1,720,961 research outputs found
Does sericea lespedeza create a soil legacy that impacts grassland recovery?
No full textPresented to the 11th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Heskett Center, Wichita State University, April 24, 2015.Research completed at Department of Biological Sciences, Fairmount College of Liberal Arts and Sciences & Department of Ecology and Evolutionary Biology and Kansas Biological Survey, University of KansasSericea lespedeza (Lespedeza cuneata) is a non-native, invasive legume that is a growing threat to Kansas prairies. Current evidence suggests that sericea may alter soil conditions, potentially stimulating its own growth and negatively impacting native species in prairie communities. If correct, sericea may create a soil legacy effect even if control measures have effectively removed sericea, thereby slowing or preventing the recovery of native species.
To test this idea, sericea was sown into 300 experimental plots at a wide range of densities (0 to 10,000 seeds m-2) in a prairie plant community located in Northeast Kansas. A fertilization and simulated disturbance regime was applied during the first two years of experimentation, along with appropriate ambient controls, during a previous experiment at the same site to examine the establishment of sericea under these regimes. After a three-year establishment period, the community was burned in the fall and sprayed with herbicide the following year to eliminate sericea. Following sericea control measures, thirteen native species were sown into all plots. The stem density of the sown native species was recorded in an annual census over the next four years. If sericea was found in any plots during this period, the stem density of sericea was recorded and individuals were manually removed. In addition, the percent cover of all species present in each plot was recorded in the final annual census.
A significant effect of historical disturbance (Pseudo-F2, 243 = 2.8, P 0.9), but had a negative effect on native species cover within the simulated grazing (F1, 107 = 5.3, P = 0.02) and fertilization treatments (F1, 134 = 4.3, P = 0.04), however the variation explained by the model was quite low (R2 < 0.05 for both comparisons). Likewise, multivariate analysis of all species also indicated weak effects of historical sericea density. Taken together, these results suggest that sericea does not appear to create a soil legacy if controlled within the first three years of sericea establishment.Graduate School, Academic Affairs, University Librarie
Recovery of a prairie plant community following sericea lespedeza (Lespedeza Cuneata) removal: Testing for a soil legacy effect
No full textSericea lespedeza (Lespedeza cuneata) is an invasive legume threatening plant
communities in the southeastern and southcentral United States. In addition to reducing native
species abundance, current evidence suggests that L. cuneata invasion may alter soil conditions
in host communities. If correct, L. cuneata may create a soil legacy effect that impacts
community recovery, even if control measures have effectively removed L. cuneata. I examined
the recovery of a prairie plant community in Jefferson county, Kansas to determine if the
historical presence of L. cuneata affected 1) the relative abundance of all species and 2) the
colonization of native species in the community four years following L. cuneata removal. To
address this, L. cuneata seeds were sown into 300 plots at a wide range of densities (0 to 10,000
seeds m-2
) under different combinations of simulated disturbance and soil fertilization. After a
three-year establishment period, the percent cover and stem density of L. cuneata was recorded,
and the community was burned and sprayed with herbicide to eliminate L. cuneata. Fertilization
and disturbance treatments were discontinued, and thirteen native forb species were sown into all
plots. The stem density of all sown species was recorded annually over a four-year recovery
period, and the percent cover of all species present was recorded in the fourth year of recovery.
Analysis of community data in response to the historical presence of L. cuneata did not
indicate the presence of a soil legacy effect. Although the relationship between community
species cover and the historical cover of L. cuneata was significant in some cases, the variation
explained by these comparisons was quite low. Similarly, the colonization of sown native species
in the community was unrelated to the historical cover of L. cuneata. These results indicate that
L. cuneata does not create a soil legacy effect if effectively controlled within the first three years
of invasion, regardless of initial density.Thesis (M.S.)--Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Biological Science
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Effects of precipitation, grazing and initial planting practice on CRP plant diversity across Kansas
No full textPresented to the 14th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Rhatigan Student Center, Wichita State University, April 27, 2018.Research completed in the Department of Biological Sciences, Fairmount College of Liberal Arts and Sciences and Department of Biological Sciences, Emporia State UniversityThe Conservation Reserve Program (CRP) is a federally funded program that has converted marginal cropland to native plant communities over the past 30 years with the goal of preventing erosion, improving water quality, and reducing loss of wildlife habitat and biodiversity. Nationwide, 23.5 million acres are currently enrolled in CRP, yet few studies have examined plant communities on CRP lands at a large scale. As part of a larger three-year study, we collected vegetation data from 108 CRP sites across the precipitation gradient in Kansas to determine the effects of planting practices (CP2 and CP25) and periodic grazing on plant
communities. In 2017, plant species richness increased linearly with the precipitation gradient from an average of 5 species per m2 in the west to 10 species per m2 in eastern Kansas. Across sites, 88 plant species were identified in the western region, 125 in the central, and 143 in the eastern region. Collectively, 237 species were found across the 108 sites, representing over 11% of all plant species that occur in Kansas. Neither grazing nor planting practice had a detectable
effect on plant species richness or evenness in the first year of the study.Graduate School, Academic Affairs, University Librarie
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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