Forest Biology Commons^™

Contribución A La Conservación De La Orquídea Rodriguezia Granadensis(Lindl.) Rchb.F. En La Hacienda Betania (Fusagasugá, Colombia), Arlette Ivonne Gil Clavijo, Jenny Paola Moreno López, Laguandio Del Cristo Banda Sánchez

Ciencias Agropecuarias

Esta cartilla presenta a la comunidad la información generada en el proyecto de investigación denominado “Aproximación a la ecología de orquídeas nativas en el ecosistema hacienda Betania con proyección a su conservación, manejo y producción”, el cual fue desarrollado por el Grupo de Investigación PROSAFIS de la Universidad de Cundinamarca. Este manuscrito es una contribución al manejo, tuvieron y valoración de las orquídeas nativas, destacando la orquídea Rodriguezia granadensis, presente en ciertos relictos agroecológicos en áreas de influencia de Fusagasugá. Los resultados obtenidos en la investigación mostraron la preferencia o alta adaptación de R. granadensis a los forofitos de cítricos ...

Responses Of Nutrient Resorption To Human Disturbances In Phoebe Bournei Forests, Dehuang Zhu, Suhong Peng, Jinyan Wang, Dafeng Hui

Biology Faculty Research

Nutrient resorption plays an important role in the nutrient conservation of plants and ecosystem nutrient cycling. Although community succession and nutrient addition could regulate plant nutrient resorption, how resorptions of foliar nutrients vary with human disturbances remains unclear. With the economic development, Phoebe bournei forests (PF) have suffered varying degrees of human disturbances in China. In this study, the leaf nutrient resorption efficiency (RE) of the PF under two disturbances (i.e., severe and mild disturbances) were investigated. Results showed that the phosphorus (P) contents of green leaf, senesced leaf, and soil were low under both disturbances, reflecting that the ...

Diversity-Productivity Relationships In Forests Of The Southeastern United States: Leveraging National Inventory Data And Tree Functional Traits, Elizabeth Baach

Theses and Dissertations

Numerous studies have evaluated the relationship between biodiversity and productivity, with general trends suggesting a positive relationship. While most studies only use species richness, this study also analyzed how productivity changes with functional diversity and Shannon’s diversity index. Functional diversity gives important context to the examination of biodiversity-productivity relationships due to the direct link between organisms’ functional traits and their role in a given ecosystem. This study used data from the USDA Forest Service Forest Inventory and Analysis (FIA) database collected in Alabama, Louisiana, and Mississippi to estimate plot-level productivity and diversity. Structural equation modeling was used to determine ...

Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi

Theses and Dissertations

Anticipated climate change and increasing wood demand require dependable diameter growth models for adaptive forest management. We used a mixed-effects modeling approach with Forest Inventory and Analysis (FIA) data to fit diameter growth models for loblolly pine, other softwood species (slash pine, shortleaf pine, and longleaf pine), sweetgum, and other hardwood (southern red oak, red maple, and water oak) species. Climatic variables coupled with individual tree attributes and competition factors improved climate insensitive models. Growth of loblolly pine and sweetgum was positively correlated with mean temperature of the coldest month. Mean temperature of the warmest month negatively influenced diameter growth ...

Climatic Influences On Summer Use Of Winter Precipitation By Trees, Gregory R. Goldsmith, Scott T. Allen, Sabine Braun, Rolf T. W. Siegwolf, James W. Kirchner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Trees in seasonal climates may use water originating from both winter and summer precipitation. However, the seasonal origins of water used by trees have not been systematically studied. We used stable isotopes of water to compare the seasonal origins of water found in three common tree species across 24 Swiss forest sites sampled in two different years. Water from winter precipitation was observed in trees at most sites, even at the peak of summer, although the relative representation of seasonal sources differed by species. However, the representation of winter precipitation in trees decreased with site mean annual precipitation in both ...

Species Diversity And Growth Rates Of Overstory Vegetation Over 25 Years In Response To Physical And Chemical Properties In Long-Term Monitoring Plots At The University Of Mississippi Field Station, Mitchell Tharp

Honors Theses

Overstory vegetation for twenty-two long-term monitoring plots (LTMPs) was sampled from 1996 to 2021 to study the changes in vegetation due to natural and human disturbance. From the fall of 2020 through the fall of 2021, the overstory of the 22 LTMPs was resampled and soil samples were collected from each plot. The circumference at breast height (CBH) and species diversity were recorded and compared to previous years’ data. The objectives of this study were to: (1) document changes in the overstory species of the LTMPs, (2) measure growth rates of surviving trees, (3) survey how elevation and slope impact ...

Assessing The Long-Term Effects Of Natural Disturbance-Based Silvicultural On The Avian Assemblage At The Acadian Forest Ecosystem Research Program, Carl Pohlman

Electronic Theses and Dissertations

Active forest management alters the resources available to forest-obligate species. Large-scale intensive management practices where timber production is the primary objective can lead to notable ecological changes in forest ecosystems. A key concept of ecological forestry is to design forest management activities to emulate natural disturbance regimes as a way to maintain the ecological integrity of forests. The Acadian Forest Ecosystem Research Program (AFERP) was undertaken as an experimental demonstration of management reflective of the region’s disturbance regime, which typically produces small canopy gaps. AFERP includes nine research areas assigned to three silvicultural treatments: unharvested control, small gap (expanding-group ...

Plant Community Responses To Interactive Anthropogenic Disturbances Along A Natural-Wildland-Urban Gradient And Undergraduate Students’ Attitudes Toward Disturbances, Mali M. Hubert

Doctoral Dissertations

Anthropogenic disturbances are defined as any change caused by human activity that alters biodiversity. Wildfire and urbanization disturbances are among the most influential on the landscape because of their individual and interactive properties. Areas deemed wildland-urban interfaces (WUI; area where environment intermingles with human-built structures) are increasing near protected lands because of human population growth and movement, which often facilitates fire ignitions by humans. Houses that are adjacent to or overlap with wildland vegetation can complicate protection of urban development and wildlands from fires. The expansion of the WUI due to population growth will exacerbate fire risk, which can ultimately ...

Chronic Wasting Disease In Deer And Elk Herds In Arkansas, Baker Kendrick

Scholars Day Conference

This presentation gives a broad introduction to Chronic Wasting Disease. It goes over what the disease is and its history, symptoms, how it works on a molecular level, effects on the hunting industry, host range, management and regulation, transmission, treatment, and research.

Landscapes Are Cornerstones Of Sustainability Programs, Don Spence

Sustainability Conference

Typical American landscapes are not sustainable in an economic or biological framework. The essence of the idea of sustainable growth and development are centered on the idea that those activities are not degrading natural resources or that they are outstrip budgets. A significant piece of any sustainable management plan is tied to how we manage our landscapes, how we use plants; specifically, how much grass there is, and how many native plants there are. Sustainable landscapes should require less chemical and financial inputs, which in the end, saves money and increases the biological value of the land and creates a ...

Leaf Phenology Of Callery Pear: Spring, Margaret A. Maloney, Abby Hay, Eric B. Borth, Ryan W. Mcewan

Five Rivers MetroParks Collaboration Data Archive

No abstract provided.

The Role Of Leaf Decomposition In Macroinvertebrate Colonization, Bethany Mabel Lian Schorr, Kevin Geedey

Independent Research Projects

Decomposition 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 ...

The Study Of Tree Biomass Calculation By Comparing Partial Harvest Method With The Allometric Equations Method, Kanlayarat Jantawong, Titinan Pothong

Journal of Bioresource Management

This study aimed to investigate the effective of partial harvest method used for tree biomass estimation. Such method was analyzed for the correlation in compare with invented allometric equations. The advantages and disadvantages of those methods were discussed. The significantly difference between estimation methods were analyzed. As a result, tree biomass calculated by the Brown’s allometric equation produced highest results, followed by the partial harvest method, Tsutsumi’s, Chave’s and Pothong’s equations respectively. The selected allometric equations showed the positive correlation with partial harvest method. The highest positive correlation was found between the partial harvest method and ...

A Comparison Of Wildfire Adaptive Traits In Juvenile Conifers Of The Northern Rockies, Andie Sonnen

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Wildfire is an importance disturbance that continues to shape the ecosystems of the northern Rockies through varying patterns of frequency and intensity. Due to historical fire suppression and the hotter and drier conditions brought upon by anthropogenic climate change, wildfire frequency and intensity is increasing. These increases will alter vegetation structure and composition, but the degree to which is unknown.

Individual plant traits can offer insight into how these vegetation communities will shift, especially the particular traits that reduce fire-related mortality. To survive wildfires, juvenile northern conifers employ two strategies: increasing their bark thickness and increasing their crown height. To ...

Poor Acclimation To Experimental Field Drought In Subalpine Forest Tree Seedlings, Alex Goke, Patrick H. Martin

Biological Sciences: Faculty Scholarship

The ability of tree species to acclimate and tolerate projected increases in drought frequency and intensity has fundamental implications for future forest dynamics with climate change. Inquiries to date on the drought tolerance capacities of tree species, however, have focused almost exclusively on mature trees with scant in situ work on seedlings, despite the central role that regeneration dynamics play in forest responses to changing conditions. We subjected naturally established seedlings of co-dominant subalpine conifer species (Abies lasiocarpa and Picea engelmannii) in the southern Rocky Mountains to 2 years of in situ summer precipitation exclusion, simulating summer drought conditions similar ...

Investigating Seed Maturation And Mortality: A Mechanism For Post-Fire Regeneration In Non-Serotinous Conifers, Madeleine A. Lopez

Cal Poly Humboldt theses and projects

Climate warming and associated dry conditions are contributing to increased fire frequency, severity, and size, for many regions in western North America. These changes in fire activity have prompted concern over the long-term persistence of some conifer species, specifically those not adapted to withstand high-severity fire. However, regeneration of non-serotinous conifer species is possible if the timing of fire occurs following seed maturation, and within a heat range that seeds can withstand, in a regenerative mechanism termed “facultative serotiny.” To address this mechanism, I determined the timing of conifer seed maturation using viability testing for four California conifer species: ponderosa ...

Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo

Cal Poly Humboldt theses and projects

The 2012-2016 California drought was the most severe in the state’s recorded history, contributing to the death of millions of trees. While the effects of this drought on forests are relatively well studied in the central and southern Sierra Nevada, less is known about its effects on the heavily timbered and diverse forests of northern California. Through sampling 54 0.25 ha plots in northern California, this study compared tree mortality and regeneration patterns before, during, and after California’s most recent record-setting drought. This study evaluated 1) the influence of habitat and competitive covariates on mortality and regeneration ...

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 = 0 ...

Coupled Structure-Function Responses To Disturbance: High Structural Complexity Resistance Supports Primary Production Resistance, Kerstin M. Niedermaier

Theses and Dissertations

The capacity of forests to resist structural change and retain material legacies–the biotic and abiotic resources that persist through disturbance–is crucial to sustaining ecosystem functioning after disturbance. However, the role of forest structure as both a material legacy and feature supporting carbon (C) cycling stability following disturbance has not been widely investigated. We used a large-scale disturbance manipulation to ask whether LiDAR-derived canopy structures as material legacies drive 3-year responses of NPP to a range of disturbance severity levels. As part of the Forest Resilience Threshold Experiment (FoRTE) in northern Michigan, USA we simulated phloem-disrupting disturbances at a ...

Advancing Forest Structure-Function Relationships: Linking Above- And Belowground Structure To Soil Respiration, Laura J. Hickey

Theses and Dissertations

Variation in the soil-to-atmosphere C flux, or soil respiration (Rs), is influenced by a suite of biotic and abiotic factors, including soil temperature, soil moisture, and root biomass. However, whether canopy structure is tied to soil respiration through its simultaneous influence over these drivers is not known. We assessed relationships between measures of above- and belowground vegetation density and complexity, and evaluated whether Rs is linked to remotely sensed canopy structure through pathways mediated by established biotic and abiotic mechanisms. Our results revealed that, at stand-scale, canopy rugosity–a measure of complexity–and vegetation area index were coupled to soil ...