage treatments (tile drained and no-drainage) and four chemical amendments (4.5 Mg ha−1 of gypsum, 9.1 Mg ha−1 of gypsum, 9.1 Mg ha−1 spent sugar beet lime, and a no amendment control). Base-line soil samples for biological assessment were collected in the fall of 2012 after tile drainage was installed. The sodium adsorption ratio (SAR) ranged from 0.4 to 16.7 with a range of electrical conductivity (EC) of 0.4–0.8 dS m−1. Gypsum and lime amendments were applied in 2013. Soil samples were collected for assessing soil health before and after application of amendments and throughout the growing season. This study utilizes a novel application of successional vector trajectories to compare shifts in measured soil health parameters associated with land use change and remediation of sodicity. Soil samples were analyzed for percent total soil carbon (C), nitrifier and denitrifier gene copies, soil enzyme assays (nitrate reductase, ammonia monooxegenase, urease, β glucosidase, alkaline phosphatase, arylsulfatase and fluorescein diacetate hydrolysis), EC, pH, SAR, and soil texture. Gene copies and enzyme activities were successfully used to differentiate between land uses and amendment applications. Ammonia oxidizing bacterial gene copies were higher where cropland was amended with gypsum. Successional vectors verified a significant shift in soil health due to land use change and amendment application. Gypsum applications reduced SAR, but increased soil EC. This work demonstrates that soil enzyme activities and gene copy numbers can be used to detect improvements in soil health.

Energy development in the Bakken and Three Forks formations of the USA has led to an increase in fugitive dust from unpaved roads. A dust abatement alternative that has been considered in this region is oil-well produced waters. The objectives of this study were to compare dust loading at sites abated with produced water to non-abated control sites and to determine if the elemental constituents in released dust are different compared to control roads. Three previously untreated unpaved roads were selected, and passive dust collectors were placed at 10, 20, 40, and 60 m from the road on the downwind side of the dominant prevailing wind in each mile section. Eighty-four days post-application, two sections treated with produced waters failed to reduce dust when compared to the controls. Dust elemental changes were found on two of the three roads. Elements that were found to have differences included Mo, Mn, Fe, As, Au, and Hg. Overall results indicated that oil-well produced water is not effective at controlling road dust. Results of this study are important to road managers who are contemplating the usage of produced waters to reduce dusts from unpaved roads.

Road dust impacts almost all terrestrial areas of the planet and may impact vegetation and nearby ecosystems. Therefore, research methods are needed for applying road dust in a controlled manner on targeted areas (e.g. plants). Three dust application methods, sifter, sieve, and sprayer, were investigated for their uniformity in applying dust in a 0.75 m × 0.75 m area. Within the treatment area 196, 37-ml cups were placed in a uniform fashion to collect dust applied at 15.8, 78.8, and 158 g. At the 15.8 and 78.8 g rates, the coefficient of uniformity for each method was >98% indicating a uniform amount of dust applied. At the 158 g rate, the sifter and sieve had coefficient of uniformities >95%, while the sprayer had a significantly lower (p

Restoring forb richness to the northern tallgrass prairie (U.S.A.) is often problematic. A potential solution is the establishment of native forb-seeded patches that can serve as colonization sites. This study was designed to determine the following: (1) the success at which native forbs sown in small patches can colonize the surrounding vegetation matrix and (2) whether soil amendments (C additions, P fertilization, and seed bank reduction) applied to the seeded sites can facilitate such colonization (patch quality). Colonization was investigated at (1) the immediate surrounding (1 m belt transect, BT) of the seeded sites and (2) in disturbed but not seeded patches located 3 m from the seeded site (out-plots). Soil amendments did not affect colonization, but native forb density in the BT and out-plots was correlated to the density of forbs in the seeded sites (r2 = 0.3, p < 0.01). Seeded native forb density in the out-plots was higher than in the adjacent BT (19 vs. 5 plants/m2), suggesting that competition from the matrix vegetation may be more important in forb colonization than distance from the source. Taller forbs with larger seeds showed advantages in colonization success. This study showed that the colonization of matrix vegetation with native forbs from seeded patches is a viable method for prairie reconstruction but requires the availability of disturbed sites. In most prairies, animal-generated soil disturbances are common. In their absence, disturbances of the vegetation matrix will need to be added to the management plan.

Questions How are plant species richness and diversity related to spatial autocorrelation under grazed and ungrazed conditions in grassland communities? Is spatial autocorrelation dissimilar within different plant communities? Location The grasslands of southeast North Dakota, USA. Methods The study was conducted during the summer of 2009 in six grasslands under different management (grazed vs ungrazed with fire) along a moisture gradient. Spatial autocorrelation at each site was measured along 50-m transects among three different landscape positions representing different moisture levels. Dissimogram multivariate analysis was used to measure the nugget, dissimilarity and patch diameter. Additionally, richness and Shannon diversity indices and nonmetric multidimensional scaling analysis were compared to the dissimogram results. Results Mean patch diameter was significantly higher in grazed mid-slope sites than in ungrazed sites. Spatial autocorrelation was not different between the landscape positions (higher, dry areas were not different from lower, mesic areas). However, plant species richness, diversity and community composition were found to be different between landscape positions and management, with key differences in the presence of certain invasive species. Conclusions Disturbance and moisture level were reflected differently in the spatial autocorrelation analysis compared to the richness, diversity and ordination analyses. This indicates that disturbance and management impacted spatial autocorrelation separate from plant community composition and species diversity. This also highlights changes in the plant community caused by different management actions and the spread of invasive species.

Associations between soil properties and Pythium groups on soybean roots were investigated in 83 commercial soybean fields in North Dakota. A data set containing 2877 isolates of Pythium which included 26 known spp. and 1 unknown spp. and 13 soil properties from each field were analyzed. A Pearson correlation analysis was performed with all soil properties to observe any significant correlation between properties. Hierarchical clustering, indicator spp., and multi-response permutation procedures were used to identify groups of Pythium. Logistic regression analysis using stepwise selection was employed to calculate probability models for presence of groups based on soil properties. Three major Pythium groups were identified and three soil properties were associated with these groups. Group 1, characterized by P. ultimum, was associated with zinc levels; as zinc increased, the probability of group 1 being present increased (α = 0.05). Pythium group 2, characterized by Pythium kashmirense and an unknown Pythium sp., was associated with cation exchange capacity (CEC) (α

The Bakken region of western North Dakota and Montana from January 2012 to December 2013 saw an increase of 3368 oil wells, causing a major increase in road dust emissions. A portion of the energy extraction in the Bakken occurs in the wetland rich Prairie Pothole Region, and there is little information on gravel road dust emissions or the ecological impacts. The objectives of this study were to (1) estimate surface loading of gravel road dust during different times of year and at different distances from the road, (2) evaluate dust loading effects on surface water quality, and (3) evaluate the impact of dust deposition on wetland soils. Ten wetlands were tested in the energy impacted area and ten in an adjacent area without energy development. There was a 355 % increase in dust loading 10 m from the road in the energy impacted area compared to an area without energy development; meanwhile, there was only a 46 % increase in dust loading 40 m from the road. This loading resulted in an annual deposition of 647 g/m2 of gravel road dust close to the road. However, the effect of dust loading on the water quality and soils of wetlands was minimal when compared to wetlands not impacted by increased gravel road dust. The finding of minimal effect on wetland resources from increased road dust fills a knowledge gap in the Bakken on how energy development alters the environment.

Off-leash dog parks are very popular locations that allow pets to freely exercise and eliminate wastes in a controlled environment. Although dog park rules require that solid waste be removed by the pet’s owner, urine-borne constituents in dog-park soils have received little attention. This study focused on the soils within two small-dog, off-leash dog parks in Fargo, North Dakota (USA) with the objective to better understand the concentration and distribution of extractable NH4-N, NO3-N, PO4, soluble salts, and pH values in surface soils (0–10 cm) within these two dog parks. Concentrations of soil variables varied widely within each park and were distributed as both gradient and ‘hot-spots.’ The geospatial model types for each soil parameter were more dependent on park than on the constituents themselves. Flow accumulation was correlated with both nitrate-N and P but due to the lack of topography at these parks the flow accumulation was not helpful in describing most of the soil constituents. The results from this project indicate that location of parks, daily/annual use of parks, flow accumulation, and location of park entries may all influence the concentration and distribution of urine-borne constituents.

Meehan, M. A., DeKeyser, E. S., Sedivec, K. K. and Norland, J. E. 2012. Nutritional composition of Sprengel's sedge ( Carex sprengelii ). Can. J. Plant Sci. 92: 867–871. Sprengel's sedge (Carex sprengelii) has been documented as a primary graminoid species in riparian woodlands and forested areas of the northern Plains. Currently, there is no documentation of the nutrient content of Sprengel's sedge. The objective of this study was to determine the nutritional value of Sprengel's sedge of riparian woodlands in eastern North Dakota. Plants were clipped to 2.5 cm from the soil surface at 2-wk intervals during the growing seasons of 2009 and 2010. Multiple whole-plant samples were collected from five randomly selected sites at two different locations during each collection period. Plant tissue was analyzed for crude protein (CP), acid detergent fiber, neutral detergent fiber, in vitro organic matter digestibility (IVOMD), calcium, and phosphorus. The CP concentrations declined from over 20% in May to under 10% in October. Sprengel's sedge, based on IVOMD, met energy requirements for a 550 kg lactating cow early in the growing season; however, as the growing season progressed it was unable to meet energy requirements. Irrespective of year, Sprengel's sedge maintains a high CP level throughout a typical grazing season; however, digestible energy becomes deficient. Grazing strategies that promote spring and early summer grazing or supplementation of a high-energy feed source to compensate for the decrease in energy are recommended.

Understanding the knowledge and perceptions of adolescents is an integral part of creating better curriculum and education materials in the natural sciences. This study explores the challenges of working with a protected population in a public school setting in terms of Institutional Review Board standards, the complex process of a researcher gaining access to the public schools, and the difficulty in attaining both parental and youth consent. In total 39 school districts throughout the state of Minnesota, USA, were invited to participate in the study; school districts were contacted from three demographics including (1) large metropolitan/inner city, (2) urban cluster, and (3) rural. Overall, securing participation among all demographics was challenging, though rural populations were the easiest when compared with the other demographics. Differences between groups were related to how gatekeepers granted approval. More gatekeepers exist in larger school districts and areas with greater populations. The ongoing complexities of gaining access to adolescents in public school settings may cause problems in determining what students actually know about the natural sciences and could hinder creation of appropriate education materials based on this information. The information in this study can be used by researchers, extension professionals, and educators to better understand how to navigate the current challenges that exist when researching a protected population in public schools.

In the northern Great Plains (United States), sites with less than 20% of native species are difficult to restore. We have experimented with a restoration method that shows some promise. It consists of systematically installing simulated small-scale patches (8.0 m2 in size) over 25% of an old field and then seeding these patches with native species. The working hypothesis is that these patches will generate a constant source of propagules which in time will lead to increases in native species diversity within the surrounding grass matrix. The objective of this paper was to determine whether soil amendments should be used to facilitate the establishment and persistence of native species (primarily forbs) within these patches. We seeded the patches with a mixture of native grass and forb species and applied four soil treatments: P fertilization, C additions, C + P, and a control (no amendments). Results for the first 5 years were as follows: (1) seeded forb richness was mostly unaffected by soil amendments; (2) seeded and nonseeded forb biomass and density were substantially reduced by C additions, whereas they were unaffected or increased under P additions; (3) both seeded and non-native grass biomass substantially increased with C additions; and (4) there was an inverse relationship between native seeded forbs and non-native grass biomass. Our conclusions are that: (1) P amendments are a potential tool for enhancing native seeded forb biomass in simulated small-scale disturbance patches; and (2) C additions, although enhancing seeded grass biomass do not reduce the biomass of non-native grasses.

The Ecological Area-wide Management Leafy Spurge, or TEAM Leafy Spurge, began collecting and redistributing flea beetles (Aphthona spp.) to research/demonstration sites and landowners throughout the Little Missouri River drainage basin to control leafy spurge in 1998. A study to evaluate the change over time of leafy spurge (Euphorbia esula L.) phytosociological characteristics following release of flea beetles was initiated in 2002 on leafy spurge–infested pasture and rangeland in the Little Missouri River drainage of Montana, North Dakota, South Dakota, and Wyoming. A total of 292 flea beetle release sites were analyzed in June and July 2002 and 2003 for leafy spurge stem density, foliar cover, flea beetle density, and vegetation composition. Leafy spurge stem density suppression was evident at 91% of the study sites. On two-thirds of the study sites stem density was reduced from greater than 100 stems·m−1 to less than 25 stems·m−1. Leafy spurge foliar cover was less than 5% on approximately two-thirds of the flea beetle release sites and less than 25% on over 90% of the release sites. Area of observed leafy spurge suppression ranged from 0 m2 to 30000 m2. Approximately 40% of the release sites had leafy spurge suppression ranging from 1000 m2 to 5000 m2, and 14% of the release sites had greater than 10000 m2 of leafy spurge control. Plant community composition following leafy spurge suppression was characteristic of native plant communities that had not been burned or grazed. Flea beetles effectively reduced leafy spurge stem density and cover in 4–5 yr across a variety of locations and corresponding environmental conditions, both within the Little Missouri River drainage and in selected nearby locations.

Landscapes with structural heterogeneity or patchiness can support diverse and stable wildlife populations. Visual obstruction methods (i.e., Robel pole and Nudd's coverboard) are common and useful techniques for quantifying vegetation structure; however, both rely on ocular estimations, which can be highly variable between observers. Our objectives were to 1) compare measurement and observer variation for visual obstruction among the two standard methods and the digital image method we developed using a digital camera; and 2) compare the performance of the Robel pole and digital image to estimate standing crop. The mean variation across the five observers using the digital image method (6.8%) was significantly lower (P

Hyperspectral 1-m-resolution remote sensing has the potential to reduce the time spent sampling and reduce spatial sampling errors found in traditional forage nutritive analysis over large areas. The objective of this study was to investigate if 1-mresolution hyperspectral techniques are useful tools to provide reliable estimates of forage nitrogen (N), phosphorus (P) and neutral detergent fiber (NDF) in Yellowstone National Park. The vegetative communities investigated varied in the amount of canopy coverage and species diversity, and ranged from xeric, semiarid environments to mesic, wetland/riparian environments. A large number of simple ratio-type vegetation indices (SRTVI) and normalized difference-type vegetation indices (NDTVI) were developed with the hyperspectral dataset. These indices were regressed against N, P, and NDF values from ground collections. We found that 1) there were strong linear relationships between selected SRTVI and N (R 2 ¼ 0.7), P (R 2 ¼ 0.65), and NDF (R 2 ¼ 0.87) nutritive values on an area basis (g � m � 2 ); and 2) there were no strong linear relationships (R 2 , 0.3) between a variety of SRTVI and NDTVI and N, P, and NDF on a dry matter basis (g � g � 1 3 100). The lack of relationship is related to 1) the highly variable relationship between the dry matter biochemical signal and total plant biomass and water content and 2) the weakening of the biochemical signal from exposed soil in low-canopy situations, from nonphotosynthetic vegetation (bark, stems, and litter), and from different plant species.

This study was designed to determine the utility of a 1-m-resolution hyperspectral sensor to estimate total and live biomass along with the individual biomass of litter, grasses, forbs, sedges, sagebrush, and willow from grassland and riparian communities in Yellowstone National Park, Wyoming. A large number of simple ratio-type vegetation indices (SRTVI) and normalized differencetype vegetation indices (NDTVI) were developed from the hyperspectral data and regressed against ground-collected biomass. Results showed the following: 1) Strong relationships were found between SRTVI or NDTVI and total (R 2 ¼ 0.87), live (R 2 ¼ 0.84), sedge (R 2 ¼ 0.77), and willow (R 2 ¼ 0.66) biomass. 2) Weak relationships were found between SRTVI or NDTVI and grass (R 2 ¼ 0.39), forb (R 2 ¼ 0.16), and litter (R 2 ¼ 0.51) biomass, possibly caused by the mixture of spectral signatures with grasses, sedges, and willows along with the variable effect of the litter spectral signature. 3) A weak relationship was found between sagebrush biomass and SRTVI or NDTSI (R 2 ¼ 0.3) that was related to interference from sagebrush photosynthetic or nonphotosynthetic branch and twig material, and from the indeterminate spectral signature of sagebrush. This study has shown that hyperspectral imagery at 1-m resolution can result in high correlations and low error estimates for a variety of biomass components in rangelands. This methodology can thus become a very useful tool to estimate rangeland biomass over large areas. Resumen

We developed a forage allocation model using a deterministic, linear optimization module in a commercially available spreadsheet package to help resource managers in Theodore Roosevelt National Park (TRNP), North Dakota determine optimum numbers of four ungulate species, bison (Bison bison), elk (Cervus elaphus), mule deer (Odocoileus hemionus), and feral horses, in the Park. TRNP staff actively managed bison, elk, and feral horse numbers within bounds suggested by our model from 1983 to 1996. During this period, we measured vegetation at 8 grassland and 12 wooded sites at 1-3 year intervals to determine if model solutions were appropriate for maintaining stable conditions in important plant communities in the Park. The data we recorded at these sites indicated minimal change in plant communities from 1983 to 1996. Changes in most vegetation categories that we expected when animal numbers exceeded model optimums for short periods (decreases in coverage/stem numbers of palatable plant species, increases in bare ground or unpalatable plant species) did not occur consistently under high or low precipitation conditions. The lack of sensitivity of our model to decreases in overall production of palatable plant species that occurred due to drought, fire, expansion of black-tailed prairie dog (Cynomys ludovicianus) colonies, and the spread of leafy spurge (Euphorbia esula) in areas of the Park where we did not have monitoring sites suggested that the model under-estimated the total number of ungulates that the Park could support. Management for population levels of ungulates defined by the model probably led to over protection of common plant communities and insufficient protection of rare plant communities. Detecting changes in rare plant communities could have been accomplished by re-designing our vegetation monitoring program, but changing emphasis to protection of rare plants would have likely promoted under use of grazing-tolerant habitat types, dissatisfaction in tourists visiting the Park to see large mammals, and large increases in cost and intrusiveness of management activities such as fencing and control of ungulate populations. The model was a flawed representation of grazing dynamics in TRNP, but we believe it succeeded in making management personnel aware of the biological constraints they face when making management decisions.

Niche relationships and diet overlaps were compared among elk (Cervus elaphus), bison (Bison bison), bighorn sheep (Ovis canadensis), mule deer (Odocoileus hemionus), and pronghorn antelope (Antilocapra americana) between 1967–1970 and 1986–1988, a period when total ungulate numbers nearly tripled on Yellowstone's northern range. Ungulate species ratios on Yellowstone's northern winter range during the latter period were 100 elk : 10 mule deer : 3 bison : 2 pronghorns : 1 bighorns. Elk numbers were positively correlated to bison, mule deer, and pronghorn numbers (r2 = 0.76, 0.97, and 0.48, respectively, P

This project was designed to determine the optimum population size for bison in the Theodore Roosevelt National Park (TRNP) by fulfilling the following objectives: 1. Delineate primary and secondary bison ranges; 2. Determine forage productivity for major range sites within primary and secondary use areas; 3. Determine the general seasonal food habits of bison in TRNP; 4. Determine range condition under present population density of bison and the maximum carrying capacity of primary use areas; and 5. Integrate range condition and carrying capacity estimates with management priorities for bison on the TRNP.