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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Mating and interspecific behavior of greater prairie chicken

Anderson, Raymond Kenneth, January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
132

Resource selection by black-footed ferrets in relation to the spatial distribution of prairie dogs

Jachowski, David Scott. January 2007 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 29, 2007) Includes bibliographical references.
133

COMPETATIVE EVQUIVALENCY OF CULTIVAR AND NON-CULTIVAR DOMINANT GRASSES IN AN EXPERIMENTAL RESTORATION

Reed, Lewis 01 May 2010 (has links)
AN ABSTRACT OF THE THESIS OF LEWIS KENNEDY REED, for the Master of Science degree in PLANT BIOLOGY presented on October 30, 2009, at Southern Illinois University Carbondale TITLE: COMPETATIVE EVQUIVALENCY OF CULTIVAR AND NON-CULTIVAR DOMINANT GRASSES IN AN EXPERIMENTAL RETORATION MAJOR PROFESSORS: Dr. Sara G. Baer and Dr. David J. Gibson Multiple population sources of species for use in prairie restoration exist, including cultivars and non-cultivars of dominant native grasses. However, little is known about the competitive equivalency of different population sources of dominant C4 grasses and whether intraspecific variation in their competitive effect on the community scales to affect ecosystem assembly. In 2006, an experimental restoration was established in a former agricultural field using cultivars and non-cultivars of the dominant grasses (Andropogon gerardii, Sorghastrum nutans, and Schizachyrium scoparium) and two different species pools of non-dominant species containing equal richness and distribution of species among functional groups. I evaluated inter - and intra-specific variation in the competitive equivalency of A. gerardii, S. nutans, and S. scoparium in terms of community response to their individual and complete (all three species) removal. Removals were maintained for two growing seasons, though little maintenance was needed after the initial treatment. The competitive effect of each grass species and population source was determined by calculating a response ratio for percent cover and above ground primary productivity between removal and control plots for each dominant grass individually, forbs, non-dominant grasses, and legumes which were each analyzed using a mixed model procedure for a split-split-plot randomized block design. Effects of removals on overall community composition were assessed using non-metric multi-dimensional scaling (NMDS) and analysis of similarity (ANOSIM). In addition I monitored changes in photosynthetically active radiation (PAR) at the soil surface and inorganic soil nitrogen. Based on the 2008 data (after two years of maintaining removals), several important differences were detected between the focal species and in some cases the two sources of the same species in terms of their effects on neighbors, inorganic soil nitrogen, and PAR. Many of these differences depended on which species pool the comparison took place in. A 3-way interaction was detected between species pool, source, and removal treatment in the volunteer forb group (F3, 60 =3.28, p = 0.0268). Volunteer forbs showed a positive response to removal of cultivars of the dominant grass functional group in one species pool but not the other. A three-way interaction was detected between species pool, source, and removal treatment in terms of Bray-Curtis similarity (F3, 60 = 2.91, p = 0.0417). Within one of the species pools, similarity values of communities were higher between removals and controls in cultivar plots than in non-cultivar plots where A. gerardii was removed. While NMDS ordination showed separation of some plots by dominant grass source, within group variation was higher than among group variation and ANOSIM deemed this separation insignificant. Planted forb ANPP exhibited a significantly negative response to removal of S. nutans that was not observed in the other removal treatments (F3,41.1 = 3.09, p = 0.038) suggesting facilitation by the dominant grass on planted forbs. The aboveground net primary productivity (ANPP) of the subordinate community (i.e. all species except the dominant grasses) exhibited a 3-way interaction among species pool, dominant grass source, and species removed (F3,61 = 2.76, p=0.0499). This interaction resulted from a stronger negative response of subordinate community ANPP to cultivars of the dominant grass functional group removal than non-cultivars of this group that only occurred in one of the species pools. There was a significant main effect of species removed on %PAR at ground level (F3, 60 = 4.84, p = 0.0044). All removal treatments allowed higher penetration of PAR to ground level, with S. nutans and all dominant grass removal having the strongest effect. Inorganic N availability was lower in response to removal of A. gerardii cultivars compared to the removal of non-cultivars of this species in one species pool but not the other. Removal of cultivar S. scoparium lead to a positive response in total inorganic nitrogen while removal of non-cultivars of this species lead to a negative response in total inorganic nitrogen in this same species pool (F3, 51 = 3.61, p = 0.018). Results demonstrate that inter- and intra-specific variation among these dominant species affect some aspects of community structure and ecosystem properties, but these effects are not consistent among dominant species and among subordinate species pools. These complex interactions may have important implications for restoration and land management.
134

THE ROLE OF SOIL HETEROGENEITY IN THE RECRUITMENT OF NEW SPECIES AND INTERACTIONS WITH GRASSHOPPERS (ACRIDIDAE) AND KATYDIDS (TETTIGONIIDAE) IN RESTORED PRAIRIE

Adams, Tianjiao 01 May 2017 (has links)
Tallgrass prairie in North America has been severely degraded over the past century due to anthropogenic changes and is a subject of many restoration projects. Using these restoration projects, it is possible to examine potential drivers that influence community assembly. The environmental heterogeneity hypothesis provides a basis for enhanced diversity as function of resource partitioning and coexistence of potentially competing species. In essence, an area with higher levels of resource heterogeneity would be able to support a higher number of potentially competing species in contrast to an area with lower levels of resource heterogeneity (e.g. agricultural fields). The tallgrass prairie is naturally heterogeneous in abiotic resources such as soil depth and soil nitrogen, native prairie species both drive and exploit this heterogeneity and assemble a highly biodiverse community. Chapter 2 attempted to elucidate the effect of soil resource heterogeneity on plant community assembly, niche availability, and dimensionality. Chapter 3 attempted to examine the indirect influence of soil resources on aboveground Orthoptera herbivores. Both studies were conducted in a 16-year tallgrass prairie restoration experiment over a two-year period. There were no differences in plant community composition on a whole plot level. However, on a subplot level, shallow soil generally resulted in higher species richness and diversity. In contrast to previous studies, I found nitrogen addition increased forb richness and nitrogen reduction reduced forb diversity. As expected, the dominant grass Andropogon gerardii was positively influenced by high nitrogen regardless of soil depth. The multivariate analysis indicated the new species added to the experiment had unique trait spaces. Further analysis indicated niche availability and dimensionality were highest in treatments with nitrogen addition. This study suggests though fine scale spatial heterogeneity influences plant community composition, coarse scale spatial heterogeneity does not. This study also suggests that soil nitrogen may be a poor indicator of plant species diversity in the tallgrass prairie community. Orthoptera richness and biomass were higher in maximum heterogeneity treatments relative to control. The influence of high resource heterogeneity was highest on the richness of mixed-feeder grasshoppers and katydids. This effect, however, was inconsistent between years. Grass-feeder biomass was higher in the maximum heterogeneity treatment than control both years. This was attributed to nitrogen addition resulting in patches of higher quality forage in the maximum heterogeneity plots. Orthopterans are also influenced by the structural complexity of the plant community mediated by varying levels of soil resources. The maximum heterogeneity treatment contained higher variation in the cover and ANPP of a dominant grass, Andropogon gerardii. The positive relationship between plant richness and Orthoptera diversity suggests that maintaining plant richness in restored areas is important for maintaining diversity of higher trophic levels. The negative relationship between light interceptions and Orthoptera abundance suggests the dense vegetation from dominant tallgrass species may impede recruitment of some species. These results suggest suppression of dominant grasses can positively influence the plant community composition and Orthoptera herbivores. Understanding how soil resources influence plant community composition and higher trophic levels can aid our understanding of the community assembly process. Plant species benefited from higher variation in soil resources, particularly soil depth and soil nitrogen, while insect herbivores that depended on these plant species were also indirectly benefited. This study suggests soil heterogeneity is important for the assemblage of species on a multi-trophic level and this knowledge can assist land managers in restoration projects to achieve desired goals.
135

Restoration of tallgrass prairie degraded by the noxious weed sericea lespedeza

Gatson, Garth Arnold January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / K C Olson / The largest intact remnant of the tallgrass prairie, the Flint Hills ecoregion, is currently under threat from the invasive weed sericea lespedeza (Lespedeza cuneata [Dumont] G. Don; SL). The objectives of this research were to evaluate the efficacy of late-season prescribed burning and fall herbicide application, alone and in concert, for comprehensive control of sericea lespedeza and to assess their broader treatment impacts on native plant communities. A 31-ha native tallgrass pasture with a light to moderate infestation of SL was divided into 16 subunits for this experiment. Each subunit was randomly assigned to 1 of 4 treatments: negative control, spray-only, burn-only, or burn-plus-spray. A prescribed burn was conducted on burn-only and burn-plus-spray subunits in early September 2016. Following the re-emergence of SL, spray-only and burn-plus-spray subunits received a broadcast application of metsulfuron methyl (Escort XP, DuPont, Wilmington, DE) at a rate of 70.1 g ˖ ha⁻¹ in late September. Frequency and vigor of SL, total forage biomass, soil cover, and plant species composition were measured along permanent 100-m transects in each subunit prior to treatment application and again 12 mo later, in 2017 (i.e., 1 YAT). In 30 x 30-cm plots at 1-m intervals along each transect, the presence or absence of SL was noted. Where SL was present, crown maturity and maximum stem length of the SL plant nearest to the transect were recorded. Presence of multiple stems in plots was also recorded. Prior to treatment application, SL comprised 1 ± 2.0% of total basal cover and was not different between treatments (P = 0.38). One YAT, SL was more abundant (P ≤ 0.02) in negative control subunits than in spray-only, burn-only, or burn-plus-spray subunits, which were not different (P ≥ 0.95) from one another. Aerial frequency of SL, abundance of mature SL crowns, and incidence of plots with multiple SL stems were greatest (P ≤ 0.03) for negative controls, although not different (P ≥ 0.50) between the other 3 treatments. The change in forage biomass production 1 YAT did not differ (P = 0.16) between treatments. A tendency (P = 0.06) for a shift from litter cover to bare soil was noted when the spray-only, burn-only, and burn-plus-spray treatments were compared to the negative control. Graminoid basal cover was greater (P < 0.01) in the spray-only and burn-plus-spray treatments than in the negative-control and burn-only treatments 1 YAT. Conversely, forb basal cover was less (P = 0.01) in spray-only and burn-plus-spray treatments than in negative-control and burn-only treatments. The evenness component of diversity decreased in the burn-plus-spray treatment relative to the negative control (P ≤ 0.01). These data indicate that each of these strategies were effective in reducing SL populations. Although late-summer prescribed burning produced no detected negative responses within the native plant community, fall herbicide application, alone or in conjunction with prescribed burning, resulted in collateral damage to forb populations. A late-summer prescribed burn alone is recommended for low-cost comprehensive control of a light to moderate sericea lespedeza infestation.
136

River ice conditions in the Nelson drainage system

MacKay, Donald Kenning January 1962 (has links)
Hydrological and meteorological observations related to ice conditions on rivers in the Nelson drainage system are compared statistically to determine the measure of agreement between them. The results show a high degree of positive correlation. The areal variability of ice formation, ice disintegration, mean length of the ice-free season, and the standard deviation of first-ice and last-ice are plotted on maps. The data has been based upon ten-year mean dates and also the entire 1921 to 1950 period. The progress of ice formation and disintegration is examined statistically both latitudinally and also along the major tributaries of the Nelson River. Results indicate that first appearance of ice affecting discharge generally follows the expected north to south pattern; no systematic progression along tributaries in either an upstream or a downstream direction is apparent. On each major tributary tested, ice disintegration progresses downstream. Latitudinal progress follows a south to north pattern with the exception of the southeasterly-flowing portion of the Assiniboine River. Trends and fluctuations in ice formation and disintegration are studied by five-point filtered series. Break-up (last-ice) occurred earliest in the mid-1940’s whereas freeze-up showed no definite trend. Filtered series of ice formation dates appear to exhibit greater co-variability than those of ice disintegration dates. The variability of break-up on headwater streams could be a factor in limiting the covariability between last-ice records due to the dependency of break-up at downstream sites on upstream conditions. Trends in the length of ice-free (open) season for 1921 to 1950 are examined using cumulative percentual deviations from the mean. At most locations in the Nelson basin, the length of the ice-free season was shorter than average from 1921 to the early l930’s and longer than average in the last half of the record. Cumulative percentual deviations from the mean ice-free season are compared to those from the mean annual air temperature. Mean annual air temperatures and lengths of ice-free season do not appear to be significantly correlated in the Nelson basin. The study of factors affecting the formation and disintegration of river ice in the Nelson basin is limited primarily to a discussion of the relationships among air temperatures, ice conditions, and river discharge. The extent and variability of freezing and melting degree days before ice formation and disintegration are examined for the period 1921 to 1950. Local air temperatures are extremely variable before first-ice and last-ice dates. Ice may be reported when temperatures are above the freezing point; break-up may occur when temperatures are below the freezing point. Two possible explanations for first-ice being observed under thawing conditions are: (a) ice formed under freezing conditions upstream moving downstream: and (b) the pooling of cold air in entrenched valleys resulting in ice formation. The occurrence of last-ice under freezing conditions may be caused by freeze-thaw cycles weakening the structure of the ice cover combined with increases in discharge raising and cracking it. Mean discharge rates (1921 to 1950) prior to ice disintegration are computed and graphed for seven locations in the Nelson basin. Mean rates increase three to five times in the ten-day period preceding break-up. Increases in discharge appear to be one of the prime factors contributing to ice disintegration. / Arts, Faculty of / Geography, Department of / Graduate
137

Common misperceptions of the events relating to the rise of the protest movements on the prairies

Sanguinetti, Sonja Patricia January 1969 (has links)
This paper presents a model based on a synthesis of the four major themes in the standard literature on the rise of the protest movements on the prairies. The themes are a homogeneous population, a quasi-colonial economy, a non-partisan political system and the depression. They are given as explanations for the coming to power of the Progressive, Social Credit, and C.C.F. parties by the authors of this literature such as Morton, Sharp, Lipset, and Macpherson. An examination of the data relating to voter behaviour and population composition shows this model to be over-simplified. The imperfections of it are further highlighted by the historical data which indicate the different patterns of development of the western provinces. The political situation which arose in Canada after the 1917 election seems to give a much better indication of how the protest parties were able to achieve success on the prairies. In other words, both the total Canadian context and the individual provincial histories must be considered if one desires to understand the protest movement on the prairies. / Arts, Faculty of / Political Science, Department of / Graduate
138

Wetland retention on the prairies through private landowner stewardship

Hursin, Tamara Julie Irene 05 1900 (has links)
Loss and degradation of wetlands across Canada's prairie pothole region in Canada is severe and accelerating as on-going intensification and expansion of the agricultural land base continues to exert pressure on the remaining wetland resource. Traditionally wetlands have been regarded as unexploited wastelands to be converted to more productive agricultural uses. Although wetlands are now recognized as providing vital functions of a hydrological, ecological and social nature which have economic and social value as well as intrinsic value, difficulties in quantifying these benefits, coupled with readily calculated and realized benefits from agricultural production, result in continuing wetland losses. As well, because wetland benefits accrue to the general public rather than the private land holders who dominate the pothole region, individual owners cannot capture payment for these benefits and thus favor agricultural production over wetland retention. The primary objective of the thesis is to evaluate nonregulatory approaches to encouraging private landowner stewardship on the prairies with respect to wetland retention. From the literature, it is established that a nonregulatory approach to preserving wetlands on private lands is preferable to police power regulation from both a landowner and general public perspective. Several benefits associated with using nonregulatory tools to promote changes in landowner behavior are identified and developed into an analytical framework. Using this framework, six market and moral suasion nonregulatory tools commonly used to encourage landowners to retain wetlands are assessed for their apparent advantages and disadvantages in supporting the primary concerns of landowners faced with a decision whether to enter into a stewardship program. From this assessment, conclusions regarding probable owner acceptability of the mechanisms are drawn, acceptability being a measure for how successful the nonregulatory tools will be in promoting private stewardship of wetlands. The expected landowner appeal of the mechanisms is tested by evaluating their actual owner appeal as implemented in three on-going Canadian stewardship programs. Actual appeal is found to be fairly consistent with results from the literature analysis and conclusions from these results indicate that the mechanisms do vary in their effectiveness to encourage landowners to retain wetlands and thus vary in their ability to secure wetland acreage for protection. Data limitations are encountered in the case studies due to the infancy of stewardship programs in Canada and thus it is concluded that it will take time to demonstrate the effectiveness of nonregulatory mechanisms in promoting private landowner stewardship of wetlands. The evaluation of nonregulatory tools allows a number of recommendations to be drawn with regard to improving stewardship programs in order to effectively encourage landowner participation, the type of data base that needs to be established in order to effectively monitor the success of nonregulatory mechanisms, and opportunities for further investigation in this area of study. / Graduate and Postdoctoral Studies / Graduate
139

Prairie Dog (Cynomys Ludovicianus) Contributions to Soil Change on Grazed Mixed-Grass Prairie

Barth, Cory John January 2012 (has links)
Vegetation and soils were evaluated on a black-tailed prairie dog (Cynomys ludovicianus) colony and adjacent non-disturbed mixed-grass prairie in central South Dakota. The study’s objectives were 1) determine differences in plant species diversity and richness, and selected soil quality parameters between prairie dog colonies and adjacent non-disturbed sites, and 2) evaluate impacts of prairie dogs on water infiltration rates. Three soil series were evaluated representing three ecological sites (Opal, Cabba, and Wayden). Plant species richness was higher on the Control on Opal soils, while being lower on the Control on Cabba soils. Lower soil pH and higher nitrate concentrations were found on the prairie dog town for Opal and Cabba soils near the soil surface, close to the prairie dog mounds. These findings show prairie dog impacts on soil parameters can vary across different soil types, which can affect the diversity and richness of vegetative communities within prairie dog colonies.
140

Food Interactions Between Utah Prairie Dogs and Cattle

Crocker-Bedford, Dennis 01 May 1976 (has links)
This study examined the food interactions between Utah prairie dogs (Cynomys parvidens, Allen) and cattle (Bos taurus), During 1974 and 1975, three prairie dog colonies near Panguitch, Utah, were studied intensely: "Oldfield" was chosen to represent colonies near fields of alfalfa (Medicago sativa); "Lowercrested" was chosen to represent colonies below 2,200 meters above sea level (a. s. 1.) which were not near alfalfa, and "Uppercrested" was chosen to represent colonies above 2,200 meters a.s.l. which have been planted with crested wheatgrass. Visual observations were made of Utah prairie dogs to determine their diets. Livetrapping of prairie dogs provided data for estimates of population sizes and animal weights, which were used to calculate forage requirements. Cattle diets and forage intake per individual were derived from the literature. Much more forage was available to prairie dogs than to cattle. About 80 percent of the forb phytomass ingested by prairie dogs at Uppercrested never would have become available to cattle. Prairie dogs foraged more selectively than cattle are capable of doing. Neither animal showed a general dietary preference toward either grasses or forbs: each plant life form contained bath preferred and avoided species. Bath animals had a low preference for shrubs. Oldfield's area tripled between 1971 and 1974, but Uppercrested did not expand. Between 1 June, 1974, and 1 June, 1975, Oldfield's population increased from about 42 to 70 adult prairie dogs, and the colony's area increased proportionately; however, Uppercrested's population appeared to decline from approximately 22 to 19 adults. The dissimilar expansion rates, at least between 1974 and 1975, probably were due to differences in behavior, forage availability, nutrition, and predation. Oldfield's prairie dogs gained weight much faster than did Uppercrested's animals. Thus, the average number of active Utah prairie dogs ingesting as much forage as a cow and calf from March through October (prairie dogs fed little during other months) was 410 at Oldfield, compared to 500 at Uppercrested. Numbers concerning total utilization may be even higher: prairie dogs waste little vegetation, but cattle probably trample much. On the other hand, prairie dogs clip closer to the ground and earlier in the growth season than do cattle; consequently, prairie dogs may cause a greater reduction in primary production for the same amount of forage intake. Population densities of prairie dogs in late June, one month after the young first emerged, were 35/ha at Oldfield, 16/ha at Lowercrested, and less than 2.3/ha at Uppercrested. Prairie dogs used over 70 percent of the primary production of perennial herbage at Oldfield and about 10 percent of it at Lowercrested. Uppercrested's prairie dogs used approximately 3 percent of the primary production of crested wheatgrass, a preferred forage. Within any one year, cattle probably rarely reduce population s of Utah prairie dogs, and possibly may increase populations in colonies with high primary production. Prairie dogs apparently have reduced the primary production of perennial herbage at bath Oldfield and Lowercrested. Vegetational canopy coverage was greater on mounds than off mounds in the low use portion of Uppercrested. Heavy grazing by livestock in the past probably has eliminated much Utah prairie dog habitat: swales have been destroyed and early spring forage has been reduced.

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