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  • ItemOpen Access
    LTER: long term ecological research network
    (Colorado State University. Libraries, 2005) Yonker, C. M., author; Kaplan, N. E., author; Kelly, E. F., author; SGS-LTER, Colorado State University, publisher
    The Long Term Ecological Research (LTER) Network is a collaborative effort involving more than 1800 scientists and students investigating ecological processes over long temporal and broad spatial scales. Each LTER site encompasses unique ecosystems and research approaches, investigators, students and management systems. Each of the 26 sites works as part of the Network sharing expertise, data and a common mission. Poster presented at the 7th Shortgrass Steppe Symposium held in Fort Collins, Colorado on 1/14/05.
  • ItemOpen Access
    A team approach to data synthesis: the playbook for creating a centralized, dynamic, and sustainable ANPP database
    (Colorado State University. Libraries) Laney, Christine, author; Cushing, Judith B., author; Muldavin, Esteban, author; Vanderbilt, Kristin, author; Kaplan, Nicole E., author; Zeman, Lee, author; Milchunas, Daniel, author; Leroy, Carri, author; Kruger, Judith, author; Gao, Jincheng, author; Ramsey, Ken, author; Mallett, Juli, author; SGS-LTER, Colorado State University, publisher
    The Grasslands Data Integration (GDI) project has brought together ecologists, information managers and computer scientists to address the interdisciplinary challenges of integrating ANPP data from multiple sources. In this poster we present 1) the necessity to coordinate expertise and information to integrate ANPP data and metadata from five national and international grassland LTER sites, 2) the data model we designed to archive and serve the data, and 3) analysis planned for the future. This collaboration is an example of how professionals with inter-related work experience build a community of experts and a successful data product for the LTER (Baker and Millerand 2007).
  • ItemOpen Access
    Inter-annual differences in abundance of thirteen-lined ground squirrels (Spermophilus tridecemlineatus) in Colorado Shortgrass Steppe
    (Colorado State University. Libraries, 1999) Stapp, Paul, author; Hanni, David, author; Lindquist, Mark, author; SGS-LTER, Colorado State University, publisher
    We live-trapped thirteen-lined ground squirrels (Spermophilus tridecemlineatus) on three grassland and three saltbush-dominated sites in June and July 1999 to estimate population densities in representative vegetation types in shortgrass steppe, and to describe changes in population structure and body weight during their summer active period. We also compared population densities in 1999 to estimates from 1995, the last time that ground squirrel populations were surveyed on the SGS-LTER site in north-central Colorado. As in 1995, most squirrels captured in June 1999 were adults; the near absence of juveniles in June 1999 compared to the earlier study suggested that reproduction was delayed this year. Juveniles comprised > 70% of individuals captured in both habitats in July 1999, and were especially numerous on grassland sites. However, in contrast to 1995, when squirrels much more common in saltbush habitats, squirrels were significantly (2-3X) more abundant on grassland webs in 1999. The difference in population densities between habitats in 1995 vs. 1999 was unexpected because both years had similarly high early-season precipitation, and presumably, similar vegetation. Moreover, there were no consistent differences in the abundance of arthropod prey between years that could readily explain the differences in squirrel abundance. Additional long-term studies of ecology and population dynamics of thirteen-lined ground squirrels in shortgrass steppe will be necessary to identify the factors that determine patterns of abundance of this critical species over time.
  • ItemOpen Access
    Plague outbreaks in prairie-dog colonies associated with El Niño climatic events
    (Colorado State University. Libraries, 2003) Stapp, Paul, author; Antolin, Michael F., author; Ball, Mark, author; SGS-LTER, Colorado State University, publisher
    Plague (Yersinia pestis) was introduced to the western U.S. in the mid-20th century and is a significant threat to the persistence of black-tailed prairie dog (Cynomys ludovicianus) populations. The social, colonial habits of prairie dogs make them particularly susceptible to plague, and many flea species, including known carriers of plague, are associated with prairie dogs or their extensive burrow systems. Mortality during plague epizootics, or outbreaks, is nearly 100% (Cully and Williams 2001; J. Mammal. 82:894), resulting in the extinction of entire colonies. In northern Colorado, prairie dogs exist in metapopulations (Roach et al. 2001, J. Mammal. 82:946), in which colonies naturally isolated by topography, soils and vegetation are connected by dispersal. Dispersal of either infected prairie dogs or plague-resistant reservoir species is hypothesized to spread plague among colonies. Plague outbreaks therefore may disrupt the dynamics of prairie-dog metapopulations and affect regional persistence. In the context of a century of past eradication efforts that have drastically reduced prairie-dog numbers, and increasing agricultural and urban development, plague represents a relatively new and unique threat to prairie dogs and the species that are closely associated with them. Poster presented at the 6th SGS Symposium held on 1/10/03.
  • ItemOpen Access
    An IM toolbox for the present and future to support data synthesis activities
    (Colorado State University. Libraries, 2007) Zeimet, Adam, author; Beer, Dianne, author; Norman, John, author; Kaplan, Nicole, author; Flynn, Bob, author; SGS-LTER, Colorado State University, publisher
    This poster displays four examples of topics and tools currently being implemented and developed by information management staff at the Shortgrass Steppe LTER, across the LTER Network and within USDA Agricultural Research Service (ARS). These tools are necessary in order to synthesize similar data sets from different researchers, agencies, and institutions. These tools were designed provide to support to Principal Investigators, educators, students, and policy makers that need to synthesize information to make better decisions about planning their research, coursework and land management strategies. The four areas to be presented are Geographical Information Systems (GIS) and Remote Sensing, standardization of metadata using Ecological Metadata Language (EML), integration of relational database management systems for different agencies, and the creation of useful dynamic web pages. GIS and Remote Sensing are powerful tools that allow researchers to analyze, model, and predict ecological factors and outcomes that shape the shortgrass steppe by integrating spatial and non-spatial data collected at the field site. EML consists of a number of modules that define an extensible mark-up language (XML) that creates a standard syntax for ecological metadata. This concept allows for sharing of standard metadata and data across not only the LTER Network, but throughout the broader ecological community. SGS is researching new database technologies to managing the growing amount of standard non-spatial data from the ARS and LTER as well as GIS and Remote Sensed data. This also will address the need for multi-user data access and database integration with the SGS website. An SGS Website was launched 8 years ago to provide general site information as well as detailed research information. The web site will be enhanced over the next year to improve query tools, submit metadata online, improve integration with various ecological research databases, and implement the EML standards.
  • ItemOpen Access
    Mediation of spatial organization in the swift fox, Vulpes velox
    (Colorado State University. Libraries, 2005) Dabelsteen, Torben, author; Darden, Safi K., author; SGS-LTER, Colorado State University, publisher
    Animals communicate in a network of individuals. Acoustic, chemical, and visual signals can operate in this network to convey information about a signaller's identity, behaviour, physiological state and location. Poster presented at the 7th Shortgrass Steppe Symposium held in Fort Collins, Colorado on 1/14/05.
  • ItemOpen Access
    Shortgrass Steppe Long Term Ecological Research
    (Colorado State University. Libraries, 2005) Moore, J. C., author; Lauenroth, W. K., author; Stapp, P. A., author; Burke, I. C., author; Kelly, E. F., author; Antolin, M. F., author; Pielke, R. A., author; Paustian, K. H., author; Parton, W. J., author; Mosier, A. R., author; Milchunas, D. G., author; Detling, J. K., author; Morgan, J. A., author; SGS-LTER, Colorado State University, publisher
    The shortgrass steppe (SGS) Long Term Ecological Research (LTER) site is part of a network of long-term research sites supported by the National Science Foundation. The network consists of 26 sites representing diverse ecosystems and research emphases, yet maintaining a common mission and sharing expertise and data. We assert that the ecological structure and function of the shortgrass steppe is governed by climate, human use, natural disturbance, biota and physiography. Our conceptual framework, right, depicts the relationship between these factors and our core research areas. Poster presented at the 7th Shortgrass Steppe Symposium held in Fort Collins, Colorado on 1/14/05.
  • ItemOpen Access
    Plant community changes associated with prairie dog usage of a suburban remnant of the Shortgrass Steppe
    (Colorado State University. Libraries, 2005) Hartley, Laurel, author; SGS-LTER, Colorado State University, publisher
    Dr. Detling and others have documented changes in plant communities in the mixed grass prairie caused by the herbivory of the Black-tailed prairie dog, Cynomys ludovicianus. Canopy height, litter cover, and graminoid cover relative to forbs decrease, while species diversity, nitrogen mineralization, and plant shoot protein increase. The shortgrass steppe is significantly different from the mixed grass prairie: precipitation is lower, the grasses are dominated by the drought resistant (hence grazing resistant) grass blue grama, and prairie dog colonies are killed off periodically by plague. Additionally, in the suburban setting, large herbivores are excluded, habitat is fragmented, human interaction is increased, and there is an increased presence of non-native species. Currently, SGS-LTER graduate students are researching changes in plant communities in response to prairie dog herbivory on the shortgrass steppe at the SGS-LTER site and Pawnee National Grasslands in order to compare to the results from the mixed grass prairie. In this study, we are tracking changes in the plant community in response to prairie dog herbivory on a suburban shortgrass steppe remnant which we hope to compare to the results from the SGS-LTER/PNG and the mixed grass prairie. We hope to provide useful data for local agencies creating management plans for natural areas along the Front Range.
  • ItemOpen Access
    Long-term ecological research on Colorado Shortgrass Steppe
    (Colorado State University. Libraries, 2012) Milchunas, Daniel G., author; Lauenroth, William K., author; Knapp, Alan K., author; Klein, Julia A., author; Conant, Richard T., author; Burke, Ingrid C., author; Brown, Cynthia S., author; Webb, Colleen T., author; Augustine, David J., author; Angert, Amy L., author; Kelly, Eugene F., author; Kaplan, Nicole E., author; Derner, Justin D., author; Antolin, Michael F., author; Moore, John C., author; Blumenthal, Dana M., author; Wallenstein, Matthew D., author; von Fischer, Joseph C., author; Stapp, Paul, author; Paustian, Keith H., author; Parton, William J., author; Morgan, Jack A., author; SGS-LTER, Colorado State University, publisher
    Poster presented at the LTER All Scientists Meeting held in Estes Park, CO on September 10-13, 2012.
  • ItemOpen Access
    Livestock exclusion increases the spatial heterogeneity of vegetation in the Shortgrass Steppe
    (Colorado State University. Libraries, 2001) Adler, Peter, author; SGS-LTER, Colorado State University, publisher
    Ecologists have collected extensive information on how various factors affect the MEAN values of key response variables, but typically ignore how spatial distribution is affected. Describing spatial heterogeneity is important because 1) pattern may affect process and 2) the identification of previously unrecognized patterns generates new hypotheses.
  • ItemOpen Access
    Database tools for ecological data integration and synthesis
    (Colorado State University. Libraries, 2003) Cushing, Judy, author; Vanderbilt, Kristin, author; Ramsey, Ken, author; Nadkarni, Nalini, author; Kaplan, Nicole, author; Finch, Michael, author; Fiala, Anne, author; Melendez-Colom, Eda, author; SGS-LTER, Colorado State University, publisher
    The challenge: 1. To synthesize across research sites syntactically disparate, but thematically similar, data. 2. To efficiently perform cross-site synthesis, using new informatics tools that exploit database component technology. 3. To aid analysis of ecological data through visualization tools that take advantage of informatics-processed data.
  • ItemOpen Access
    Recreational shooting: how are sites selected and what are the implications for Burrowing Owl (Athene cunicularia) reproduction?
    (Colorado State University. Libraries, 2001) Van Horne, Beatrice, author; Woodard, Jason D., author; SGS-LTER, Colorado State University, publisher
    Declines in burrowing owl populations are inextricably linked to human activity and associated disturbances. Habitat loss and rodent control programs are the primary cause of observed declines (Butts 1973). Recreational shooting, harassment, and other human disturbances may exacerbate this decline by promoting mortality and nest failure in local populations. The extent and magnitude of these effects, however, remain unknown (Haug et al. 1993, Holroyd 1998).
  • ItemOpen Access
    Through the looking glass: what do we see, what have we learned, what can we share? Information management at the Shortgrass Steppe Long Term Ecological Research site
    (Colorado State University. Libraries, 2009) Zeimet, Adam, author; Beer, Dianne, author; Norman, John, author; Bennett, Christopher W., author; Flynn, Bob, author; Stafford, Susan G., author; Kaplan, Nicole E., author; SGS-LTER, Colorado State University, publisher
    This poster displays the development of a successful information management system at a Long Term Ecological Research (LTER) site that has a rich history of data collection and management. Over sixty years of data from three separate projects are incorporated into the Shortgrass Steppe (SGS) LTER information management system and databases. People with different strengths and expertise ranging from clerical administrator, programmer, to ecologist, have filled the role of Information Manager (IM) at the SGS-LTER. Today the information management needs of the SGS are provided by a team of IMs with various levels of expertise in a wide variety of domains from information technology administration to education and outreach. It is critical for IMs at any long-term research site to understand how information and data were managed in the past and what recent changes have been added to the system, in order to effectively implement a management plan for the future. We are able to evaluate the effectiveness of different approaches to information management and have a commitment to share our successes with the information management community.
  • ItemOpen Access
    A multi-scale assessment of beetle diversity and landscape properties
    (Colorado State University. Libraries, 1999) Wiens, John A., author; Hoffman, Aaron L., author; SGS-LTER, Colorado State University, publisher
    The issue of scale is important in ecology. Many studies have indicated that ecological patterns can vary with the grain and extent of the study, and thus it is difficult to extrapolate from fine to coarse scales. Furthermore, habitats are generally not homogenous, so interactions between an organism and its environment, as well as the scale at which they are examined, are primary factors underlying the patterns or processes being studied. This study has many facets, but we are particularly interested in how spatial patterns of beetle species richness and environmental variables change with scale. Other questions address whether there are spatial scales where correlations between beetle abundance and environmental measures peak? Identifying such scales should provide insights to the processes responsible for the observed patterns.
  • ItemOpen Access
    Species interactions across three trophic levels: Cynomys ludovicianus colonies increase floral visitation by insects
    (Colorado State University. Libraries, 2005) Hardwicke, K. B., author; Detling, J. K., author; SGS-LTER, Colorado State University, publisher
    Poster presented at the 7th Shortgrass Steppe Symposium in Fort Collins, Colorado on 1/14/05.
  • ItemOpen Access
    The influence of prey use and habitat on burrowing owl (Athene cunicularia) reproduction
    (Colorado State University. Libraries, 2001) Van Horne, Beatrice, author; Woodard, Jason D., author; SGS-LTER, Colorado State University, publisher
    Food, competition, and predation dictate habitat use (Schmutz et al. 1991) and ultimately reproduction. Avian reproduction is frequently food-limited (Wellicome 2000), and predation is the primary cause of nest failure (Martin 1993). Selection of prey and habitat features which minimize these effects should therefore enhance reproduction. We examined this issue using the Burrowing Owl, a declining species of the Great Plains.
  • ItemOpen Access
    GIS data and tools available at SGS-LTER
    (Colorado State University. Libraries, 2005) Kaplan, N. E., author; Flynn, R. L., author; SGS-LTER, Colorado State University, publisher
    Poster presented at the 7th Shortgrass Steppe Symposium held in Fort Collins, Colorado on 1/14/05.
  • ItemOpen Access
    Colorado Front Range GK12 connecting kids and ecology — teachers and researchers
    (Colorado State University. Libraries, 2005) Seemueller, Carol, author; Quirk, Meghan H., author; Moore, John C., author; Hartley, Laurel M., author; SGS-LTER, Colorado State University, publisher
    The Colorado Front Range GK12 project is a collaborative effort of Colorado State University, the University of Northern Colorado, Weld County School District 6, and Poudre School District.
  • ItemOpen Access
    Two years of carbon dioxide enrichment on the Shortgrass Steppe of Colorado
    (Colorado State University. Libraries, 1998) Ojima, D. S., author; Parton, W. J., author; Milchunas, D. G., author; Mosier, A. R., author; LeCain, D. R., author; Morgan, J. A., author; SGS-LTER, Colorado State University, publisher
    This study assessed how doubling the CO2 concentration over present levels affects the growth and physiology of shortgrass steppe vegetation in eastern Colorado. In March, 1997, six open-top chambers (OTCs) were installed on native shortgrass steppe in NE Colorado, USA. Three grass species make up about 88% of the above-ground biomass of this ecosystem; Bouteloua gracilis (C4), Pascopyrum smithii (C3) and Stipa comata (C3). More than 20 other grass and forb species also occur here. CO2 was injected into three OTCs to raise the concentration to 720 ppm, approximately twice that in the three ambient chambers. Three non-chambered plots were established to evaluate chamber effects. The air temperature in the chambers averaged 2° C warmer than outside. During 1997 and 1998 significant chamber and CO2 effects were detected. Averaging over the two years, above-ground production in the ambient chambers was 22% greater than that in unchambered plots, probably due to warmer spring temperatures in the chambers. Production under elevated CO2 averaged 35% greater than that in ambient OTCs. Significant growth increases occurred for both C3 and C4 grasses and forbs in 1998. These CO2 -induced growth increases were primarily due to improved water status. Soil water content was often higher in elevated CO2 chambers. Leaf water potentials were generally higher in plants grown at elevated CO2 compared to ambient chambers. Leaf intercellular CO2 photosynthesis response curves indicated neither P. smithii nor B. gracilis leaves were saturated with CO2 at 360 ppm. Photosynthetic capacity of both species was reduced in plants grown at elevated CO2, although this response was much stronger in the the C3 species, P. smithii. Results suggest that future CO2 enrichment will lead to growth enhancements in both C3 and C4 grasses of the shortgrass steppe.
  • ItemOpen Access
    Black-tailed prairie dog mounds: do they contribute to plant species diversity and nitrogen cycling?
    (Colorado State University. Libraries, 2001) Detling, J. K., author; Farrar, J. P., author; SGS-LTER, Colorado State University, publisher
    Soil mounds around burrows are natural disturbances in plant communities where prairie dogs (Cynomys spp.) occur. We hypothesized that one or more sub-dominant plant species are more abundant on black-tailed prairie dog (C. ludovicianus) mounds than on inter-mound areas or off-prairie-dog-town areas, and that soil mixing results in enhanced N-mineralization which increases N-content of plants growing on mounds. During summer 2000, we measured plant cover and biomass by species in on-mound, inter-mound, and off-town plots on three active prairie dog towns in each Texas, Colorado, and Montana. In Montana and Colorado, Solanum triflorum was found only on mounds, and Sphaeralcea coccinea was more frequent on prairie dog mounds than on inter-mound and off-town areas. In Texas, Achillea millefolium and Amaranthus blitoides was found only on prairie dog mounds, and Hoffmanseggia glauca was more frequent on mounds than on inter-mound and off-town areas. Biomass of grasses increased from on-mound to off-town sites while biomass of most forbs decreased. Plant nitrogen concentration showed a general decline from mounds to off-town areas. These findings support the hypothesis that soil disturbance caused by C. ludovicianus during construction and maintenance of their mounds contributes to plant species diversity and enhanced N-mineralization in grasslands.