Digital Commons Network^™

Afforestation And Biodiversity: Bryophyte Richness Changes Between Icelandic Forest Types, Kian Mcdonough

Independent Study Project (ISP) Collection

Forest-dwelling bryophytes (mosses, liverworts, hornworts) greatly contribute to biodiversity and ecosystem function but are largely under-studied in comparison to vascular plants. With Iceland’s large-scale afforestation efforts there is a need to understand how different afforestation species are affecting biodiversity, including bryophyte diversity. This study looked at differences in ground-floor bryophyte richness across Sitka spruce, lodgepole pine, and downy birch forests and found that bryophyte richness was highest in the Sitka spruce forests and lowest in downy birch forests. While this suggests a negative correlation between bryophyte richness and light availability, since the conifer species have the densest copy cover, other …

Next-Generation Technologies Unlock New Possibilities To Track Rangeland Productivity And Quantify Multi-Scale Conservation Outcomes, Caleb P. Roberts, David E. Naugle, Brady W. Allred, Victoria M. Donovan, Dillon T. Fogarty, Matthew O. Jones, Jeremy D. Maestas, Andrew C. Olsen, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

Historically, relying on plot-level inventories impeded our ability to quantify large-scale change in plant biomass, a key indicator of conservation practice outcomes in rangeland systems. Recent technological advances enable assessment at scales appropriate to inform management by providing spatially comprehensive estimates of productivity that are partitioned by plant functional group across all contiguous US rangelands. We partnered with the Sage Grouse and Lesser Prairie-Chicken Initiatives and the Nebraska Natural Legacy Project to demonstrate the ability of these new datasets to quantify multi-scale changes and heterogeneity in plant biomass following mechanical tree removal, prescribed fire, and prescribed grazing. In Oregon’s sagebrush …

Intestinal Microbiota Analysis Of Broiler Chickens Under Necrotic Enteritis Challenge And Tributyrin Supplementation, Taylor Nicole Mckinney

Graduate Theses and Dissertations

Poultry is a staple protein source for most of the planet. Until recently, antibiotic growth promoters (AGPs) were used to prevent illnesses in commercial chicken production. Currently, this is not possible due to regulations and consumer concern, but without such a preventative, diseases like necrotic enteritis (NE) have reemerged, posing a threat to bird health, and ultimately, our food source. Necrotic enteritis is a severe gastrointestinal disease caused by the gram-positive pathogen, Clostridium perfringens. Clinical features of this disease are diarrhea, intestinal lesions, and death, with a high transmission rate. In a subclinical form, growth performance is diminished and is …

The Microbial Nitrogen Cycling, Bacterial Community Composition, And Functional Potential In A Natural Grassland Are Stable From Breaking Dormancy To Being Dormant Again, Bikram Kumar Das, Satoshi Ishii, Linto Antony, Alexander Smart, Joy Scaria, Volker Brozel

Native Plant Focused Publications

The quantity of grass-root exudates varies by season, suggesting temporal shifts in soil microbial community composition and activity across a growing season. We hypothesized that bacterial community and nitrogen cycle-associated prokaryotic gene expressions shift across three phases of the growing season. To test this hypothesis, we quantified gene and transcript copy number of nitrogen fixation (nifH), ammonia oxidation (amoA, hao, nxrB), denitrification (narG, napA, nirK, nirS, norB, nosZ), dissimilatory nitrate reduction to ammonia (nrfA), and anaerobic ammonium oxidation (hzs, hdh) using the pre-optimized Nitrogen Cycle Evaluation (NiCE) chip. Bacterial community composition was characterized using V₃-V₄ of the …

Ecological Study Of Iris Unguicularis Cretensis In The Coastal Region Of Syria في المنطقة الساحلية من سورية (Iris Unguicularis Cretensis) دراسة بيئية لنبات سوسن كريت, Zuheir Shater, Tharwat Ibrahim, Mohammad Korbaissa

Arab Journal of Arid Environments المجلة العربية للبيئات الجافة

This search was conducted during 2014 - 2017 in order to determine the distribution area of Iris unguicularis cretensis in the coastal region of Syria, to evaluate the current situation of its habitats, and to determine the best method to reproduce this plant and evaluate its nutritive value as forage. The distribution area was identified through 12 field trips at various types of parent rocks, expositions, and altitudes along the western versant of the coastal mountains in Syria. The properties of natural habitat was examined in 37 samples distributed along a gradient extending from 300 to 1000 m above sea …

Volume 2, Chapter 19-3: Bryophyte Defenses Against Bacteria, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Relationships Between Biodiversity And Production In Grasslands At Local And Regional Scales, A. Hector, M. Loreau

IGC Proceedings (1997-2023)

Key points

1. Experimental manipulations of plant species diversity in unfertilised prairies and meadows has revealed that increasing diversity often leads to increased productivity (range of observed relationships varies from flat to log-linearly positive); driven by a combination of facilitation, niche-partitioning and sampling/selection effects.

2. The longer-term effects of diversity on ecosystem stability are not as clear and in need of further work.

3. Recent applied work, and a new review of the grassland literature, both show the potential for biodiversity to increase productivity under realistic field conditions.

4. The longer-term feedback of grazers on biodiversity gradients is unknown, and …

Global Atmospheric Change And Its Effect On Managed Grassland Systems, Andreas Lüscher, J. Fuhrer, P. C. D. Newton

IGC Proceedings (1997-2023)

Key points

1. Increasing atmospheric CO2 concentration and a trend to warmer mean temperatures are the most reliable aspects of global atmospheric change. Projections of the extent of climate change and the frequency of extreme weather conditions remain uncertain.

2. Research has considerably reduced the uncertainty about effects of global atmospheric change on physiology of plants, productivity and species composition of plant communities.

3. Other factors (e.g. nutrient availability, soil type) and long-term adaptation of the ecosystem (e.g. nutrient cycling and sequestration) influence the response of plant communities to global atmospheric change. Generalisation is not possible with respect to the …

Potential Of C4 Tropical Grasses To Contribute In Carbon Sequestration, Environmental Security And Livelihood Opportunities Through Increased Fodder Availability, D. R. Malaviya, A. K. Roy, P. Kaushal

IGC Proceedings (1997-2023)

The world grasslands/rangeland ecosystems comprise 26% of earth’s surface and have immense ecological and economic significance. Diversity of grasslands had been a key element for their sustainability. Grasslands in India have existed as natural ecosystems for millions of years. It is a major source of income, employment and livelihood to the rural families. Owing to heavy grazing pressure, coupled with other social/anthropogenic factors, the grazing resources have fast deteriorated. The country has many old and natural grasslands with ethnic and economic value. Comprehensive ecological studies including floristic compositions, dominant species, grazing pressure and the climax/sub-climax stages of ecological succession will …

Population Ecology Of A Caribbean Epiphyte Trichocentrum Undulatum (Orchidaceae): Defining Habitat And The Effects Of Herbivory And Hurricanes At Its Peripheral And Core Range, Haydee Borrero

FIU Electronic Theses and Dissertations

Population ecology studies are central to species conservation. My dissertation focused on the Florida state-listed endangered orchid, Trichocentrum undulatum at its northern-most range in the Everglades National Park (ENP), Florida and multiple populations throughout its core range in Cuba. Through surveying populations of T. undulatum across this range from 2013-2021, I made a new reporting on the occurrence of a specialized insect herbivore, Melanagromyza miamensis in Cuba (Chapter 1). This flower-crippling herbivore was previously known only in the ENP. With this discovery I assess the intensity and impacts of this herbivore, as well as others on T. undulatum across the …

Forb Counts In Grassland Are Sensitive To Analytical Method, Gene A. Fults

IGC Proceedings (1997-2023)

An analysis of forbs from 9 years of Plant Census protocol (NRI 2019) is compared to data from the Line Point Intercept (LPI) protocol. Both protocols were conducted on the same geospatially separate macroplots (N=1230). The macroplots locations were stratified by NRI based on a land hierarchy which has had long-term use in the United States (Salley etal 2015). This ties vegetation and land together in the data. The analysis showed that the 15-minute plant census method increased forb species data by 29 percent over the LPI method which takes 40-60 minutes. Both methods captured similar total ratios and rank …

Characterizing Invasiveness Through A Descriptive Study Of Guinea Grass (Megathyrsus Maximus) Growing In Three Habitat Types And Differing Herbivore Assemblages In Both Kenya And Texas, A. C. Rhodes, R. M. Plowes, D. J. Martins, I. Ng'iru, L. E. Gilbert

IGC Proceedings (1997-2023)

Guinea grass (Megathyrsus maximus syn. Panicum maximum) is an important pasture grass that has been introduced pantropically, yet in many cases has escaped cultivation and is invading native rangelands – threatening biodiversity at multiple trophic levels. An increasing challenge of rangeland management is balancing the importance of pasture grasses with their negative impact on ecosystem processes. Given this challenge, it is critical to understand the mechanisms that underlie grass invasion. In this descriptive study, our objective was to assess the ecological stress release hypothesis by comparing the relative abundance and functional traits of Guinea grass in Kenya's home …

An Integrated Framework To Study Ecological Tipping Points In Social-Ecological Systems, F. A. Männer, L.-M. Schwarz, D. A. Menestrey-Schwieger, V. Amputu, M. C. Bilton, K. Brinkmann, G. Dressler, N. Hamunyela, H. Heita, S. Heshmati, S. Liehr, M. Mbidzo, F. Munyebvu-Chambara, W. C. Nesongano, M. Rauchecker, A. Sandhage-Hofmann, K. Tielbörger, K. Zimmer, A. Linstädter

IGC Proceedings (1997-2023)

Sudden regime shifts or tipping points pose a major threat to various ecosystems and people's livelihoods worldwide. However, tipping points are still hard to predict and often occur without warning. To avoid dramatic social-ecological consequences, it is crucial to understand tipping point behaviour and to identify early warning indicators. Previous studies have hardly implemented an integrated social-ecological approach, which has led to a fragmented understanding and oversimplification of tipping point phenomena. Against this background, we present a systemic research framework that harmonizes ecological and social perspectives to gain a mechanistic understanding of tipping point behaviour. We utilize a social-ecological systems …

Volume 4, Chapter 1-20: Aquatic And Wet Marchantiophyta, Class Marchantiopsida: Conocephalaceae, Part 1, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Volume 4, Chapter 18-5: Caves - Caverns, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana

Williams Honors College, Honors Research Projects

Ohio forests are threatened by the invasive ecosystem engineer A. agrestis. A. agrestis invasion typically co-occurs with the ecosystem engineer, Odocoileus virginianus, where their impacts may synergize. To determine the direct effects of A. agrestis invasion, fenced plots across the Cuyahoga Valley National Park that excluded deer were utilized. The species richness, Shannon diversity and evenness of woody understory flora was measured in each plot. Mustard extraction was used to determine earthworm abundance. Correlations between abundance and measured variables were used to highlight potential invasion effects. Abundance and species richness was found to have a significant, positive correlation (p = …

Review Of Methods For Ecological Research On Terrestrial Small Mammals, By Robert Mccleery, Lynda R. Lafond

The Prairie Naturalist

Small mammals are used in ecological studies throughout the world, yet the subject has lacked a clear reference that included upto- date methods pertaining to passive detection, molecular, and statistical approaches. In Methods for Ecological Research on Terrestrial Small Mammals, McCleery and his coauthors build on previous research references (Braun 2005, Sutherland 2006, Krebs 2014, Silvy 2020) and present methodologies specific to the study of small mammals that are applicable globally. Written as an asset for novice and experienced small mammal researchers alike, Methods for Ecological Research on Terrestrial Small Mammals is organized in a logical format, providing readers …

Industrial Hemp As A Resource For Birds In Agroecosystems: Human–Wildlife Conflict Or Conservation Opportunity?, Emily A. Kotten, Iona Hennessy, Bryan M. Kluever, Zachary T. Brym, Bradley F. Blackwell, Lee A. Humberg, Page E. Klug

Human–Wildlife Interactions

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …

Quantifying Contributions Of Climate, Geography, And Gene Flow To Divergence: A Case Study For Three North American Pines, Constance E. Bolte

Theses and Dissertations

Long-lived species of trees, especially conifers, often display weak patterns of reproductive isolation, but clear patterns of local adaptation and phenotypic divergence. Discovering the evolutionary history of these patterns is paramount to a generalized understanding of speciation and the processes that confer population persistence versus those that compromise adaptive potential under rapidly changing environments. Forest trees have long generation times and low migratory potential making them especially vulnerable to population fragmentation and reductions of genetic diversity due to insufficient tracking of niche optima and adaptational lags. Within clades of the genus Pinus, evolutionary histories appear to be riddled with hybridization …