Physical Sciences and Mathematics Commons^™

Adaptation And Utilization Of Three Legume In China, Huang Wenhui

IGC Proceedings (1977-2023)

China is a vast territory with extremely varied climates, soil, and topography, and it is very rich in pasture grass resources. The main legumes for forage are Alfalfa (Medicago sativa L.), yellow alfalfa (Medicago folcata L.) and shadawang (Astragalis adsurgent Pall.)

Preliminary Evaluation Of Legume Germ Plasm In The Cerrados Of Brazil, D Thomas, R P. De Andrade

IGC Proceedings (1977-2023)

In 1978 an evaluation program was initiated to select legumes that (1) grow and produce seed on acid soils under aluminum and water stress, (2) persist under grazing, and (3) tolerate pests and diseases. The work is being conducted at the Cerrados Agricultural Research Center, near Brasilia, at lat 15°S and altitude 1,000 to 1, 100 m . Annual rainfall is 1,500 mm, mostly distributed in a 6-month wet season, and mean annual temperature is 21°C. Nine hundred legume accessions from thirteen genera have now been established as spaced plants on the 2 major soil types of the region. The …

Genetics And Utilization Of Apomixis For The Improvement Of Guineagrass (Panicum Maximum Jacq.), Y H. Savidan

IGC Proceedings (1977-2023)

Natural polymorphism in guineagrass (Panicum maximumjacq.) has been stabilized in tetraploid biotypes by apomixis. Sex­ual diploids were found in East African populations. Our objective was to determine whether apomixis could be related with a simple genetic background and manipulated in an improvement program. Apomicts of guineagrass are characterized by a 4-nucleate embryo sac structure, and this trait was used in genetical analyses to differentiate apomictic from sexual hybrids. Progeny tests were also conducted as controls. Ten different types of progenies were analyzed: tetraploid sexual (from colchicine treatment of diploids) x apomictic F1 hybrids; selfed and backcrossed progenies of sexual F1 …

Breeding Challenges In Apomictic Warm-Season Grasses, E C. Bashaw, P W. Voigt, B L. Burson

IGC Proceedings (1977-2023)

Efforts to breed apomictic grasses met with little success in the past, but results of more recent research show significant progress with some species and new prospects for improving apomicts. Early research uncovered the cytological basis for apospory and diplospory, found the common apomictic mechanisms in grasses, and showed that apomixis is transmitted from pannt to offspring. Discovery of sexual or partially sexual (facultative apomicts) plants in several species formerly considered obligate apomicts allowed for hybridization and genetic studies. Results of subsequent research confirmed inheritance of apomixis, and data from the more conclusive studies indicate that method of reproduction …

Visualizing Ozone Pollution In The Denver Metro Area Using A Bioindicator Garden, Ella K. Mathews, Hillary Hamann, Julie Morris, Erica L. Larson

DU Undergraduate Research Journal Archive

Since the industrial revolution, widespread fossil fuel combustion has significantly increased atmospheric pollution. The combustion of fossil fuels releases nitrogen oxides (NOx) and volatile organic compounds (VOCs), which form tropospheric (ground-level) ozone when exposed to sunlight. Ozone directly harms plants by disrupting their ability to absorb carbon dioxide, release oxygen, and carry out photosynthesis. Bioindicator species are plants that have visible responses to environmental conditions, such as ozone, and can act as “canaries in the coal mine,” indicating the health of their environment. In this study, we used a garden of ozone bioindicator species (ozone garden) as a cost-effective tool …

Assessing Vegetation Health Following The 2014 Carlton Complex Fire Using Remote Sensing, Rachael Sv Pentico

2026 Symposium

Climate change, combined with decades of altered fire regimes and fire suppression, has increased fuel accumulation across western U.S. forests, contributing to more frequent, larger, and more intense wildfires. Remote sensing offers an effective approach for analyzing these large-scale fire events and their ecological impacts, as satellite imagery enables affordable, accessible, and reproducible monitoring of vegetation change across broad spatial and temporal scales. This study examined the 2014 Carlton Complex Fire in the Methow Valley, Washington. Burning 265,108 acres, it was the largest wildfire in Washington State history at the time and caused extensive agricultural and forest damage. Post-fire vegetation …

Bottles, Butterflies, And Biomass: Recycled Glass Sand, Microbial Additions, And Herbivory Effects On Milkweed Growth, Kealey Skinner

Honors Theses

Plant-soil-microbe interactions are integral components of ecological networks and drive ecosystem function from the bottom-up. Whereas herbivores regulate ecosystem function from the top-down, having opposing and potentially complementary effects on ecosystem function. My thesis sought to understand how below-ground microbial communities contribute to herbivore preference and plant biomass across varied soil substrates. My thesis asked: how do substrate and soil microbial communities influence herbivore preference and plant biomass accumulation on swamp milkweed (Asclepias incarnata)? To address this question, seedlings of A. incarnata were sown in 2.5 cm wide × 10 cm deep pots filled with either natural beach sand or …

Herbivory Of Phragmites Australis Along A Salinity Gradient In Connecticut Wetlands, Sydney H. Kolz

Honors Scholar Theses

Invasive Phragmites australis (common reed) is widely distributed in New England wetlands, where it often outcompetes native plants and decreases biodiversity throughout the food web. Controlling its invasion is a priority, especially in salt marsh habitat, but current management techniques are inefficient. Leveraging natural processes may improve control strategies, but in order to do so, we must first better understand how abiotic and biotic stressors interact and affect Phragmites. This study focuses on herbivory and salinity, two factors limiting Phragmites’ fitness. I measured soil salinity and quantified the damage of three herbivore guilds (i.e. gall-formers and stem-borers, leaf-chewers, and …

Passive Microwave Remote Sensing Of Flash Drought Impacts On Vegetation, Quinton R. Deppert

School of Natural Resources: Dissertations, Theses, and Student Research

In 2002, Dr. Mark Svoboda characterized a new form of drought known as flash drought. Flash drought was defined as a rapid decline in vegetation health caused by severe heat and drought. In recent years, attempts to quantify the impacts of flash drought via precipitation, soil moisture, evapotranspiration, and temperature indicators have proliferated. What has rarely been quantified is what the rapid decline in vegetation health amid flash drought looks like through remote sensing. This is because vegetation health indices like the Normalized Difference Vegetation Index (NDVI) are derived from the visible and infrared regions of the electromagnetic spectrum and …

Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach

Theses and Dissertations

Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …

Response Of Chlorophyll, Morphology, And Yield Of Several East Java Superior Soybean (Glycine Max L.) Varieties To Levels Of Salinity, Puji Lestari Tarigan, Ida Retno Moeljani, Fadila Suryandika, Hadi Munarko

Jurnal Kultivasi

Soybean production has been extended to saline areas. This development is a strategy to expand planting areas to suboptimal land to increase worldwide production. To support cultivation in these locations, it is necessary to develop superior varieties that are resistant to salinity and provide supporting technological inputs. In saline conditions, soybeans may face stress that leads to morphological, physiological, and yield disturbances. Consequently, the response of several soybeans in East Java should be observed. This study is a pot experiment and arranged in a Factorial Completely Randomized Design (CRD) consisting of two factors, soybean varieties and NaCl concentrations. The treatments …

Testing The Intermediate Disturbance Hypothesis On Anthropogenic Pressure In Central Alabama, Gavin Terrell

Theses

Biodiversity is fundamental to maintaining ecosystem structure and function globally. Prior to the late 20th century, ecological theory generally predicted that biodiversity would be highest in systems experiencing minimal disturbance. However, Joseph H. Connell challenged this view with the Intermediate Disturbance Hypothesis (IDH), which posits that species diversity peaks at intermediate levels of disturbance and declines under conditions of both low and high disturbance. Although widely cited, the applicability of the IDH to natural systems remains debated, particularly in the context of anthropogenic disturbances and when diversity is measured beyond species richness alone.

This study evaluated the predictions of the …

Clerodendrum Kelli (Lamiaceae), A New Species From Carranglan, Nueva Ecija, Philippines, And Lectotypification Of Clerodendrum Mindorense, David Justin R. Ples, Jacek Patykowski, John Charles A. Altomonte, Adriene B. Tobias, Rene Alfred Anton Bustamante

Biology Faculty Publications

Clerodendrum kelli (Lamiaceae), a new species from the montane forests of Carranglan, Nueva Ecija, Philippines, is described and illustrated. The species shares morphological features with Clerodendrum quadriloculare and C. mindorense, but differs in inflorescence structure, corolla tube length, and calyx shape and color. A lectotype for C. mindorense is also designated. Preliminary conservation assessment places C. kelli in the Critically Endangered category (CR B1ab(iii)+2ab(iii)). This study contributes to Philippine plant biodiversity knowledge and informs conservation strategies.

Nepenthes Megastoma (Nepenthaceae), A Micro-Endemic Pitcher Plant From Puerto Princesa Subterranean River National Park, Palawan, Philippines, John Charles A. Altomonte, John Paul R. Collantes, Vernaluz Mangussad, Rene Alfred Anton Bustamante, Alastair S. Robinson

Environmental Science Faculty Publications

Nepenthes megastoma is described and illustrated as a new species from the Puerto Princesa Subterranean River National Park, a UNESCO World Heritage Site in Palawan Philippines. This carnivorous tropical pitcher plant is currently known from just three locations in the Mount Saint Paul karst formation, where it grows on vertical limestone walls. Morphologically, N. megastoma is characterised by its highly branched stems, campanulate pitchers, peltate tendril exsertion, dimorphic upper pitchers, and unidirectionally upturned female flowers. It is assessed as Critically Endangered under the IUCN Red List criteria, based on its restriction to three subpopulations comprising few total individuals. Pitcher morphology …

Seagrass Persistence In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly Kibler, Melinda Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_seagrasspersistence_IRL_LWL.shp was created with support from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon (IRL) and Lake Worth Lagoon (LWL). The dataset presented herein represents persistence of seagrass throughout waters of the IRL and LWL.

Understanding The Spread Of Black Sigatoka Disease: A Deterministic And Stochastic Modeling Approach, Bernard Asamoah Afful, Luis F. Gordillo

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Modeling The Probability Of N Clonal Rosettes In A Bromeliaceae Genetic Individual, Erin N. Bodine, Layla K. Lammers

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Living Shoreline Prioritization And Hydrodynamic Habitat Suitability Models For Restoration In The Indian River Lagoon And Lake Worth Lagoon, Florida, Kelly M. Kibler, Melinda J. Donnelly, Vincent Encomio, Madison Giuntoli, Manisha Thenuwara, Brice Bennett, Laura Andrade Barron, Mariam Sonbol, Wynter Raine Seppala, Namritha Ramakrishnan, Jennifer Jordan Báez, Beth Orlando, Irene Arpayoglou, Melissa Meisenburg

Indian River Lagoon Shorelines

The spatial dataset: UCF_shorelinemodel_IRL_LWL.shp, was created with support from the Indian River Lagoon National Estuaries Program and Florida Sea Grant. These projects cumulatively led to creation of a living shoreline restoration prioritization model and hydrodynamic habitat suitability models for 1,550 km (963 miles) of estuarine shorelines in Indian River Lagoon and Lake Worth Lagoon.

The dataset presented herein includes:

1. shoreline data from >15,000 transects collected in the field,
2. shoreline wave climate data created through hydrodynamic modeling and frequency analysis of historic data,
3. categorization of potential risk for shoreline boat wake impact,
4. persistence of seagrass within 210 m of the shoreline, …

Genetic Engineering For Pastures, W J. Peacock

IGC Proceedings (1977-2023)

The first genetically engineered food products from horticultural production systems are now entering the mnrke< and field trials of genetically engineered crop species are well advanced. We cnn expect that a range of crop cultivars, in which gene

Grassland For Sustainable Ecosystems, Malcolm Hadley

IGC Proceedings (1977-2023)

Grasslnnds present many advantages for examining issues related to sustainability. Grasslands include planted pastures as well as a variety of natural rangelands in situations ranging from semi-arid to subhumid. Diversity is also reflected in the spectrum of grassland users and uses, for example, nomadic pastoralism, extensive ranches, intensive pastures, wildlife tourism, game hunting. And in terms of sustainability of resource management, grasslands encompass a wide range of contrasting situations and conflicts in resource use. Heavy grazing pressure associated with increasing human populations in certain tropical savannas, the implications of rural depopulation to traditional pasture management in alpine regions, and the …

Grasslands For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world's grazing lands are a finite resource and, overall, arc being badly managed; in most developing countries action is required now, before it is too late. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will continue locally but, for much of what is now natural pasture, exploitation by the grazing animal .will remain the major means of obtaining an economic return; the task of grassland professionals is to assist the managers of …

Human Impact On Terrestrial Ecosystems - What We Know And What We Are Doing About It, H A. Mooney

IGC Proceedings (1977-2023)

At present the impact of humankind on the Earth System is substantial and will become greater as we continue to add over 80 million people to the global population each year. Collectively the human species utilises over a third of the total fresh water that is available, as well as an equivalent amount of the total terrestrial productivity. Possil energy is being consumed at a prodigious rate and fuels, among other things, over a half a billion vehicles. To support the large human population the Earth has been greatly reconfigured with much of the land utilised for grazing and agriculture. …

Science And Information For Our Grasslands, G A. Nores, R R. Vera

IGC Proceedings (1977-2023)

This paper favours a view of grasslands, and agricultural research in general, that extends well beyond the limits of the scientific community and promotes the active involvement of scientists in current societal debates from a scientific perspective. It is argued that in developed countries environmental concerns rather than production growth will tend to dominate future social debate. In developing countries there is a need to balance agricultural growth with responsible management of natural resources. Needs for new technology go beyond improving biophysical efficiency, and involve economic and social efficiency objectives. The relevance of grassland research is assessed in terms of …

Vegetation Dynamics In Grazed Systems: A Hierarchical Perspective, D D. Briske

IGC Proceedings (1977-2023)

Grassland vegetation consists of a series of hierarchical levels including the tiller, plant, population and community which collectively influence the productivity and stability of grazed systems. These hierarchical levels may respond uniformly to influence vegetation dynamics, but frequently additional complexity is encountered by the occurrence of opposing responses between or among hierarchical levels. Consequently, it is important to con­sider responses at several hierarchical levels to achieve an accurate interpretation of vegetation dynamics to graz­ing within the community. The significance of a hierarchical perspective to vegetation management is illustrated with examples from bunchgrass dominated rangelands at the level of the individual …

Forage Conservation And Physico-Chemical Conversion, E Zimmer

IGC Proceedings (1977-2023)

The factors on which the digestibility of organic matter (dMO) of forages depend are now well-known. In temperate forages, this digestibility depends mainly on the growth stage, the rank of the growth-cycle, and the botanical species. It is constantly decreasing with advancing age, especially during the first growth-cycle. In after­math growth-cycles, high temperatures accelerate the decrease of digestibility with age. Tropical forages follow the same laws, but tropical grasses are less digestible than cool-season grasses, especially at young stages and in warm weather. This is partly due to the fact that high temperatures increase cell-wall contents and lignification, and also …

The Feeding Value Of Forages, C Demarquilly

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

Nitrogen Fixation, Cycling, And Utilization, P M. Murphy, M T. Sherwood

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

La Prairie Dans Ses Usages Multiples: Conservation Des Sols, Protection De L'Environnement, Etc., M Skouri, J Poissonet

IGC Proceedings (1977-2023)

Les terres :i paturage couvrent une partie importante de la planete et presentent une extreme diversite de situations en fonction des conditions ecologiques et des facteurs socio-economiques et culturels qui s'exercent sur ces espaces. Ces facteurs ont engendre des transformations du milieu nature] permettant d'intensifier, et :i ]'extreme, de contr61er la production vegetale de ces ecosystemes. Si le role premier de ces formations herbacees a ete d'alimenter Jes herbivores afin que l'homme en obtienne une production (viande, lait, peaux, etc.), Jes autres fonctions de ces espaces ont une importance que !'on ne peut se permettre de negliger, que ce soit …

Quickening Snow Melting In Early Spring With Black Powder In Snowy District, A Imai

IGC Proceedings (1977-2023)

Experiments were conducted during 1977-1980 to quiken snow melting in early spring with three kinds of black powders at 450 m a.s.l.,Tsunan-machi, Niigata Prefecture. Snow melting materials involved blast furnace slag, di-amido lime and calcium silicate and their effects on snow melting were compared with each other at various application rates on snow surface in late March every year. Snow melting was earlier with 600 kg/ha di-amido lime resulting from lower albedo of 25 % and it could quicken the snow-off by 10-13 days as compared to the control plot. This early snow melting induced the higher soil temperature and …

Effect Of Fertilization In Autumn Or After Wintering On Dallisgrass Production In The Following Season, T Kobayashi

IGC Proceedings (1977-2023)

To improve dallisgrass (Paspalum dilatatum Poir.) pasture productivity, the effects of autumn or spring topdressing in a field experiment and autumn nitrogen (N) application levels in a pot experiment on the regrowth and carbohydrate accumulation until winter and on the early summer production were studied. Dallisgrass pasture was topdressed in either autumn (late September) or spring (early March) at 0.5 kg/a each of N, phosphate (P2O5), and potash (K20), after the final cutting in late September 1978. Plants in pots were topdressed at the rates of 0.5, 1, 2, and 4 kg N/a, just after cutting in early October …