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Full-Text Articles in Life Sciences

Use Of Auto-Germ To Model Germination Timing In The Sagebrush-Steppe, William C. Richardson, Dallin R. Whitaker, Kyler P. Sant, Nicholas S. Barney, Ryan S. Call, Bruce A. Roundy, Zachary T. Aanderud, Matthew D. Madsen Nov 2018

Use Of Auto-Germ To Model Germination Timing In The Sagebrush-Steppe, William C. Richardson, Dallin R. Whitaker, Kyler P. Sant, Nicholas S. Barney, Ryan S. Call, Bruce A. Roundy, Zachary T. Aanderud, Matthew D. Madsen

Articles

Germination timing has a strong influence on direct seeding efforts, and therefore is a closely tracked demographic stage in a wide variety of wildland and agricultural settings. Predictive seed germination models, based on soil moisture and temperature data in the seed zone are an efficient method of estimating germination timing. We utilized Visual Basic for Applications (VBA) to create Auto‐Germ, which is an Excel workbook that allows a user to estimate field germination timing based on wet‐thermal accumulation models and field temperature and soil moisture data. To demonstrate the capabilities of Auto‐Germ, we calculated various germination indices and modeled germination …


Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney Aug 2018

Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney

Electronic Theses and Dissertations

Oak savannas were once an abundant vegetation type in the Midwestern United States that have now declined to <1% of their original distribution. Historically, natural disturbances such as periodic fire and grazing maintained oak savannas, but these have been reduced or eliminated, resulting in woody encroachment and subsequent habitat loss and degradation. In 2009-10, a baseline, pre-restoration study was completed to determine vegetation characteristics, breeding bird abundances, nest success, and nest site selection at the Gus Engeling Wildlife Management Area (GEWMA) in eastern Texas. The results showed a lack of savanna vegetation structure on degraded sites and few savanna or grassland obligate bird species. The goal of this study was to determine how breeding birds of oak savanna vegetation types in eastern Texas respond to restoration effects 7 years after initial management. Post-restoration surveys completed in 2016-17 showed a change in avian assemblages from a more woodland dominated community to grassland/savanna community. The presence and breeding of savanna obligate species dickcissel (Spiza americana) and lark sparrow (Chondestes grammacus) indicates that the restoration was successful. The presence of savanna species can be linked to the herbaceous vegetation that was restored to more closely resemble historic oak savanna structure and can quantify the success of restoration efforts.


Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Rangelands, Great Basin, Usa: Part I: Vegetation, Hydrology, And Erosion Responses, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Osama Z. Al-Hamdan, Patrick R. Kormos, Mark A. Weltz Apr 2018

Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Rangelands, Great Basin, Usa: Part I: Vegetation, Hydrology, And Erosion Responses, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Osama Z. Al-Hamdan, Patrick R. Kormos, Mark A. Weltz

Articles

Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment has imperiled a broad ecological domain of the sagebrush steppe (Artemisia spp.) ecosystem in the Great Basin Region, USA. As these conifers increase in dominance on sagebrush rangelands, understory vegetation declines and ecohydrologic function can shift from biotic (vegetation) controlled retention of soil resources to abiotic (runoff) driven loss of soil resources and long-term site degradation. Scientists, public land management agencies, and private land owners are challenged with selecting and predicting outcomes to treatment alternatives to improve ecological structure and function on these rangelands. This study is the …


Restoration Of Native-Dominated Plant Communities On A Centaurea Stoebe L.-Infested Site, Neil W. Macdonald, Kaitlyn M. Dykstra, Laurelin M. Martin Apr 2018

Restoration Of Native-Dominated Plant Communities On A Centaurea Stoebe L.-Infested Site, Neil W. Macdonald, Kaitlyn M. Dykstra, Laurelin M. Martin

Funded Articles

Questions: Restoring native-dominated plant communities often requires controlling invasive species, reintroducing native species, and implementing continued management practices. Can single herbicide applications to control Centaurea stoebe L. encourage establishment of seeded native species more effectively than a single mowing? Can annual hand pulling to control C. stoebe favor the persistence of seeded native species? Can mid-spring burning reduce C. stoebe and increase native forbs and grasses? After eight years, will the restored plant communities differ from those in untreated areas?

Location: Bass River Recreation Area, Ottawa County, MI, USA.

Methods: We studied the effects of site preparation (mowing, clopyralid, glyphosate), …


Improving Post-Wildfire Seeding Success Using Germination Modeling And Seed Enhancement Technologies, William Charles Richardson Apr 2018

Improving Post-Wildfire Seeding Success Using Germination Modeling And Seed Enhancement Technologies, William Charles Richardson

Theses and Dissertations

Arid and semi-arid rangelands are important ecosystems that are consistently degraded through disturbances such as wildfires. After such disturbances, the invasion and dominance of annual grasses, like cheatgrass (Bromus tectorum L.), can lead to an overall loss of ecosystem productivity and an increase in fire frequency. To reduce weed dominance, native and introduced perennials species are typically be seeded in the fall. High mortality is seen from these seeded plant communities due to germinated seed being exposed to freezing, drought, fungal pathogens, and other biotic and abiotic stressors during winter months. We utilized wet-thermal accumulation models to first further …


Understanding Soil Moisture Levels On Soledad Ridge, Santa Rosa Island, California During The Summer Months, Dulce M. Lopez, Stephen Bednar, Kathryn Mceachern Jan 2018

Understanding Soil Moisture Levels On Soledad Ridge, Santa Rosa Island, California During The Summer Months, Dulce M. Lopez, Stephen Bednar, Kathryn Mceachern

STAR Program Research Presentations

Santa Rosa Island located off the coast of Santa Barbara County was grazed by non-native ungulates leaving the island stripped of vegetation topsoil layer. With the removal of ungulates, the National Park Service began restoring the Cloud Forest on Soledad Ridge. Soledad Ridge is said to have once been covered by large stands of island oaks (Quercus tometella) and other endemic and native plants. The unique leaf and structural morphology of such vegetation collects water from wind derived fog which serves as the main source of water for this unique ecosystem. In an effort to jump-start ecosystem vegetation …


Ms Environmental Biology Capstone Project, Meghan Mcgill Jan 2018

Ms Environmental Biology Capstone Project, Meghan Mcgill

Regis University Student Publications (comprehensive collection)

This study aims to provide a deeper understanding of the role of competition in food webs, and more specifically, in trophic cascades induced by biodiversity loss. Trophic cascades are food web disturbances that result from the removal of an important species, often a predator, and lead to dramatic changes in herbivore and plant populations. It is critical to understand the mechanisms that drive and mitigate trophic cascades, because global biodiversity loss is increasing. Previous research suggests that biodiversity, specifically intraguild biodiversity with members in the same trophic level, is an important factor in reducing the negative effects of trophic cascades. …


Abscisic Acid Seed Coating Delay Data, William Richardson Jan 2018

Abscisic Acid Seed Coating Delay Data, William Richardson

ScholarsArchive Data

This data is from a study which determined the effect different application rates of abscisic acid have on the total germinability and germination time of seeds. Germination count data, calculated germination indices, and field germination predictions are all included within the data set.