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Early Intervention Access and Use: The Impact on Outcomes
Get PDFThe purpose of this research paper was to investigate the factors that influence a person’s access to and use of early intervention (EI) services. In the literature, there are demonstrated short- and long-term benefits for populations with disorders or delays associated with EI. Speech-language pathologists are one of many professionals that may work with EI clients, and they should be especially interested in ensuring that all individuals receive necessary services. Previous research suggests that race, ethnicity, and socioeconomic status impact access to EI. This study examines possible methods of increasing access to EI for populations that are less likely to receive services
Special Collections 2021-2022 Annual Report
Get PDFThe 2021-2022 annual report from Augustana College\u27s Special Collections
Theater auf der Wieden - History of location, audiences, and mechanics
Get PDFThere are many historical connections between Vienna’s theater scene and the original theater that Mozart’s Die Zauberflöte was performed in. This paper discusses the audiences of the Theater, the location, architecture and mechanics. Although much has changed within theaters since the 18th century, some things still remain the same
Assessment of the Negative Role Garlic Mustard has on Urban Forest Diversity
No full textAlliaria petiolata (garlic mustard), is an invasive biennial herb native to Europe and Asia. Its roots excrete a chemical that inhibits the growth of surrounding plants. When A. petiolata is present, low species diversity results. Once A. petiolata is present, it is almost impossible to eradicate due to how quickly it spreads. Additionally, A. petiolata eliminates native species such as oaks and wildflowers, therefore reducing a site’s richness and evenness. Our research question is how does A. petiolata cover affect native species in the herbaceous understory? Five forest communities were sampled in Northwest Illinois. Sites were separated into four different categories with Lonicera maackii (Amur Honeysuckle) only, A. petiolata only, neither invasive species, and sites where both occur. There were 12 sites for each of the four categories resulting in 48 total. Daubenmire 1m2 plots were placed haphazardly throughout the site. Native relative cover, Shannon\u27s H, native richness, non-native relative cover, non-native shannons, and non-native richness were assessed. There was a site effect for native relative cover, native Shannon’s H, native richness, non-native relative cover, and non-native richness. There was a treatment effect for native relative cover, non-native relative cover, non-native Shannon’s H, and non-native richness. There was a site by treatment interaction for native relative cover, non-native relative cover, non-native Shannon’s H, and non-native richness. The data show that for four of the five sites, the total relative native cover was higher when there was a lower presence of A. petiolata. All five sites had lower non-native Shannon’s H when A. petiolata was present. From the results, it can be determined that A. petiolata significantly impacts the native species of an herbaceous understory. These results correlate with the literature, as A.petiolata can compete with native species, especially in areas with higher disturbances, and lead to less ecosystem diversity
The Role of Leaf Decomposition in Macroinvertebrate Colonization
Get PDFDecomposition plays an important ecological role in carbon and nutrient cycling that supply food and energy resources to food webs. This study investigates the potential role that leaf decomposition of different leaf species may play in macroinvertebrate assemblages in upper Midwest streams. We hypothesized that the different decomposition rates experienced with different leaf species and in different streams would have an effect on invertebrate colonization due to the variance in nutrient availability. Due to altered fire regimes and other influences, forests are experiencing declines in fire-adapted, heliophytic species such as oaks and compositional shifts toward shade-tolerant, mesophytic species such as maples. This compositional shift in forest species, also known as Mesophication, may have implications for macroinvertebrate communities. Sugar Maple (Acer saccharum) and Bur Oak (Quercus macrocarpa) leaves were chosen to test the effect of their decomposition on invertebrates due to their prevalence in the Midwest, research supporting their expected difference in decomposition rates, and implications for Mesophication. Dried leaves were placed into 60 mesh bags (30 of each leaf species) with a starting dry mass of 5g ± 0.1, into three different streams for 22 days. Mass loss was measured to quantify decomposition rates and macroinvertebrates within each mesh bag were collected and identified to the family level. In agreement with past research, Sugar Maple leaves decomposed significantly faster than Bur Oak leaves. Leaf decomposition rate varied significantly across the experiment (ANOVA, F= 55.428, p= 0.000) and was strongly impacted by leaf type (ANOVA, F=264.449, p=0.000) and by stream (ANOVA, F=5.640, p=0.006) . However, contrary to our hypothesis, leaf type did not have an effect on invertebrate communities observed in the leaf bags in terms of abundance, Simpson’s diversity, Shannon’s diversity, or Family Biotic Index. Likewise, stream did not have an effect on macroinvertebrate indices, except for richness (ANOVA, F=5.047, p=.010). Invertebrate assemblages in all streams were dominated by predator and collector/gatherer taxa. Overall, leaf type did not have a significant effect on macroinvertebrate communities found colonizing the leaf packs despite the leaf types significant difference in decomposition rates. A possible explanation for this lack of effect is that the numerically dominant predator and collector/gatherer taxa may rely on leaf types for habitat or protection from predators as opposed to being directly involved in the decomposition process like shredders (which were rare in all streams). Further research might include allowing for a longer decomposition time to look for the impact of later colonizing species or species that may differ in preference once the difference between leaf types becomes more pronounced later in decomposition
Provenance of the Northern Range, Trinidad Using Detrital Zircon U-Pb Geochronology: Implications for Northern South American River System Paleogeography
Get PDFThe Northern Range of Trinidad is located in a key area for evaluating the Mesozoic-Cenozoic evolution of the Caribbean and South American plates. Here, we present detrital zircon U-Pb geochronology for 2391 grains from ten samples collected from metasedimentary rocks of the Northern Range. These data are used to bracket the maximum depositional age of the fossil-poor metasedimentary rocks from the Northern Range and to investigate the provenance of their sedimentary protoliths. Detrital zircon ages range between 3136.5 ± 22.9 Ma and 139.0 ± 5.4 Ma, reflecting apparent contribution from a variety of crustal affinities; however, since the youngest ages are 199.5 ± 7.4 Ma to 139.0 ± 5.4 Ma, it is unlikely that sediments were sourced from the Caribbean Plate, which is ca. 88 Ma. Samples from the western Northern Range exhibit significant peaks clustering around 1.0 Ga, suggesting a prominent Grenville basement sediment source. In contrast, samples from the eastern Northern Range have bimodal peaks at ca. 1.4 Ga and 1.75 Ga, which overlap with Central Amazonian crustal ages. Central Northern Range rocks exhibit a single, well-constrained peak at ca. 2.0 Ga, which may be associated with Eburnean- West African to Northern-Central Amazonian terranes. While all samples show significant contributions from the South American craton, suggesting this was their primary sedimentological source, potential source area changes were explored because samples were collected from different structural horizons. These results are among the first to quantify the maximum depositional age of the metasedimentary rock and indicate that the youngest Northern Range clastic sediments were deposited in the Early Cretaceous (Valanginian). Based on the high frequency of detrital zircons from the western interior of South America, our data suggest that the proto-Orinoco River may have begun draining to the northeast coast of South America earlier than previous research suggests