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Rangeland dynamics: investigating vegetation composition and structure of urban and exurban prairie dog habitat  [PDF]
Rebecca Hopson,Paul Meiman,Graeme Shannon
PeerJ , 2015, DOI: 10.7717/peerj.736
Abstract: Rapid human population growth and habitat modification in the western United States has led to the formation of urban and exurban rangelands. Many of these rangelands are also home to populations of black-tailed prairie dogs (Cynomys ludovicianus). Our study aimed to compare the vegetation composition of an urban and exurban rangeland, and explore the role that prairie dogs play in these systems. The percent absolute canopy cover of graminoids (grasses and grass-likes), forbs, shrubs, litter, and bare ground were estimated at sampling areas located on and off prairie dog colonies at an urban and an exurban site. Herbaceous forage quality and quantity were determined on plant material collected from exclosure cages located on the colony during the entire growing season, while a relative estimate of prairie dog density was calculated using maximum counts. The exurban site had more litter and plant cover and less bare ground than the urban site. Graminoids were the dominant vegetation at the exurban plots. In contrast, mostly introduced forbs were found on the urban prairie dog colony. However, the forage quality and quantity tests demonstrated no difference between the two colonies. The relative prairie dog density was greater at the urban colony, which has the potential to drive greater vegetation utilization and reduced cover. Exurban rangeland showed lower levels of impact and retained all of the plant functional groups both on- and off-colony. These results suggest that activities of prairie dogs might further exacerbate the impacts of humans in fragmented urban rangeland habitats. Greater understanding of the drivers of these impacts and the spatial scales at which they occur are likely to prove valuable in the management and conservation of rangelands in and around urban areas.
Monkeypox Disease Transmission in an Experimental Setting: Prairie Dog Animal Model  [PDF]
Christina L. Hutson, Darin S. Carroll, Nadia Gallardo-Romero, Sonja Weiss, Cody Clemmons, Christine M. Hughes, Johanna S. Salzer, Victoria A. Olson, Jason Abel, Kevin L. Karem, Inger K. Damon
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0028295
Abstract: Monkeypox virus (MPXV) is considered the most significant human public health threat in the genus Orthopoxvirus since the eradication of variola virus (the causative agent of smallpox). MPXV is a zoonotic agent endemic to forested areas of Central and Western Africa. In 2003, MPXV caused an outbreak in the United States due to the importation of infected African rodents, and subsequent sequential infection of North American prairie dogs (Cynomys ludovicianus) and humans. In previous studies, the prairie dog MPXV model has successfully shown to be very useful for understanding MPXV since the model emulates key characteristics of human monkeypox disease. In humans, percutaneous exposure to animals has been documented but the primary method of human-to-human MPXV transmission is postulated to be by respiratory route. Only a few animal model studies of MPXV transmission have been reported. Herein, we show that MPXV infected prairie dogs are able to transmit the virus to naive animals through multiple transmission routes. All secondarily exposed animals were infected with MPXV during the course of the study. Notably, animals secondarily exposed appeared to manifest more severe disease; however, the disease course was very similar to those of experimentally challenged animals including inappetence leading to weight loss, development of lesions, production of orthopoxvirus antibodies and shedding of similar levels or in some instances higher levels of MPXV from the oral cavity. Disease was transmitted via exposure to contaminated bedding, co-housing, or respiratory secretions/nasal mucous (we could not definitively say that transmission occurred via respiratory route exclusively). Future use of the model will allow us to evaluate infection control measures, vaccines and antiviral strategies to decrease disease transmission.
Prairie Dog Decline Reduces the Supply of Ecosystem Services and Leads to Desertification of Semiarid Grasslands  [PDF]
Lourdes Martínez-Estévez, Patricia Balvanera, Jesús Pacheco, Gerardo Ceballos
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0075229
Abstract: Anthropogenic impacts on North American grasslands, a highly endangered ecosystem, have led to declines of prairie dogs, a keystone species, over 98% of their historical range. While impacts of this loss on maintenance of grassland biodiversity have been widely documented, much less is known about the consequences on the supply of ecosystem services. Here we assessed the effect of prairie dogs in the supply of five ecosystem services by comparing grasslands currently occupied by prairie dogs, grasslands devoid of prairie dogs, and areas that used to be occupied by prairie dogs that are currently dominated by mesquite scrub. Groundwater recharge, regulation of soil erosion, regulation of soil productive potential, soil carbon storage and forage availability were consistently quantitatively or qualitatively higher in prairie dog grasslands relative to grasslands or mesquite scrub. Our findings indicate a severe loss of ecosystem services associated to the absence of prairie dogs. These findings suggest that contrary to a much publicize perception, especially in the US, prairie dogs are fundamental in maintaining grasslands and their decline have strong negative impacts in human well – being through the loss of ecosystem services.
Constance Lucile Murray
Oklahoma Native Plant Record , 2005,
Abstract: The effect of pimple mound microrelief on the vegetation of a tall grass prairie was considered. Taxonomic analysis of the vegetation affirmed the observation that mound and intermounds support communities with differing species composition. The difference in the percent cover by living vegetation on mounds and intermounds was determined not to be statistically significant. The physical composition of the soil in the two regions was found to be similar. Two factors are suggested as influencing the differences in mound and intermound vegetation: that mound soils can provide more available water to plants than can intermound soils, and that mounds, but not intermounds, contain the burrows of small mammals and are modified by their presence.
Transmissibility of the Monkeypox Virus Clades via Respiratory Transmission: Investigation Using the Prairie Dog-Monkeypox Virus Challenge System  [PDF]
Christina L. Hutson, Nadia Gallardo-Romero, Darin S. Carroll, Cody Clemmons, Johanna S. Salzer, Tamas Nagy, Christine M. Hughes, Victoria A. Olson, Kevin L. Karem, Inger K. Damon
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0055488
Abstract: Monkeypox virus (MPXV) is endemic within Africa where it sporadically is reported to cause outbreaks of human disease. In 2003, an outbreak of human MPXV occurred in the US after the importation of infected African rodents. Since the eradication of smallpox (caused by an orthopoxvirus (OPXV) related to MPXV) and cessation of routine smallpox vaccination (with the live OPXV vaccinia), there is an increasing population of people susceptible to OPXV diseases. Previous studies have shown that the prairie dog MPXV model is a functional animal model for the study of systemic human OPXV illness. Studies with this model have demonstrated that infected animals are able to transmit the virus to naive animals through multiple routes of exposure causing subsequent infection, but were not able to prove that infected animals could transmit the virus exclusively via the respiratory route. Herein we used the model system to evaluate the hypothesis that the Congo Basin clade of MPXV is more easily transmitted, via respiratory route, than the West African clade. Using a small number of test animals, we show that transmission of viruses from each of the MPXV clade was minimal via respiratory transmission. However, transmissibility of the Congo Basin clade was slightly greater than West African MXPV clade (16.7% and 0% respectively). Based on these findings, respiratory transmission appears to be less efficient than those of previous studies assessing contact as a mechanism of transmission within the prairie dog MPXV animal model.
Vegetation Cover Analysis of Hazardous Waste Sites in Utah and Arizona Using Hyperspectral Remote Sensing  [PDF]
Jungho Im,John R. Jensen,Ryan R. Jensen,John Gladden,Jody Waugh,Mike Serrato
Remote Sensing , 2012, DOI: 10.3390/rs4020327
Abstract: This study investigated the usability of hyperspectral remote sensing for characterizing vegetation at hazardous waste sites. The specific objectives of this study were to: (1) estimate leaf-area-index (LAI) of the vegetation using three different methods (i.e., vegetation indices, red-edge positioning (REP), and machine learning regression trees), and (2) map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF)-derived metrics and vegetation indices. HyMap airborne data (126 bands at 2.3 × 2.3 m spatial resolution), collected over the U.S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona, were used. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. Regression trees resulted in the best calibration performance of LAI estimation (R2 > 0.80. The use of REPs failed to accurately predict LAI (R2 < 0.2). The use of the MTMF-derived metrics (matched filter scores and infeasibility) and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI) and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches ( < 1 m) found on the sites.
Evaluating Post-Fire Vegetation Recovery in North American Mixed Prairie Using Remote Sensing Approaches  [PDF]
Meng Li, Xulin Guo
Open Journal of Ecology (OJE) , 2018, DOI: 10.4236/oje.2018.812038
Abstract: Research on the effects of fire on grassland ecosystems yields among the most controversial research results. This is caused by the global distribution of grasslands under different environmental conditions in addition to complex fire characteristics (time, severity, frequency, history etc.). Challenges and discrepancies arise from various temporal and spatial scales, as well as methods used. Moreover, the function of fire can be different from one grassland to another. In the large body of grassland fire literature, the Canadian northern mixed prairie is understudied, especially regarding the vegetation’s post-fire recovery. The wildfire in April 2013 provided an opportunity to study how the grassland responded to the burning, and particularly how remote sensing can provide potential solutions to grassland fire studies in this region. This research investigated the vegetation’s post-fire recovery using six years’ field survey data. Results indicate a quick overall recovery of the grassland, but with different vegetation forms recovering at various post-fire growing seasons. Green grass was the most resilient component that fully recovered one year post-fire, followed by forbs at two years post-fire, with shrubs and the soil organic crust taking longer than four years to recover. The ecosystem recovered to the unburned state roughly after four years. This conclusion agrees with the shortest fire interval of some research, probably because of the heavy fuel loading before the wildfire, due to Grasslands National Park’s long-term conservation practice. Both hyperspectral data and historical Landsat images were investigated to demonstrate their effective assessment of the post-fire grassland vegetation recovery trajectory.
Detecting Climate Effects on Vegetation in Northern Mixed Prairie Using NOAA AVHRR 1-km Time-Series NDVI Data  [PDF]
Zhaoqin Li,Xulin Guo
Remote Sensing , 2012, DOI: 10.3390/rs4010120
Abstract: Grasslands hold varied grazing capacity, provide multiple habitats for diverse wildlife, and are a key component of carbon stock. Research has indicated that grasslands are experiencing effects related to recent climate trends. Understanding how grasslands respond to climate variation thus is essential. However, it is difficult to separate the effects of climate variation from grazing. This study aims to document vegetation condition under climate variation in Grasslands National Park (GNP) of Canada, a grassland ecosystem without grazing for over 20 years, using Normalized Difference Vegetation Index (NDVI) data to establish vegetation baselines. The main findings are (1) precipitation has more effects than temperature on vegetation; (2) the growing season of vegetation had an expanding trend indicated by earlier green-up and later senescence; (3) phenologically-tuned annual NDVI had an increasing trend from 1985 to 2007; and (4) the baselines of annual NDVI range from 0.13 to 0.32, and only the NDVI in 1999 is beyond the upper bound of the baseline. Our results indicate that vegetation phenology and condition have slightly changed in GNP since 1985, although vegetation condition in most years was still within the baselines.
Historical accounts of the transformation of a prairie town
Todd D. Fagin,Melissa Scott Brown
Oklahoma Native Plant Record , 2003,
Abstract: Prior to European settlement, the area that would later become Norman, Oklahoma was dominated by prairie vegetation. Woody vegetation was limited to riparian zones and isolated groves presumably protected from the effects of fire. The contemporary landscape of Norman, stands in stark contrast to this “treeless” prairie, and is now characterized by a so-called urban forest. In this paper, we analyze a number of archival sources, ranging from early expedition and traveler accounts to postsettlement photography in order to qualitatively assess the nature of the landscape in and around the present-day city of Norman prior to and immediately following European settlement. We also utilize repeat photography to document the floristic and vegetation changes that have occurred. We found that the pre-European settlement landscape was characterized by rolling prairies heavily influenced by the grazing of black-tailed prairie dogs (Cynomys ludovicianus), bison (Bison bison), and pronghorn antelope (Antilocapra americana). Forbs were limited and herbaceous vegetation was dominated primarily by closely grazed grasses. Woody vegetation was limited primarily to watercourses and ravines, though numerous accounts cite thickets of oaks (Quercusspp.) occurring in the adjacent cross timbers. Today, the vegetation of Norman is characterized by the dominance of woody vegetation. Within Norman’s historical residential areas, commonly occurring species include hackberry (Celtis occidentalis), Shumard’s oak (Q. shumardii), silver maple (Acer saccharinum), and sycamore (Platanus occidentalis).
Investigating the Tallgrass Prairie  [cached]
Marcia V. Burns,Sojin Y. Chi,Nancy B. Hertzog
Early Childhood Research & Practice , 2008,
Abstract: This article describes an investigation of a tallgrass prairie undertaken by 3- through 7-year-old children in a preschool and a combined kindergarten/first-grade classroom at a Midwestern university. The teaching teams were curious about how these two age groups would explore their questions about the prairie—how their questions would differ by age group, what interested them most, and whether they would come to different levels of understanding. The children's involvement in this investigation is illustrated through photographs, samples of their work, and explanations. The article compares the studies in each classroom, discussing how children addressed similar questions and the effects of collaboration on their social and emotional development.
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