Ecology and Evolutionary Biology Commons^™

Application Of Regression Model To Identify A Parameter That Best Defines Species Diversity In The Coastal Forests Of Tanzania, Cosmas Mligo

Tanzania Journal of Science

Coastal forests of Tanzania are diverse in plant species that make them included as part of the 34 world biodiversity hotspots. This study aimed atdetermining plant species diversity, richness, and evenness as well as to identify the parameter that best defines plant species diversity in the three coastal forests; namely Zaraninge, Kazimzumbwi and Pande. Transect method was used for vegetation data collection and subjected to Analysis of variance and regression techniques. The plant species composition among forests ranged between 75 and 146 with a significantly lower diversity index in Zaraninge (2.057 ± 0.112) than those in Pande (2.415 ± 0.022) …

Rapid Regeneration Offsets Losses From Warming-Induced Tree Mortality In An Aspen-Dominated Broad-Leaved Forest In Northern China, Pengwu Zhao, Chongyang Xu, Mei Zhou, Bo Zhang, Peng Ge, Nan Zeng, Hongyan Liu

Aspen Bibliography

Worldwide tree mortality as induced by climate change presents a challenge to forest managers. To successfully manage vulnerable forests requires the capacity of regeneration to compensate for losses from tree mortality. We observed rapid regeneration and the growth release of young trees after warming-induced mortality in a David aspen-dominated (Populus davidiana) broad-leaved forest in Inner Mongolia, China, as based on individual tree measurements taken in 2012 and 2015 from a 6-ha permanent plot. Warming and drought stress killed large trees 10–15 m tall with a total number of 2881 trees during 2011–2012, and also thinned the upper crowns. …

Herbivory And Eutrophication Mediate Grassland Plant Nutrient Responses Across A Global Climatic Gradient, T. Michael Anderson, Daniel M. Griffith, James B. Grace, Eric M. Lind, Peter B. Adler, Lori A. Biederman, Dana M. Blumenthal, Pedro Daleo, Jennifer Firn, Nicole Hagenah, W. Stanley Harpole, Andrew S. Macdougall, Rebecca L. Mcculley, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schütz, Eric W. Seabloom, Carly J. Stevens, Lauren L. Sullivan, Peter D. Wragg, Elizabeth T. Borer

Plant and Soil Sciences Faculty Publications

Plant stoichiometry, the relative concentration of elements, is a key regulator of ecosystem functioning and is also being altered by human activities. In this paper we sought to understand the global drivers of plant stoichiometry and compare the relative contribution of climatic vs. anthropogenic effects. We addressed this goal by measuring plant elemental (C, N, P and K) responses to eutrophication and vertebrate herbivore exclusion at eighteen sites on six continents. Across sites, climate and atmospheric N deposition emerged as strong predictors of plot‐level tissue nutrients, mediated by biomass and plant chemistry. Within sites, fertilization increased total plant nutrient pools, …

The Tensile Root Strength Of Emergent Coastal Macrophytes, Lauris Olivia Hollis

LSU Doctoral Dissertations

Spartina patens is a dominant emergent macrophyte in fresh, intermediate, and brackish marshes along the Atlantic and Gulf coasts of United States where its biomechanical properties are a key component of wetland health and resilience. Its root biomass and tensile root strength are essential for anchorage, erosion protection, and are important determinants of soil strength. Nutrients and the herbicide atrazine are suspected of negatively impacting this wetland plant and others. The objectives of this study were to: 1) ascertain the tensile root strength of five emergent coastal macrophytes in coastal estuaries, and 2) test the effects of nutrient addition, atrazine …

The Effect Of Simulated Herbivory On Pea Plants (Pisum Sativum) Under Water Stress, Georgia Harrison

Conspectus Borealis

No abstract provided.

A Model Species For Agricultural Pest Genomics: The Genome Of The Colorado Potato Beetle, Leptinotarsa Decemlineata (Coleoptera: Chrysomelidae), Sean D. Schoville, Yolanda H. Chen, Martin N. Andersson, Joshua B. Benoit, Anita Bhandari, Julia H. Bowsher, Kristian Brevik, Kaat Cappelle, Mei-Ju M. Chen, Anna K. Childers, Christopher Childers, Olivier Christiaens, Justin Clements, Elise M. Didion, Elena N. Elpidina, Patamarerk Engsontia, Markus Friedrich, Inmaculada García-Robles, Richard A. Gibbs, Chandan Goswami, Alessandro Grapputo, Kristina Gruden, Marcin Grynberg, Bernard Henrissat, Emily C. Jennings, Jeffery W. Jones, Megha Kalsi, Sher A. Khan, Abhishek Kumar, Fei Li, Vincent Lombard, Subba Reddy Palli, June-Sun Yoon

Entomology Faculty Publications

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and …

Nitrogen Fertilization Elevated Spatial Heterogeneity Of Soil Microbial Biomass Carbon And Nitrogen In Switchgrass And Gamagrass Croplands, Jianwei Li, Chunlan Guo, Siyang Jian, Qi Deng, Chih-Li Yu, Kudjo E. Dzantor, Dafeng Hui

Agricultural and Environmental Sciences Faculty Research

The effects of intensive nitrogen (N) fertilizations on spatial distributions of soil microbes in bioenergy croplands remain unknown. To quantify N fertilization effect on spatial heterogeneity of soil microbial biomass carbon (MBC) and N (MBN), we sampled top mineral horizon soils (0-15 cm) using a spatially explicit design within two 15-m2 plots under three fertilization treatments in two bioenergy croplands in a three-year long fertilization experiment in Middle Tennessee, USA. The three fertilization treatments were no N input (NN), low N input (LN: 84 kg N ha−1 in urea) and high N input (HN: 168 kg N ha−1 in urea). …

Cover Crops And Fertilization Alter Nitrogen Loss In Organic And Conventional Conservation Agriculture Systems, Rebecca E. Shelton, Krista L. Jacobsen, Rebecca L. Mcculley

Horticulture Faculty Publications

Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH₃ volatilization, N₂O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), or a mix of the two (bi-culture); (2) an organic …

Chapter 008 - Tropics, Janice M. Glime

Bryophyte Ecology Volume 4: Habitat and Role

Explore the contents of Bryophyte Ecology, Volume 4, Chapter 8 - Tropics by clicking the links above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

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. …

What Drives Species Richness In Colorado's Alpine Tundra, Michael Kintgen

Regis University Student Publications (comprehensive collection)

Despite years of research, drivers of vascular plant species richness in Colorado’s alpine tundra habitats are largely unknown. Factors such as slope aspect, Pleistocene glaciation, nutrient levels, latitude and longitude, snow depth, and disturbance have been studied. Despite this research, few patterns have emerged. Research in Colorado has been conducted on a few well studied mountains. Aridity is one factor that has not been well studied but shows promise in explaining species richness. In Patagonia and the Swiss Alps, increasing aridity correlates with higher species richness. Here, a full species assessment was conducted on nine mountains previously under researched or …

Ms Environmental Biology Capstone Project, Annamaria Marcel

Regis University Student Publications (comprehensive collection)

Due to the worldwide decline of biodiversity, protected nature reserves are necessary for species facing extinction. Many frog species have been experiencing rapid population decline and extinction due to the threat of the fungus Batrachochytrium dendrobatidis (Bd), which inflicts the highly transmittable and deadly disease chytridiomycosis. Chytridiomycosis causes increased skin tissue growth which disrupts respiration and the maintenance of water balance, which can ultimately lead to death. Certain ecological and geographical characteristics have been studied in order to assess their influence on Bd’s prevalence. Specifically, it is hypothesized that high elevations, lotic habitats, and low species richness have a positive …

Surface And Subsurface Tillage Effects On Mine Soil Properties And Vegetative Response, H. Z. Angel, Jeremy Stovall, Hans Michael Williams, Kenneth W. Farrish, Brian P. Oswald, J. L. Young

Faculty Publications

Soil compaction is an important concern for surface mine operations that require heavy equipment for land reclamation. Excessive use of rubber-tired equipment, such as scraper pans, may cause mine soil compaction and hinder the success of revegetation efforts. However, information is limited on management strategies for ameliorating the potential compacting effects of scraper pans, particularly during site preparation for loblolly pine (Pinus taeda L.) plantations. Three forms of tillage and one control were replicated five times on surface mined land in the west Gulf Coastal Plain: no tillage (NT), disking (D), single-ripping + disking (R+D), and cross-ripping + disking …

Distribution Of Glyphosate-Resistant Amaranthus Spp. In Nebraska, Bruno C. Vieira, Spencer L. Samuelson, Guilherme S. Alves, Todd A. Gaines, Rodrigo Werle, Greg Kruger

West Central Research and Extension Center, North Platte

Background: Palmer amaranth (Amaranthus palmeri S. Wats.), common waterhemp (Amaranthus tuberculatus var. rudis), and redroot pigweed (Amaranthus retroflexus L.) are major weeds occurring in fields throughout Nebraska with recurrent grower complaints regarding control with glyphosate. The objective of this study was to investigate the frequency and distribution of glyphosate-resistant Palmer amaranth, common waterhemp, and redroot pigweed populations in Nebraska. The study also aimed to investigate how agronomic practices influence the occurrence of glyphosate resistance in the three Amaranthus species.

Results: Glyphosate resistance was widespread in common waterhemp (81% of the screened populations), few Palmer amaranth …

Profitability Of Developing Beef Heifers On Stockpiled Winter Forages, Zachary David Mcfarlane, Chris Boyer, J. Travis Mulliniks

West Central Research and Extension Center, North Platte

We estimate the profitability of developing heifers on one stockpiled cool-season grass and two stockpiled warm-season grasses during the winter months by comparing distributions of net present value (NPV) over an 11-year useful life. Furthermore, distributions of payback period and the break-even price for each calf over the heifer’s production life were generated for each forage species. These results are compared across forages as well as to a simulated drylot system for heifer development. Data comes from a grazing experiment in Tennessee, where heifers grazed big bluestem and Indian grass combination (BBIG), switchgrass (SW), or endophyte-infected tall fescue (TF) pastures. …

Seedbank Persistence Of Palmer Amaranth (Amaranthus Palmeri) And Waterhemp (Amaranthus Tuberculatus) Across Diverse Geographical Regions In The United States, Nicholas E. Korres, Jason K. Norsworthy, Bryan G. Young, Daniel B. Reynolds, William G. Johnson, Shawn P. Conley, Reid J. Smeda, Thomas C. Mueller, Douglas J. Spaunhorst, Karla L. Gage, Mark Loux, Greg R. Kruger, Muthukumar V. Bagavathiannan

West Central Research and Extension Center, North Platte

Knowledge of the effects of burial depth and burial duration on seed viability and, consequently, seedbank persistence of Palmer amaranth (Amaranthus palmeri S. Watson) and waterhemp [Amaranthus tuberculatus (Moq.) J. D. Sauer] ecotypes can be used for the development of efficient weed management programs. This is of particular interest, given the great fecundity of both species and, consequently, their high seedbank replenishment potential. Seeds of both species collected from five different locations across the United States were investigated in seven states (sites) with different soil and climatic conditions. Seeds were placed at two depths (0 and 15cm) for …

Phosphorus Limitation Of Aboveground Production In Northern Hardwood Forests, Shinjini Goswami, Melany C. Fisk, Matthew A. Vadeboncoeur, Mariann Garrison-Johnston, Ruth D. Yanai, Timothy J. Fahey

All Materials

Forest productivity on glacially derived soils with weatherable phosphorus (P) is expected to be limited by nitrogen (N), according to theories of long-term ecosystem development. However, recent studies and model simulations based on resource optimization theory indicate that productivity can be co-limited by N and P. We conducted a full factorial N × P fertilization experiment in 13 northern hardwood forest stands of three age classes in central New Hampshire, USA, to test the hypothesis that forest productivity is co-limited by N and P. We also asked whether the response of productivity to N and P addition differs among species …

Hydrological Niche Segregation Defines Forest Structure And Drought Tolerance Strategies In A Seasonal Amazon Forest, Mauro Brum, Matthew A. Vadeboncoeur, Valeriy Ivanov, Heidi Asbjornsen, Scott Saleska, Luciana F. Alves, Deliane Pinha, Jadson D. Dias, Luiz E O C Aragão, Fernanda Barros, Paulo Bittencourt, Luciano Pereira, Rafael S. Oliveira

All Materials

1. The relationship between rooting depth and above‐ground hydraulic traits can potentially define drought resistance strategies that are important in determining species distribution and coexistence in seasonal tropical forests, and understanding this is important for predicting the effects of future climate change in these ecosystems.
2. We assessed the rooting depth of 12 dominant tree species (representing c. 42% of the forest basal area) in a seasonal Amazon forest using the stable isotope ratios (δ¹⁸O and δ²H) of water collected from tree xylem and soils from a range of depths. We took advantage of a major ENSO‐related …

Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori

Theses and Dissertations

Specialization on insect and animal pollinators is thought to be the driving force for the evolution of floral traits. Specifically in the New World (NW), the oil-bee pollination syndrome has led to the convergence of floral characters in two distantly related families of core eudicots, Malpighiaceae and Krameriaceae. Both families display a flag-like structure that establishes a zygomorphic flower and floral oil rewards in epithelial elaiophores. These traits work concomitantly to attract and reward female oil-bees that help fertilize these flowers and in return receive oils. The underlying genetics of floral zygomorphy were studied in several clades of core eudicots, …

Effects Of Red Clover Isoflavones On Tall Fescue Seed Fermentation And Microbial Populations In Vitro, Emily A. Melchior, Jason K. Smith, Liesel G. Schneider, Travis Mulliniks, Gary E. Bates, Zachary D. Mcfarlane, Michael D. Flythe, James L. Klotz, Jack P. Goodman, Huihua Ji, Phillip R. Meyer

West Central Research and Extension Center, North Platte

Negative impacts of endophyte-infected Lolium arundinaceum (Darbyshire) (tall fescue) are responsible for over $2 billion in losses to livestock producers annually. While the influence of endophyte-infected tall fescue has been studied for decades, mitigation methods have not been clearly elucidated. Isoflavones found in Trifolium pratense (red clover) have been the subject of recent research regarding tall fescue toxicosis mitigation. Therefore, the aim of this study was to determine the effect of ergovaline and red clover isoflavones on rumen microbial populations, fiber degradation, and volatile fatty acids (VFA) in an in vitro system. Using a dose of 1.10 mg …

Agricultural Information Needs And Food Access In The Stann Creek District Of Belize, Sam E. Harris, Donna L. Graham

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The purpose of this study was to describe agricultural information sources available to farmers and to describe food access and availability for the people of Dangriga, Stann Creek, Belize. This study used descriptive survey research methods with convenience sampling of the general public (n=22) and of farmers (n = 38) in the summer of 2017. Farmers use a variety of agricultural information sources with the extension service cited most often, followed by friends and fellow farmers. Weather, lack of information, pests, and inadequate access to capital were of primary concern for farmers. Face-to-face meetings were used most often by extension …

Large Effect Quantitative Trait Loci For Salicinoid Phenolic Glycosides In Populus: Implications For Gene Discovery, Scott A. Woolbright, Brian J. Rehill, Richard L. Lindroth

Aspen Bibliography

Genomic studies have been used to identify genes underlying many important plant secondary metabolic pathways. However, genes for salicinoid phenolic glycosides (SPGs)—ecologically important compounds with significant commercial, cultural, and medicinal applications—remain largely undescribed. We used a linkage map derived from a full‐sib population of hybrid cottonwoods (Populus spp.) to search for quantitative trait loci (QTL) for the SPGs salicortin and HCH‐salicortin. SSR markers and primer sequences were used to anchor the map to the V3.0 P. trichocarpa genome. We discovered 21 QTL for the two traits, including a major QTL for HCH‐salicortin (R2 = .52) that colocated …

The Impact Of Reconstructed Soils Following Oil Sands Exploitation On Aspen And Its Associated Belowground Microbiome, Franck Stefani, Nathalie Isabel, Marie-Josee Morency

Aspen Bibliography

Oil sands surface mining in the Athabasca region of northern Alberta (Canada) is a significant anthropogenic disturbance that resets boreal forest development and succession to early stages. During surface mining, the vegetation is cleared, the topsoil is salvaged, and the overburden (the layer of sand and clay in between the topsoil and the oil sands) is piled (see Fig. 2 in Audet et al.1 for an explanation of the land-reclamation procedure). After mining is finished, the landforms (composed of overburden and tailings sand) are capped with organic matter-rich soil covers made of either upland-derived forest floor-mineral mix (FFMM) or a …

Hart Prairie Preserve Site Visit To Assess Aspen Health Nature Conservancy, Flagstaff, Az, Amanda Grady

Aspen Bibliography

On June 11, 2018, Amanda Grady, Entomologist, Arizona Zone, Forest Health Protection, performed a site visit to evaluate aspen health on the Nature Conservancy lands at Heart Prairie Preserve (HPP) near Flagstaff. Specifically, the evaluation was to determine whether or not the aspen within exclosures on Fern Mountain have symptoms or signs of Oystershell scale (OSS), an emergent forest pest contributing to aspen decline in northern Arizona.

Effects Of Climate Change On Forest Vegetation In The Northern Rockies Region, Robert E. Keane, Mary Frances Mahalovich

Aspen Bibliography

No abstract provided.

Climate-Induced Gradients Of Populus Sp. Forest Biomass On The Territory Of Eurasia, Usoltev Vladimir Andreevich, Omid Shobairi, Chasovskikh Viktor Petrovich

Aspen Bibliography

On the basis of the compiled database in a number of 413 sample plots with determinations of forest biomass of the genus Populus sp. on the territory of Eurasia from France to southern China and Japan statistically significant transcontinental decreasing of stem, above ground and total biomass as in the direction from northern temperate to subequatorial zonal belt and in the direction from the Atlantic and Pacific coasts to the continentality pole in Siberia is established. Unlike wood story, understory biomass in these directions has not decreased, and increasing. The root: shoot ratio increases in the range between northern temperate …

Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek

Dissertations, Master's Theses and Master's Reports

Populations of invasive species are often subjected to novel selective forces in the form of anthropogenic control agents in their introduced ranges. These control agents, applied unevenly among populations within a species’ new range, can send invasive populations on drastically different evolutionary and ecological trajectories. In these studies, we aimed to see if different histories of chemical herbicide treatment are differentially influencing the genetic diversity, structure, and performance of populations of invasive watermilfoil (Myriophyllum spicatum and M. spicatum x M. sibiricum hybrids) from waterbodies in the state of Michigan. We sampled ten waterbodies with different histories of herbicide treatment …

Measured Soil Hydraulic Properties As Rzwqm2 Input To Simulate Soil Water Dynamics And Crop Evapotranspiration, Saadi Sattar Shahadha

Theses and Dissertations--Plant and Soil Sciences

Agricultural system models integrate many different processes that cannot all be measured in field experiments and help quantify soil water dynamics, crop evapotranspiration, and crop growth with high temporal resolution. Understanding soil water dynamics and crop evapotranspiration is essential to improve agricultural management of field crops. For example, the interaction between nitrogen application rate and water dynamics is not sufficiently understood. In most cases, model simulations deviate from field measurements, especially when model input parameters are indirectly and unspecifically derived. The extent to which measured soil hydraulic property inputs decrease the discrepancy between measured and simulated soil water status is …

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …

Riparian Vegetation And The Soil Seed Bank Five Years After Dam Removal On The Elwha River, Washington, Cody C. Thomas

EWU Masters Thesis Collection

Damming of rivers is widespread and can profoundly impact riparian areas by altering the fluvial processes that drive riparian vegetation communities. Dam removal may reverse these effects; however, very few studies have examined the response of riparian vegetation to large dam removal and associated disturbances, such as the release of sediment. Understanding how dam removal impacts downstream riparian vegetation is crucial as dam removal becomes more common. The Elwha River, Washington, is the location of the largest dam removals to date and provides an unprecedented opportunity to explore questions related to dam removal and riparian vegetation. The objectives of this …