Presentations

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https://hdl.handle.net/10217/195555

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Open 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.
Open 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).
Open 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.
Open Access
Arthropod diversity and abundance on a suburban remnant of the Shortgrass Steppe
(Colorado State University. Libraries, 2005) Hartley, Laurel, author; SGS-LTER, Colorado State University, publisher
Arthropod censuses are recorded on the Shortgrass Steppe Long Term Ecological Research site and Pawnee National Grasslands as a part of long term ecological monitoring. As the front range becomes developed, remnants of the shortgrass steppe become surrounded by human habitation. Subsequently there are increased efforts to control "pest" insect species, an increase in water availability, changes in insect food sources, and changes in predator species. These environmental changes are likely to affect arthropod communities. Long term monitoring of arthropod communities on a remnant shortgrass steppe enclosed by development may provide baseline data useful for local agencies creating management plans for natural areas along the front range.
Open Access
Arthropod studies on the Shortgrass Steppe LTER: past, present and future
(Colorado State University. Libraries, 2000) Hartley, Laurel M., author; Kaplan, Nicole E., author; Lindquist, Mark D., author; Stapp, Paul, author; SGS-LTER, Colorado State University, publisher
Arthropods play important roles in the ecology of shortgrass steppe as consumers, prey and detritivores. Here we describe past, ongoing, and future studies of arthropods conducted as part of the Shortgrass Steppe (SGS) LTER project in north-central Colorado. Our goals are to increase awareness of our arthropod research and existing datasets, and to identify opportunities for collaboration and cross-site comparisons with LTER researchers. Arthropods have been the focus of much short-term comparative and experimental research on the site, but we know of only two long-term studies. Since 1995, insects and spiders have been sampled monthly during summer (May- September) in live pitfall traps along a 1-km transect spanning a representative topographical gradient (catena). This project continues research conducted by other SGS-LTER scientists from 1990-1994 to investigate spatial dynamics of darkling beetle (Tenebrionidae) populations. A second project initiated in 1998 involves monthly summer sampling of macroarthropods in small pitfall grids in grassland and saltbush vegetation. This study was implemented to track changes in relative abundance of arthropod prey, and grids are located on trapping webs used for rodent population studies. In addition, we maintain on-site a small but growing reference collection of representative arthropods, which is mostly used to train field assistants and support other research projects. Poster presented at the Ecological Society of America Annual Meeting held in Snowbird, Utah.
Open 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.
Open 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.
Open 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.
Open Access
Dynamics of exotic species and their establishment in the Pawnee National Grasslands
(Colorado State University. Libraries, 2000) Lauenroth, William K., author; Betz, Dani-Ella, author; SGS-LTER, Colorado State University, publisher
We investigated the distribution of plant species in the shortgrass steppe to determine if the roadsides were acting as corridors, increasing the susceptibility of the open steppe to exotic species establishment. We surveyed 45 paired roadside and open steppe sites and found few exotic species in the the open steppe (.36/m2), whereas the roadsides contained significantly more (5.42/m2). We examined the soil seed bank along a transect from roadsides to 25 meters into the open steppe to investigate the range of seed dispersal and abundance of roadside exotic seeds. We found that a significantly greater number of exotic seeds in the roadsides (873 seeds per m2) versus the open steppe (109 seeds per m2). To investigate the dynamics of exotic species establishment we planted two exotic species, downy brome (Bromus tectorum) and Dalmation toadflax (Linaria dalmatica), into the open steppe. A matrix of 5 treatments was applied and after one field season Bromus tectorum germinated and established in many plots. The nitrogen and nitrogen plus water treatments were the most successful in promoting the growth of Bromus. Linaria dalmatica did not establish in any of the research plots. The open steppe has few exotic species and we found that few exotic seeds exist in the seed bank. Furthermore, our work indicates that even if exotic species seeds were numerous, they may have difficulty germinating and establishing in the native communities.
Open Access
Ecosystem carbon & nitrogen cycling across a precipitation gradient of the central Great Plains
(Colorado State University. Libraries, 2005) Knapp, A. K., author; Lauenroth, W. K., author; Burke, I. C., author; McCulley, R. L., author; SGS-LTER, Colorado State University, publisher
Regional analyses have shown that ecosystem pools of carbon (C) and nitrogen (N) increase as precipitation increases from the semi-arid shortgrass steppe to the tallgrass prairie of the Central Great Plains. Models based on our functional understanding of biogeochemical processes predict that ecosystem C and N fluxes also increase across this community gradient; however, few field flux data exist to evaluate these predictions. We measured decomposition rates, soil respiration, and in situ net nitrogen mineralization at five sites across a precipitation gradient in the Great Plains region. Soil respiration (SResp) and the decomposition constant, k, for common substrate litter bags were significantly higher in the sub-humid mixed and tallgrass prairie (growing season average mid-day SResp = 7.20 μmol CO2 m-2 sec-1, k = 0.66 yr-1) than the semi-arid shortgrass steppe (SResp = 4.55 μmol CO2 m-2 sec-1, k = 0.32 yr-1). In contrast, in situ net nitrogen mineralization was not significantly different across sites. The C flux data concur with predictions from current biogeochemical models; however, the in situ net nitrogen mineralization results do not. We hypothesize that this discrepancy results from the difficulties associated with measuring in situ net nitrogen mineralization in soils with vastly different immobilization potentials.
Open 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.
Open Access
HistoryDB
(Colorado State University. Libraries, 2009) Melendez-Colom, Eda, author; Kaplan, Nicole, author; Baker, Karen, author; Wiley, Sean, author; Petersen, Robert I., author; SGS-LTER, Colorado State University, publisher
Organizational history requires a facility to manage, archive and present event details as well as narratives that provide perspective to the events. While events form a historical thread, storied narratives weave these threads together into a retrospective. The LTER Information Management Committee has recognized that working collaboratively to understand their history is a tool for exploring how they function within the LTER organizational structure. Such a tool provides valuable input to the development of governance procedures for community-level efforts.
Open 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.
Open 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.
Open 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.
Open Access
LTER IMC community of practice: a learning environment
(Colorado State University. Libraries, 2008) Millerand, Florence, author; O'Brien, Margaret, author; Gil, Inigo San, author; Kaplan, Nicole, author; Baker, Karen, author; SGS-LTER, Colorado State University, publisher
Communities of practice are groups of people who share a concern or a passion for something they do and learn how to do it better as they interact regularly. A community of practice is not merely a group of people having the same job or a network of connections between people.
Open 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.
Open 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.
Open Access
Phosphorus fractionation chemistry across the Great Plains
(Colorado State University. Libraries, 2005) Kelly, E. F., author; Blecker, S. W., author; Ippolito, J. A., author; Freeman, C. L., author; SGS-LTER, Colorado State University, publisher
Phosphorus is one of the three important plant nutrients found in soils and has been used with great success as an index for soil and ecosystem development (Aguilar et al., 1988; Honeycutt et al., 1990; Vitousek et al., 2004). In general, phosphorus is has minimal solubility in soil because it participates in a number of secondary reactions after release from primary minerals as a result of weathering. Studies of the biogeochemical cycling of P in humid ecosystems has led to important insights about soil and ecosystem development. Arid and semi-arid ecosystems have largely been ignored under the assumption that chemical transformations are minimal. We conducted research on the biogeochemistry of P along a bioclimatic gradient in grassland ecosystems of the Great Plains. The overall goal of our research is to use a systematic approach to characterize and further quantify the P transformations in biogeographically diverse grassland ecosystems. Identifying P quantities originally contained in central Great Plains soil will allow us to assess 1) the relative importance of P in the biogeochemical behavior of grassland soils, 2) help us quantify the degree of chemical weathering in semi-arid-humid grassland ecosystems, and 3) elucidate cultural use and potential productivity of these ecosystems prior to use of commercial fertilizers. We sampled soils along a bioclimatic gradient that represent three grassland ecosystems, namely, the shortgrass steppe, the mixed-grass prairie, and the tallgrass prairie in eastern Kansas. The soils were collected from sites studied within the Long-Term Ecological Research Program in areas that had not been used for agricultural practices other than grazing. We conducted a sequential extraction procedure to identify the following P fractions: soluble, Al-bound, Fe-bound, occluded, and Ca-bound. Our results suggest that soluble P is generally below detection limits at these sites, illustrating the high turnover rate of available P in these undisturbed systems. The Al-bound fraction was variable across all sites. The Fe-bound P contributed to the total P fraction only from the mixed grass and tall grass prairies. The occluded P fraction was greatest in the shortgrass steppe, decreased dramatically as mean annual and primary production increase from west to east.
Open 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.